Transcriptomic analysis of bone marrow specimens collected from Miniature Dachshunds diagnosed with non-neoplastic bone marrow disorders.

Non-neoplastic bone marrow disorders are main causes of non-regenerative anemia in dogs. Despite the high incidence of the diseases, their molecular pathophysiology has not been elucidated. We previously reported that Miniature Dachshund (MD) was a predisposed breed to be diagnosed with non-neoplastic bone marrow disorders in Japan, and immunosuppressive treatment-resistant MDs showed higher number of platelets and morphological abnormalities in peripheral blood cells. These data implied that treatment-resistant MDs might possess distinct pathophysiological features from treatment-responsive MDs. Therefore, we conducted transcriptomic analysis of bone marrow specimens to investigate the pathophysiology of treatment-resistant MDs. Transcriptomic analysis comparing treatment-resistant MDs and healthy control dogs identified 179 differentially expressed genes (DEGs). Pathway analysis using these DEGs showed that "Wnt signaling pathway" was a significantly enriched pathway. We further examined the expression levels of DEGs associated with Wnt signaling pathway and confirmed the upregulation of AXIN2 and CCND2 and the downregulation of SFRP2 in treatment-resistant MDs compared with treatment-responsive MDs and healthy control dogs. This alteration implied the activation of Wnt signaling pathway in treatment-resistant MDs. The activation of Wnt signaling pathway has been reported in human patients with myelodysplastic syndrome (MDS), which is characterized by dysplastic features of blood cells. Therefore, the results of this study implied that treatment-resistant MDs have distinct molecular pathological features from treatment-responsive MDs and the pathophysiology of treatment-resistant MDs might be similar to that of human MDS patients.

Gene expression profiles associated with early relapse during first remission induction in canine multicentric high-grade B-cell lymphoma.

Although chemotherapy using CHOP-based protocol induces remission in most cases of canine multicentric high-grade B-cell lymphoma (mhBCL), some cases develop early relapse during the first induction protocol. In this study, we examined the gene expression profiles of canine mhBCL before chemotherapy and investigated their associations with early relapse during the first whole CHOP-based protocol. Twenty-five cases of mhBCL treated with CHOP-based protocol as first induction chemotherapy were included in this study. Sixteen cases completed the first whole CHOP-based protocol without relapse (S-group), and nine developed relapse during the chemotherapy (R-group). RNA-seq was performed on samples from neoplastic lymph nodes. Differentially expressed genes (DEGs) were extracted by the comparison of gene expression profiles between S- and R-groups, and the differences in the expression levels of these genes were validated by RT-qPCR. Extracted 179 DEGs included the genes related to chemokine CC motif ligand, T-cell receptor signaling pathway, and PD-L1 expression and PD-1 checkpoint pathway. We focused on chemokine CC motif ligand, and CCL4 was confirmed to be significantly downregulated in the R-group (P=0.039). We also focused on the genes related to T-cell signaling pathway, and CD3E (P=0.039), ITK (P=0.023), and LAT (P=0.023) genes were confirmed to be significantly upregulated in the R-group. The current results suggest that both changes in tumor cells and the interactions between tumor cells and immune cells are associated with the efficacy of the chemotherapy for first remission induction.

Efficacy and adverse events of L-Asparaginase administration as a first-line treatment for feline large-cell gastrointestinal lymphoma.

