Involvement of peripheral mast cells in a fibromyalgia model in mice.

Fibromyalgia is a painful disorder of unknown aetiology that presents activation and recruitment of innate immune cells, including mast cells. Efforts have been made to understand its pathogenesis to manage it better. Thus, we explored the involvement of peripheral mast cells in an experimental model of fibromyalgia induced by reserpine. Reserpine (1 mg/kg) was subcutaneously (s.c.) injected once daily in the back of male Swiss mice for three consecutive days. We analysed mechanical and cold allodynia, muscle fatigue and number of mast cell in plantar tissue. The fibromyalgia induction produced mast cell infiltration (i.e., mastocytosis) in the mice's plantar tissue. The depletion of mast cell mediators with the compound 48/80 (0.5-4 mg/kg, intraperitoneal (i.p.)) or the mast cell membrane stabilizer ketotifen fumarate (10 mg/kg, oral route (p.o.) widely (80-90 %) and extensively (from 1 up to 10 days) prevented reserpine-induced mechanical and cold allodynia and muscle fatigue. Compound 48/80 also prevented the reserpine-induced mastocytosis. Finally, we demonstrated that PAR-2, 5-HT2A, 5-HT3, H1, NK1 and MrgprB2 receptors, expressed in neuronal or mast cells, seem crucial to mediate fibromyalgia-related cardinal symptoms since antagonists or inhibitors of these receptors (gabexate (10 mg/kg, s.c.), ENMD-1068 (10 mg/kg, i.p.), ketanserin (1 mg/kg, i.p.), ondansetron (1 mg/kg, p.o.), promethazine (1 mg/kg, i.p.), and L733,060 (5 mg/kg, s.c.), respectively) transiently reversed the reserpine-induced allodynia and fatigue. The results indicate that mast cells mediate painful and fatigue behaviours in this fibromyalgia model, representing potential therapy targets to treat fibromyalgia syndrome.

[Characterization of patients with anaphylaxis in a tertiary hospital in Medellin, Colombia (2009-2019)]. / Identificación de pacientes con anafilaxia en una institución de salud de tercer nivel de Medellín, Colombia (2009-2019).

OBJECTIVE: To characterize demographically and clinically the patients with anaphylaxis treated in a third level health institution in Medellin, Colombia. METHODS: A cross-sectional descriptive observational study was carried out, which includedpatients were diagnosed with anaphylaxis between 2009 and 2019. Information was retrieved from medical records through a collection instrument. Subsequently, a descriptive statistical analysis of proportions and measures of central tendency of the variables of interest was performed. RESULTS: A total of 1820 records were reviewed and data from 253 patients were included. Among the reported comorbidities, drug allergy was the most prevalent (28%). The most frequent manifestations of anaphylaxis were cutaneous and respiratory. Most of the cases presented basal tryptase values ≤ 11.4 ng/mL (94.7%). Different etiological agents (food, drugs, insects and latex) were reported, and their frequency varied according to age. Adrenaline, steroids, and antihistamines were the treatments of choice in 39.9, 34.3, and 39.9% of cases, respectively. CONCLUSIONS: The characteristics of anaphylaxis in a medical center in Colombia coincide with those reported in Latin American. The treatment of anaphylaxis is not standardized, which makes it necessary to educate the health personnel and develop national guidelines.

OBJECTIVO: Identificar las características clínicas y demográficas de pacientes con anafilaxia, atendidos en un hospital de tercer nivel de Medellín, Colombia. MÉTODOS: Estudio observacional, descriptivo, de corte transversal, al que se incluyeron pacientes con diagnóstico con anafilaxia entre 2009 y 2019. La información de los pacientes se obtuvo a partir de los expedientes clínicos, mediante un instrumento de recolección. Se realizó un análisis estadístico descriptivo, de proporciones y medidas de tendencia central de las variables de interés. RESULTADOS: Se revisaron 1820 expedientes y se incluyeron los datos de 253 pacientes. Los agentes etiológicos más frecuentes fueron: medicamentos (52.1%), alimentos (34.7%), picadura de insectos (13.8%) y agentes no especificados (17.7%). Las manifestaciones cutáneas y respiratorias fueron las más frecuentes asociadas con anafilaxia. El 94.7% de los casos tuvo concentraciones normales de triptasa. La adrenalina, los corticosteroides y antihistamínicos fueron los fármacos de elección en el 39.9, 34.3 y 39.9% de los casos, respectivamente. CONCLUSIONES: Las características de anafilaxia coinciden con las reportadas en la mayor parte de los estudios en Latinoamérica. Aunque existen guías mundiales de tratamiento de la anafilaxia, no suelen aplicarse de forma uniforme, lo que hace necesario adiestrar al personal de salud y desarrollar guías nacionales al respecto.

Assessment of Bone Microarchitecture in Patients with Systemic Mastocytosis and its Association with Clinical and Biochemical Parameters of the Disease.

