Immunological studies on a yeast peptido-galactomannan - Nature of antigenic determinants reacting with rabbit antisera and those involved in delayed hypersensitivity in guinea pigs - Lee, W.-L.; Lloyd, K.O. (Elsevier)
The antigenicity of the peptido-phosphogalactomannan (PPGM) of Cladosporium werneckii and the carbohydrate and peptide moieties isolated from it were studied in rabbits and guinea pigs. In rabbits, the antisera produced against whole C. werneckii cells reacted only with the carbohydrate portions of the antigen. The major portion of the antibody was directed towards the long phosphogalactomannan carbohydrate chains. O-Acetyl substituents were shown to play important roles in the determinants on these chains since selective removal of these groups eliminated their reactivity with antibody. A relatively small amount of the antibody response was directed towards the more numerous, short, mannose-containing chains. Concanavalin A, on the other hand, precipitated the polymer by virture of its reactivity with these units and not with the phosphogalactomannan chains.Delayed type (cell-mediated) immunity to C. werneckii was studied in guinea pigs. PPGM was able to elicit strong delayed skin-tests as was a peptide-rich fraction derived from PPGM by mild acid hydrolysis. Pure carbohydrate chains of PPGM were completely inactive. In contrast, two of the modified peptides derived from PPGM were able to elicit a response although they were less active than PPGM. It was concluded that the determinants responsible for delayed hypersensitivity reside in the peptide portion of the antigen but that the technique used to isolate the peptides (alkaline β-elimination) partially destroyed the determinants.
http://dx.doi.org/10.1016/0003-9861(75)90072-7
Keywords: W; V; U