Presencia del marcador lmp-1 del virus epstein-barr en linfomas de caninos / Presence of lmp-1 protein of epstein-barr virus in lymphomas of canine origin

RESUMEN El virus Epstein-Barr (EBV) es un virus de alta prevalencia en humanos que se asocia con tumores de la línea linfoide B. En caninos se dispone de pocos reportes sobre la presencia del EBV y su rol en esta especie. El objetivo del presente estudio fue determinar la presencia de la proteína latente de membrana del EBV (LMP-1) en tejidos obtenidos de 20 linfomas de caninos cuyo diagnóstico se había realizado durante un periodo de 10 años, entre 2004 y 2014. Los linfomas se reclasificaron mediante las nuevas clasificaciones histopatológicas para linfomas y se sometieron a inmunohistoquímica (IHQ) con los anticuerpos anti-CD79a, anti-CD3, anticuerpos específicos para linfocitos B y T, además de un anti-LMP-1 como marcador de la presencia del EBV. Se encontró que el linfoma más común fue el linfoma nodal de zona T con un 75% de los casos. Al realizar la inmunomarcación se encontraron 18 casos positivos a CD3, 2 casos positivos a CD79a y 6 casos positivos a LMP-1, lo que representa el 30% de positividad del EBV en linfomas. El análisis Ji cuadrado demostró significancia estadística entre la presencia del virus y la presencia del linfoma lo que sugiere, no solamente que el virus está circulando en la población canina, sino que además puede tener relación con la ocurrencia de esta neoplasia. Con relación a las variables demográficas, sólo en la raza Golden Retriever se demostró relación con la presencia del linfoma, pero no con la presencia del virus.

ABSTRACT Epstein Barr virus (EBV) is a human high prevalent virus associated with lymphoid B cells tumors development. In canines, few reports have been published regarding the presence of the virus in dogs but its role in this species remains unclear. The aim of this study was to determine the presence of LMP-1 protein of EBV in 20 canine lymphomas tissues which were previously diagnosed in a period of time between 2004 -2014. Lymphomas were reclassified in accordance with the new histopathological classifications for lymphomas and were stained by IHQ with anti-CD79a, anti-CD3 and anti-LMP-1; in addition, specific antibodies for B lymphocytes, T lymphocytes and EBV biomarker, respectively. It was found that the most common lymphoma was T-zone lymphoma in 75% of the cases of the study. The distribution of the cases regarding the immunostaining was: 18 positive cases with anti-CD3, 2 positive cases with anti-CD79a and 6 positive cases with anti- LMP-1. Positive cases of LMP-1 as a biomarker of the presence of EBV corresponded to the 30% of the cases of the study. Chi-square test showed statistical significance between the presence of the virus and the presence of lymphomas, which suggests not only that the virus is circulating in the canine population but also that could have implications in the development of the disease. Regarding demographic parameters, only the Golden Retriever breed showed a relationship with the presence of lymphoma, but not with the presence of the virus.

Histomorphological and immunohistochemical characterization of 172 cutaneous round cell tumours in dogs / Caracterização histomorfológica e imuno-histoquímica de 172 neoplasias cutâneas de células redondas em cães

This paper describes the use of a panel of antibodies (CD117, CD3, CD79a, CD45, cytokeratin, vimentin and E-cadherin) on formalin-fixed, paraffin-embedded sections of canine cutaneous round cell tumours. Neoplastic tumours were diagnosed by histology and histochemical stains and included 107 mast cell tumours, 31 cutaneous histiocytomas, two localized histiocytic sarcomas, 21 cutaneous lymphomas, three plasma cell tumours, one transmissible venereal tumour and seven unclassified round cell tumours. The histologic diagnosis was modified in 39.5% of the total 172 neoplasms. The staining for CD45 and Ecadherin were variable, and therefore, the final diagnoses of cutaneous histiocytoma and localized histiocytic sarcoma were made based on histology in association with negative results for CD3, CD79a, CD117 and cytokeratin. The cellular origin of unclassified round cell tumours was defined in all cases. Cutaneous B-cell lymphoma and plasma cell tumours were CD79a-positive and could be distinguished from each other by the morphological characteristics. Mast cell tumours and T cell lymphoma were CD117 and CD3 positive, respectively. The positive staining for vimentin and the negative staining for CD3, CD79a, CD117 and cytokeratin favoured the diagnosis of transmissible venereal tumours. Thus, the final diagnosis of cutaneous round cell tumours should be based on the interpretation of immunohistochemical results together with the cellular morphology observed by histology. Therefore, more studies to optimize the specific markers in formalin-fixed, paraffinembedded tissues (especially for histiocytes) are required for definitive diagnosis of round cell tumours in dogs.