Patients with systemic mastocytosis (SM) are at high risk of bone deterioration. However, the evaluation of bone microarchitecture in this disease remains unclear. We aimed to assess bone microarchitecture in patients with SM. This was a cross-sectional study of 21 adult patients with SM conducted in a quaternary referral hospital in Sao Paulo, Brazil. A healthy, age-, weight-, and sex-matched cohort of 63 participants was used to provide reference values for bone microarchitecture, assessed by high resolution peripheral quantitative computed tomography (HR-pQCT). Total volumetric bone mineral density (vBMD), cortical vBMD, and cortical thickness at the radius were significantly lower in the control group compared with the SM group (all P < 0.001). Patients with aggressive SM had significantly lower trabecular number (Tb.N) (P = 0.035) and estimated failure load (F.load) (P = 0.032) at the tibia compared with those with indolent SM. Handgrip strength was significantly higher in patients who had more Tb.N at the radius (ρ, 0.46; P = 0.036) and tibia (ρ, 0.49; P = 0.002), and lower who had more trabecular separation at the radius (ρ, -0.46; P = 0.035) and tibia (ρ, -0.52; P = 0.016). Strong and positive associations between F.load (ρ, 0.75; P < 0.001) and stiffness (ρ, 0.70; P < 0.001) at the radius, and between F.load at the tibia (ρ, 0.45; P = 0.038) were observed with handgrip strength. In this cross-sectional study, aggressive SM was more susceptible to bone deterioration compared with indolent SM. In addition, the findings demonstrated that handgrip strength was associated with bone microarchitecture and bone strength.

Segurança da vacinação contra a COVID-19 em doentes referenciados dos cuidados de saúde primários por alergia ao veneno de himenópteros / COVID-19 vaccination safety in patients with hymenoptera venom allergy referred by primary health care

Introdução: As reações de hipersensibilidade após vacinação contra a COVID-19 têm vindo a ser descritas, embora a anafilaxia seja rara. A hipersensibilidade ao veneno de himenópteros constitui a terceira causa mais frequente de anafilaxia em Portugal, embora não pareça aumentar o risco de anafilaxia à vacinação contra a COVID-19. Objetivos: Avaliar a segurança da vacinação contra a COVID-19 em doentes com história de alergia ao veneno de himenópteros referenciados dos Cuidados de Saúde Primários (CSP). Métodos: Estudo observacional retrospectivo com inclusão dos doentes com alergia ao veneno de himenópteros referenciados pelos CSP ao serviço de Imunoalergologia, para estratificação do risco de reações de hipersensibilidade à vacina contra o SARS-CoV-2, entre janeiro e dezembro de 2021. Resultados: No total, incluíram-se 18 doentes, 72% do sexo feminino, média de idades de 61±18 [21-89] anos. Na caracterização do tipo da reação ao veneno de himenópteros, as reações locais exuberantes corresponderam a 33% de todas as reações referidas. Quanto a sintomas sistêmicos de anafilaxia, foram referidos sintomas mucocutâneos (33%), respiratórios (28%), cardiovasculares (33%) e gastrointestinais (11%). A abelha foi o inseto mais frequentemente implicado (61%). Relativamente aos valores de triptase basal, 3 doentes apresentaram níveis acima do cut-off estabelecido de 11,4 ng/mL, tendo indicação formal para iniciar esquema de vacinação em meio hospitalar. Durante o processo vacinal registrou-se um total de 46 administrações em 18 doentes, todas sem intercorrências. Apenas 5 doentes foram vacinados em meio hospitalar, tendo sido os restantes encaminhados para os CSP. Os doentes com mastocitose confirmada ou suspeita foram submetidos à pré-medicação com anti-histamínico anti-H1 e anti- H2, bem como montelucaste, na véspera e no dia da vacinação. Conclusões: A vacinação contra a COVID-19 é segura em doentes com reação de hipersensibilidade ao veneno de himenópteros. O protocolo utilizado mostrou ser eficaz na segregação de doentes entre CSP e cuidados secundários/terciários.

Introduction: Despite numerous reports of hypersensitivity reactions to COVID-19 vaccination, anaphylaxis is rare. Although hypersensitivity reactions to hymenoptera venom are the third most common cause of anaphylaxis in Portugal, they don't appear to enhance the risk of anaphylactic reaction to COVID-19 vaccination. Objectives: To assess the safety of COVID-19 vaccination in patients with a history of hymenoptera venom allergy. Methods: This retrospective observational study included patients with hymenoptera venom allergy referred by primary health care to the Immunoallergology Outpatient Clinic of a tertiary hospital between January and December 2021 to stratify the risk of hypersensitivity reactions to the SARSCoV- 2 vaccine. Results: A total of 18 patients were included: 72% women; mean age 61 (SD, 18 [range 21-89]) years. One-third of all reported reactions to hymenoptera venom were large and local. Topical systemic symptoms of anaphylaxis were mucocutaneous (33%), respiratory (28%), cardiovascular (33%) and gastrointestinal (11%). The honeybee was the most frequently involved hymenoptera species (61%). The basal tryptase levels of 3 patients were above the established cut-off (11.4 ng/mL) and they were formally indicated for vaccination in a hospital setting. Concerning the vaccination process, 46 doses were administered to the 18 patients and no reactions were recorded. Only 5 patients were vaccinated in a hospital environment; the rest were referred to primary health care centers. Patients with confirmed or suspected mastocytosis were premedicated with anti-H1 and anti-H2 antihistamines, as well as montelukast, the day before and on the day of vaccination. Conclusions: COVID-19 vaccination is safe for patients with hypersensitivity to hymenoptera venom. The risk assessment protocol effectively designated patients to primary or secondary/tertiary health care.

