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Peripheral blood natural killer (NK) cell activity of a group of 10 healthy non-atopic volunteers was reduced following the topical application of 15 g of 0.1 % betamethasone valerate ointment to the skin nightly for 1 week. In contrast, no such effect was observed when the inactive base of the steroid ointment was used. NK cell activity dropped significantly by day 7 (P<005) and then recovered, although NK cell activity at day 22 was still lower than that observed at the start of the experiment. These findings suggest that topically applied steroid is absorbed in sufficient amounts to cause a systemic effect on NK cell function. This may have implications in a number of dermatological disorders, including atopic dermatitis, where topical steroids form the mainstay of treatment. [ABSTRACT FROM AUTHOR]

We have investigated the immune responses in vitro of uraemic patients undergoing regular haemodialysis or continuous ambulatory peritoneal dialysis. Twenty-five healthy subjects were also studied as controls. In uraemic patients, the number of T and B lymphocytes were within the normal range, but proliferative respones to phytohaemagglutinin (PHA) were impaired. Spontaneous immunoglobulin plaque forming cell (PFC) responses by peripheral blood mononuclear cells (PBMC) from uraemic patients were significantly lower than those of healthy subjects. The PFC response of uraemic PBMC to the T cell independent polyclonal B cell activator (PBA) Epstein-Barr virus (EBV) was comparable to the response of the healthy subjects, indicating that uraemic B cells are still capable of synthesizing immunoglobulin. Pokeweed mitogen (PWM) induced PFC responses of uraemic PBMC were also normal, whereas the response to another T cell dependent B cell activator, Staphylococcus aureus Cowan I (SAC), was very low. Addition of indomethacin to PWM- and SAC-activated cultures of uraemic PBMC enhanced the PFC response to SAC, but had little effect on the PWM response. As full differentiation of B cells in response to SAC depends on helper T cells, we conclude that a defect in T lymphocyte function accounts for the reduced spontaneous and SAC induced production of immunoglobulin by uraemic PBMC. This defect may be mediated by an indomethacin-sensitive mechanism. [ABSTRACT FROM AUTHOR]

The development of cell-mediated immunity to paternally-derived foetal transplantation antigens in parous mice has been assessed by two techniques: skin grafting in an H-2 incompatible mating and a local graft-versus-host assay in an H-2 compatible mating. (1) Lymphoid cells from BALB/c females, parous one to seven times to C3H/Bi males, were injected i.p. into syngeneic males or females which were then grafted with skin from the paternal strain. A slightly accelerated rejection in the adoptively immunized recipients was observed. (2) Lymphoid cells from CBA females, parous one to five times to AKR males, were injected into the feet of young F1 hybrid recipients. The degree of popliteal lymph node enlargement was significantly greater in recipients of cells from parous than from virgin donors. Results using both techniques demonstrated that the development of cell-mediated immunity to paternal transplantation antigens is a regular feature in parous mice and that the degree of immunity increases with successive interstrain pregnancies. [ABSTRACT FROM AUTHOR]

Normal, 'deprived' (thymectomized, irradiated, bone marrow injected) and 'reconstituted' (thymectomized, irradiated, bone marrow injected, thymus grafted) CBA mice have been tested for their ability to respond to the contact sensitizing agent, oxazolone. The test involved painting the ear of a previously sensitized animal and subsequently measuring alterations in ear thickness. .A sensitized condition could be detected in the normal and reconstituted mice after either one or two sensitizing contacts with oxazolone but in the deprived animal little or no sensitivity could be detected. It is concluded, that the thymus influences the development of contact sensitivity probably by provision of a population of reactive cells. [ABSTRACT FROM AUTHOR]