Different mitogenic activity of soluble and insoluble staphylococcal protein A (SPA).

The response to SPA and Staphylococcus strain Cowan I (StaCw) of highly purified populations of peripheral blood and tonsil human lymphocytes was investigated. Purified T lymphocytes isolated from perpheral blood by E-rosetting were unable to respond in vitro to StaCw. Highly purified B-cell populations from tonsils did not show any proliferative response in the presence of soluble SPA. The addition to highly purified B-cell suspensions from human tonsils of increasing concentrations of autologous T lymphocytes did not induce any increase of thymidine uptake in the presence of StaCw. However, it was able to restore a marked proliferative response of the B-cell cultures to soluble SPA, even though mitomycin-treated T lymphocytes were added. The low response of highly purified peripheral blood T lymphocytes to soluble SPA could be potentiated by the addition of autologous mitomycin-treated B cells, whereas the unresponsiveness of purified T lymphocytes to StaCw was not affected. Mitogenic activity of SPA coupled to Sepharose beads was different from that of soluble SPA and paralleled that of StaCw. These data strongly suggest that insoluble SPA is a T-cell-independent B-cell mitogen in man, whereas soluble SPA, like PWM, exerts its activity on B cells only in the presence of T cells

Association between "sarcoidosis-like" disease and common variable immunodeficiency (CVI): a new CVI variant showing an activation of the immune system

BACKGROUND: Particular interest has been recently addressed to the association between a Granulomatous Sarcoidosis-like Disease (GSa-LD) and Common Variable Immunodeficiency (CVI). METHODS: The present paper discusses the clinical and immunopathological findings of the association between CVI and GSa-LD, based on four patients, whose clinical course was followed for about seven years. The lung involvement was studied by high resolution chest computed tomography scansion, classical parameters of lung function and diffusion lung carbon monoxide. All patients underwent bronchoalveolar lavage in order to exclude tuberculosis infection by culture analysis and polymerase chain reaction as well as to investigate the presence of active alveolitis. RESULTS: The clinical progression of patients were consistent with that reported in the literature confirming some distinct features in comparison with patients with CVI. In particular, patients with CVI/GSa-LD exhibited a reduced rate of respiratory infectious diseases, despite low levels of circulating immunoglobulins, and displayed a lower ability to develop bronchiectasies. Accordingly, the absolute number of circulating CD8+DR+, but not of CD4+DR+ T cells in CVI-GSa-LD patients were significantly lower than in the group of patients suffering from CVI alone. Moreover, patients with CVI/GSa-LD did not develop lung fibrosis (at least for the period of our follow-up) even though they show an active lymphocytic alveolitis in the bronchoalveolar lavage and displayed an higher degree of monocyte-macrophage activation. CONCLUSIONS: A better definition of the molecular and cellular mechanisms involved in the development of systemic macrophage and T cell activation in immunodeficiency patients is required, in order to clarify the pathogenesis of sarcoidosis-like disease in CVI

Evaluation of a novel particle-based assay for detection of autoantibodies in idiopathic inflammatory myopathies.

13sinonenoneCavazzana I, Richards M, Bentow C, Seaman A, Fredi M, Giudizi MG, Palterer B, Pratesi F, Migliorini P, Franceschini F, Satoh M, Ceribelli A, Mahler M.Cavazzana, I; Richards, M; Bentow, C; Seaman, A; Fredi, M; Giudizi, Mg; Palterer, B; Pratesi, F; Migliorini, P; Franceschini, F; Satoh, M; Ceribelli, A; Mahler, M