Leishmania major-Infected Phlebotomus duboscqi Sand Fly Bites Enhance Mast Cell Degranulation.

Leishmania parasites infect mammalian hosts through the bites of sand fly vectors. The response by mast cells (MC) to the parasite and vector-derived factors, delivered by sand fly bites, has not been characterized. We analyzed MC numbers and their mediators in BALB/c mice naturally infected in the ear with Leishmania major through the bite of the sand fly vector Phlebotomus duboscqi and compared them to non-infected sand fly bites. MC were found at the bite sites of infective and non-infected sand flies throughout 48 h, showing the release of granules with intense TNF-α, histamine, and tryptase staining. At 30 min and 48 h, the MC numbers were significantly higher (p < 0.001) in infected as compared to non-infected bites or controls. Neutrophil recruitment was intense during the first 6 h in the skin of infected and non-infected sand fly bites and decreased thereafter. An influx of neutrophils also occurred in lymph nodes, where a strong TNF-α stain was observed in mononuclear cells. Our data show that MC orchestrate an early inflammatory response after infected and non-infected sand fly bites, leading to neutrophilic recruitment, which potentially provides a safe passage for the parasite within the mammalian host.

Neuroendocrine apendicopathy in morphologically normal appendices of patients with diagnosis of acute appendicitis: Diagnostic study.

BACKGROUND: About 15%-25% of appendices removed to treat acute appendicitis present normal macro- and macroscopic morphology. The objective of this study was to verify an association of proinflammatory, neuroendocrine and immune mediators with morphologically normal appendices removed from patients with clinical laboratorial and imaging characteristics of acute appendicitis. MATERIALS AND METHODS: Appendices removed from 121 adult patients of both genders were distributed into three groups according to their following characteristics: group 1: 53 macro- and microscopically normal appendices from patients with clinical, laboratorial and imaging diagnosis of acute appendicitis; group 2: 24 inflamed appendices from patients with clinical, laboratorial, imaging and histopathological diagnosis of acute appendicitis; group 3: 44 normal appendices from patients submitted to right colectomy to treat localized ascending colon adenocarcinoma. All appendices were immunohistochemically studied for gastrin inhibitor peptide, mast cell tryptase, vascular endothelial growth factor; intestinal vasoactive peptide, tumor necrosis factor alpha, interleukin 1, prostaglandin E2, gene-protein product 9.5, CD8 T lymphocytes, synaptophysine, enolase, and S100 protein. RESULTS: The group 1 revealed increased levels of synaptophysine, enolase, mast cell tryptase and PGP-9.5 comparing with the other two groups. The group 2 presented increased levels of interleukin 1, CD8 T lymphocytes and prostaglandin E2 comparing with the other two groups. The group 3 confirmed the normal levels of all these neuroendocrine, immune and proinflammatory mediators. CONCLUSIONS: Morphologically normal appendices removed from patients with clinical and complementary exams indicating acute appendicitis have appendicular neuroimmunoendocrine disorder associated with the mediators synaptophysin, enolase, mast cell-related tryptase and gene-protein product 9.5.

Mast Cells in the Tumor Microenvironment.

Mast cells are tissue-resident, innate immune cells that play a key role in the inflammatory response and tissue homeostasis. Mast cells accumulate in the tumor stroma of different human cancer types, and increased mast cell density has been associated to either good or poor prognosis, depending on the tumor type and stage. Mast cells play a multifaceted role in the tumor microenvironment by modulating various events of tumor biology, such as cell proliferation and survival, angiogenesis, invasiveness, and metastasis. Moreover, tumor-associated mast cells have the potential to shape the tumor microenvironment by establishing crosstalk with other tumor-infiltrating cells. This chapter reviews the current understanding of the role of mast cells in the tumor microenvironment. These cells have received much less attention than other tumor-associated immune cells but are now recognized as critical components of the tumor microenvironment and could hold promise as a potential target to improve cancer immunotherapy.

Abordagem das reações de hipersensibilidade perioperatória: Orientações da Sociedade Brasileira de Anestesiologia e da Associação Brasileira de Alergia e Imunologia - Parte II: etiologia e diagnóstico / Approach to perioperative hypersensitivity reactions: Guidelines from the Brazilian Society of Anesthesiology and the Brazilian Association of Allergy and Immunology - Part II: etiology and diagnosis

