Immunophenotypical and pathological changes in dogs experimentally infected with Ehrlichia canis / Alterações imunofenotípicas e patológicas em cães experimentalmente infectados por Ehrlichia canis

Canine monocytic ehrlichiosis (CME) is one of the most important tick-borne diseases worldwide, with multisystemic presentations. Immune dysregulation has been proposed as the primary mechanism involved in its pathogenesis and in tissue injury in dogs with CME. Experimental infection of German Shepherd dogs in the present study demonstrated that CME caused marked pathological changes in their lymph nodes and spleen, and also gave rise to mononuclear infiltration in organs and tissues. Immunophenotyping of cells in lymph nodes, spleen and injured tissues highlighted differences in lymphocyte subsets, local expression of immunoglobulin subclasses and MHCII molecules between infected and control dogs. These findings suggest that the immunophenotypic and immunopathological changes in dogs with acute experimental CME are related to Th1 bias and compartmentalized immune response.(AU)

A erliquiose monocítica canina (EMC) é uma das doenças veiculadas por carrapatos com apresentações multisistêmicas mais relevantes em todo o mundo. A desregulação do sistema imune vem sendo proposta como o principal mecanismo envolvido na patogênese e lesão de tecidos em cães com EMC. A infecção experimental de pastores alemães nesta pesquisa evidenciou marcadas alterações patológicas em linfonodos, baço e também infiltração mononuclear em órgãos e tecidos. A imunofenotipagem de células em linfonodos, baço e tecidos lesados destacou diferenças em subconjuntos de linfócitos, expressão local de subclasses de imunoglobulinas e de moléculas MHCII entre cães infectados e controle. Esses achados sugerem que um viés Th1 e uma resposta imune compartimentalizada estão relacionados às alterações imunofenotípicas e imunopatológicas em cães com EMC experimental aguda.(AU)

Linfoma extranodal de células B em vesícula urinária de um cão / Extranodal B-cell lymphoma in the urinary bladder in a dog

O linfoma é uma neoplasia de alta recorrência na rotina oncológica de medicina veterinária. Pode ser classificado em linfoma Hodgking-liked, com raros casos descritos somente em felinos,e não Hodgking, sendo este segundo o mais comum, subdividido em linfomas B ou T. O objetivo deste trabalho foi relatar a conduta clínica, diagnóstica e terapêutica do caso de uma cadela, de 12 anos, sem raça definida, que manifestava disúria, prostração, dor abdominal e ao exame físico a presença de uma massa na região hipogástrica. Esta foi diagnosticada com linfoma de grandes células por meio de exames de citologia e biópsia, com solicitação do exame de imunoistoquímica que confirmou linfoma difuso de grandes células de imunofenótipo B. Sem o envolvimento de nenhum outro sistema, classificou-se como linfoma primário de bexiga extranodal. O animal passou pelo tratamento quimioterápico realizando nove sessões de quimioterapia pelo protocolo de CHOP, contudo devido ao agravamento do caso a paciente veio a óbito cerca de sete meses após o diagnóstico da doença. O caso estudado foi de extrema importância para a compreensão de linfomas primários de bexiga em razão da escassez de informações relacionadas na literatura. Ainda, o cão é um excelente modelo experimental de linfomas não Hodgking em humanos, consequentemente compreender essa doença em cães promove a evolução conjunta da medicina humana.

Lymphoma is a highly recurrent rate neoplasm in the oncology routine of veterinary medicine. It can be classified into Hodgking-like, rarely described just in felines, and non-Hodgking lymphoma, the latter being the most commun, subdivided into B-cell lymphoma and T-cell lymphoma. The objective of this study was to report the clinical and therapeutic conduct within the diagnosis procedures of a 12-years-old female dog, mixed breed, who manifested dysuria, prostation, abdominal pain and on the physical examination a mass in the hypogastric region was noticed. This was diagnosed as a large cell lymphoma by means cytology and biopsy, also immunohistochemistry was required which confirmed the diffuse large cell lymphoma of immunophenotyping B. Without any other sistem envolved, the neoplasm was classified as primary urinary bladder lymphoma extranodal. The animal underwent chemotherapy, performing nine sessions according to the Madison protocol, however, due to the worsening of the case, the patient died about seven months after the diagnosis of the disease. This case was extremely importante for the understanding of primary urinary bladder lymphomas due to the scarcity of informations in the literature. Also, dog is an excellent experi,emtal model of non Hodgking lymphomas in humans, thus understandig this disease in dogs promotes the joint evolution of human medicine.

Linfoma de células T na cavidade nasal de caprino / T-cell lymphoma in the nasal cavity in goat

Background: Lymphomas are considered uncommon in goats, being the multicentric form with the highest number of cases for the species. Primary intranasal lymphomas are often diagnosed in dogs, cats, and humans. In the literature, there is only a description of a multicentric case involving the frontal sinuses and mucosa of the nasal cavity in a goat; therefore, it is important to describe unusual cases of this disease for the inclusion of new clinical and pathological characteristics in the ruminant clinic medicine. The objective of this work is to describe a case of T-cell lymphoma in the nasal cavity of a young goat. Case: The animal had dyspnea and respiratory noise for 15 days. Clinical examination showed nodulation in the right nasal cavity associated with serosanguinous secretion. Tracheostomy was performed; however, after 30 days the animal was euthanized. A sagittal plane of the head showed a pinkish-gray mass in the right and left nasal cavity, with a smooth, multilobulated surface, smooth adhering to the rostral portion of the dorsal concha and occluding the dorsal nasal meatus. Submandibular lymph nodes were slightly enlarged. Histopathological examination of the nasal cavity revealed a non-encapsulated, poorly delimited and ulcerated tumor composed of round cells arranged in a mantle supported by a discrete fibrovascular stroma extending the mucosa and lamina propria. Cells were round with sparse, eosinophilic and poorly delimited cytoplasm. Nuclei varied from round to elongated with condensed chromatin and evident nucleoli. Occasionally, aberrant nuclei, reniform shape and multinucleated cells were seen. Pleomorphism was moderate characterized by anisocytosis and anisocariosis. Typical and atypical mitosis were frequent (0-4 per field of highest magnification [400x]). Amidst the neoplasm, there were multifocal areas of necrosis and hemorrhage associated with a mild lymphocytic inflammatory infiltrate. Immunohistochemistry showed positive immunostaining for Vimentin antibodies and CD3, and negative for pan CK and CD20. Discussion: The lymphomas immunophenotyping is little used when it comes to farm animals, and there are few studies that use this technique for the definitive diagnosis of these neoplasms for small ruminants. The use of this technique must be considered in each case, in order to determine the pathogenesis, the accurate diagnosis and the origin of the neoplastic lymphocytes. In goats, T-cell lymphomas are the most diagnosed, although cases of multicentric B-cell lymphomas with ocular involvement have been diagnosed. In view of the clinical picture of the case described, infectious rhinitis already described in goats, such as aspergillosis and protothecosis, should be included as differential diagnoses. However, the anatomopathological findings facilitate the direction of the diagnosis, since infectious rhinitis presents as nodules / ulcerated masses or focal areas of necrosis associated with purulent secretion and in the histopathological examination it is possible to observe the intralesional etiological agents. In addition, the enzootic ethmoidal tumor must be included, as it has similar clinical signs and affects young animals, but they are adenomas/adenocarcinomas that affect the ethmoidal nasal shells induced by a retrovirus. Lymphomas in the caprine species are rare in the Northeastern semi-arid, but that in the present diagnostic routine occasionally occurs, being important the first description of its nasal shape for its inclusion in the differential diagnoses of diseases that present with clinical obstruction and dyspnea for the species.

