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L A Stepanova

Publications and source records attributed to L A Stepanova.

11 recordsLinked to original sources
PubMed1993

Kinetic approach and estimation of the parameters of cellular interaction between the immunity system and a tumor.

A method is suggested to estimate multi component dynamic systems, which permits, with the help of the computer-calculated kinetic curves, to obtain information about the possible mechanisms of the system component interaction. The method is based on the structural and parametrical identification of mathematical models presented in the form of a system of nonlinear differential equations, using a multi-criterial approach. Using experimental data of studies on growth kinetics and regression of multicellular tumor EMT6 line spheroids in the mouse allogenic system and the immune system cell accumulation in spheroids a mathematical model has been developed of the cellular interaction process in a spheroid. It has been stated that the rate of macrophage and neutrophil accumulation in a spheroid depends on the amount of tumor cells and is determined by the hyperbolic law (as analogous to the Michaelis-Menthen kinetics), while the accumulation of immune lymphocytes in a tumor is determined besides that by the three-cellular cooperation of lymphocytes, macrophages and tumor cells. According to the model, the inhibition of the process of neutrophil and lymphocyte (but not of macrophages) accumulation is realized through the auto-suppression mechanism. The numerical values of the process parameters, which characterise the rates of accumulation, cellular death in a tumor and of local cellular interactions intensity are obtained.

Cell Communication↗
PubMed1990

[A method of determining leukocyte adhesion in autoplasma].

The author suggests a method for assessment of the peripheral blood leukocyte adhesive properties by making use of glass syringes and fit for clinical practice. The technique is reproducible, informative, simple. Seasonal variations of polymorphonuclear and mononuclear leukocyte adhesive capacity were detected, that should be borne in mind when estimating the peripheral blood cell functional activities in various diseases.

Adult↗
PubMedDate not supplied

[Specific immune response to vaccination with an inactivated flue vaccine depending on prevaccine status and age of the person vaccinated].

Specific antibody immune response to vaccination with commercial inactivated trivalent vaccine A(H1N1) + A(H3N2) + B (IgA, IgG, IgG, subclasses G1, G3, G4, and accumulation of antiCD8) was studied in subjects aged 20-95 years. The initial immune status before vaccination is significant for a positive immune response to the vaccine. Subjects responding to immunization by an increment in specific IgG had a much lower prevaccination level of these antibodies than subjects without these Ig conversion. Antibody immune response to vaccination depended on patient's age. All vaccinees aged 20-25 years developed an increment in IgG to at least one of influenza antigens used. Specific postvaccinal immune response to inactivated influenza vaccine included accumulation of G1, G3, and A antibodies, but not G4 or E antibodies. This latter fact suggests the absence of sensitizing effect of vaccination. In elderly subjects an increment in G1, G3, and A antibodies may not involve an increase in the total level of IgG. In part of elderly subjects secretion of specific antibodies was observed in the presence of increased concentration of antilymphocytic antibodies (antiCD8), indicating a possibility of autoimmune reactions in subjects of this age after injection of inactivated influenza vaccine.

Adult↗
PubMedDate not supplied

[Humoral and local immune response to the influenza vaccine in people of old and young ages].

The specific features of the humoral and local immune responses to influenza vaccines were comparatively studied in people of different age groups. A total of 79 elderly people (aged 67-89) and 80 young people (aged 18-27) were immunized according to one of the four schemes: live cold-adapted reassortant trivalent influenza vaccine (LIV), administered intranasally; inactivated split trivalent influenza vaccine (IIV), administered parenterally; a combination of both above vaccines; and placebo. IIV was found, as compared to LIV, to stimulate more effectively the production of circulating antihaemagglutinins as well as of IgG,-, Ig1-, and Ig3-AT in young persons, while LIV has advantages before IIV in stimulating the synthesis of these immunoglobulins in the elderly. LIV has advantages before IIV in stimulating the synthesis of secretory IgA-AT irrespective of an age of the immunized persons. The combined immunization of the elderly by both vaccines increases the quantitative parameters of the humoral and local responses up to the level of intensity observed in young people. The obtained data are indicative of the possibility of correcting the immune response in the high-risk elderly in respect to influenza infection.

Adolescent↗