RESUMO
The first chicken immunoglobulin light (L) chain allotypic specificity (L-1.1) to be described that was present on IgM, 7S Ig, Fab, and L chains was detected by radioimmunoassay. The gene controlling the expression of L-1.1 is inherited in a simple Mendelian fashion at an autosomal locus and is unlinked to a constant region heavy chain locus, four blood group loci and three loci determining lymphocyte cell surface alloantigens.
Assuntos
Alótipos de Imunoglobulina/genética , Cadeias Leves de Imunoglobulina/genética , Animais , Sítios de Ligação , Ligação Competitiva , Galinhas , Mapeamento Cromossômico , Ligação Genética , Imunoglobulina G , Imunoglobulina M , RadioimunoensaioRESUMO
Low concentrations of allotypic specificity CS-1.1 were detected in the sera of two inbred chicken lines [University of California, Davis (UCD) 7 and Regional Poultry Research Laboratory 15I4] previously reported to lack this specificity. The CS-1.1 alloantigen in 15I4 chickens has the same specificity as the major allotype in a line of chickens (UCD 2) in which it was initially defined. In 15I4 chickens, CS-1.1 allotype is present on a population of molecules distinct from those which carry the major allotype; thus a second 7S Ig H chain locus, CS-2, is proposed. The concentration of CS-1.1-bearing molecules determined by two different methods was 7 microgram/ml and 230 microgram/ml in 15I4, whereas UCD 2 chickens had 4 mg/ml of CS-1.1 molecules. The levels of CS-1.1 inhibitory activity in 15I4 birds remained relatively constant over a 30-day period. The presence of two 7S Ig populations in 15I4 chickens may be interpreted as evidence either for 7S Ig subclasses with shared allotypes or for a pseudoallelic organization of genes controlling expression of 7S Ig H chains. The results were consistent with the presence of redundant C region genes, differing in allotypes, whose expression is under the control of an as yet undefined regulatory mechanism.
Assuntos
Alelos , Alótipos de Imunoglobulina , Imunoglobulina G/genética , Cadeias Pesadas de Imunoglobulinas , Animais , Sítios de Ligação de Anticorpos , Ligação Competitiva , Galinhas , Epitopos , Técnicas de ImunoadsorçãoRESUMO
A survey of 47 inbred or partially inbred chicken lines derived from five sources in the United States and Europe revealed considerable genetic polymorphism in the structural gene (CS-1) responsible for the production of the predominant chicken 7S Ig heavy chain. A minimum of 10 alleles of the CS-1 gene were detected as unique combinations or phenogroups of CS-1 specificities. A system of nomenclature for CS-1 alleles was developed and six homozygous lines were designated as prototype lines. The remaining four CS-1 alleles occurred only in lines that were polymorphic for 7S Ig allotypic specificities.
Assuntos
Genes , Alótipos de Imunoglobulina , Imunoglobulina G , Isoantígenos , Terminologia como Assunto , Alelos , Animais , Galinhas , Reações Cruzadas , Epitopos , Homozigoto , Polimorfismo GenéticoRESUMO
A survey of 48 inbred lines derived from five sources in the United States and Europe revealed considerable genetic polymorphism of the CS-1 gene. A minimum of ten alleles were detected as unique combinations of CS-1 specificities. The relationship of some of the alleles would indicate that intracistronic recombination may have played a role in the production of some of the polymorphism.
Assuntos
Galinhas/imunologia , Alótipos de Imunoglobulina , Imunoglobulinas/genética , Polimorfismo Genético , Alelos , Animais , Evolução Biológica , Galinhas/genética , Genes , Ligação Genética , Fragmentos de Imunoglobulinas/genética , Imunoglobulina G/genética , Região Variável de Imunoglobulina , Papaína/metabolismo , Recombinação GenéticaRESUMO
An alloantiserum recognizing a genetic marker (CM-1.4) on chicken 17S Ig was generated by immunizing jungle fowl with Salmonella O-anti-Salmonella O (UCD 3) agglutinates. Specificities CM-1.4 and M1a were present on 7S subunits and H chains based on their ability to inhibit in RIA the binding of alloantibody (anti-CM-1.4 or anti-M1a) to UCD 3 125I-17S Ig. CM-1.4 appears to be fully expressed on 7S subunits but is altered on H chains. In contrast, anti-M1a bound both 7S subunits and H chains with decreased avidity indicating that the M1a specificity was altered in both preparations. Since CM-1.4 and M1a are present on 17S Ig H chains, and absent from 7S Ig, they probably represent allotypic markers in the constant region of 17S Ig H chains. Having assigned two 17S Ig allotypic specificities to H chains, we propose that the locus controlling their expression be called CM-1. Based on the distribution of the CM-1.4 and M1a allotypes in inbred lines of chickens, 3 alleles are defined at the CM-1 locus.