A anafilaxia perioperatória é manifestação importante no contexto de eventos adversos relacionados à cirurgia. Embora frequentemente relacionada à indução anestésica, pode ocorrer por outros agentes administrados por outras vias. A anafilaxia pode se apresentar como colapso cardiovascular, obstrução da via aérea e/ou insuficiência respiratória com ou sem manifestação cutânea, com consequências fatais em muito casos. Apesar de considerada inevitável em alguns casos, a sua incidência poderia (e deveria) ser reduzida através da busca por fármacos mais seguros. A avaliação abrangente de um episódio é um dos elementos primordiais para tornar a exposição subsequente mais segura, com orientações derivadas dessa investigação. Entretanto, representa um desafio estatístico por ser reação rara, randômica e muitas vezes independente de exposições sucessivas dos pacientes a procedimentos de baixo risco. Neste documento são revisados os mecanismos fisiopatológicos, agentes desencadeantes (adultos e crianças), assim como a abordagem diagnóstica durante a crise e após o episódio. Uma avaliação abrangente, a identificação das medicações, antissépticos e outras substâncias usadas em cada região, registros detalhados e nomenclatura padronizada são pontos fundamentais para a obtenção de dados epidemiológicos mais fidedignos sobre a anafilaxia perioperatória.

Perioperative anaphylaxis is an important manifestation in the context of surgery-related adverse events. Although often related to anesthetic induction, it may be caused by other agents administered by other routes. Anaphylaxis may manifest as cardiovascular collapse, airway obstruction and/or respiratory failure with or without skin manifestation, resulting often in death. Although this reaction is considered inevitable in some cases, its incidence could (and should) be reduced by the search for safer drugs. Comprehensive assessment of an allergic reaction is a key element to make subsequent exposure safer, with guidance derived from this investigation. However, surveillance of perioperative anaphylaxis represents a statistical challenge because this is a rare, random reaction and often independent of successive patient exposures to low-risk procedures. This paper reviews pathophysiological mechanisms, triggering agents (adults and children), as well as therapeutic and diagnostic approach during and after an allergic reaction. Comprehensive assessment, identification of medications/antiseptics used in each region and detailed records with standardized terminology are key points for obtaining more reliable epidemiological data on perioperative anaphylaxis.

A role for mast cells and mast cell tryptase in driving neutrophil recruitment in LPS-induced lung inflammation via protease-activated receptor 2 in mice.

OBJECTIVE: This study aims to investigate the role of protease-activated receptor (PAR) 2 and mast cell (MC) tryptase in LPS-induced lung inflammation and neutrophil recruitment in the lungs of C57BL/6 mice. METHODS: C57BL/6 mice were pretreated with the PAR2 antagonist ENMD-1068, compound 48/80 or aprotinin prior to intranasal instillation of MC tryptase or LPS. Blood leukocytes, C-X-C motif chemokine ligand (CXCL) 1 production leukocytes recovered from bronchoalveolar lavage fluid (BALF), and histopathological analysis of the lung were evaluated 4 h later. Furthermore, we performed experiments to determine intracellular calcium signaling in RAW 264.7 cells stimulated with LPS in the presence or absence of a protease inhibitor cocktail or ENMD-1068 and evaluated PAR2 expression in the lungs of LPS-treated mice. RESULTS: Pharmacological blockade of PAR2 or inhibition of proteases reduced neutrophils recovered in BALF and LPS-induced calcium signaling. PAR2 blockade impaired LPS-induced lung inflammation, PAR2 expression in the lung and CXCL1 release in BALF, and increased circulating blood neutrophils. Intranasal instillation of MC tryptase increased the number of neutrophils recovered in BALF, and MC depletion with compound 48/80 impaired LPS-induced neutrophil migration. CONCLUSION: Our study provides, for the first time, evidence of a pivotal role for MCs and MC tryptase in neutrophil migration, lung inflammation and macrophage activation triggered by LPS, by a mechanism dependent on PAR2 activation.

[Anaphylaxis caused by dermal exposure with cow's milk in an adult with food allergy. A case report]. / Anafilaxia por contacto con leche en un adulto con alergia alimentaria. Reporte de caso.

BACKGROUND: Allergy to cow's milk proteins is the most frequent food allergy and its prevalence has increased in the last decade. Although most patients have symptoms after the intake of dairy milk, other routes of sensitization through skin and mucous membranes have been described. CASE REPORT: A 31-year-old male patient who is a professional chef and started with oropharyngeal symptoms after the intake of milk. Since he tolerated other dairy products, he did not suppress them from his diet. However, the clinical picture progressed and cutaneous symptoms were added; finally, anaphylaxis occurred by contact with bread dough that contained butter and milk. The patient was treated in the emergency department, where an increase in serum tryptase was verified. Skin prick tests and serological tests were positive for milk and its fractions. CONCLUSION: Reports of anaphylaxis caused by dermal contact with cow's milk are very scarce and they have been reported only in children. We believe that repeated food handling could favor cutaneous sensitization in adults with a personal history of atopy.

Antecedentes: La alergia a proteínas de leche de vaca es la alergia alimentaria más frecuente y su prevalencia se ha incrementado en la última década. Aunque la mayoría de los pacientes presenta síntomas por ingestión, se ha descrito sensibilización cutánea y de mucosas. Caso clínico: Hombre de 31 años, chef de profesión, en quien se iniciaron síntomas orofaríngeos después de la ingesta de leche. No suprimió de su dieta otros productos lácteos que toleraba en ese momento, sin embargo, los cuadros alérgicos fueron progresando y se añadieron manifestaciones cutáneas; finalmente presentó anafilaxia por contacto con masa de pan que contenía mantequilla y leche. El paciente fue atendido en urgencias, donde se comprobó la elevación de la triptasa sérica. Las pruebas cutáneas y serológicas resultaron positivas para leche y sus derivados. Conclusión: La anafilaxia por contacto con leche es infrecuente y solo se ha informado en niños. Consideramos que la manipulación repetida de alimentos pudiera favorecer la sensibilización cutánea en adultos con historia personal de atopia.

