The B cell receptor immunoglobulin (Ig) gene repertoires of marginal zone (MZ) lymphoproliferations were analyzed in order to obtain insight into their ontogenetic relationships. Our cohort included cases with MZ lymphomas (n = 488), i.e. splenic (SMZL), nodal (NMZL) and extranodal (ENMZL), as well as provisional entities (n = 76), according to the WHO classification. The most striking Ig gene repertoire skewing was observed in SMZL. However, restrictions were also identified in all other MZ lymphomas studied, particularly ENMZL, with significantly different Ig gene distributions depending on the primary site of involvement. Cross-entity comparisons of the MZ Ig sequence dataset with a large dataset of Ig sequences (MZ-related or not; n = 65 837) revealed four major clusters of cases sharing homologous ('public') heavy variable complementarity-determining region 3. These clusters included rearrangements from SMZL, ENMZL (gastric, salivary gland, ocular adnexa), chronic lymphocytic leukemia, but also rheumatoid factors and non-malignant splenic MZ cells. In conclusion, different MZ lymphomas display biased immunogenetic signatures indicating distinct antigen exposure histories. The existence of rare public stereotypes raises the intriguing possibility that common, pathogen-triggered, immune-mediated mechanisms may result in diverse B lymphoproliferations due to targeting versatile progenitor B cells and/or operating in particular microenvironments. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

• Klíčová slova
• antigen, immunoglobulin gene, marginal zone lymphoma, ontogeny,
• MeSH
• genová přestavba B-lymfocytů genetika   MeSH
• geny pro imunoglobuliny genetika   MeSH
• geny pro těžké řetězce imunoglobulinů genetika   MeSH
• hypervariabilní oblasti genetika   MeSH
• lidé MeSH
• lymfom z B-buněk marginální zóny genetika   MeSH
• mutace genetika   MeSH
• nádorové mikroprostředí MeSH
• receptory antigenů B-buněk genetika   MeSH
• variabilní oblast imunoglobulinu genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• hypervariabilní oblasti MeSH
• receptory antigenů B-buněk MeSH
• variabilní oblast imunoglobulinu MeSH

PURPOSE: Prompted by the extensive biases in the immunoglobulin (IG) gene repertoire of splenic marginal-zone lymphoma (SMZL), supporting antigen selection in SMZL ontogeny, we sought to investigate whether antigen involvement is also relevant post-transformation. EXPERIMENTAL DESIGN: We conducted a large-scale subcloning study of the IG rearrangements of 40 SMZL cases aimed at assessing intraclonal diversification (ID) due to ongoing somatic hypermutation (SHM). RESULTS: ID was identified in 17 of 21 (81%) rearrangements using the immunoglobulin heavy variable (IGHV)1-2*04 gene versus 8 of 19 (40%) rearrangements utilizing other IGHV genes (P= 0.001). ID was also evident in most analyzed IG light chain gene rearrangements, albeit was more limited compared with IG heavy chains. Identical sequence changes were shared by subclones from different patients utilizing the IGHV1-2*04 gene, confirming restricted ongoing SHM profiles. Non-IGHV1-2*04 cases displayed both a lower number of ongoing SHMs and a lack of shared mutations (per group of cases utilizing the same IGHV gene). CONCLUSIONS: These findings support ongoing antigen involvement in a sizable portion of SMZL and further argue that IGHV1-2*04 SMZL may represent a distinct molecular subtype of the disease.

• MeSH
• alely * MeSH
• aminokyselinové motivy MeSH
• antigeny imunologie   MeSH
• biologické modely MeSH
• hypervariabilní oblasti chemie   genetika   MeSH
• lidé MeSH
• lymfom z B-buněk marginální zóny genetika   imunologie   patologie   MeSH
• mutace MeSH
• nádory sleziny genetika   imunologie   patologie   MeSH
• přestavba genů pro těžké řetězce B-lymfocytů MeSH
• receptory antigenů B-buněk genetika   MeSH
• sekvence aminokyselin MeSH
• stanovení celkové genové exprese MeSH
• substituce aminokyselin MeSH
• těžké řetězce imunoglobulinů chemie   genetika   MeSH
• transkriptom MeSH
• variabilní oblast imunoglobulinu chemie   genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny MeSH
• hypervariabilní oblasti MeSH
• receptory antigenů B-buněk MeSH
• těžké řetězce imunoglobulinů MeSH
• variabilní oblast imunoglobulinu MeSH