Clonality test by PCR - PARR in real time of canine lymphomas

Lymphoma is a neoplasm of hematopoietic origin that affects canines. The proper establishment of prognosis and rapid institution of treatment are essential for a better quality of life, and immunophenotyping is one of the tools used for this purpose. The objective of this study was to perform a clonality test for immunophenotypic characterization of canine lymphomas using the polymerase chain reaction (PCR) for antigen receptor rearrangements (PARR) technique in real-time from samples fixed in formalin and embedded in paraffin. The 23 analyzed samples were fixed in formalin and embedded in paraffin canine lymphoma from the collection Laboratory of Histopathology of the Animal Pathology Area of the Departament of Veterinary Medicine - Federal Rural University of Pernambuco (UFRPE). Samples were processed, their DNA was extracted, quantified, diluted, and standardized at a concentration of 50 ng/µL. After extraction, all samples were subjected to conventional PCR for endogenous control (detection of the IgM target region), in which the extracted DNA was amplified in a final volume of 25 µL. The 128 bp amplified product was detected by 1.5% agarose gel electrophoresis. Of the 23 samples analyzed for the detection of the conserved region referring to the endogenous gene, 91.30% (21/23) amplified the conserved region Cµ by conventional PCR, and two samples 8.70% (2/23) were negative. Endogenous control positive samples were subjected to real-time PCR-PARR for detection of IgH Major and IgH Minor for B lymphocytes (LB), and TCRy for lymphocytes T (LT) target regions. All reactions were performed in duplicate to reduce the risk of false-positive or false-negative results due to technical errors. Samples previously confirmed by immunohistochemistry were used as positive controls for T cell and B cell lymphoma, and MilliQ water was used as a negative reaction control. After amplification, the melting curve gradually increased the temperature by 1o C/5 s to 95o C during continuous fluorescence monitoring. Of the 21 samples analyzed, 100.00% (21/21) demonstrated clonal amplification. Of these, 57.15% (12/21) were positive for phenotype B, and 42.85% (9/21) were positive for phenotype T. Due to the importance of researching and confirming samples from files fixed and embedded in paraffin samples in laboratories, PCR-PARR is a good tool for this purpose. In the present study, real-time PCR analysis demonstrated greater sensitivity in the characterization of the immunophenotype of lymphomas from old samples fixed in formalin and embedded in paraffin. The temperature of melting curve analysis may vary depending on the amount of DNA and its quality. In the present study, it was found that the average melting temperature in the samples varied between ± 3o C when compared to that in the control sample for LB and LT, 83.5o C and 80o C, respectively: in the literature, there is a relative difference in this temperature, which may vary up to 4o C. Real-time PCR-PARR was satisfactory in the characterization of the immunophenotype of canine lymphomas from formalin-fixed and paraffin-embedded samples; therefore, its use is recommended for both retrospective studies. The use of PCR-PARR associated with histopathological and/or cytopathological examination in cases of canine lymphomas strongly helps pathologists, provide a safe establishment of the immunophenotype, minimize errors, and optimize the diagnosis, thus directly contributing to the establishment of the prognosis.(AU)

Linfoma difuso de grandes células em um buldogue inglês de dois anos: relato de caso / Diffuse large-cell lymphoma in a two-year-old english bulldog: case report

O linfoma é a neoplasia hematopoiética mais frequentemente diagnosticada na clínica de pequenos animais, sendo caracterizado por uma proliferação descontrolada de linfócitos, acometendo principalmente animais idosos. Dentre os achados clínicos mais comuns da doença, a linfadenopatia periférica recebe destaque. Manifestações clínicas como perda de peso, anorexia, edema subcutâneo, êmese, massas cutâneas, disfagia, ascite e dispnéia são também frequentemente encontradas. O diagnóstico dos linfomas é de extrema importância, sendo primordial para estabelecimento do prognóstico do animal, podendo ser feito através da análise citomorfológica de amostras obtidas por punção aspirativa e avaliação histopatológica. A poliquimioterapia é realizada como protocolo terapêutico de eleição para animais com linfoma. Foi atendido no Serviço de Clínica e Cirurgia Oncológica do Hospital Veterinário da Universidade Federal de Uberlândia (HV-UFU), um Buldogue Inglês, de dois anos de idade, apresentando linfonodonomegalia generalizada e diagnosticado com linfoma difuso de grandes células. O diagnóstico foi obtido por exame histopatológico e o imunohistoquímico revelou imunofenotipagem B. O paciente foi submetido a quimioterapia, sendo escolhido o protocolo Winscosin (CHOP) de 19 semanas com remissão completa ao término do protocolo. O objetivo deste trabalho é relatar um caso de linfoma difuso de grandes células em um Buldogue Inglês de dois anos de idade com remissão completa após a realização de quimioterapia.

Lymphoma is the hematopoietic neoplasm most frequently diagnosed in the clinic of small animals, being characterized by an uncontrolled proliferation of lymphocytes, affecting mainly elderly animals. Among the most common clinical findings of the disease, peripheral lymphadenopathy is highlighted. Clinical manifestations such as weight loss, anorexia, subcutaneous edema, emesis, skin masses, dysphagia, ascites and dyspnea are also frequently encountered. The diagnosis of lymphomas is extremely important, being essential for establishing the animal's prognosis and can be done through cytomorphological analysis of samples obtained by aspiration puncture and histopathological evaluation. Polychemotherapy is performed as the therapeutic protocol of choice for animals with lymphoma. It was treated at Serviço de Clínica e Cirurgia Oncológica do Hospital Veterinário da Universidade Federal de Uberlândia (HV-UFU), a two-year-old English Bulldog, with generalized lymph node enlargement and diagnosed with diffuse large cell lymphoma. The diagnosis was obtained by histopathological and immunohistochemical examination and revealed immunophenotyping B. The patient underwent chemotherapy, and the 19- week Winscosin (CHOP) protocol was chosen with complete remission at the end of the protocol. The aim of this work is to report a case of diffuse large cell lymphoma in a two-year-old English Bulldog with complete remission after chemotherapy.

