Induction of an interleukin-1 receptor antagonist-like component produced from mouse spleen cells by bovine kappa-caseinoglycopeptide.

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.