Analyses of chicken immunoglobulin light chain cDNA clones indicate a few germline V lambda genes and allotypes of the C lambda locus.

Abstract

cDNA libraries of chicken spleen and Harder gland (a gland enriched with immunocytes) constructed in pBR322 were screened by differential hybridization and by mRNA hybrid‐selected translation. Eleven L‐chain cDNA clones were identified from which VL probes were prepared and each was annealed with kidney DNA restriction digests. All VL probes revealed the same set of bands, corresponding to about 15 germline VL genes of one subgroup. The nucleotide sequences of six VL clones showed greater than or equal to 85% homology, and the predicted amino acid sequences were identical or nearly identical to the major N‐terminal sequence of L‐chains in chicken serum. These findings, and the fact that the VL clones were randomly selected from normal lymphoid tissues, strongly indicate that the bulk of chicken L‐chains is encoded by a few germline VL genes, probably much less than 15 since many of the VL genes are known to be pseudogenes. Therefore, it is likely that somatic mechanisms operating prior to specific triggering by antigen play a major role in the generation of antibody diversity in chicken. Analysis of the constant region locus (sequencing of CL gene and cDNAs) demonstrate a single CL isotype and suggest the presence of CL allotypes.

Regulation of HSP70 gene expression during the life cycle of the parasitic helminth Schistosoma mansoni

“…Other procedures, including mRNA translation in wheatgerm extract, immunoprecipitation of cell-free products, SDS/polyacrylamide gel electrophoresis, mRNA hybrid selection followed by translation and immunoprecipitation, and Northern blots using gels containing formaldehyde, were carried out according to published procedures (Maniatis et al, 1982;Parvari et al, 1987).…”

Somatic diversification of chicken immunoglobulin light chains by point mutations.

“…The CA cDNA probe (where C = constant) used starts on the 86th arginine codon of the CA chain, extending 300 base pairs (bp) to the end of the 3' untranslated region. It was prepared from the chicken L-chain cDNA, clone H-18, whose sequence was published previously (3). DNA nucleotide sequences were determined at least twice by the chaintermination method (9).…”

“…The contribution of the germ-line element for the diversification of chicken immunoglobulin light (L) and heavy (H) chains is rather limited, because their variable (V) regions are encoded by only one VL subgroup (2,3) and one VH subgroup (4). Furthermore, the entire L-chain repertoire is derived from a single V-J rearrangement (where J = joining) because there is 1 J gene and only 1 functional VAl gene, and the remaining 25 are pseudo-VA-genes that serve as donor sequences to diversify the rearranged VA1 gene by gene hyperconversion (2,5,6).…”

Fundamental Characteristics of the Immunoglobulin VH Repertoire of Chickens in Comparison with Those of Humans, Mice, and Camelids

“…Despite the use of this very simple (essentially single framework [FW]) germline v-gene system (6,17,(24)(25)(26), chickens have a very adaptable Ab repertoire that is capable of generating highaffinity interactions with a broad range of Ags including proteins, peptides, and haptens (3,(27)(28)(29). This broad Ag recognition capability, combined with simple isolation of multiortholog crossreactive mAbs via technologies such as phage display (3,30), have made chicken Abs a potentially valuable source of Ab therapeutics.…”