Open AccessRepertoire of CDS + and CD5 − cord blood B cells: specificity and expression of V H I and V H III associated idiotopes
Author(s) -
MACKENZIE L. E.,
MAGEED R. A.,
YOUINOU P. Y.,
YUKSEL B.,
JEFFERIS R.,
LYDYARD P. M.
Publication year - 1992
Publication title -
clinical & experimental immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.329
H-Index - 135
eISSN - 1365-2249
pISSN - 0009-9104
DOI - 10.1111/j.1365-2249.1992.tb03047.x
Subject(s) - idiotopes , cd5 , cord blood , antibody , biology , microbiology and biotechnology , immunoglobulin m , b cell , immunology , idiotype , virology , monoclonal antibody , immunoglobulin g
SUMMARY Epstein‐Barr (EBV)‐immorlalized B cell clones were established from CD5 + and CD5 cord blood B cells separated by flow cytometry. We have previously shown that lgM from many of the clones was polyreacti ve, exhibiting reactivity with a number of autoantigens. In this study, IgM produced by the clones was analysed by MoAb for the expression of cross‐reactive idiotypes (CRI) associated with rheumatoid factor paraproteins and from defined V H and V k subgroups of immunoglobulin heavy and light chains. IgM produced by clones established from CD5 + and CDS B cells expressed the V H I associated idiotope G8. Furthermore, IgM produced by both sets of clones exhibited a similar frequency of V H III heavy chain subgroup expression, as determined by reactivity with staphylo‐coccal protein A (SpA) and V H III‐associated CRI expression (B6 and/or DI2). In contrast, expression of the V, III‐associated 17.109 CRI was significantly higher in IgM antibodies produced by clones established from CD5 + compared with the CD5 – clones(32 versus 5%: P < 0·05). Analysis of the V H and V L subgroup expression by IgM produced by the CD5’ and CD5 cord blood clones, and their autoantigen reactivity profile did not reveal restriction or selection within CD5 + and CD5 – populations. However, our data suggest that differences may exist in the expression of certain germline genes between CD5 + and CD5 – cord blood B cells and might indicate an expansion of CD5 + B cells within the fetal environment.