A comparative evaluation of methods for estimating the colostrum quality in sows / Avaliação comparativa de métodos para estimar a qualidade do colostro em porcas

Colostrum is the main source of immunoglobulins (Ig) for neonate piglets and plays a crucial role within the health and growth of the piglet. Currently in pig farming, there are still no widespread practical methods for measuring the Ig concentration in colostrum at herd level. We evaluated sows' colostrum IgG concentration using an optical and a digital Brix refractometer and their performance was correlated to an IgG ELISA test, and flow cytometry. Colostrum concentrations of IgG and IgA averaged 74.05 ± 21.37mg/mL and 20.2 ± 5.32mg/mL respectively. The mean value of the Brix percentages for optical refractometer was 26.32%, and for digital was 28.32%. The Brix refractometer measurements of colostrum samples presented high correlation for IgG content analyzed by ELISA (Optical = 0.74, Digital = 0.87; P <0.001). Considering the immunophenotyping, the values for IgG and IgA lymphoblasts indicated a highly significant relationship to ELISA (IgG=0.77, IgA=0.84; P<0.001). The Brix refractometer can be considered a useful tool to be included in a colostrum monitoring program to improve potentially neonatal health. In addition, we demonstrated that flow cytometry can be an important tool to analyze and characterize the immunological potential of sow colostrum.(AU)

O colostro é a principal fonte de imunoglobulinas (Ig) para leitões recém-nascidos e desempenha um papel crucial na saúde e no crescimento dos leitões. Atualmente, na suinocultura, ainda não existem métodos amplamente utilizados na prática de produção para medir a concentração de imunoglobulinas no colostro suíno. Avaliou-se a concentração de IgG no colostro de porcas usando refratômetros Brix óptico e digital, e o desempenho foi comparado com ELISA e citometria de fluxo. As concentrações de IgG e IgA no colostro foram 74,05 ± 21,37mg/mL e 20,2 ± 5,32mg/mL, respectivamente. A percentagem de Brix média das amostras de colostro para o refratômetro óptico foi 26,32%, e para o digital foi 28,32%. As medições dos refratômetros de Brix apresentaram elevada correlação com a concentrações de IgG medidas por ELISA (óptico=0,74, digital=0,87; P<0,001). Considerando a imunofenotipagem, os valores dos linfoblastos IgG e IgA apresentaram alta correlação com o ELISA (IgG=0,77, IgA=0,84; P<0,001). O refratômetro Brix pode ser considerado uma ferramenta útil para ser incluída em um programa de monitoramento de colostro para melhorar a saúde neonatal. Além disso, foi demonstrado que a citometria de fluxo pode ser uma ferramenta importante para analisar e caracterizar o potencial imunológico do colostro de porcas.(AU)

Linfoma difuso de grandes células em um buldogue inglês de dois anos: relato de caso / Diffuse large-cell lymphoma in a two-year-old english bulldog: case report

O linfoma é a neoplasia hematopoiética mais frequentemente diagnosticada na clínica de pequenos animais, sendo caracterizado por uma proliferação descontrolada de linfócitos, acometendo principalmente animais idosos. Dentre os achados clínicos mais comuns da doença, a linfadenopatia periférica recebe destaque. Manifestações clínicas como perda de peso, anorexia, edema subcutâneo, êmese, massas cutâneas, disfagia, ascite e dispnéia são também frequentemente encontradas. O diagnóstico dos linfomas é de extrema importância, sendo primordial para estabelecimento do prognóstico do animal, podendo ser feito através da análise citomorfológica de amostras obtidas por punção aspirativa e avaliação histopatológica. A poliquimioterapia é realizada como protocolo terapêutico de eleição para animais com linfoma. Foi atendido no Serviço de Clínica e Cirurgia Oncológica do Hospital Veterinário da Universidade Federal de Uberlândia (HV-UFU), um Buldogue Inglês, de dois anos de idade, apresentando linfonodonomegalia generalizada e diagnosticado com linfoma difuso de grandes células. O diagnóstico foi obtido por exame histopatológico e o imunohistoquímico revelou imunofenotipagem B. O paciente foi submetido a quimioterapia, sendo escolhido o protocolo Winscosin (CHOP) de 19 semanas com remissão completa ao término do protocolo. O objetivo deste trabalho é relatar um caso de linfoma difuso de grandes células em um Buldogue Inglês de dois anos de idade com remissão completa após a realização de quimioterapia.(AU)

Lymphoma is the hematopoietic neoplasm most frequently diagnosed in the clinic of small animals, being characterized by an uncontrolled proliferation of lymphocytes, affecting mainly elderly animals. Among the most common clinical findings of the disease, peripheral lymphadenopathy is highlighted. Clinical manifestations such as weight loss, anorexia, subcutaneous edema, emesis, skin masses, dysphagia, ascites and dyspnea are also frequently encountered. The diagnosis of lymphomas is extremely important, being essential for establishing the animal's prognosis and can be done through cytomorphological analysis of samples obtained by aspiration puncture and histopathological evaluation. Polychemotherapy is performed as the therapeutic protocol of choice for animals with lymphoma. It was treated at Serviço de Clínica e Cirurgia Oncológica do Hospital Veterinário da Universidade Federal de Uberlândia (HV-UFU), a two-year-old English Bulldog, with generalized lymph node enlargement and diagnosed with diffuse large cell lymphoma. The diagnosis was obtained by histopathological and immunohistochemical examination and revealed immunophenotyping B. The patient underwent chemotherapy, and the 19- week Winscosin (CHOP) protocol was chosen with complete remission at the end of the protocol. The aim of this work is to report a case of diffuse large cell lymphoma in a two-year-old English Bulldog with complete remission after chemotherapy.(AU)

Histopathological and immunophenotypical characterization of canine multicentric lymphoma in Brazil: a study of 203 cases / Caracterização histopatológica e imunofenotípica do linfoma multicêntrico canino no Brasil: um estudo de 203 casos