L-Asparaginase (L-Asp) is often used to induce remission in feline large-cell gastrointestinal lymphoma (LCGIL). However, no study has evaluated the efficacy and adverse events following the initial use of this drug as a first-line treatment in feline LCGIL. We retrospectively reviewed medical records of cats with LCGIL treated with L-Asp to induce remission. This study included 43 cats. The response rate (RR) after the first administration of L-Asp was 37.2% (Complete remission: 7.0%, partial remission: 30.2%). RR was significantly higher in cases with primary gastric lesions (64.3%) than in those with primary intestinal lesions (24.1%) (P=0.018), and it was also higher in cases without anemia (57.1%) than those with anemia (15.0%) (P=0.009). The most common adverse event was hyperammonemia, which occurred in 10 of 12 cases where we could compare plasma ammonia concentrations before and after the first dose of L-Asp. Plasma phosphate concentrations were also significantly increased (P<0.001) within 24 hr after the first dose. Decreased appetite, vomiting, and diarrhea were also observed in five, three, and seven cases, respectively, and Grade 3 or higher gastrointestinal signs were observed as adverse events in three cases. The median overall survival of all cats was 150 days (range, 5-1,065 days), and the median progression-free survival was 104 days (range, 2-978 days). In conclusion, L-Asp was effective to induce remission, and severe adverse events were uncommon in feline LCGIL.

Clinical characteristics and outcomes of Mott cell lymphoma in nine miniature dachshunds.

BACKGROUND: Lymphoma with Mott cell change, or Mott cell lymphoma (MCL), is an uncommon variant of canine lymphoma. Because of its rare occurrence, there has been no comprehensive study describing the disease so far. Miniature dachshunds, a popular breed in Japan, sometimes experience MCL. OBJECTIVES: To investigate the clinical characteristics and outcomes of MCL in miniature dachshunds. METHODS: Medical records were retrospectively reviewed to identify miniature dachshunds diagnosed with MCL and other types of lymphoma. Data on clinical and laboratory findings, treatments and outcomes were collected. Survival times were compared between miniature dachshunds with MCL and other types of lymphoma. RESULTS: Of the 87 miniature dachshunds diagnosed with lymphoma, 9 (10%) had cytological characteristics of MCL. All 9 miniature dachshunds with MCL were categorised as having alimentary lymphoma (small and/or large intestine, 6 dogs; mesenteric lymph node, 3 dogs). The median age was 3.1 years (range, 2.0-9.4 years). All nine dogs were treated with chemotherapeutic protocols used for large cell lymphoma or alkylating agents such as melphalan or chlorambucil. The overall response rate to initial chemotherapy was 78%, and the median progression-free survival was 105 days. Overall survival in these nine dogs ranged from 6 to >1513 days (median, 240 days), which was significantly longer than in 29 miniature dachshunds with alimentary large cell lymphoma other than MCL (median, 57 days; p = 0.0491). CONCLUSIONS: MCL in miniature dachshunds can be recognised as a peculiar type of B-cell lymphoma occurring in relatively young dogs as an alimentary form and has a longer survival compared with typical alimentary large cell lymphoma.

Retrospective study of feline tracheal mass lesions.

OBJECTIVES: This multicentre, retrospective observational study aimed to describe the clinical presentation, diagnostic methods, treatment and outcomes of cats with tracheal masses. METHODS: Eighteen cats from five academic or secondary/tertiary animal hospitals were included. RESULTS: The median age at diagnosis was 10.7 years (mean 9.5; range 1-17). There were nine castrated males, seven spayed females, one intact male and one intact female. Fourteen (78%) were domestic shorthairs, one (6%) was an Abyssinian, one (6%) was an American Shorthair, one (6%) was a Bengal and one (6%) was a Scottish Fold. The most common presenting complaints included chronic respiratory distress or dyspnoea (n = 14), followed by wheezing/gagging (n = 12), coughing (n = 5) and voice changes (n = 5). There was cervical tracheal involvement in 16/18, and two showed involvement of the intrathoracic trachea. The following methods were used for diagnosis: ultrasound-guided fine-needle biopsy (UG-FNB) and cytology (n = 8), bronchoscopic forceps biopsy and histopathology (n = 5), surgical resection and histopathology (n = 3), forceps biopsy via an endotracheal tube (n = 1) and histology of tissue sputtered from a cough (n = 1). Lymphoma was most often diagnosed (n = 15), followed by adenocarcinoma (n = 2) and squamous cell carcinoma (n = 1). Most lymphoma cases received chemotherapy with or without radiation according to various protocols, and partial (n = 5) or complete responses (n = 8) were noted. Kaplan-Meier survival data for cats with lymphoma revealed a median survival time of 214 days (95% confidence interval >149 days), which was significantly longer than that of other types of tumours (21 days). CONCLUSIONS AND RELEVANCE: Lymphoma was the most prevalent diagnosis, and showed a good response to chemotherapy with or without radiation therapy. Various diagnostic procedures were performed, and UG-FNB and cytology are good diagnostic procedures for cervical tracheal lesions. Owing to the variety of treatment protocols at different centres, it was impossible to compare outcomes.