Atualização sobre reações de hipersensibilidade perioperatória: Documento conjunto da Sociedade Brasileira de Anestesiologia e Associação Brasileira de Alergia e Imunologia ­ Parte II: etiologia e diagnóstico / Update on perioperative hypersensitivity reactions: Joint document from the Brazilian Society of Anesthesiology and Brazilian Association of Allergy and Immunology ­ Part II: Etiology and diagnosis

A anafilaxia perioperatória é manifestação importante no contexto de eventos adversos relacionados à cirurgia. Embora frequentemente relacionada à indução anestésica, pode ocorrer por outros agentes administrados por outras vias. A anafilaxia pode se apresentar como colapso cardiovascular, obstrução da via aérea e/ou insuficiência respiratória com ou sem manifestação cutânea, com consequências fatais em muito casos. Apesar de considerada inevitável em alguns casos, a sua incidência poderia (e deveria) ser reduzida através da busca por fármacos mais seguros. A avaliação abrangente de um episódio é um dos elementos primordiais para tornar a exposição subsequente mais segura, com orientações derivadas dessa investigação. Entretanto, representa um desafio estatístico por ser reação rara, randômica e muitas vezes independente de exposições sucessivas dos pacientes a procedimentos de baixo risco. Neste documento são revisados os mecanismos fisiopatológicos, agentes desencadeantes (adultos e crianças), assim como a abordagem diagnóstica durante a crise e após o episódio. Uma avaliação abrangente, a identificação das medicações, antissépticos e outras substâncias usadas em cada região, registros detalhados e nomenclatura padronizada são pontos fundamentais para a obtenção de dados epidemiológicos mais fidedignos sobre a anafilaxia perioperatória.

Perioperative anaphylaxis is an important manifestation in the context of surgery-related adverse events. Although often related to anesthetic induction, it may be caused by other agents administered by other routes. Anaphylaxis may manifest as cardiovascular collapse, airway obstruction and/or respiratory failure with or without skin manifestation, resulting often in death. Although this reaction is considered inevitable in some cases, its incidence could (and should) be reduced by the search for safer drugs. Comprehensive assessment of an allergic reaction is a key element to make subsequent exposure safer, with guidance derived from this investigation. However, surveillance of perioperative anaphylaxis represents a statistical challenge because this is a rare, random reaction and often independent of successive patient exposures to low-risk procedures. This paper reviews pathophysiological mechanisms, triggering agents (adults and children), as well as therapeutic and diagnostic approach during and after an allergic reaction. Comprehensive assessment, identification of medications/antiseptics used in each region and detailed records with standardized terminology are key points for obtaining more reliable epidemiological data on perioperative anaphylaxis.

Análise de células dendríticas, mastócitos e vascularização na doença periodontal biofilme induzida em idosos / Analysis of dendritic cells, mast cells and vasculature in biofilm-induced periodontal disease in the elderly

A microbiota e o sistema imune do idoso apresentam algumas alterações, favorecendo ao aparecimento de infecções e doenças inflamatórias. A doença periodontal é um exemplo, permeando entre fase imediata e tardia, pode ter alterações em sua evolução com o envelhecimento humano. Compreender a doença periodontal e sua relação com o ciclo da vida é importante para a prevenção, tratamento e cura. Este estudo tem como objetivo avaliar a quantidade de mastócitos (triptase), células dendríticas imaturas (CD1a), células dendríticas maduras (CD83) e vasos sanguíneos (CD34) em 154 tecidos periodontais saudáveis e doentes (27 idosos e 127 adultos). Foi utilizada a técnica de imunoistoquímica através da imunomarcação do CD1a, CD83, triptase e CD34, sendo contabilizados em 5 campos de maior número de células positivas, no aumento de 1000x. Para o CD34, ainda foram calculadas a área e o perímetro microvascular para todos os vasos sanguíneos presentes, e dos vasos com presença do endotélio vascular alto. Não houve diferença na imunomarcação das células dendríticas, dos mastócitos e na quantidade de vasos sanguíneos nos tecidos gengivais, entre os casos de gengiva clinicamente saudável, gengivite induzida por biofilme e periodontite estágios II, III e IV, avaliando isoladamente os grupos etários: adultos e idosos. As células dendríticas imaturas são mais numerosas no idoso com o quadro clínico de gengivite e periodontite. Os adultos com gengivite induzida por biofilme possuem maior quantidade de vasos sanguíneos que o grupo idoso. A área microvascular e o perímetro microvascular dos vasos sanguíneos com o endotélio vascular alto apresentaram maiores nos idosos nos casos de gengivite. Este estudo concluiu que nesta amostra não houve diferença na quantidade de células dendríticas imaturas e maduras, mastócitos na doença periodontal dentro dos grupos etário, porém as células dendríticas imaturas estão mais presentes no idoso podendo estar relacionado a algum decréscimo funcional. Em relação aos vasos sanguíneos, há presença de HEVs em adultos e idosos, não havendo diferença entre os diagnósticos. Nos idosos com gengivite há um aumento da área microvascular e perímetro microvascular, necessitando de estudos que justifiquem esta diferença (AU).

