Andrey Simbirtsev

Effect of mild chronic stress, as a model of depression, on the immunoreactivity of C57BL/6 mice

Numerous studies correlate the state of depression with some abnormalities in the immune response, such as increased numbers of white blood-cells, alterations in sub-populations of leucocytes, suppression of cytotoxic activity of natural-killer cells, increased levels of some autoantibodies and acute-phase proteins. Some of these changes have been attributed to autoimmunological reactions. While the possibilities to evaluate some reactions in depressed patients are limited, an animal model of depression could well simulate this clinical situation, and the chronic mild state of stress is a well accepted one. After undergoing stress for three-weeks, C57BL/6 mice demonstrate in the present study a decrease in thymus weight, as well as increased interleukin-1 and decreased interleukin-2 production. Splenocytes of the depressed mice exert a decrease in natural-killer-cell activity, in the proliferative response to Concanavalin-A, interleukin-1 and anti-CD3 monoclonal antibodies and an increase in the proliferative response to lipopolysaccharides and pokeweed mitogens. Our results also suggest that chronic stress-induced activation of suppressor cells in the spleen, due to elimination of CD8+ cells, increase the proliferation of splenocytes in response to mitogens of T cells.

Interleukin-1-glucocorticoid hormone interrelationship in the regulation of the immune response

: Influence of synthetic peptides identical to fragments of natural human immunodeficiency virus (HIV) glycoproteins gp 120 and gp 41, on luminol-enhanced chemiluminescence (CL) of human neutrophils has been studied. It was established that some of peptide analogs of gp 120 and gp 41 immunodominant regions are able to suppress spontaneous CL: but when being used with dimethylsulfoxide they dramatically stimulate it and deteriorate opsonized zymosan-induced CL. Conclusions about the necessity of possible side effects considering during use of peptide vaccines against HIV have been made. It is also possible to explain some neutrophil dysfunction in HIV infected subjects as the result of HIV glycoproteins direct influence on this cells.

Immunocytochemical analysis of interferon-1β production by human monocytes

Interleukin-1/5 (IL-1/6) is a cytoldne with molecular weight of about 18 ldlodaltons, which is synthesized mainly by monocytes/macrophages in response to their activation during development of immune and inflammatory reactions in vivo. Production of IL-1 has hitherto been studied by analysis of its content in L-conditioned culture medium, in cell lysates, and also by assessment of the level of expression of IL-1 genes on the basis of accumulation of specific mRNA in the cells. Meanwhile, it has been shown to be possible in principle to analyze the IL-1 concentration directly in the cytoplasm of stimulated monocytes, by using immunocytochemical methods [3, 5], which means that its production can be studied at the cellular level. By using a method of immunocytochemical detection we have studied the dynamics of IL-lfl production by human peripheral blood monocytes.

Preparation and properties of interleukin-1 from human blood monocytes

: Among different tested substances LPS-containing preparations were found to be most effective inducers of secretory interleukin-1 in human peripheral blood monocytes in vitro. IL-1 from supernatant of prodigiozan- + con A-stimulated monocytes had a MM of 18-20 KD and pI of 5.2-5.4 and 6.8 revealing an equal comitogenic activity and of 6.0 (minor peak).