Immune-related edemagenic activity of glutamines and glutamic acid, components of immunomodulatory agents.

A number of compounds, in their structure similar to the immunomodulatory agent adamantylamide-L-alanyl-D-isoglutamine (AdDP), a desmuramyl analog of muramyl dipeptide (MDP), were compared with respect to their in vivo immunobiological activity. The agents were represented by adamantylamide-peptides or -amino acids differing principally in the nature of glutaminyl moieties. They were all able to induce inflammatory reaction which was prevented by anti-T-cell (TH) mAb, silica, indomethacin and dexamethasone. Responsible for this effect proved to be glutaminyl moieties (glutamine, isoglutamine, or glutamic acid), irrespective of their stereospecificity. Unlike the immunomodulatory molecule of AdDP, neither of the compounds and amino acids were able to stimulate production of antibodies in immunized animals, however.