1. |
- Thurner, Lorenz, et al.
(author)
-
Lymphocyte predominant cells detect Moraxella catarrhalis-derived antigens in nodular lymphocyte-predominant Hodgkin lymphoma
- 2020
-
In: Nature Communications. - : Nature Publishing Group. - 2041-1723. ; 11:1
-
Journal article (peer-reviewed)abstract
- Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare lymphoma of B-cell origin with frequent expression of functional B-cell receptors (BCRs). Here we report that expression cloning followed by antigen screening identifies DNA-directed RNA polymerase beta' (RpoC) from Moraxella catarrhalis as frequent antigen of BCRs of IgD(+) LP cells. Patients show predominance of HLA-DRB1*04/07 and the IgVH genes encode extraordinarily long CDR3s. High-titer, light-chain-restricted anti-RpoC IgG1/kappa -type serum-antibodies are additionally found in these patients. RpoC and MID/hag, a superantigen co-expressed by Moraxella catarrhalis that is known to activate IgD(+) B cells by binding to the Fc domain of IgD, have additive activation effects on the BCR, the NF-kappa B pathway and the proliferation of IgD(+) DEV cells expressing RpoC-specific BCRs. This suggests an additive antigenic and superantigenic stimulation of B cells with RpoC-specific IgD(+) BCRs under conditions of a permissive MHC-II haplotype as a model of NLPHL lymphomagenesis, implying future treatment strategies. Nodular lymphocyte-predominant Hodgkin lymphoma with IgD+ lymphocyte-predominant (LP) cells is a rare clinical distinct lymphoma subset of B-cell origin. Here the authors show that antigens expressed by Moraxella catarrhalis are recognized by B cell receptors of IgD+ LP cells, suggesting the contribution of chronic antigen stimulation to lymphomagenesis.
|
|
2. |
- Giefing, Maciej, et al.
(author)
-
Loss of function mutations of BCOR in classical Hodgkin lymphoma
- 2022
-
In: Leukemia and Lymphoma. - : Informa UK Limited. - 1042-8194 .- 1029-2403. ; 63:5, s. 1080-1090
-
Journal article (peer-reviewed)abstract
- BCOR is a component of a variant Polycomb repressive complex 1 (PRC1.1). PRC1 and PRC2 complexes together constitute a major gene regulatory system critical for appropriate cellular differentiation. The gene is upregulated in germinal center (GC) B cells and mutated in a number of hematologic malignancies. We report BCOR inactivating alterations in 4/7 classic Hodgkin lymphoma (cHL) cell lines, subclonal somatic mutations in Hodgkin and Reed-Sternberg (HRS) cells of 4/10 cHL cases, and deletions in HRS cells of 7/17 primary cHL cases. In mice, conditional loss of Bcor driven by AID-Cre in GC B cells resulted in gene expression changes of 46 genes (>2-fold) including upregulated Lef1 that encodes a transcription factor responsible for establishing T-cell identity and Il9r (interleukin-9 receptor), an important member of the cytokine network in cHL. Our findings suggest a role for BCOR loss in cHL pathogenesis and GC-B cell homeostasis.
|
|