Partial plasma cell differentiation as a mechanism of lost major histocompatibility complex class II expression in diffuse large B-cell lymphoma

Abstract

Loss of major histocompatibility complex class II (MHC II)

Lack and/or aberrant localization of major histocompatibility class II (MHCII) protein in plasmablastic lymphoma

“…In addition, the HLA-DR staining pattern was qualitatively characterized as cell membrane ( Figure 1C) or aberrant cytoplasmic ( Figure 1D) as described previously, 8 or as negative. PBL cases with less than 10% of cells showing HLA-DR expression (cell membrane and aberrant cytoplasmic) were grouped together with the negative cases ("Low/Zero HLA-DR").…”

Combined loss of HLA I and HLA II expression is more common in the non‐GCB type of diffuse large B cell lymphoma

“…4 A high expression of FoxP1 with a low expression of HLA class II expression was observed in normal pre-plasma cells and non-GCB-type DLBCL maturing to plasmablasts. 5 This is in line with data from the group of Rimsza et al, suggesting that loss of HLA class II is seen in DLBCL cases maturing into plasmablastic lymphoma. 2,6 We studied the correlation between FoxP1 expression and HLA class II expression in 61 DLBCL cases (Figures S1 and S3).…”

A phase II study of belinostat (PXD101) in relapsed and refractory aggressive B-cell lymphomas: SWOG S0520

“…In our prior study punctate staining cases were grouped together with those with complete lack of staining and together correlated with inferior outcome [4, 30]. A similar aberrant MHCII expression pattern was also documented in Hodgkin lymphoma, which when grouped with true MHC-negative cases correlated with reduced survival [57].…”

“…Immunohistochemistry (IHC) [4, 30], photo microscopy [31], quantitative nuclease protection (qNPA) assays [32], CIITA expression by quantitative RT-PCR [33] and in vitro correlates [34] were all performed as previously described with additional details and modifications available in the supplemental methods, found on Leukemia Lymphoma Web site.…”