The immunophenotype is regarded as an independent prognostic factor in high-grade lymphomas, seeing that lymphomas of T-cell origin are associated with shorter survival time. Although a number of studies have evaluated the immunophenotypical profile of lymphoma in the USA and Europe, Brazilian research on the matter remains scarce. Exact characterization of the histopathological type is crucial to establish proper treatment and prognosis. This study evaluated the database of immunohistochemistry laboratories that perform immunophenotyping of canine lymphoma in Brazil. A total of 203 cases of multicentric lymphoma were classified according to the WHO classification. Immunophenotyping was able to identify 71.4% lymphomas of B-cell line, 27.1% of T-cell line and 1.5% of non-B cells and non-T cell lines. Diffuse large B-cell lymphoma was the most common with 59.1% of the cases. Among T-cell lymphomas, lymphoblastic was the most common (11.33% of the cases). Even though canine lymphomas tend to be high-grade, indolent lymphomas comprised 11.82% of the cases and T-zone lymphoma was the most prevalent (8.86%). The immunophenotype of multicentric lymphoma in Brazil is similar to those in other parts of the world, which suggests similar etiologic factors to the development of this disease.(AU)

O imunofenótipo é considerado um fator prognóstico independente em linfomas de alto grau, visto que os linfomas de origem de células T estão associados a menor tempo de sobrevida. Apesar de vários estudos terem avaliado o perfil imunofenotípico do linfoma nos EUA e na Europa, a pesquisa brasileira sobre o assunto ainda é escassa. A caracterização exata do tipo histopatológico é crucial para estabelecer o tratamento e o prognóstico adequados. Este estudo avaliou a base de dados de laboratórios de imuno-histoquímica que realizam imunofenotipagem do linfoma canino no Brasil. Um total de 203 casos de linfoma multicêntrico foi classificado de acordo com a classificação da OMS. A imunofenotipagem foi capaz de identificar 71,4% dos linfomas da linhagem de células B, 27,1% da linhagem de células T e 1,5% das linhagens de células não B e não T. O linfoma difuso de grandes células B foi o mais comum em 59,1% dos casos. Entre os linfomas de células T, o linfoblástico foi o mais comum (11, 33% dos casos). Embora os linfomas caninos tendam a ser de alto grau, os linfomas indolentes representaram 11,82% dos casos e o linfoma da zona T foi o mais prevalente (8,86%). O imunofenótipo do linfoma multicêntrico no Brasil é semelhante ao de outras partes do mundo, o que sugere fatores etiológicos semelhantes ao desenvolvimento dessa doença.(AU)

Histopathological and immunophenotypical characterization of canine multicentric lymphoma in Brazil: a study of 203 cases / Caracterização histopatológica e imunofenotípica do linfoma multicêntrico canino no Brasil: um estudo de 203 casos

The immunophenotype is regarded as an independent prognostic factor in high-grade lymphomas, seeing that lymphomas of T-cell origin are associated with shorter survival time. Although a number of studies have evaluated the immunophenotypical profile of lymphoma in the USA and Europe, Brazilian research on the matter remains scarce. Exact characterization of the histopathological type is crucial to establish proper treatment and prognosis. This study evaluated the database of immunohistochemistry laboratories that perform immunophenotyping of canine lymphoma in Brazil. A total of 203 cases of multicentric lymphoma were classified according to the WHO classification. Immunophenotyping was able to identify 71.4% lymphomas of B-cell line, 27.1% of T-cell line and 1.5% of non-B cells and non-T cell lines. Diffuse large B-cell lymphoma was the most common with 59.1% of the cases. Among T-cell lymphomas, lymphoblastic was the most common (11.33% of the cases). Even though canine lymphomas tend to be high-grade, indolent lymphomas comprised 11.82% of the cases and T-zone lymphoma was the most prevalent (8.86%). The immunophenotype of multicentric lymphoma in Brazil is similar to those in other parts of the world, which suggests similar etiologic factors to the development of this disease.(AU)

O imunofenótipo é considerado um fator prognóstico independente em linfomas de alto grau, visto que os linfomas de origem de células T estão associados a menor tempo de sobrevida. Apesar de vários estudos terem avaliado o perfil imunofenotípico do linfoma nos EUA e na Europa, a pesquisa brasileira sobre o assunto ainda é escassa. A caracterização exata do tipo histopatológico é crucial para estabelecer o tratamento e o prognóstico adequados. Este estudo avaliou a base de dados de laboratórios de imuno-histoquímica que realizam imunofenotipagem do linfoma canino no Brasil. Um total de 203 casos de linfoma multicêntrico foi classificado de acordo com a classificação da OMS. A imunofenotipagem foi capaz de identificar 71,4% dos linfomas da linhagem de células B, 27,1% da linhagem de células T e 1,5% das linhagens de células não B e não T. O linfoma difuso de grandes células B foi o mais comum em 59,1% dos casos. Entre os linfomas de células T, o linfoblástico foi o mais comum (11, 33% dos casos). Embora os linfomas caninos tendam a ser de alto grau, os linfomas indolentes representaram 11,82% dos casos e o linfoma da zona T foi o mais prevalente (8,86%). O imunofenótipo do linfoma multicêntrico no Brasil é semelhante ao de outras partes do mundo, o que sugere fatores etiológicos semelhantes ao desenvolvimento dessa doença.(AU)

The influence of splenic tissue on the survival and TCD4 and TCD8 lymphocyte rates in rats subjected to fecal peritonitis induction

Purpose: Comparing survival rates of rats subjected to spleen procedures after fecal peritonitis induction. Assessing changes in TCD4 and CD8 lymphocyte rates before and after the procedures. Correlating animal survival with CD4 and CD8 lymphocytes. Methods: Thirty male Wistar rats were distributed into 3 groups of ten: spleen manipulation (SM); total splenectomy (TS); subtotal splenectomy with preservation of the inferior pole (IP). Rats were subjected to surgical procedure depending on the group. Seven days after surgery they underwent induction of peritonitis and survival time was recorded. All animals were subjected to two blood collections: before surgery and 70 days after it for TCD4/TCD8 lymphocyte counting. Results: Mean survival time was longer in the IP and SM groups and shorter in the TS group; there was significant difference between them. The comparison of the median number of CD4 did not present changes, whereas the comparison of the median number of CD8 decreased in the SM and IP groups. The correlation between the median number of TCD4 and TCD8 lymphocytes and the animals survival was not significant. Conclusion: The maintenance of splenic tissue contributed to increase the survival of rats and there was a change in the number of TCD8 lymphocytes.(AU)

