ABSTRACT
Bovine kappa-caseinoglycopeptide (residues 106-169, CGP) completely inhibited the PHA-induced proliferation of mouse splenocytes when CGP was added simultaneously with PHA. The inhibitory effect, however, was reduced to about one-half when CGP was added after 24 h of cultivating the splenocytes with PHA or when anti-IL-1ra antibody was added simultaneously with PHA and CGP. On the other hand, CGP bound to mouse CD4+ T cells but not to CD8+ T cells. CGP suppressed IL-2 receptor expression of the PHA-stimulated mouse CD4+ T cells.
Subject(s)
CD4-Positive T-Lymphocytes/drug effects , Caseins/pharmacology , Glycopeptides/pharmacology , Receptors, Interleukin-2/biosynthesis , Animals , CD4-Positive T-Lymphocytes/cytology , CD4-Positive T-Lymphocytes/metabolism , Cattle , Cells, Cultured , Humans , Mice , Mice, Inbred C3H , Rabbits , Receptors, Interleukin-1/antagonists & inhibitors , Receptors, Interleukin-2/drug effects , Spleen/cytologyABSTRACT
Bovine kappa-caseinoglycopeptide (residues 106-169, CGP) bound to mouse plastic-adherent cells. A culture supernatant prepared from mouse spleen cells and plastic-adherent cells cultured with CGP significantly inhibited the lipopolysaccharide-induced proliferative response of mouse spleen lymphocytes. The inhibition of proliferation by the culture supernatant was completely overcome by the addition of the anti-interleukin-1 receptor antagonist antibody.
Subject(s)
Caseins/pharmacology , Glycopeptides/pharmacology , Receptors, Interleukin-1/antagonists & inhibitors , Sialoglycoproteins/biosynthesis , Spleen/drug effects , Animals , Cattle , Cell Division , Cells, Cultured , Interleukin 1 Receptor Antagonist Protein , Mice , Mice, Inbred C3H , Spleen/cytology , Spleen/metabolismABSTRACT
Bovine kappa-caseinoglycopeptides (i.e. residues 106-169, CGP) were prepared from kappa-casein digested with rennin and a commercial whey protein concentrate. CGP from whey protein concentrate was further divided into seven CGP fractions having different carbohydrate compositions using FPLC. Unfractionated CGP inhibited lipopolysaccharide (LPS)- and phytohaemagglutinin (PHA)-induced proliferative responses of mouse spleen cells and rabbit Peyer's patch cells. The unfractionated CGP also inhibited antibody responses to sheep red blood cells in mouse spleen cell cultures. However, seven CGP fractions having zero to five N-acetylneuraminic acid (NANA) residues had different inhibitory effects on both LPS- and PHA-induced proliferative responses of mouse spleen cells. The inhibitory effect on PHA-induced proliferative responses increased with increasing numbers of NANA residues, whereas that on LPS-induced proliferation was highest with the CGP fraction having two NANA residues. Both inhibitory effects decreased significantly after neuraminidase or chymotrypsin digestion. These findings indicate that both the carbohydrate (particularly the NANA residues) and the polypeptide portions are essential for inhibitory effects on LPS- and PHA-induced proliferative responses of mouse spleen cells.