The elderly's microbiota and immune system show some changes, favoring the onset of infections and inflammatory diseases. Periodontal disease is an example, permeating between immediate and adaptative stages, it can have changes in its evolution with human aging. Understanding periodontal disease and its relationship with the life cycle is important for prevention, treatment and cure. This study aims to assess the amount of mast cells (tryptase), immature dendritic cells (CD1a), mature dendritic cells (CD83) and blood vessels (CD34) in 154 healthy and sick periodontal tissues (27 elderly and 127 adults). The immunohistochemistry technique was used through the immunostaining of CD1a, CD83, tryptase and CD34, being counted in 5 fields with a greater number of positive cells, in the 1000x increase. For CD34, the microvascular area and perimeter were also calculated for all blood vessels present, and for vessels with the presence of high vascular endothelium. There was no difference in the immunostaining of dendritic cells, mast cells and the amount of blood vessels in the gingival tissues, between cases of clinically healthy gingiva, biofilm-induced gingivitis and stages II, III and IV periodontitis, evaluating the age groups: adults and elderly. Immature dendritic cells are more numerous in the elderly with the clinical picture of gingivitis and periodontitis. Adults with biofilm-induced gingivitis have a greater amount of blood vessels than the elderly group. The microvascular area and the microvascular perimeter of the blood vessels with the high vascular endothelium were larger in the elderly in cases of gingivitis. This study concluded that in this sample there was no difference in the amount of immature and mature dendritic cells, mast cells in periodontal disease within the age groups, however, immature dendritic cells are more present in the elderly and may be related to some functional decrease. Regarding blood vessels, there are HEVs in adults and the elderly, with no difference between diagnoses. In the elderly with gingivitis there is an increase in the microvascular area and microvascular perimeter, requiring studies that justify this difference (AU).

Relationship between mast cells and E-cadherin in odontogenic keratocysts and radicular cysts.

OBJECTIVE: This study aimed to evaluate tryptase and E-cadherin protein expression in odontogenic keratocysts (OKCs) and radicular cysts (RCs) and their relationship with lesion size. MATERIALS AND METHODS: Thirty OKC and 30 RC cases were analyzed by immunohistochemistry. Tryptase expression was quantitatively assessed using the quantification of mast cells, and expression of E-cadherin was semi-quantitatively analyzed estimating the proportion of positive cells: 1 = less than 25% of immunopositive cells; 2 = 26 to 50% of immunopositive cells; 3 = 51 to 75% of immunopositive cells; 4 = more than 75% of immunopositive cells. Data on cystic lesion sizes were obtained from patients' clinical files, based on previous radiographic exams, and the lesions were categorized into three groups: group 1 (< 2 to 2 cm); group 2 (> 2 to 4 cm), and group 3 (> 4 cm). RESULTS: Higher mast cell means were found for RCs, with the predominance of degranulated mast cells in both OKCs and RCs (p = 0.082). Concerning the epithelial component, a higher concentration of degranulated mast cells was detected in RCs (p = 0.000). Regarding connective tissue, degranulated mast cells were more evident in OKCs (p = 0.762). A negative correlation was observed between E-cadherin expression and total number of mast cells (p = 0.011), degranulated mast cells (p = 0.040), and degranulated mast cells in both superficial (p = 0.035) and deep connective tissues (p = 0.009). Concerning lesion size, a negative correlation with total number of mast cells (p = 0.016) and number of degranulated mast cells (p = 0.049) was observed, both in the epithelial components. Herein, the larger the lesion size, the lower the number of degranulated mast cells in the epithelium (r = - 0.271; p = 0.49), suggesting that these cells play a role in the initial cystic expansion phase. CONCLUSION: The higher expression of tryptase in degranulated mast cells was linked to a lower expression of E-cadherin, which may be related to a change in the epithelial permeability in these lesions, contributing to increased cystic content and lesion growth. CLINICAL RELEVANCE: Evidence of the relationship between mast cells and E-cadherin in the growth of odontogenic cysts was studied.

Serum Baseline Tryptase Level as a Marker for the Severity of Anaphylaxis.

