Myelopeptides: new immunoregulatory peptides.

Bone marrow cells of various animal species and humans produce a group of bioregulatory peptides called myelopeptides (MPs). MPs have been isolated and purified, and their physico-chemical properties have been investigated. MPs have a wide spectrum of functional activities: immunoregulatory, differentiating, and opiate-like. A new immunocorrective drug, Myelopidum, which is used effectively in clinical practice for treating diseases accompanied by immunodeficiency, has been created on the basis of MPs. Administration of Myelopidum after surgery prevents 50% to 70% of postsurgical complications, particularly postsurgery pneumonia, and also normalizes the number and balance of T-helper cells, T-suppressor cells, and B-lymphocytes in patients with chronic pulmonary diseases, resulting in a beneficial clinical effect, including a significant prolongation of remission periods. Myelopidum is also used in veterinary medicine for prophylaxis and treatment of pneumonia and enteritis in newborn and young animals. The primary structure of several myelopeptides is established. The functional activities of two, MP-1 (Phe-Leu-Gly-Phe-Pro-Thr) and MP-2 (Leu-Val-Val-Tyr-Pro-Trp), are being investigated.