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An experimental model of immunological deficiency obtained by treating mice for 6 months with serum of human blood drawn from different healthy individuals has been studied. The results show that an alteration of the circulating lymphocyte population with alterations of the ratio CD4+/CD8+ appeared In mice stimulated for a long period with immunogens. Mice treated for 2-4 months showed an increase in B lymphocytes and a decrease in the total number of T lymphocytes, with a decrease in CD4+ lymphocytes and an increase in CD8+ lymphocytes. After 4 months, the CD8+ lymphocyte population started to decrease, with a ratio of CD4+/CD8+ reaching almost 1. In animals treated for 2-3 months, the mean survival time (MST) following experimental infection with Salmonella typhimurium presented a decrease lo 5 days, and after 5-6 months of treatment presented a decrease to 3-2.5 days, The bacteraemia was modified in comparison with controls. Prolonged exposure to antigens also induced lymphocyte apoptosis: cells of animals treated for 4-6 months presented increased levels of apoptosis with a percentage that reached 30-35%. A semiquantitative evaluation of the level of heal shock protein (hsp) in splenic lymphocytes showed an increase in the presence of hsp60 and hsp70 in the first 3 months of treatment, which then remained constant for up to 6 months. [ABSTRACT FROM AUTHOR]

Describes the results in a mouse model where ethanol (ETOH) was administered in a liquid diet. Aspects of the specific and non-specific immunologic responses; Increase in mortality with an increase in the number of circulating bacteria; Decrease in adherence and migrational capacity of polymorphonuclear leukocytes; Decrease in response of lymphocytes to polyclonal stimuli.

The aim of this study was to verify whether Salmonella typhimurium porins can affect the expression of interleukin-1 (IL-1) and interleukin-6 (IL-6) genes. Human monocytes were treated with porins, and total RNAs were analysed by Northern blotting to evaluate the expression of IL- 1α IL-1β and IL-6 in both treated and untreated cell cultures. Porins induced a significant increase in IL-1 and IL-6 transcripts. This increase was related to the dose of porins, and it peaked 5 hr after treatment. The same results were obtained when polymyxin B was added to the porin preparation to eliminate eventual traces of lipopolysaccharide (LPS) associated with porins. The porins-mediated increase in interleukin transcripts did not require de novo protein synthesis, and it was because of the enhanced half-life of IL-1 and IL-6 mRNAs, rather an increased rate of gene transcription. These data suggest that porins may affect inflammatory and immunological responses by enhancing the expression of cytokine genes. [ABSTRACT FROM AUTHOR]