Serum level of apoptosis inhibitor of macrophage in dogs with histiocytic sarcoma and its association with the disease.

Histiocytic sarcoma (HS) is a rare neoplasm of macrophages or dendritic cells with a poor prognosis in dogs. As the apoptosis inhibitor of macrophage (AIM) is characteristically expressed in canine macrophages, we hypothesised that AIM is involved in the development or progression of HS in dogs. In this study, AIM expression in the tumour region and serum AIM levels in dogs with HS was assessed. Additionally, the effects of AIM overexpression on HS cell viability were investigated using a HS cell line that was selected from five validated HS cell lines. Immunohistochemistry showed that AIM expression was observed in the cytoplasm of the HS cells. CD36, a candidate AIM receptor, was also observed on the cell membrane of HS cells. When the serum AIM level was detected in 36 dogs with HS and 10 healthy dogs via western blot analysis, the AIM levels in the HS dogs were significantly higher than those in the controls. AIM mRNA expression in the 5 HS cell lines varied but was higher than that in the other tumour-derived lines. Among the five HS cell lines, DH82 originally had lower AIM and the highest CD36 expression. When AIM was overexpressed in DH82, therein cell growth speed and invasion, apoptosis inhibition and phagocytic activity were strongly upregulated. These data suggest that elevated intra-tumour expression of AIM could induce the progression of HS cells in dogs. Moreover, elevated serum AIM levels in dogs with HS could serve as a biomarker of HS.

Successful treatment of a lung abscess without surgical intervention in a cat.

Case summary: An 8-year-old neutered female domestic shorthair cat was referred with complaints of lethargy, anorexia, fever, tachypnoea and a pulmonary mass on thoracic radiography. Whole-body CT revealed the presence of a nodular lesion in the right caudal lobe of the lung. Fine-needle aspiration of the lung mass yielded purulent fluid and cytology showed a large number of mildly to moderately degenerated neutrophils with numerous cocci and bacilli, leading to the diagnosis of a lung abscess. Empirical administration of doxycycline and orbifloxacin was initiated on the day of referral. Bacterial culture and antibiotic susceptibility tests using the collected fluid sample detected two types of bacteria, which were susceptible to both antibiotics. The clinical signs of the cat improved after the initiation of treatment, and the antibiotics were discontinued 28 days later, after the lung lesions disappeared. No recurrence of lung abscess was observed until 588 days after the discontinuation of treatment. Relevance and novel information: Only one case of a lung abscess has been previously reported in cats. Furthermore, while surgical resection is the most common treatment for lung abscesses in the field of veterinary medicine, this is the first report of successful treatment with antibiotic administration alone.

Efficacy and adverse events of continuous l-asparaginase administration for canine large cell lymphoma of presumed gastrointestinal origin.

