1,721,036 research outputs found
Anti-beta2 glycoprotein I antibodies prevent the De-activation of platelets and sustain their phagocytic clearance.
The immunogenicity of experimental tumors is strongly biased by the expression of dominant viral cytotoxic T-lymphocyte epitopes
The immunogenic Friend-Moloney-Rauscher (FMR) virus-induced tumors have been used extensively to clarify the cellular and molecular mechanisms responsible for tumor rejection and to develop immunotherapeutic strategies. We characterize here the trimolecular complex MHC class I-antigenic determinant-T cell receptor involved in the induction of a protective CTL response against the RMA thymoma. This complex is mainly composed by the D(b) molecule interacting with a Rauscher virus antigen (Ag) determinant and the Vbeta5+ T cell receptor. We also show that the chemically induced EL-4 thymoma acquires the susceptibility to recognition by anti-RMA CTLs and the ability to elicit a protective anti-RMA CTL response only upon infection by a virus of the FMR family and that RMA and FMR virus infected EL-4 cells share tumor-associated Ag. The data strongly support the hypothesis that the high immunogenicity of virus-induced or infected tumors is determined by the expression of immunodominant virus-encoded Ag. The demonstration of a different outcome in the immune responses elicited in the presence or in the absence of viral Ag further open the contention of the molecular requirements for immunogenicity and should stimulate a more careful revision of unexpected cross-reactivity among tumors
Immunohistochemical evidence of a cytokine and chemokine network in three patients with Erdheim-Chester disease: Implications for pathogenesis.
OBJECTIVE:
Erdheim-Chester disease (ECD) is a rare form of non-Langerhans' cell histiocytosis (LCH) of unknown etiology, characterized by diffuse histiocyte infiltration of bones and soft tissue. The purpose of this study was to assess cell proliferation and expression of cytokines, chemokines, and chemokine receptors that may potentially be important in histiocyte accumulation in ECD lesions.
METHODS:
Biopsies were performed on 3 patients with ECD. The diagnosis of the disease was based on clinical signs including typical radiologic osteosclerosis, and on the detection of foamy CD68+,CD1a- non-Langerhans' cell histiocytes on histologic examination. The expression of the proliferation marker Ki-67 as well as of selected chemokine/chemokine receptor pairs and cytokines was analyzed by immunohistochemistry.
RESULTS:
In all samples, Ki-67 was undetectable in CD68+ histiocytes. Conversely, these cells expressed the chemokines CCL2 (monocyte chemotactic protein 1), CCL4/macrophage inflammatory protein 1beta (MIP-1beta), CCL5/RANTES, CCL20/MIP-3alpha, and CCL19/MIP-3beta, and their counter-receptors CCR1, CCR2, CCR3, CCR5, CCR6, and CCR7. Moreover, ECD histiocytes expressed interferon-gamma-inducible 10-kd protein (CXCL10), which is specifically induced by interferon-gamma, and interleukin-6 and RANKL, which are both implicated in bone remodeling. Finally, all cases showed a Th1-type lymphocyte infiltrate.
CONCLUSION:
Our data indicate that, similar to LCH, ECD lesions are characterized by a complex cytokine and chemokine network, which may orchestrate histiocyte activation and accumulation through an autocrine loop and contribute to the pathogenesis of the disease
In vivo tests with "Tahini" sauce: new allergenic source to evaluate IgE-mediated hypersensitivity to sesame.
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