Camel heavy-chain antibodies: diverse germline V(H)H and specific mechanisms enlarge the antigen-binding repertoire.

ABSTRACT: The antigen-binding site of the camel heavy-chain antibodies devoid of light chain consists of a single variable domain (V(H)H) that obviously lacks the V(H)-V(L) combinatorial diversity. To evaluate the extent of the V(H)H antigen-binding repertoire, a germline database was constructed from PCR-amplified V(H)H/V(H) segments of a single specimen of Camelus dromedarius. A total of 33 V(H)H and 39 V()H unique sequences were identified, encoded by 42 and 50 different genes, respectively. Sequence comparison indicates that the V(H)Hs evolved within the V(H) subgroup III. Nevertheless, the V(H)H germline segments are highly diverse, leading to a broad structural repertoire of the antigen-binding loops. Seven V(H)H subfamilies were recognized, of which five were confirmed to be expressed in vivo

SUBMITTER: Nguyen VK 

PROVIDER: S-EPMC305632 | biostudies-literature | 2000 Mar

REPOSITORIES: biostudies-literature