We examined the efficacy and adverse events of continuous l-asparaginase administration in dogs with large cell lymphoma of presumedgastrointestinal (GI) origin. We retrospectively reviewed medical records of dogs with large cell lymphoma of presumed GI origin treated with continuous l-asparaginase administration from 2009 to 2018. We collected information on the signalment, lesion site, complete blood count, serum biochemical profile, diagnostic imaging findings, cytological and histopathological findings, immunophenotype, l-asparaginase administration frequency, treatment response, adverse events, rescue protocol, and patient outcomes. Clinical outcomes were assessed using medical records or by contacting the owner or referring veterinarian. Thirty-two dogs with large cell lymphoma of presumed GI origin received weekly l-asparaginase administration. The median number of l-asparaginase injections was seven (range: 1-30). Although two of the 32 dogs had GI toxicity of grade 3 or higher, none developed a hypersensitivity reaction. The response rate based on ultrasonographic findings was 18/32 (56%) and that based on clinical signs was 30/32 (94%). The median overall progression-free survival was 50 days (range: 2-214 days), and median overall survival was 147 days (range: 2-482 days). Adverse events associated with continuous l-asparaginase administration were rare. Clinical signs at diagnosis improved in most cases. Based on these results, continuous l-asparaginase administration appears to be a reasonable treatment option for dogs with large cell lymphoma of presumed GI origin.

Outcomes and prognostic factors in canine epitheliotropic and nonepitheliotropic cutaneous T-cell lymphomas.

Canine cutaneous lymphoma is an uncommon lymphoma in dogs. Most canine cutaneous lymphoma cases have a T-cell origin. Canine cutaneous T-cell lymphoma (CTCL) is classified into epitheliotropic and nonepitheliotropic cutaneous lymphomas, and each type of lymphoma is subclassified into several histological subtypes. Limited information is available regarding the prognostic significance of clinical variables and histopathological subtypes in dogs with CTCL. This retrospective study aimed to investigate the influence of clinical variables and histopathological subtypes on the prognosis of dogs with CTCL. Forty-six dogs diagnosed with CTCL by histopathological examination were included. Histopathological specimens were reexamined and classified into CTCL subtypes. The influence of the type of skin lesion, histopathological subtype, haematological examination results and treatment response on the overall survival time (OS) was examined. Thirty-one dogs were diagnosed with epitheliotropic CTCL (mycosis fungoides in 28 dogs; pagetoid reticulosis in 3 dogs) and 15 dogs were diagnosed with nonepitheliotropic CTCL (anaplastic large T-cell lymphoma in 6 dogs; peripheral T-cell lymphoma, not otherwise specified, in 9 dogs). The OS of dogs diagnosed with epitheliotropic CTCL (141 days) was significantly shorter than that of dogs diagnosed with nonepitheliotropic CTCL (374 days). As clinical variables, the presence of neoplastic lymphocytes in peripheral blood, thrombocytopenia and initial chemotherapeutic response was related to prognosis. Our results demonstrated that histopathological subtype and several clinical variables were found to influence the prognosis of dogs with CTCL.

A retrospective study in 21 Shiba dogs with chronic enteropathy.

We retrospectively studied the clinical and laboratory features and outcomes of chronic enteropathy in Shiba dogs. Among 99 dogs with chronic enteropathy, 21 Shiba dogs (21%) were included in the study (odds ratio, 7.14). No significant differences were seen in signalment, clinical signs, symptoms or laboratory profiles between the Shiba and non-Shiba groups. Severe histopathological lesions in the duodenum were a common finding in the Shiba group. The median overall duration of survival in the Shiba group was 74 days, while that of the dogs in the non-Shiba group could not be determined because more than half of the cases remained alive at the end of this study. The difference between the groups was statistically significant (P<0.0001). The 6-month and 1-year survival rates for the Shiba group were 46% and 31%, respectively. Conversely, the 6-month, 1-year and 3-year survival rates for the non-Shiba group were 83%, 74% and 67%. The results obtained here demonstrated that the Shiba dog is predisposed to chronic enteropathy and shows severe duodenum lesions and poor outcomes, indicating a breed-specific disease.

Clinical and histopathological features and prognosis of gastrointestinal adenocarcinomas in Jack Russell Terriers.