Extranodal B cell lymphoma in the trachea of a domestic cat

Background: Primary tracheal tumors are considered uncommon in veterinary medicine and among them extranodal tracheal lymphoma, which is a neoplastic type, has rarely been described, especially with the use of immunophenotyping. Consequently, there is a lack of knowledge inherent to the characteristics of this tumor type in felines and as a result little information on how to deal with animals affected by this disease. Therefore, there is a need for more studies focusing on this matter. The objective of this work is to report a case of extranodal B cell lymphoma in the trachea of a domestic cat and point out the clinical and pathological characteristics of this neoplastic type. Case: A 5-year-old domestic cat, of an oriental breed, was taken to a veterinary clinic exclusively for cats in Rio de Janeiro, Brazil. The main complaint was difficulty in breathing and loss of appetite and historical data included intolerance to exercise. A clinical examination confirmed inspiratory dyspnea and upper respiratory sounds. Hematological and serum biochemical exams did not evidence any noteworthy changes and the cat was considered negative for feline viral leukemia and feline immunodeficiency viruses through serological and molecular testing. However, in the radiographic examination of the thoracic cervical region, an opacity was observed that occluded part of the tracheal lumen and this was suggestive of a mass in the initial third of the trachea, measuring 0.5 cm in diameter. The animal was stabilized and then 24 h after admission underwent inspection of the oral cavity and a biopsy of the tracheal mass was performed. Cytology of the specimen was suggestive of lymphoma. The treatment of choice was: lomustine with a single, oral dose of 10 mg; vincristine sulfate with a single intravenous dose of 0.75 mg/m²; and methylprednisolone acetate with a single...(AU)

Extranodal B cell lymphoma in the trachea of a domestic cat

Background: Primary tracheal tumors are considered uncommon in veterinary medicine and among them extranodal tracheal lymphoma, which is a neoplastic type, has rarely been described, especially with the use of immunophenotyping. Consequently, there is a lack of knowledge inherent to the characteristics of this tumor type in felines and as a result little information on how to deal with animals affected by this disease. Therefore, there is a need for more studies focusing on this matter. The objective of this work is to report a case of extranodal B cell lymphoma in the trachea of a domestic cat and point out the clinical and pathological characteristics of this neoplastic type. Case: A 5-year-old domestic cat, of an oriental breed, was taken to a veterinary clinic exclusively for cats in Rio de Janeiro, Brazil. The main complaint was difficulty in breathing and loss of appetite and historical data included intolerance to exercise. A clinical examination confirmed inspiratory dyspnea and upper respiratory sounds. Hematological and serum biochemical exams did not evidence any noteworthy changes and the cat was considered negative for feline viral leukemia and feline immunodeficiency viruses through serological and molecular testing. However, in the radiographic examination of the thoracic cervical region, an opacity was observed that occluded part of the tracheal lumen and this was suggestive of a mass in the initial third of the trachea, measuring 0.5 cm in diameter. The animal was stabilized and then 24 h after admission underwent inspection of the oral cavity and a biopsy of the tracheal mass was performed. Cytology of the specimen was suggestive of lymphoma. The treatment of choice was: lomustine with a single, oral dose of 10 mg; vincristine sulfate with a single intravenous dose of 0.75 mg/m²; and methylprednisolone acetate with a single...

Canine lymphomas diagnosed in southern Brazil from 2000 to 2017: epidemiology and immunophenotype / Linfomas caninos diagnosticados na região Sul do Rio Grande do Sul de 2000 a 2017: epidemiologia e imunofenótipo

Lymphoma is a neoplasm that originates from solid hematopoietic tissues and is one of the most common tumors in dogs. The goal of the present study was to perform a retrospective study of canine lymphomas diagnosed at the "Laboratório Regional de Diagnóstico", at the "Faculdade de Veterinária" of the "Universidade Federal de Pelotas" (LRD-UFPel) from 2000 to 2017, to determine the epidemiology and anatomical distribution, and to evaluate the histopathological and immunohistochemical aspects of each case according to the adapted Kiel classification. The protocols for necropsies and biopsies in the laboratory were reviewed. Lymphoma was diagnosed in 77 dogs. Approximately 37.7% (29/77) of affected dogs had no defined breed, while dogs with defined breeds accounted for 58.4% (45/77) of the diagnoses. The occurrence in males (40/77) was slightly higher than that in females (36/77), and the mean age was 8.1 years (1.4-17 years). The most affected age group was between six and 10 years of age with 31 cases (40.2%). Regarding the anatomical classification, the multicentric form was the most prevalent, accounting for 71.4% (55/77) of the diagnoses. In 40 cases that immunophenotyping was performed, B-cell lymphomas represented 62.5% of the diagnoses (25/40), while T-cell lymphomas corresponded to 37.5% of the diagnoses (15/40). The degree of malignancy according to the modified Kiel classification was low in 35% of lymphomas (14/40) and high in 65% of cases (26/40). The multicentric form was more frequent in the region of influence of the LRD-UFPel. Identification of the immunophenotype can improve the quality of life and survival in affected dogs since it allows the most appropriate treatment for each patient.(AU)

O linfoma é uma neoplasia com origem nos tecidos hematopoiéticos sólidos e é um dos tumores mais frequentes em cães. O objetivo do presente trabalho foi efetuar um estudo retrospectivo dos linfomas caninos recebidos no Laboratório Regional de Diagnóstico, da Faculdade de Veterinária da Universidade Federal de Pelotas (LRD-UFPel) de 2000 a 2017, determinando a epidemiologia e a distribuição anatômica, bem como os aspectos histopatológicos e imuno-histoquímicos de cada caso de acordo com a classificação de Kiel adaptada. Foram revisados os protocolos de necropsias e biópsias recebidos no laboratório identificando-se 77 casos de cães com diagnóstico de linfoma. A doença afetou cães sem raça definida em 37,7% (29/77) dos casos, enquanto os cães com raças definidas tiveram 58,4% (45/77) dos diagnósticos. A ocorrência em machos (40/77) foi discretamente maior do que em fêmeas (36/77) e a idade média foi de 8,1 anos (1,4-17 anos). A faixa etária mais acometida foi entre seis e 10 anos de idade com 31 casos (40,2%). Quanto à classificação anatômica a forma multicêntrica foi a mais prevalente atingindo 71,4% (55/77) dos diagnósticos. Em 40 casos em que a imunofenotipagem foi realizada, os linfomas de células B representaram 62,5% dos casos (25/40), enquanto os linfomas de células T equivaleram a 37,5% dos diagnósticos (15/40). O grau de malignidade de acordo com a classificação de Kiel modificada foi baixo em 35% dos linfomas (14/40) e alto em 65% dos casos (26/40). Conclui-se que a forma multicêntrica é mais frequente na região de influência do LRD-UFPel e que a identificação do imunofenótipo pode melhorar a qualidade de vida e dar maior sobrevida aos cães afetados uma vez que permite o tratamento mais adequado para cada caso.(AU)

Canine lymphomas diagnosed in southern Brazil from 2000 to 2017: epidemiology and immunophenotype / Linfomas caninos diagnosticados na região Sul do Rio Grande do Sul de 2000 a 2017: epidemiologia e imunofenótipo

