Prolonged Survival of Allografts Induced by Mycobacterial Hsp70 Is Dependent on CD4+CD25+ Regulatory T Cells

Background: Heat shock proteins (Hsps) are stress induced proteins with immunomodulatory properties. The Hsp70 of Mycobacterium tuberculosis (TBHsp70) has been shown to have an anti-inflammatory role on rodent autoimmune arthritis models, and the protective effects were demonstrated to be dependent on interleukin-10 (IL-10). We have previously observed that TBHsp70 inhibited maturation of dendritic cells (DCs) and induced IL-10 production by these cells, as well as in synovial fluid cells. Methodology/Principal Findings: We investigated if TBHsp70 could inhibit allograft rejection in two murine allograft systems, a transplanted allogeneic melanoma and a regular skin allograft. In both systems, treatment with TBHsp70 significantly inhibited rejection of the graft, and correlated with regulatory T cells (Tregs) recruitment. This effect was not tumor mediated because injection of TBHsp70 in tumor-free mice induced an increase of Tregs in the draining lymph nodes as well as inhibition of proliferation of lymph node T cells and an increase in IL-10 production. Finally, TBHsp70 inhibited skin allograft acute rejection, and depletion of Tregs using a monoclonal antibody completely abolished this effect. Conclusions/Significance: We present the first evidence for an immunosuppressive role for this protein in a graft rejection system, using an innovative approach - immersion of the graft tissue in TBHsp70 solution instead of protein injection. Also, this is the first study that demonstrates dependence on Treg cells for the immunosuppressive role of TBHsp70. This finding is relevant for the elucidation of the immunomodulatory mechanism of TBHsp70. We propose that this protein can be used not only for chronic inflammatory diseases, but is also useful for organ transplantation management.Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Financiadora de Estudos e Projetos (FINEP

Complicações arteriais da síndrome do desfiladeiro torácico Arterial complications of thoracic outlet syndrome

As manifestações clínicas da síndrome do desfiladeiro torácico são predominantemente neurológicas, sendo as complicações arteriais raras, mas potencialmente graves. Entre elas, devemos citar os aneurismas com complicações embólicas e a trombose. Os autores relatam o caso de uma mulher de 37 anos com costela cervical bilateral que apresentou embolia no membro superior direito originada de um aneurisma pós-estenótico da artéria subclávia direita, além de apresentar ectasia da subclávia esquerda também por compressão.<br>The clinical manifestations of thoracic outlet syndrome are mainly neurological. Although arterial complications are rare, they are potentially severe. Among these are aneurysms associated with embolism and thrombosis. The authors report a case of a 37 year-old woman with bilateral cervical rib that developed embolism in the right upper limb from a poststenotic right subclavian artery aneurysm and dilatation of the left subclavian artery, both due to compression