Ws. Perera et al., V(D)J germline gene repertoire analysis of monoclonal D antibodies and theimplications for D epitope specificity, TRANSFUSION, 40(7), 2000, pp. 846-855
BACKGROUND: The D antigen is a highly immunogenic human RBC antigen. Alloim
munization against the D antigen produces high-affinity antibodies that cau
se hemolytic transfusion reactions and HDN.
STUDY DESIGN AND METHODS: Cloning and subsequent sequence analysis of 11 ne
w samples of monoclonal anti-D was performed in an attempt to identify V(D)
J germline gene usage. Sequences were compared and analyzed with 37 previou
sly published samples of anti-D for identification of V-H acid V-L pairings
, canonical structures, and conformation of restricted germline gene usage.
RESULTS: The V-H and V-L pairings used by the new D MoAbs resulted in seven
canonical combinations, three of which had not been described previously.
Preferential usage of gene segments from the VH3 and VH4 families and of D3
, D6, JH6, and DPK9 germline gene segments was also determined. Three sampl
es of anti-D from different donors were found to use similar V-H and V-kapp
a germline genes, despite the fact that two of the antibodies recognized ep
D6/7 and the third recognized epD1. From the cumulative analysis of the ant
i-D IgG, 24 V-H and V-L gene pairings were identified, resulting in only 10
canonical structures.
CONCLUSIONS: Despite the potential for diversity, only a minority of V-H an
d V-L germline genes are used by anti-D. Consequently, V-H and V-L pairings
and the resulting canonical structures are similarly restricted.