There has been an increase in the number of Jack Russell Terriers (JRTs) diagnosed with adenomas and adenocarcinomas of the gastrointestinal tract in Japan. This study retrospectively investigated the clinical and histopathological features and prognosis of adenocarcinomas arising in the gastrointestinal tract in JRT dogs. Seven JRTs and 39 dogs of other breeds diagnosed with gastrointestinal adenocarcinoma were included in the study. The most common sites of gastrointestinal adenocarcinoma in JRTs were the pylorus and rectum. On histopathological examination, these adenocarcinomas showed a papillary or tubular growth pattern, and the lesions were confined within the mucosal epithelium and poorly invasive. Among all dogs with gastric adenocarcinoma, the median survival time (MST) for five of the JRTs could not be determined because more than half of the cases remained alive, while the MST for nine non-JRT dogs was 34 days. Among all dogs with adenocarcinoma in the large intestine, the MST for three of the JRTs could not be determined, while the MST for nine non-JRT dogs was 1,973 days. The difference in MST between JRT and non-JRT dogs with gastric adenocarcinoma was significant (P=0.0220). Since gastrointestinal adenocarcinomas in JRTs show distinct characteristics with respect to their clinical features, treatment course, and prognosis, a different surgical and medical treatment plan should be considered compared to the management of gastrointestinal adenocarcinomas in other dog breeds.

Efficacy of chemotherapy and palliative hypofractionated radiotherapy for cats with nasal lymphoma.

Nasal lymphoma (NL) is the most common nasal tumor in cats, and radiotherapy, chemotherapy, or a combination of these treatments have been described as the treatment for this disease. However, the previous studies included various machines and protocols of radiotherapy. Therefore, we aimed to retrospectively compare the prognosis among cases treated with palliative hypofractionated radiotherapy, chemotherapy, and a combination of them with united machine and protocol of radiotherapy. When compared overall survival and progression free survival, there was no significant difference among these three groups. The data of this study suggested that similar efficacy could be achieved by palliative hypofractionated radiotherapy, chemotherapy, or a combination of them.

Changes in the coagulation parameters in dogs with protein-losing enteropathy between before and after treatment.

Protein-losing enteropathy (PLE) is known to induce hypercoagulability and resultant thromboembolism in dogs. We hypothesized that hypercoagulability would improve if remission was obtained in dogs with PLE after treatment. This study aimed to evaluate the changes in the coagulation parameters after treatment in dogs diagnosed with PLE. As coagulation parameters, prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, thrombin-antithrombin complex (TAT), D-dimer, and antithrombin (AT) were measured. In addition to these parameters, rotational thromboelastometry (ROTEM), which evaluates the comprehensive coagulation and fibrinolysis reactions of whole blood, was conducted and the data of clotting time (CT), clot formation time (CFT), α angle (α), maximum clot firmness (MCF) and lysis index at 60 min (LI60) were obtained. Eleven of the 14 dogs diagnosed with PLE were classified as responders to the treatment based on the changes in their plasma albumin (ALB) concentration after treatment. Significant increase in CFT and decrease of α and MCF indicating the resolution of hypercoagulability were found after treatment in responder dogs; however, there was no significant change in the coagulation and fibrinolysis parameters other than those measured by ROTEM. This study demonstrated that the hypercoagulability detected by ROTEM was significantly improved after treatment in dogs with PLE.

Clinical and clinicopathological features and outcomes of Miniature Dachshunds with bone marrow disorders.

Non-neoplastic bone marrow disorders such as non-regenerative immune-mediated anemia, pure red cell aplasia, and myelodysplastic syndrome are major causes of non-regenerative anemia in dogs. However, there has been no study on the clinical and clinicopathological features of canine non-neoplastic bone marrow disorders in Japan. Hence, we first investigated the breed disposition of non-neoplastic bone marrow disorders that induce anemia as a retrospective study and found that Miniature Dachshund (MD) was a predisposed breed. Based on this finding, we investigated the clinical and clinicopathological features of non-neoplastic bone marrow disorders in MDs as a preliminary retrospective study, and we compared them between immunosuppressive treatment-responsive and -resistant MDs. We found that treatment-resistant MDs showed thrombocytosis and increased frequencies of dysplastic features in the peripheral blood. These results indicate that bone marrow disorders in treatment-resistant MDs might manifest distinct features compared with those in treatment-sensitive MDs, and sensitivity to immunosuppressive treatments could be predicted based on thrombocytosis and dysplastic features in the peripheral blood. Further studies that examine aberrations in the genome are needed to elucidate the pathophysiology of bone marrow disorders in MDs.