Este trabalho descreve o uso de um painel de anticorpos (CD117, CD3, CD79a, CD45, citoqueratina, vimentina e e-caderina em tecidos formalizados e parafinizados para o diagnóstico de neoplasias de células redondas em cães. Os tumores foram diagnosticados usando-se a histopatologia e a marcação imuno-histoquímica. Foram incluídos 107 mastocitomas, 31 histiocitomas cutâneos, 2 sarcomas histiocíticos localizados, 21 linfomas cutâneos, 3 plasmocitomas, 1 tumor venéreo transmissível e 7 tumores de células redondas não classificados. O diagnóstico histológico foi modificado em 39,5% do total de 172 neoplasias. A marcação do anticorpo CD45 e E-caderina foi variável e, nesse sentido, o diagnóstico final de histiocitoma cutâneo e sarcoma histiocítico localizado foi baseado na histologia em associação com os resultados negativos para CD3, CD79a, CD117 e citoqueratina. A origem celular dos tumores de células redondas não classificados foi definida em todos os casos. Linfoma cutâneo de célula B e plasmocitoma foram positivos para CD79a e foram distinguidos entre si pelas características morfológicas. Marcação positiva para vimentina e negativa para CD3, CD79a, CD117 e citoqueratina favoreceram o diagnóstico dos tumores venereos transmissíveis. Assim, o diagnóstico final dos tumores de células redondas foram baseados na interpretação dos resultados da imuno-histoquímica em conjunto com a avaliação das características morfológicas observadas na histologia. Finalmente, mais estudos em relação à padronização de marcadores específicos para tecidos parafinizados (especialmente para histiócitos) são necessários para o diagnóstico definitivo das neoplasias de células redondas em cães.

Caracterização imunofenotípica e avaliação quantitativa do infiltrado linfocítário junto às áreas de displasia epitelial da próstata de cães adultos sexualmente intactos / Immunophenotipic characterization and quantitative evaluation of lymphocitary infiltrate in areas with prostatic epithelial dysplasia of intact and adult dogs

O estudo da próstata canina tem se tornado comum em razão da grande incidência de doenças prostáticas nessa espécie e das similaridades com as alterações apresentadas pela glândula prostática humana. Frente à alta frequência de displasias epiteliais acompanhadas de infiltrado linfocitário intersticial e atrofia acinar na espécie canina, o presente estudo teve como objetivos a caracterização imunofenotípica e a avaliação quantitativa desse infiltrado, utilizando marcadores para identificação de linfócitos T (anti-CD3) e B (anti-CD79a). Foram catalogadas 42 lesões displásicas classificadas em discreta (48 por cento), moderada (38 por cento) e acentuada (14 por cento). O infiltrado linfocitário intersticial periacinar junto às áreas de epitélio prostático displásico constituiu-se predominantemente por linfócitos T (66 por cento) e houve interação entre o grau histológico da displasia e o marcador imunoistoquímico, com oscilação na quantidade de células T e B intersticiais em função do grau da displasia epitelial.

Canine prostatic studies have been common due to high incidence of prostatic diseases in these animals and similarities with alterations in human prostatic gland. Due the high frequency of dysplasia associated with interstitial lymphocitary infiltrate and acinar atrophy in canine prostate, the aims in this study were the immunophenotypic characterization and the quantitative evaluation of the same infiltrated using anti-CD3 and anti-CD79a to T and B lymphocytes, respectively. Forty two epithelial dysplasic lesions were graduated in discrete (48 percent), moderate (38 percent) and accentuated (14 percent). Lymphocitary periacinar infiltrate in dysplasic areas was T type and interaction between dysplasia grade and marker was observed, with oscillation of T and B cells in according with epithelial dysplasia grade.

Prognostic Effect of cytoplasmic CD79a Expression in Acute Myeloid Leukemia with t(8;21) / 대한진단검사의학회지

BACKGROUND: Although cytoplasmic CD79a (cytCD79a) is a highly lineage-specific marker of B lymphoid cells and plays an important role in the diagnosis of acute leukemia, its clinical significance is not fully understood. We aimed to investigate the relationship between cytCD79a positivity and survival probability, and to evaluate the prognostic value of cytCD79a expression in AML with t(8;21) (q22;q22). METHODS: A total of 68 cases of AML with t(8;21)(q22;q22) were diagnosed based on conventional morphology, cytochemistry, flow cytometrty, and cytogenetic and molecular genetic analysis. Immunohistochemistry of cytCD79a was performed retrospectively. Laboratory and clinical findings were reviewed. RESULTS: Five patients among 68 AML with t(8;21)(q22;q22) revealed cytCD79a positive reaction; scores for myeloid lineage/B-lymphoid lineage were 5/3-3.5. Among the five cytCD79a positive patients, only one patient was a child. Three patients were with refractory AML or relapsed, and two patients died within 10 months. Median survival time of cytCD79a positive group was shorter (8.0 months) than that (61.3 months) of cytCD79a negative group. The survival probability of the cytCD79a expression group was significantly lower than classical AML with t(8;21)(q22;q22) (P=0.0001). CONCLUSIONS: These findings emphasize the necessity of investigating cytCD79a, especially in AML with t(8;21)(q22;q22), for a different clinical prognostic value.