Premium
Analysis of Ig κ Light Chain Gene Variable Regions Expressed in the Rheumatoid Synovial B Cells
Author(s) -
Pyon H. S.,
HaLee Y. M.,
Song G. G.,
Sohn J.
Publication year - 2001
Publication title -
scandinavian journal of immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.934
H-Index - 88
eISSN - 1365-3083
pISSN - 0300-9475
DOI - 10.1046/j.1365-3083.2001.053005503.x
Subject(s) - somatic hypermutation , complementarity determining region , immunoglobulin light chain , germline mutation , kappa , biology , microbiology and biotechnology , gene , mutation rate , mutation , germline , antibody , complementary dna , affinity maturation , genetics , b cell , linguistics , philosophy
Sequence analysis of antibody variable (V) regions can provide an insight regarding whether B cells have gone through an antigen‐driven process of affinity maturation. In this study, we analyzed 16 V‐regions of immunoglobulin (Ig) κ light chain genes obtained from a cDNA library of a rheumatoid arthritis (RA) synovial tissue. A salient feature of our results is the high frequency utilization of germline VκI family genes, especially the O2/O12 gene (38%). All κ V‐regions showed extensive somatic hypermutation with 5.4% of an average mutation rate. Replacement to silent mutation (R/S) ratio in the complementarity determining region (CDR) was > 2.9 in 12 out of 16 clones, indicating that the majority of the RA synovial B cells had undergone affinity maturation. However, the four other clones showed R/S ratios of < 2.9 in the CDR despite a high mutation rate. In contrast to the previous reports, long CDR3 was not a characteristic feature of these clones. In summary, these data show the high frequency utilization of the germline O2/O12 gene and a high rate of mutation with an evidence of antigen selection in most of the Ig κ genes expressed in the RA synovium.