Influence of streptolysin S on lymphocyte functions.

Streptolysin S, which was found to be cytotoxic for mouse and human lymphocytes and particularly for their T subpopulation, was also shown to affect some of the functions ascribed to T lymphocytes. In vitro studies demonstrated that streptolysin S-pretreated lymphocytes exhibited reduced responsiveness to phytohemagglutinin and decreased lymphokine production. Streptolysin S could also alter the immune response of mice in vivo. It induced suppression of the immune response to T-dependent antigen (SRBC) but had not influence on response to T-independent antigen (S III). The in vitro and in vivo studies suggest that streptolysin S can impair the function of T lymphocytes or, more precisely, of some subpopulation of T cells.

Immune responsiveness of irradiated mice reconstituted with complement receptor positive CLR+ or negative CLR--lymphocytes from spleen or bone marrow.

Spleen and bone marrow cells depleted of CRL cannot restore immune reactivity of irradiated mice to sheep red blood cells SRBC. The response to anti-SIII, a T-independent antigen does not change when irradiated animals are repopulated with spleen cells or spleen cells depleted of CRL. Spleen cells of 6-day-old mice having low number of CRL, in contrast to spleen cells of adult animals, could not reconstitute irradiated recipients.

T and B lymphocytes, immunoglobulins and complement components in bronchial asthma.

Sixty children, 7--15 years old, suffering from bronchial asthma and 44 healthy children, 12--14 years old, were studied for the percentage and the total count per mm.3 of T and B lymphocytes. Patients were classified into extrinsic atopic, mixed and intrinsic asthma. According to the clinical course mild and severe cases were analysed separately. The total and "active" T lymphocytes were detected by the ability to form nonimmune rosettes with sheep red blood cells. The B lymphocytes were estimated by the rosetting procedure with antibody mouse complement coated sheep erythrocytes. No decrease of the percentage or total count of T lymphocytes was observed, and an elevation of total count and percentage of active T cell rosettes was even seen in severe cases of extrinsic atopic asthma. The B cell percentage was decreased in severe atopic, mild intrinsic and mild mixed asthma but the total number was lowered only in the last group. The immunoglobulin A, G, M, D and E level, measured by the single radial immunodifussion test, was correlated neither to T cell nor B cell percentage. The complement components C1q, C4, C3, C3 proactivator and C5 were measured by the radial immunodufusion test in the plasma of some patients and controls. The C1q level was normal. An elevation of C4 in mild extrinsic, C5 in severe extrinsic and C3 in severe mixed asthma was seen. A decrease of C3 proactivator was observed in mild extrinsic and mixed asthma, and in three cases of intinsic asthma this was accompanied by lowering of C3, suggesting an activation of the alternative pathway.

The in vivo phagocytosis and intracellular killing of staphylococcal mutants by guinea pig peritoneal exudate cells.

The rate of phagocytosis and intracellular killing of staphylococcal mutants of different cell wall structure or those deprived of alpha-toxin production was studied in vivo in guinea pig peritoneal cavity. All mutants were ingested and killed at minor rates than standard S. aureus strains but only in the first hour of the observations.

Attempts to evaluate the role of the third complement component (C3) and complement receptor lymphocytes (CRL"+") in the induction of the humoral immune response.

It has been shown that spleen and bone marrow complement receptor lymphocytes (CRL"+") are responsible for T-dependent anti-SRBC response. This has been shown by comparison of the T-dependent anti-SRBC and T-independent anti-SIII response in irradiated mice repopulated with normal or CRL depleted spleen cell populations. Unseparated spleen cells obtained from animals immunized 48 h before with SRBC, and CRL depleted cell population from animals receiving T-independent antigens (levan, SIII) were shown to be predominantly stimulated when uptake of isotope labelled leucine or tymidine was studied. It was also shown that triggering of enhanced antibody production by T cell derived signal generated during GvH reaction is C3 dependent.

Anti-staphylococcal gamma hemolysin antibodies in rabbits with staphylococcal osteomyelitis.

Titers of antibodies against staphylococcal gamma hemolysin were estimated in 23 rabbits with experimental staphylococcal osteomyelitis and in 32 control animals. In all but three infected animals from 2- to 64-fold increases of the antibody titers were detected. Most of the control animals showed no changes in anti-gamma toxin antibody titers, but in two animals some increase was noted. The possible significance of these differences is discussed.