BACKGROUND: Anaphylaxis is a severe and potentially fatal allergic disease or hypersensitivity reaction with variable clinical presentation. Biomarkers in anaphylaxis could be useful to improve diagnosis, to allow endotyping of patients, and to predict risk. OBJECTIVE: To investigate the role of serum basal tryptase (sBT) levels in the management of patients with anaphylaxis. METHODS: Patients with at least 1 episode of anaphylaxis were selected among those who attended the Allergy Clinics of the Clinical Hospital of the Ribeirão Preto Medical School, University of São Paulo, Brazil, upon evaluation by allergy/immunology specialists of our medical staff. Demographic and clinical data were obtained using a structured questionnaire. sBT levels were determined using the ImmunoCAP Tryptase immunoassay. RESULTS: 57 patients (56.1% female) with a median age of 35 years (range 7-87 years) participated in the study. sBT levels ranged from 2.57 to 21.19 ng/mL (mean 5.17 ng/mL), with no significant differences in patients with anaphylaxis due to different triggers. Mean levels were 4.93; 5.2; 5.41, and 5.24 ng/mL for patients who had anaphylaxis due to Hymenoptera venom (n = 17), foods (n = 13), drugs (n = 13), and idiopathic disease (n = 14), respectively. Significantly higher sBT levels were observed in patients with severe anaphylaxis (grade IV) than in patients with mild-moderate disease (grades II/III) (mean levels 6.61 vs. 4.71 ng/mL, respectively). CONCLUSION: High sBT levels may help to identify patients at increased risk of more severe anaphylaxis, prompting physicians to initiate immediate therapy to avoid further acute episodes.

[Mast cell activation syndrome. About a clinical case]. / Síndrome de activación mastocitaria. A propósito de un caso clínico.

BACKGROUND: Monoclonal mast cell activation syndrome is included in mast cell activation disorders in which, after a diagnostic process, it is not possible to meet the required criteria for a diagnosis of systemic mastocytosis. CLINICAL CASE: A 73-year-old woman who presented two events of anaphylaxis 15 minutes after the intake of yucca; with a positive skin test, elevated tryptase, and mast cells with abnormal phenotype in the bone marrow biopsy, and without criteria for systemic mastocytosis. CONCLUSION: The diagnosis of monoclonal mast cell activation syndrome requires high clinical suspicion for patients with recurrent anaphylaxis and elevated tryptase, for whom joint management with hematology is essential.

Antecedentes: Entre los desórdenes de activación mastocitaria se incluye el síndrome de activación monoclonal de mastocitos, que no cumple con los criterios requeridos para hacer el diagnóstico de mastocitosis sistémica. Caso clínico: Mujer de 73 años que presentó dos cuadros de anafilaxia 15 minutos después del consumo de yuca, con prueba cutánea positiva, triptasa elevada y mastocitos con fenotipo anormal en la biopsia de médula ósea, sin criterios de mastocitosis sistémica. Conclusiones: El diagnóstico de síndrome de activación monoclonal de mastocitos requiere alta sospecha clínica ante pacientes con anafilaxia recurrente y triptasa elevada, en quienes es indispensable el manejo conjunto con hematología.

Mast cell heterogeneity and anti-inflammatory annexin A1 expression in leprosy skin lesions.

Mast cells (MCs) have important immunoregulatory roles in skin inflammation. Annexin A1 (ANXA1) is an endogenous anti-inflammatory protein that can be expressed by mast cells, neutrophils, eosinophils, monocytes, epithelial and T cells. This study investigated MCs heterogeneity and ANXA1 expression in human dermatoses with special emphasis in leprosy. Sixty one skin biopsies from 2 groups were investigated: 40 newly diagnosed untreated leprosy patients (18 reaction-free, 11 type 1 reaction/T1R, 11 type 2 reaction/T2R); 21 patients with other dermatoses. Tryptase/try+ and chymase/chy + phenotypic markers and toluidine blue stained intact/degranulated MC counts/mm2 were evaluated. Try+/chy+ MCs and ANXA1 were identified by streptavidin-biotin-peroxidase immunostaining and density was reported. In leprosy, degranulated MCs outnumbered intact ones regardless of the leprosy form (from tuberculoid/TT to lepromatous/LL), leprosy reactions (reactional/reaction-free) and type of reaction (T1R/T2R). Compared to other dermatoses, leprosy skin lesions showed lower numbers of degranulated and intact MCs. Try+ MCs outnumbered chy+ in leprosy lesions (reaction-free/reactional, particularly in T2R), but not in other dermatoses. Compared to other dermatoses, ANXA1 expression, which is also expressed in mast cells, was higher in the epidermis of leprosy skin lesions, independently of reactional episode. In leprosy, higher MC degranulation and differential expression of try+/chy+ subsets independent of leprosy type and reaction suggest that the Mycobacterium leprae infection itself dictates the inflammatory MCs activation in skin lesions. Higher expression of ANXA1 in leprosy suggests its potential anti-inflammatory role to maintain homeostasis preventing tissue and nerve damage.

Mast cell-nerve interaction in the colon of Trypanosoma cruzi-infected individuals with chagasic megacolon.

