[The effect of the collagen tripeptide fragment (GER) on the adhesion and spreading of fibroblasts depends on the properties of adhesive surface].

The effect of collagen tripeptide fragment GER on the adhesion and spreading of mouse embryonic fibroblasts STO to different substrates--polystyrene plastic and immobilized on plastic poly-L-lysine, fibronectin or gelatin was studied. Tripeptide GER has been found to participate in the regulation of fibroblast adhesion and spreading. Therewith, the tripeptide effect value on cell response was dependent both on the mode of tripeptide addition to culture medium and on the type of used substrate. During coincubation of fibroblasts with the tripeptide the stimulation of cell attachment and spreading to untreated plastic and plastic coated with fibronectin or gelatin was observed. At the same time the tripeptide did not change cell adhesion to immobilized poly-L-lysine. Preincubation of cells with the tripeptide resulted in partial inhibition of fibroblast adhesion and spreading on fibronectin- and gelatin-coated substrata. In was shown that the extent of activation and inhibition of adhesive processes on fibronectin was higher than such ones on gelatin after tripeptide treating. The data obtained support the assumption about concerted action of tripeptide GER (activity of which was dependent both on the used concentration of the tripeptide and on the mode of tripeptide addition to culture medium) and chemical characteristics of substrate (polymers of styrene and L-lysine, ECM proteins in native (fibronectin) or partly denatured (gelatin) form) on the cell adhesion and spreading. The main targets on which the GER peptide may affect during the formation of cell-substrate interactions are discussed.

[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.

Peptides and their constituent amino acids influence the immune response and phagocytosis in different ways.

To elucidate the role of immunoactive amino acids (which are capable of stimulating the immune response) in the peptide regulation of antibody production and phagocytic processes we have studied the influence of some fragments of natural peptides and the amino acids included in them on the thymus-dependent immune response to sheep red blood cells (SRBC) and on the phagocytosis of Staphylococcus by murine peritoneal neutrophils. It has been found that the effects of amino acids, as well as of peptides that they form, on the immune response and on phagocytosis were diverse. Glutamic and aspartic acids, threonine and valine stimulated both the immune response and phagocytosis. Glycine and isoleucine influenced neither the immune response nor phagocytosis, whereas lysine, proline, tyrosine and leucine did not influence the immune response, but enhanced the phagocytic activity of neutrophils. Arginine inhibited the immune response but stimulated phagocytosis. Peptide TTKD section (the fragment 77-80 of murine Thy-1-antigen) contained in C- and N-terminus amino acids (T and D) which stimulated the antibody production and phagocytosis, and lysine (K) which stimulated phagocytosis only, enhanced both processes. Peptides LGIP and PYIK (the fragments 49-53 and 66-69 of murine Thy-1 antigen) which contained both immunologically inert amino acids (L, G, I, P, Y, K) and phagocytosis stimulating amino acids (L, Y, P, K) influenced neither the immune response nor the phagocytic activity of neutrophils.(ABSTRACT TRUNCATED AT 250 WORDS)

[Use of tuftsin in experimental leprosy]. / Primenenie taftsina v éksperimental'noi leprologii.

The effect of tuftsin was studied in vivo using CBA mice infected with M. leprae by Shepard's technique and in vitro using macrophage-like cell line P. 388 (Co-cultivated with M. leprae) and the cultivated leproma tissue. It was found out that tuftsin acted as a stimulator of M. leprae multiplication in foot-pads of mice and as a prolongator of M. leprae survival in the cells of macrophage-like cell line P .388. It is concluded that using tuftsin might be useful in view of studying different aspects of experimental leprosy.

[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.

[The effect of synthetic protein fragments on humoral immune response]. / Vliianie sinteticheskikh fragmentov belkov na gumoral'nyi immunnyi otbet.

Effect of some protein and immunopeptide synthetic fragments on the humoral immune response has been studied. Some investigated peptides are shown to influence the antibody genesis at the secondary immune response to T-dependent antigen (bovine serum albumin) in mice. The serum antibody level specific for the bovine serum albumin is measured by enzyme-linked immunosorbent assays (ELISA). Possible mechanisms of the influence of such peptide fragments on the immune system is discussed.

[Morphologic characteristics of leproma cell cultures from humans and experimental animals and the effect on them of antileprotic preparations]. / Morfologicheskaia kharakteristika kul'tur kletok leprom cheloveka i éksperimental'nykh zhivotnykh i vliianie na nikh protivoleproznykh preparatov.

Leproma pieces obtained from leprosy patients and M. leprae-infected animals were cultivated by the method of primary explantation. It is noted that the development of a monolayer from macrophages overloaded with M. leprae is a characteristic common to the lepromas of various origin. Antileprosy activity of the drugs under study was assessed by the rate of decrease in mycobacterial load of macrophages. Species features of cultivated lepromas from man, nine-banded armadillo and mouse are characterised. While cultivating lepromas from leprosy patients the peculiarities of tissue culture organization are found out representing immune status and prognosis of specific therapy.

[Immunomodulating and analgesic activity of synthetic fragments of various proteins and immunopeptides]. / Immunomoduliruiushchaia i anal'geticheskaia aktivnost' sinteticheskikh fragmentov razlichnykh belkov i immunopeptidov.

The biological activity of certain new peptides synthesized by the classic methods of peptide chemistry is investigated. The characteristic feature of these peptides is that they are parts of the sequences of many naturally occurring proteins and immunopeptides (beta-lactoglobulin, vicilin, B-hordein, gamma-gliadin, histones, Thy-I-antigen, thymosin beta, leukocyte interferon, neutrophil peptides and others) tested by the computer methods. Most of the investigated peptides are shown to enhance E-rosette-forming activity of human T-lymphocytes and to possess the analgesic activity. In some cases the analgesic effect was antagonized by naloxone. The possible mechanism of appearance of such peptide fragments and their biological role in human organism is discussed.