Effect of moderate (40 degrees C) and intensive (43 degrees C) hyperthermia on spleen, lymph-node and thymus-derived murine lymphocytes in vitro

Effect of purified staphylococcal leukocidal toxins on isolated blood polymorphonuclear leukocytes and peritoneal macrophages in vitro

Bicomponent (fractions S and F) staphylococcal leukocidal toxins (Panton-Valentine leukocidin-Luk and haemolysin gamma-Hlg) were tested for in vitro activity against isolated polymorphonuclear leukocytes (PMNL) and peritoneal macrophages (PMF). For assessment of membrane permeability at subcytolytic concentrations of leukocidin (Luk-S + Luk-F) and haemolysin gamma (HlgA + HlgB) (8-1000 ng/ml), PMNL and PMF were radiolabelled (86Rb, 14C-amino-isobutyric acid (AIB) or 51Cr). All toxins tested caused lysis of human PMNL, although considerable differences were noted in the sensitivity of these cells to Luk and Hlg. Release of 51Cr (at 1000-5000 ng/ml), being a sign of irreversible cell damage and lysis, was preceded, at lower concentrations of the toxins (40 and 200 ng/ml), by the release of large amounts of low-molecular labels--86Rb and 14C-AIB. In another experiment, it was found that release of 86Rb from PMNL incubated with low concentrations of Luk (50 ng/ml) took place after 15-30 minutes of incubation, when no significant amounts of 14C-AIB or 51Cr were released. These findings support the concept of pore formation by staphylococcal leukocidal toxins in membranes of sensitive cells and indicate that a relatively short time is needed for the formation of these pores after binding of the Luk-S and Luk-F components to the membrane.

Effect of local hyperthermia on lymph immune cells and lymphokines of normal human skin

The effects of 3 h lasting local hyperthermia on immune cell traffic through the normal human skin to afferent lymphatics, cell phenotypes, responsiveness, and stimulatory properties were studied in eight men. Cells were harvested from lymph drained from foot skin. Heating the skin in a water bath of 44 degrees C (skin temperature 2 mm under the surface 39 degrees C) evoked an augmented traffic of mononuclear cells to lymph with preponderance of large, macrophage-like, Ia-positive cells, among them Langerhans cells. Lymphocytes obtained from the heated skin lymph revealed in cultured increased spontaneous blastic transformation rate, augmented responsiveness to phytohemagglutinin (PHA), and enhanced PHA-presenting properties to autologous peripheral blood mononuclear (PBM) cells. An increased stimulatory activity on allogeneic mixed lymphocyte reaction (MLR) was also observed. Lymph from heated skin augmented the PBM responsiveness to PHA and showed increased interleukin-1-like activity. Local heating of the skin is a potent signal initiating augmented traffic, and enhanced responsiveness and stimulatory activity of "passenger" immune cells. Their rapid nonspecific activation makes them indiscriminately active against a wide range of antigens before the specific response is developed.