Lymphoma is a neoplasm that originates from solid hematopoietic tissues and is one of the most common tumors in dogs. The goal of the present study was to perform a retrospective study of canine lymphomas diagnosed at the "Laboratório Regional de Diagnóstico", at the "Faculdade de Veterinária" of the "Universidade Federal de Pelotas" (LRD-UFPel) from 2000 to 2017, to determine the epidemiology and anatomical distribution, and to evaluate the histopathological and immunohistochemical aspects of each case according to the adapted Kiel classification. The protocols for necropsies and biopsies in the laboratory were reviewed. Lymphoma was diagnosed in 77 dogs. Approximately 37.7% (29/77) of affected dogs had no defined breed, while dogs with defined breeds accounted for 58.4% (45/77) of the diagnoses. The occurrence in males (40/77) was slightly higher than that in females (36/77), and the mean age was 8.1 years (1.4-17 years). The most affected age group was between six and 10 years of age with 31 cases (40.2%). Regarding the anatomical classification, the multicentric form was the most prevalent, accounting for 71.4% (55/77) of the diagnoses. In 40 cases that immunophenotyping was performed, B-cell lymphomas represented 62.5% of the diagnoses (25/40), while T-cell lymphomas corresponded to 37.5% of the diagnoses (15/40). The degree of malignancy according to the modified Kiel classification was low in 35% of lymphomas (14/40) and high in 65% of cases (26/40). The multicentric form was more frequent in the region of influence of the LRD-UFPel. Identification of the immunophenotype can improve the quality of life and survival in affected dogs since it allows the most appropriate treatment for each patient.(AU)

O linfoma é uma neoplasia com origem nos tecidos hematopoiéticos sólidos e é um dos tumores mais frequentes em cães. O objetivo do presente trabalho foi efetuar um estudo retrospectivo dos linfomas caninos recebidos no Laboratório Regional de Diagnóstico, da Faculdade de Veterinária da Universidade Federal de Pelotas (LRD-UFPel) de 2000 a 2017, determinando a epidemiologia e a distribuição anatômica, bem como os aspectos histopatológicos e imuno-histoquímicos de cada caso de acordo com a classificação de Kiel adaptada. Foram revisados os protocolos de necropsias e biópsias recebidos no laboratório identificando-se 77 casos de cães com diagnóstico de linfoma. A doença afetou cães sem raça definida em 37,7% (29/77) dos casos, enquanto os cães com raças definidas tiveram 58,4% (45/77) dos diagnósticos. A ocorrência em machos (40/77) foi discretamente maior do que em fêmeas (36/77) e a idade média foi de 8,1 anos (1,4-17 anos). A faixa etária mais acometida foi entre seis e 10 anos de idade com 31 casos (40,2%). Quanto à classificação anatômica a forma multicêntrica foi a mais prevalente atingindo 71,4% (55/77) dos diagnósticos. Em 40 casos em que a imunofenotipagem foi realizada, os linfomas de células B representaram 62,5% dos casos (25/40), enquanto os linfomas de células T equivaleram a 37,5% dos diagnósticos (15/40). O grau de malignidade de acordo com a classificação de Kiel modificada foi baixo em 35% dos linfomas (14/40) e alto em 65% dos casos (26/40). Conclui-se que a forma multicêntrica é mais frequente na região de influência do LRD-UFPel e que a identificação do imunofenótipo pode melhorar a qualidade de vida e dar maior sobrevida aos cães afetados uma vez que permite o tratamento mais adequado para cada caso.(AU)

Immunophenotyping, plasticity tests and nanotagging of stem cells derived from adipose tissue of wild rodent agouti (Dasyprocta prymnolopha) / Imunofenotipagem, testes de plasticidade e marcação com nanocristais de céluas-tronco derivadas de tecido adiposo em cutias

There is a growing interest in the study of unspecialized mesenchymal stem cells, for there are still some discussions about their in vitro behavior. Regenerative medicine is a science undergoing improvement which develops treatments as cell therapy using somatic stem cells. In several studies, adipose tissue is presented as a source of multipotent adult cells that has several advantages over other tissue sources. This study aimed to characterize and evaluate the tagging of mesenchymal stem cells from the agoutis adipose tissue (Dasyprocta prymonolopha), with fluorescent intracytoplasmic nanocrystals. Fibroblast cells were observed, plastic adherent, with extended self-renewal, ability to form colonies, multipotency by differentiation into three lineages, population CD90 + and CD45 - expression, which issued high red fluorescence after the tagging with fluorescent nanocrystals by different paths and cryopreserved for future use. It is possible to conclude that mesenchymal stem cells from agouti adipose tissue have biological characteristics and in vitro behavior that demonstrate its potential for use in clinical tests.(AU)

Há um interesse crescente no estudo das células estaminais mesenquimais, não especializadas, pois ainda existem algumas discussões sobre seu comportamento in vitro. A medicina regenerativa é uma ciência em fase de crescimento que desenvolve tratamentos como terapia celular utilizando células estaminais somáticas. Em vários estudos, o tecido adiposo é apresentado como uma fonte de células adultas multipotentes que tem várias vantagens em relação a outras fontes de tecido. Este estudo teve como objetivo caracterizar e avaliar a marcação de células estaminais mesenquimais do tecido adiposo de cutias (Dasyprocta prymnolopha) com nanocristais intracitoplasmáticos fluorescentes. Observaram-se células fibroblásticas, aderentes ao plástico, com autorrenovação prolongada, capacidade de formar colônias, diferenciação em três linhagens, população CD90 + e expressão CD45, que emitiram alta fluorescência vermelha após a marcação com nanocristais fluorescentes por diferentes vias, e criopreservadas para uso futuro. É possível concluir que as células estaminais mesenquimais do tecido adiposo de cutias têm características biológicas e comportamentos in vitro que demonstram seu potencial para uso em testes clínicos.(AU)

Immunophenotyping, plasticity tests and nanotagging of stem cells derived from adipose tissue of wild rodent agouti (Dasyprocta prymnolopha) / Imunofenotipagem, testes de plasticidade e marcação com nanocristais de céluas-tronco derivadas de tecido adiposo em cutias

There is a growing interest in the study of unspecialized mesenchymal stem cells, for there are still some discussions about their in vitro behavior. Regenerative medicine is a science undergoing improvement which develops treatments as cell therapy using somatic stem cells. In several studies, adipose tissue is presented as a source of multipotent adult cells that has several advantages over other tissue sources. This study aimed to characterize and evaluate the tagging of mesenchymal stem cells from the agoutis adipose tissue (Dasyprocta prymonolopha), with fluorescent intracytoplasmic nanocrystals. Fibroblast cells were observed, plastic adherent, with extended self-renewal, ability to form colonies, multipotency by differentiation into three lineages, population CD90 + and CD45 - expression, which issued high red fluorescence after the tagging with fluorescent nanocrystals by different paths and cryopreserved for future use. It is possible to conclude that mesenchymal stem cells from agouti adipose tissue have biological characteristics and in vitro behavior that demonstrate its potential for use in clinical tests.(AU)

