Comparable profiles of the immunoglobulin heavy chain complementarity determining region (CDR)-3 in CD5+ and CD5- human cord blood B lymphocytes.
It has been suggested that CD5+ B cells are closely related to the pathogenesis of autoimmune disease or chronic lymphocytic leukaemia, whereas the origin and physiological role of CD5+ B cells remain controversial. To study the molecular differences between CD5+ and CD5- B cells in terms of immunoglobulin gene structure, we sorted both subsets from new-born cord blood and analysed the complementarity determining region (CDR)-3 profiles of the immunoglobulin heavy chain (IgH) gene. The CDR-3 sequences from both CD5+ and CD5- B cells represented the same incidence and length of N-region, and the same usage of D and JH segments. When translated into amino acids, 24 of 32 clones (75%) and 25 of 37 clones (65.8%) from their respective subset were productive, and the composition of the deduced amino acids were similar between both subsets. These data suggest that CD5+ B cells are not a distinct lineage presenting a biased immunoglobulin repertoire in B cells.
Kiyoi
H
H
Department of Medicine, Branch Hospital, Nagoya University School of Medicine, Japan.
Naito
K
K
Ohno
R
R
Naoe
T
T
D000595:Amino Acid Sequence; D015703:Antigens, CD / Q000235:genetics*; D001402:B-Lymphocytes / Q000276:immunology*; D001483:Base Sequence; D018956:CD5 Antigens; D005312:Fetal Blood / Q000276:immunology*; D006801:Humans; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D008969:Molecular Sequence Data
D015703:Antigens, CD; D018956:CD5 Antigens; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region