Chagas disease is an infection caused by the parasite Trypanosoma cruzi that affects millions of people worldwide and is endemic in Latin America. Megacolon is the most frequent complication of the digestive chronic form and happens due to lesions of the enteric nervous system. The neuronal lesions seem to initiate in the acute phase and persist during the chronic phase, albeit the mechanisms involved in this process are still debated. Among the cells of the immune system possibly involved in this pathological process is the mast cell (MC) due to its well-known role in the bi-directional communication between the immune and nervous systems. Using ultrastructural analysis, we found an increased number of degranulated MCs in close proximity to nerve fibers in infected patients when compared with uninfected controls. We also immunostained MCs for the two pro-inflammatory molecules tryptase and chymase, the first being also important in neuronal death. The number of MCs immunostained for tryptase or chymase was increased in patients with megacolon, whereas increased tryptase staining was additionally observed in patients without megacolon. Moreover, we detected the expression of the tryptase receptor PAR2 in neurons of the enteric nervous system, which correlated to the tryptase staining results. Altogether, the data presented herein point to the participation of MCs on the denervation process that occurs in the development of T. cruzi-induced megacolon.

Monoclonal Antibodies Hypersensitivity: Prevalence and Management.

The use of monoclonal antibodies (mAbs) has become broader because of their recognized effectiveness in the treatment of autoimmune, neoplastic, and inflammatory diseases. Consequently, hypersensitivity reactions (HSR) secondary to mAbs are being reported more often, and each mAb-related HSR presents specific features. This article discusses the main biological agents and associated HSR, the clinical presentation of such reactions, and the role of tryptase and skin testing in the diagnosis. Rapid drug desensitization procedures to mAbs enable selected allergic patients to receive full therapeutic doses in a safe manner and are also discussed.

Effect of tryptase inhibition on joint inflammation: a pharmacological and lentivirus-mediated gene transfer study.

BACKGROUND: Increasing evidences indicate that an unbalance between tryptases and their endogenous inhibitors, leading to an increased proteolytic activity, is implicated in the pathophysiology of rheumatoid arthritis. The aim of the present study was to evaluate the impact of tryptase inhibition on experimental arthritis. METHODS: Analysis of gene expression and regulation in the mouse knee joint was performed by RT-qPCR and in situ hybridization. Arthritis was induced in male C57BL/6 mice with mBSA/IL-1ß. Tryptase was inhibited by two approaches: a lentivirus-mediated heterologous expression of the human endogenous tryptase inhibitor, sperm-associated antigen 11B isoform C (hSPAG11B/C), or a chronic treatment with the synthetic tryptase inhibitor APC366. Several inflammatory parameters were evaluated, such as oedema formation, histopathology, production of IL-1ß, -6, -17A and CXCL1/KC, myeloperoxidase and tryptase-like activities. RESULTS: Spag11c was constitutively expressed in chondrocytes and cells from the synovial membrane in mice, but its expression did not change 7 days after the induction of arthritis, while tryptase expression and activity were upregulated. The intra-articular transduction of animals with the lentivirus phSPAG11B/C or the treatment with APC366 inhibited the increase of tryptase-like activity, the late phase of oedema formation, the production of IL-6 and CXCL1/KC. In contrast, neutrophil infiltration, degeneration of hyaline cartilage and erosion of subchondral bone were not affected. CONCLUSIONS: Tryptase inhibition was effective in inhibiting some inflammatory parameters associated to mBSA/IL-1ß-induced arthritis, notably late phase oedema formation and IL-6 production, but not neutrophil infiltration and joint degeneration. These results suggest that the therapeutic application of tryptase inhibitors to rheumatoid arthritis would be restrained to palliative care, but not as disease-modifying drugs. Finally, this study highlighted lentivirus-based gene delivery as an instrumental tool to study the relevance of target genes in synovial joint physiology and disease.

Analysis of tryptase-positive mast cells and immunoexpression of MMP-9 and MMP-13 in periapical lesions.

AIM: To evaluate the immunoexpression of tryptase, MMP-9 and MMP-13 in periapical lesions, correlating them with the type of lesion, intensity of the inflammatory infiltrate and thickness of the epithelial lining. METHODOLOGY: Twenty periapical granulomas (PGs), twenty radicular cysts (RCs) and twenty residual radicular cysts (RRCs) were submitted to immunohistochemical analysis using antitryptase, anti-MMP-9 and anti-MMP-13 antibodies. Immunoexpression of MMP-9 and MMP-13 was quantitatively evaluated both in the connective tissue of all lesions and in the epithelial lining of RCs and RRCs. Tryptase-positive mast cells were counted only in the connective tissue. The data were analysed using Kruskal-Wallis and Fisher's exact tests, as well as Spearman's correlation test (P < 0.05). RESULTS: In comparison with RCs and RRCs, PGs exhibited higher immunoexpression of tryptase, MMP-9 and MMP-13 (P = 0.002, P = < 0.001 and P < 0.001, respectively). In comparison with lesions with inflammatory infiltrates grades I and II, lesions with inflammatory infiltrate grade III had higher median percentages of MMP-13-positive cells (P = 0.003) and a tendency for higher expression of MMP-9 (P = 0.059). No significant difference was observed between the expression of the studied markers and epithelial thickness (P > 0.05). There were positive correlations between the number of tryptase-positive mast cells and the immunoexpression of MMP-9, as well as between the immunoexpression of MMP-9 and MMP-13. CONCLUSION: A larger number of tryptase-positive mast cells and greater enzymatic activity of MMP-9 and MMP-13 were found in PGs compared to RCs and RRCs. These findings are a characteristic of the dynamics of periapical diseases.