Há um interesse crescente no estudo das células estaminais mesenquimais, não especializadas, pois ainda existem algumas discussões sobre seu comportamento in vitro. A medicina regenerativa é uma ciência em fase de crescimento que desenvolve tratamentos como terapia celular utilizando células estaminais somáticas. Em vários estudos, o tecido adiposo é apresentado como uma fonte de células adultas multipotentes que tem várias vantagens em relação a outras fontes de tecido. Este estudo teve como objetivo caracterizar e avaliar a marcação de células estaminais mesenquimais do tecido adiposo de cutias (Dasyprocta prymnolopha) com nanocristais intracitoplasmáticos fluorescentes. Observaram-se células fibroblásticas, aderentes ao plástico, com autorrenovação prolongada, capacidade de formar colônias, diferenciação em três linhagens, população CD90 + e expressão CD45, que emitiram alta fluorescência vermelha após a marcação com nanocristais fluorescentes por diferentes vias, e criopreservadas para uso futuro. É possível concluir que as células estaminais mesenquimais do tecido adiposo de cutias têm características biológicas e comportamentos in vitro que demonstram seu potencial para uso em testes clínicos.(AU)

Canine lymphomas diagnosed in southern Brazil from 2000 to 2017: epidemiology and immunophenotype

ABSTRACT: Lymphoma is a neoplasm that originates from solid hematopoietic tissues and is one of the most common tumors in dogs. The goal of the present study was to perform a retrospective study of canine lymphomas diagnosed at the Laboratório Regional de Diagnóstico, at the Faculdade de Veterinária of the Universidade Federal de Pelotas (LRD-UFPel) from 2000 to 2017, to determine the epidemiology and anatomical distribution, and to evaluate the histopathological and immunohistochemical aspects of each case according to the adapted Kiel classification. The protocols for necropsies and biopsies in the laboratory were reviewed. Lymphoma was diagnosed in 77 dogs. Approximately 37.7% (29/77) of affected dogs had no defined breed, while dogs with defined breeds accounted for 58.4% (45/77) of the diagnoses. The occurrence in males (40/77) was slightly higher than that in females (36/77), and the mean age was 8.1 years (1.4-17 years). The most affected age group was between six and 10 years of age with 31 cases (40.2%). Regarding the anatomical classification, the multicentric form was the most prevalent, accounting for 71.4% (55/77) of the diagnoses. In 40 cases that immunophenotyping was performed, B-cell lymphomas represented 62.5% of the diagnoses (25/40), while T-cell lymphomas corresponded to 37.5% of the diagnoses (15/40). The degree of malignancy according to the modified Kiel classification was low in 35% of lymphomas (14/40) and high in 65% of cases (26/40). The multicentric form was more frequent in the region of influence of the LRD-UFPel. Identification of the immunophenotype can improve the quality of life and survival in affected dogs since it allows the most appropriate treatment for each patient.

RESUMO: O linfoma é uma neoplasia com origem nos tecidos hematopoiéticos sólidos e é um dos tumores mais frequentes em cães. O objetivo do presente trabalho foi efetuar um estudo retrospectivo dos linfomas caninos recebidos no Laboratório Regional de Diagnóstico, da Faculdade de Veterinária da Universidade Federal de Pelotas (LRD-UFPel) de 2000 a 2017, determinando a epidemiologia e a distribuição anatômica, bem como os aspectos histopatológicos e imuno-histoquímicos de cada caso de acordo com a classificação de Kiel adaptada. Foram revisados os protocolos de necropsias e biópsias recebidos no laboratório identificando-se 77 casos de cães com diagnóstico de linfoma. A doença afetou cães sem raça definida em 37,7% (29/77) dos casos, enquanto os cães com raças definidas tiveram 58,4% (45/77) dos diagnósticos. A ocorrência em machos (40/77) foi discretamente maior do que em fêmeas (36/77) e a idade média foi de 8,1 anos (1,4-17 anos). A faixa etária mais acometida foi entre seis e 10 anos de idade com 31 casos (40,2%). Quanto à classificação anatômica a forma multicêntrica foi a mais prevalente atingindo 71,4% (55/77) dos diagnósticos. Em 40 casos em que a imunofenotipagem foi realizada, os linfomas de células B representaram 62,5% dos casos (25/40), enquanto os linfomas de células T equivaleram a 37,5% dos diagnósticos (15/40). O grau de malignidade de acordo com a classificação de Kiel modificada foi baixo em 35% dos linfomas (14/40) e alto em 65% dos casos (26/40). Conclui-se que a forma multicêntrica é mais frequente na região de influência do LRD-UFPel e que a identificação do imunofenótipo pode melhorar a qualidade de vida e dar maior sobrevida aos cães afetados uma vez que permite o tratamento mais adequado para cada caso.

Hematological and immunological development from birth to six months of age in Holstein calves / Desenvolvimento hematológico e imunológico em bezerros Holandeses do nascimento aos seis meses de idade

The hematological and immunological development of calves from birth to 6 months of age was performed by hemogram and cellular phenotype. Ten male Holstein calves were assessed in 13 moments: before colostrum intake (D0), every 2 days until the 10th day of life (D2 to D10), at the 15th day after birth (D15), and then monthly up to 6 months (D180). Calves presented hemoconcentration on day (D) 0 and showed a gradual decrease in hematimetric rates until D180. The inversion of the neutrophilic for lymphocytic profile was observed on D4. The percentage of CD3+ cells on D10 was higher than D30 up to D180. The number of CD4+ and CD8+ cells did not change between time points. The number of CD21+ lymphocytes was significantly higher at early time points of D0 up to D15, compared on D30 until D150. In conclusion, the neonatal period was marked by stress leukogram in the first 4 days, and low number of B lymphocytes. These might be risk factors for bacterial infections responsible for navel inflammation and diarrhea. The increase in the number of B cells from 30 days of age demonstrated that the calves were functional and able to generate an immune response.(AU)

