CD28 T-cell costimulatory molecule expression in pemphigus vulgaris.

BACKGROUND: CD28 superfamily of immune costimulatory molecules could play an important role in autotolerance control. CD28 costimulation seems to be necessary for regulatory T cell (Treg) activation and successive suppressive activities involved in autoimmunity protection. This study investigates CD28 expression, especially inducible costimulator fraction, on T lymphocytes in pemphigus vulgaris (PV) patients. METHODS: CD28 expression on T lymphocytes was assessed in 16 PV patients during acute attack. All patients and 10 healthy control subjects were tested for lymphocyte populations, T-cell subpopulations (T-CD4+, T-CD8+), Treg and CD28 expression on T-cell subpopulations. RESULTS: T, B and natural killer cells average values in PV patients were close to the control group values. Compared with control group, PV values showed lower Treg (2.2% compared with 4.7%), slightly decreased CD4+ CD28+ T cells (91% compared with 95%), higher CD4+ CD28- T cells (9% compared with 5%), decreased CD8+ CD28+ T cells (57% and 73%, respectively) and significantly enhanced CD8+ CD28- T cells (43% compared with 27%). CONCLUSIONS: These data suggest that Treg-mediated suppressor T-cell effects could be diminished in PV, together with an abnormal or ineffective subsequent helper T-cell suppression. CD28 high expression on helper T cells and low expression on suppressor T cells are arguments for a potential CD28 role in PV autoimmune response mechanism.

The immune response induced by a split influenza vaccine. Studies on cellular immunity.

The aim of this study is to evaluate the effects exerted in vivo upon the general reactivity of the immune system by a commercial split influenza vaccine produced by the Cantacuzino Institute, Bucharest-Romania. The vaccine was intramuscularly administered to 14 volunteers with no precedent of influenza vaccination and no major immune disorders. We have investigated in vitro the polyclonal proliferation of peripheral lymphocytes and the phagocytosis developed by peripheral granulocytes, before and three weeks after vaccination. Our experimental results indicate that the vaccine might have a modulatory action on peripheral leukocyte concentration induces the activation of polyclonal lymphocyte proliferation and of the phagocytosis potential of granulocytes. These effects are not dependent on the age of the vaccinees.

[The action of the supernatants from human lymphocyte cultures on E-active rosette formation]. / Actiunea supernatantelor din culturi de limfocite umane asupra rozetarii E active.

Lymphocytes separated from 20 normal subjects were introduced in two rosetation systems: the first was modulated rosetation (REM) with phytohemaglutinina (PHA), concanavalina A (Con. A). Mycobacterium tuberculosis (Mbt), and tumoral extract from ocular malignant melanoma (ET-MMO): the second was E-active modulated rosetation with supernatants from human lymphocyte cultures stimulated with PHA, Con A, Mbf and ET-MMO (REM-S), he average values of percentages of rosettes forming cells in the two systems REM and REM-S are comparable. We may assume the existence of some modulating factors which operate in the same manner on the functionality of T-lymphocyte in the two systems (REM and REM-S).

[Functional E rosette study pre and post laser treatment in malignant ocular melanoma]. / Explorare prin rozetare E "functionala" pre si post tratament laser în melanomul malign ocular.

For 11 patients with ocular malignant melanoma (OMM) suspicion, before and after laser photocoagulation therapy, by E rosette test were studied. A higher activation and sensitisation to OMM antigen was obtained after laser therapy in 9 patients. These results suggest the influence of laser treatment on lymphocyte function by "revealing" the physiological reactivity. Our results point out the "functional" E rosette test is useful for OMM diagnosis and therapy, as an indicator for disease prognosis.