RESUMO
Smooth muscle myosin heavy chain (SMMHC) is a major structural component of the contractile apparatus in smooth muscle cells. Even though it is considered a relatively specific marker for terminal smooth muscle cell differentiation, expression in other cell types such as follicular dendritic cells (FDCs) has rarely been reported. To determine whether SMMHC represents an effective FDC marker in lymphoid tissues, we compared the immunohistochemical results for SMMHC with those of the traditional FDC markers podoplanin (D2-40) and CD21. Paraffin sections of 44 lymphoid tissues were analyzed, including 31 cases of follicular hyperplasia, 6 cases of follicular lymphoma, 2 cases of peripheral T-cell lymphoma, 3 cases of diffuse large B-cell lymphoma arising in follicular lymphoma, 1 case of nodular sclerosis classical Hodgkin lymphoma, and 1 case of small lymphocytic lymphoma. There was no statistically significant difference between the number of SMMHC-positive and D2-40-positive or CD21 lymph nodes (P>0.05). The extent and intensity of SMMHC-positive FDCs were similar to those of D2-40-positive FDCs (P=0.127 and 0.733, respectively), but significantly lower compared with those of CD21 cells (P=0.009 and 0.00002, respectively). However, in contrast to CD21 which was also positive in some germinal center B cells, SMMHC expression was restricted to FDCs. Our results indicate that SMMHC is an excellent marker for FDCs and can be particularly helpful in demonstrating the underlying architecture in lymphoid processes.
Assuntos
Linfócitos B/metabolismo , Biomarcadores Tumorais/metabolismo , Células Dendríticas Foliculares/metabolismo , Linfonodos/metabolismo , Linfoma Folicular/metabolismo , Miócitos de Músculo Liso/fisiologia , Cadeias Pesadas de Miosina/metabolismo , Diferenciação Celular , Células Dendríticas Foliculares/patologia , Humanos , Imuno-Histoquímica , Linfonodos/patologia , Linfoma Folicular/diagnóstico , Linfoma Folicular/patologia , Glicoproteínas de Membrana/metabolismo , Receptores de Complemento 3d/metabolismoRESUMO
BACKGROUND: B cell lymphomas' (BCL) current diagnosis is usually based on a combination of morphology, immunophenotype, recurrent cytogenetic aberration and clinical features. However, even with these diagnostic tools, a definitive diagnosis can be difficult to achieve. Therefore, the aim of this study was to assess the profile of CD39, CD43, CD81, and CD95 expressions in diffuse large B cell lymphoma (DLBCL), follicular lymphoma (FL), and Burkitt lymphoma (BL) cases. METHODS: To address this issue, we investigated the expression of CD39, CD43, CD81, and CD95 by eight-color flow cytometry in retrospective cases from 2014 to 2016. RESULTS: The study included 27 adult patients diagnosed with DLBCL, FL, and BL during the study period. Four patients were diagnosed with germinal center B cell-like DLBCL (GCB DLBCL), seven with non-GCB DLBCL, nine with FL, and seven with BL. CD39 seems to be especially relevant to differentiate non-GCB DLBCL from BL and from FL. BL showed stronger expression of CD43 when compared to FL and GCB DLBCL. Moreover, CD43 may help to distinguish non-GCB DLBCL from GCB DLBCL. CD81 expression was much stronger in BL when compared to the other three groups of patients. Lastly, CD95 may also help to distinguish BL from the other subtypes, as BL cells expressed this antigen at low levels. CONCLUSIONS: In combination, CD39, CD43, CD81, and CD95 expressions appear to be helpful to distinguish CD10+ BCL, particularly BL. Phenotypic distinction between FL and GCB DLBCL remains challenging and requires further studies. © 2017 International Clinical Cytometry Society.
Assuntos
Apirase/metabolismo , Leucossialina/metabolismo , Linfoma Difuso de Grandes Células B/metabolismo , Tetraspanina 28/metabolismo , Receptor fas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos B/metabolismo , Biomarcadores Tumorais/metabolismo , Linfoma de Burkitt/metabolismo , Feminino , Citometria de Fluxo/métodos , Centro Germinativo/metabolismo , Humanos , Imunofenotipagem/métodos , Linfoma Folicular/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
OBJECTIVES: CD279 expression is used to help identify angioimmunoblastic T-cell lymphoma (AITL) or other T-cell lymphomas of T-follicular helper (TFH) cell origin; however, its utility in assessing lymphoid infiltrates in the bone marrow (BM) is not well established. METHODS: Immunohistochemistry for CD279 was performed on normal staging BM and in BM with benign lymphoid aggregates (LAs), AITLs, and other T-cell lymphomas. RESULTS: Seven of 10 staging BMs demonstrated scattered, usually weakly CD279+ cells. Thirty-four of 38 BMs had scattered weakly/variably intense CD279+ cells within LAs, but only four contained 11% to 25% CD279+ cells. Three of four AITLs were strongly CD279+, but one contained only around 10% CD279+ cells. Eleven of the other 38 T-cell lymphomas were CD279+, including five possible AITLs; four peripheral T-cell lymphomas, not otherwise specified; and two T-cell large granular lymphocytic leukemias. CONCLUSIONS: Although useful in assessing selected BM lymphoid infiltrates, CD279 expression may be limited in AITLs, is not specific for TFH lymphomas, and can be seen in benign lymphoid infiltrates, although without extensive strong positivity.
Assuntos
Medula Óssea/metabolismo , Linfonodos/metabolismo , Linfoma Folicular/diagnóstico , Linfoma de Células T/diagnóstico , Receptor de Morte Celular Programada 1/metabolismo , Medula Óssea/patologia , Diagnóstico Diferencial , Humanos , Imuno-Histoquímica , Linfonodos/patologia , Linfoma Folicular/metabolismo , Linfoma Folicular/patologia , Linfoma de Células T/metabolismoRESUMO
The aims of this study were: 1) to identify the type of bcl-2 rearrangement in a Brazilian group of FL patients and 2) to correlate it to clinical features, International Prognostic Index (IPI), histological subtype, response to treatment and clinical outcome. We reviewed the diagnosis of 48 patients with FL and investigated the type of bcl-2 gene rearrangement using DNA from paraffin-embedded tumor samples obtained at the time of diagnosis. In 30 cases, we also obtained consecutive peripheral blood samples to search for the presence of bcl-2/IgH rearrangement. Molecular analysis identified 41 (86%) patients with MBR and 5 (10%) patients with mcr rearrangement. In this study, the type of rearrangement was not associated with clinical characteristics or IPI. In addition, the type of rearrangement did not have an impact on response to initial treatment or on clinical outcome. However, we found an association between the type of rearrangement and the histological subtype of FL, i.e., none of mcr-positive patients presented histological grade I (p = 0.043). In this study, we could not demonstrate a relationship between the type of bcl-2 rearrangement and the response to treatment or outcome. However, we found a relationship between the type of rearrangement and FL histological subtype, information not previously reported.