O desenvolvimento hematológico e o imunológico de bezerros do nascimento aos seis meses de idade foram avaliados por meio hemograma e imunofenotipagem dos linfócitos. Para tanto, 10 bezerros machos Holandeses foram avaliados em 13 momentos: antes da ingestão do colostro (D0), a cada dois dias até o 10º dia (D2 a D10), 15º dia (D15) e, em seguida, mensalmente até seis meses de idade (D180). Os bezerros apresentaram hemoconcentração em D0 e decréscimo gradual dos índices hematimétricos até D180. A inversão do perfil neutrofílico para linfocítico foi observada em D4. Os valores de CD3+ (%) em D10 foram maiores que aqueles observados em D30 até D180. CD4+ e CD8+ não apresentaram alterações entre os momentos. Os linfócitos B CD21+ aumentaram significativamente a partir dos primeiros momentos D0 até D15, em comparação com os momentos subsequentes D30 até D150. Em conclusão, o período neonatal foi caracterizado pelo leucograma de estresse nos primeiros quatro dias e o baixo número de linfócitos B. Esses fatos podem ser considerados como fatores de risco para infecções bacterianas responsáveis pelas inflamações umbilicais e pela diarreia. Por outro lado, o aumento de células B após os 30 dias de vida demonstrou que os bezerros foram capazes de gerar uma resposta imune.(AU)

Hematological and immunological development from birth to six months of age in Holstein calves / Desenvolvimento hematológico e imunológico em bezerros Holandeses do nascimento aos seis meses de idade

The hematological and immunological development of calves from birth to 6 months of age was performed by hemogram and cellular phenotype. Ten male Holstein calves were assessed in 13 moments: before colostrum intake (D0), every 2 days until the 10th day of life (D2 to D10), at the 15th day after birth (D15), and then monthly up to 6 months (D180). Calves presented hemoconcentration on day (D) 0 and showed a gradual decrease in hematimetric rates until D180. The inversion of the neutrophilic for lymphocytic profile was observed on D4. The percentage of CD3+ cells on D10 was higher than D30 up to D180. The number of CD4+ and CD8+ cells did not change between time points. The number of CD21+ lymphocytes was significantly higher at early time points of D0 up to D15, compared on D30 until D150. In conclusion, the neonatal period was marked by stress leukogram in the first 4 days, and low number of B lymphocytes. These might be risk factors for bacterial infections responsible for navel inflammation and diarrhea. The increase in the number of B cells from 30 days of age demonstrated that the calves were functional and able to generate an immune response.(AU)

O desenvolvimento hematológico e o imunológico de bezerros do nascimento aos seis meses de idade foram avaliados por meio hemograma e imunofenotipagem dos linfócitos. Para tanto, 10 bezerros machos Holandeses foram avaliados em 13 momentos: antes da ingestão do colostro (D0), a cada dois dias até o 10º dia (D2 a D10), 15º dia (D15) e, em seguida, mensalmente até seis meses de idade (D180). Os bezerros apresentaram hemoconcentração em D0 e decréscimo gradual dos índices hematimétricos até D180. A inversão do perfil neutrofílico para linfocítico foi observada em D4. Os valores de CD3+ (%) em D10 foram maiores que aqueles observados em D30 até D180. CD4+ e CD8+ não apresentaram alterações entre os momentos. Os linfócitos B CD21+ aumentaram significativamente a partir dos primeiros momentos D0 até D15, em comparação com os momentos subsequentes D30 até D150. Em conclusão, o período neonatal foi caracterizado pelo leucograma de estresse nos primeiros quatro dias e o baixo número de linfócitos B. Esses fatos podem ser considerados como fatores de risco para infecções bacterianas responsáveis pelas inflamações umbilicais e pela diarreia. Por outro lado, o aumento de células B após os 30 dias de vida demonstrou que os bezerros foram capazes de gerar uma resposta imune.(AU)

Cryopreservation of lymphocytes for immunological studies in horses / Criopreservação de linfócitos para estudos imunológicos em equinos

The use of frozen cells allows studies on diseases and other immunological assays, since it facilitates the logistics of collecting and transporting, including laboratories located in different cities or other countries. The objectives of this study were to verify if the storage in the refrigerator after collection at different times changes the viability of total leukocytes after months of freezing and the ratio of CD4/CD8 is affected by the freezing process. Venous blood of 15 healthy horses was used and the experiment was divided into 2 stages. In the first, the viability of the leukocytes before and after freezing was verified, as well as different storage times in the refrigerator (fresh blood, stored for 24 and 48 hours) before the freezing process. In the second part, the immunophenotyping of the T lymphocytes was performed, in order to observe if after thawing the relationship between LT CD4 and LT CD8 undergoes change. There was no difference between the amounts of viable leucocytes from frozen fresh blood compared to fresh blood before freezing, nor difference between the viability of blood left in the refrigerator (4°C) for 24 hours and fresh blood and fresh frozen blood. There was a decrease in viability of frozen leukocytes after 48 hours left in the freezer for other samples; however, the recovery was 107x cells. Regarding the immunophenotyping of CD2CD4+ and CD2CD8+ double-labeled T lymphocytes in the blood stored in the refrigerator for 24 hours before freezing, no difference was observed between before and after 6 months of freezing. It is concluded that cryopreservation of equine total leukocytes is possible and, although there was a difference between freezing times, even in the less viable sample, sufficient numbers of cells were recovered for other immunological assays.(AU)

A utilização de células congeladas possibilita estudos sobre doenças e outros ensaios imunológicos, pois facilita a logística de coleta e transporte, inclusive para laboratórios localizados em cidades diferentes ou outros países. Os objetivos desse estudo foram verificar se o armazenamento sobre refrigeração em diferentes tempos e a criopreservação alteram a viabilidade de leucócitos totais e se a relação entre LT CD4/CD8 é afetada pelo processo de congelamento. Utilizou-se sangue venoso de 15 cavalos hígidos e o experimento foi dividido em 2 etapas. Na primeira foi analisado se houve alteração na viabilidade dos leucócitos provenientes de amostras de sangue armazenadas em diferentes tempos em geladeira antes e depois de 6 meses de congelamento a -80°C. Na segunda parte, realizou-se a imunofenotipagem dos linfócitos T, com a finalidade de observar se após o descongelamento a relação entre LT CD4 e LT CD8 sofre alteração. Não houve diferença entre a quantidade de leucócitos viáveis da amostra de sangue fresco descongelado em relação ao sangue fresco antes do congelamento, nem diferença entre a viabilidade do sangue deixado em congelador (4°C) por 24 horas e do sangue fresco. Houve uma diminuição da viabilidade dos leucócitos, após o descongelamento de 6 meses (-80°C), das amostras de sangue deixado em geladeira por 48 horas antes do congelamento em relação às outras amostras, porém, a recuperação foi de células x107. Quanto à imunofenotipagem de linfócitos T com dupla marcação CD2CD4+ e CD2CD8+, no sangue armazenado em geladeira por 24 horas antes do congelamento, e não foi observada diferença entre antes ou depois de 6 meses de congelamento. Conclui-se que a criopreservação de leucócitos totais de equinos é possível e, embora tenha havido diferença entre os tempos de congelamento, mesmo na amostra menos viável, houve recuperação de uma quantidade de células suficientes para outros ensaios imunológicos.(AU)