[Effects of synthetic fragments of defensins on aggregation and adhesion of epitheliolike cells].

Normal course of processes of regeneration and epitheliazation of damage tissues has been shown to be based on the capability of cells participating in these processes for selective adhesion. In the case of the complete or partial absence of this capability in the cells-participants of the wound healing process, the so-called non-healing wounds appear. In this connection, it remains actual to search for natural agents promoting healing of chronic non-healing wounds. In the present work, we studied effects of synthetic fragments of leukocytic antimicrobial peptides defensines--GER, FGER, and GERA--on aggregation and adhesion of epitheliolike cells of the CHO-K1 line. These peptides have been established to have aggregate-stimulating properties; besides, they enhance adhesion of the cells to the untreated plastic and inhibit fibronectinmediated cell adhesion. Possible pathways of regulation by peptides of processes of intercellular and cell-matrix interaction are discussed as well as ways of release of these compounds in an organism and their functional role in an organism.

[Different effects of peptides and their amino acids on antibody production and phagocytic activity of the neutrophils in mice]. / Neodnoznachnost' deistviia peptidov i sostavliaiushchikh ikh aminokislot na antitelogenez i fagotsitarnuiu aktivnost' neitrofilov u myshei.

The effects of some natural polypeptides fragments and amino acids which were incorporated in them on the thymus-dependent SRBC immune response and on the phagocytosis of Staphylococcus by murine peritoneal neutrophils were compared. It was found that the peptides LGIP and PYIK which consisted of those amino acids that stimulated phagocytosis but did influence the immune response (K, P, Y, L) did not change the immune response as well as phagocytosis. The peptides TKPR, TTKD and LGIPE which included those amino acids that were able to stimulate both immune response and phagocytosis (T, E, D) enhanced both activities. Nevertheless the peptide PYIKV containing valine (that stimulated the antibody production as well as phagocytosis) did not effect the immune response but enhanced the phagocytic index. The existence of two immunoregulatory systems--the peptide system and the amino acid one--was suggested.