Treatment with rivaroxaban and monitoring of coagulation profiles in two dogs with venous thromboembolism.

Two dogs with immune-mediated hemolytic anemia complicated with thromboembolism were presented. Both of the dogs were initially treated with immunosuppressive therapy in conjunction with dalteparin and clopidogrel. Although the immunosuppressive therapy was effective, peritoneal effusion due to thromboembolism was observed during the course of the disease in these dogs. After initiation of rivaroxaban treatment, peritoneal effusion decreased immediately in parallel with the normalization of D-dimer, antithrombin (AT), and thrombin-antithrombin complex (TAT). Hematochezia, cutaneous hemorrhage, and hematuria were observed as adverse events after administration of rivaroxaban in one case. Rivaroxaban was effective for the control of thromboembolism secondary to immune-mediated hemolytic anemia, and D-dimer, AT, and TAT were useful to monitor the status of thromboembolic disease in dogs.

Evaluation of an automated point-of-care test system for measuring thrombin-antithrombin complex in dogs.

OBJECTIVE: To evaluate the utility of the chemiluminescent enzyme immunoassay (CLEIA) method for point-of-care (POC) measurement of canine plasma thrombin-antithrombin complex (TAT) concentration. ASSESSMENT AND MAIN RESULTS: Plasma TAT concentration was measured in 54 healthy dogs and in 72 dogs with various diseases. A significant correlation was found between TAT concentration measured by CLEIA and that measured by an ELISA that was previously used in dogs. The upper limit of the reference value of TAT concentrations measured by CLEIA was determined to be 0.2 ng/mL based on the TAT concentration in 54 healthy dogs. TAT concentrations exceeded the reference interval in a portion of dogs when a hypercoagulable state may be present. CONCLUSIONS: Canine plasma TAT concentrations measured using CLEIA were correlated with that measured using ELISA. Hence, a POC testing instrument may be used for early detection of activation of thrombin generation in emergency and critical care settings.

Time-course monitoring of serum amyloid A in a cat with pancreatitis.

Time-course changes in the concentration of serum amyloid A (SAA), a major acute phase protein, were measured in a cat with pancreatitis over an 831-day period and compared with changes in WBC count and feline trypsin-like immunoreactivity (fTLI). SAA concentration was increased at the onset of the disease and gradually decreased over 5 days of treatment with an improvement in the clinical condition. In contrast, fTLI concentration and WBC count were not increased at the onset of the disease but increased gradually during the 5 days of treatment. Long-term monitoring from days 68 to 831 revealed a good correlation between SAA concentration and the reoccurrence of clinical signs in the cat; however, WBC count did not increase even with the exacerbation of disease. These findings suggest that the SAA concentration may be a useful marker for evaluating response to treatment and disease exacerbation in feline pancreatitis.

Blastic natural killer cell lymphoma/leukaemia in a cat.

CASE SUMMARY: A 7-year-old mixed-breed cat presented with subcutaneous oedema and erythema extending from the right axilla to the abdomen. Fine-needle aspiration of the subcutaneous lesion revealed large, atypical, round cells. A clonality analysis for the T-cell receptor-gamma and immunoglobulin heavy chain genes showed no clonal rearrangement. The presumed diagnosis was lymphoma and the cat was treated with prednisolone and L-asparaginase but died 78 days after initial treatment. At necropsy, an oedematous subcutaneous mass in the right axilla, hepatomegaly, splenomegaly and lymphadenopathy of the mediastinum and left axilla were observed. Histopathological examination revealed diffuse infiltration of large atypical round cells in the subcutaneous mass, liver, spleen, lymph nodes and bone marrow. Immunohistochemically, the tumour cells were strongly positive for CD56, and negative for CD3, CD20, CD79a, CD57, granzyme B and perforin. Based on these findings, the cat was diagnosed with blastic natural killer (NK) cell lymphoma/leukaemia. RELEVANCE AND NOVEL INFORMATION: Here, we report the pathological and clinical findings of NK cell lymphoma/leukaemia in a cat. The antibody for human CD56, a diagnostic marker for human NK cell neoplasms, showed cross-reactivity with feline CD56 by immunohistochemistry and Western blotting analysis. The antibody could be a useful diagnostic marker for feline NK cell neoplasms.

Establishment of cell line and in vivo mouse model of canine Langerhans cell histiocytosis.

A cell line named FB-LCH01, derived from a dog diagnosed with Langerhans cell histiocytosis (LCH), was established and characterized. FB-LCH01 had C-shaped nucleoli, characterized by modal chromosome aberrations. The original tumour cells as well as established FB-LCH01 cells were immunopositive for human leukocyte antigen-DR, Iba-1 and E-cadherin, and immunonegative for CD163 and CD204, suggesting Langerhans cell origin. Furthermore, the characteristics of FB-LCH01 were compared with those of two canine histiocytic sarcoma cell lines (PWC-HS01 and FCR-HS02) established previously. Expression of E-cadherin was detected only in FB-LCH01, but not in PWC-HS01 and FCR-HS02. All (n = 9) the severe combined immunodeficiency mice inoculated with the FB-LCH01 cells developed subcutaneous tumour masses after 3 weeks. Eight of nine mice also developed metastatic lesions in the lymph nodes (8/8; 100%), lung (5/8; 62.5%), stomach (5/8; 62.5%), heart (4/8; 50%), pancreas (4/8; 50%), kidney (3/8; 37.5%), skin (3/8; 37.5%) and bone marrow (1/8; 12.5%). Tumour cells were pleomorphic and round- to polygonal-shaped with prominent anisocytosis and anisokaryosis. The xenotransplanted tumour cells maintained the immunohistochemical features of the original tumour with persistent E-cadherin expression at injection site and some visceral organs. In conclusion, the established cell line as well as the mice xenotransplant model in this study reflect the nature of canine LCH and may serve as promising models for investigating the patho-tumorigenesis and therapy of the disease.

Verification of measurement of the feline serum amyloid A (SAA) concentration by human SAA turbidimetric immunoassay and its clinical application.

Serum amyloid A (SAA) is one of the major acute phase proteins in cats that has potential to be used as an inflammatory marker. A previous study showed that the human SAA turbidimetric immunoassay (hSAA-TIA) could be used to measure the SAA concentration in cats. The objectives of the present study were to assess use of hSAA-TIA for determining the feline SAA concentration and to evaluate its clinical application. Recombinant feline SAA protein (rfSAA) was expressed in Escherichia coli and purified for SDS-PAGE and immunoblot analysis with anti-human SAA antibodies. The concentration of rfSAA was determined by ELISA and hSAA-TIA. Plasma SAA concentrations were measured in healthy and diseased cats by hSAA-TIA. The time-courses changes in the SAA and alpha1-acid glycoprotein (AGP) concentrations in the cats after ovariohysterectomy were investigated. In SDS-PAGE, rfSAA was detected as a clear band that reacted with anti-human SAA antibodies. There was significant correlation between the SAA concentration measured by ELISA and hSAA-TIA. The SAA concentration of the diseased cats (n=263) was significantly increased (P<0.01; 0.0-88.9 mg/l, mean: 7.52 mg/l) compared with that in the healthy cats (n=26; 0.0-0.9 mg/l, mean: 0.14 mg/l). No correlation was observed between SAA and WBC in the diseased cats. The SAA concentration changed more rapidly and remarkably than the AGP concentration after ovariohysterectomy. The present study revealed that hSAA-TIA is useful for determination of the feline SAA concentration. Measurement of the SAA concentration, in addition to the WBC count, would be clinically valuable as a routine test to detect inflammation.