Investigating role of secretory antigens in altering activation of T cell signaling events in Jurkat T cells.

Background: Mycobacterium tuberculosis is able to survive and persist as an intracellular pathogen by modulating its own metabolism and host immunity. The molecules and mechanisms utilized to accomplish this modulation are not fully understood. The present study elucidates the effects of M.

Transcription factors STAT-4, STAT-6 and CREB regulate Th1/Th2 response in leprosy patients: effect of M. leprae antigens.

Background: Leprosy is an ideal human disease to study T cell regulation as patients show correlation between cytokine skewed Th1-Th2 responses and clinical forms of the disease. The Role of transcription factors on the modulation of Th1 and Th2 responses by M. leprae antigens has not been adequately studied.

Notch signaling induces lymphoproliferation, T helper cell activation and Th1/Th2 differentiation in leprosy.

The present study evaluates role of Notch1 signaling in the regulation of T cell immunity in leprosy. Peripheral blood mononuclear cells from leprosy patients and healthy controls were activated with Mycobacterium leprae antigens along with activation of Notch1 signaling pathway and then lymphoproliferation was analyzed by lymphocytes transformation test and the expression of Notch1 and its ligands DLL1, Jagged1 and Jagged 2, T cell activation marker and Th1-Th2 cytokines on Th cells in PBMCs of study subjects were analyzed by flow cytometry. Further, these parameters were also analyzed after inhibition of Notch1 signaling pathway.

Mycobacterium tuberculosis secretory proteins downregulate T cell activation by interfering with proximal and downstream T cell signalling events.

Background: Mycobacterium tuberculosis (M. tuberculosis) modulates host immune response, mainly T cell responses for its own survival leading to disease or latent infection. The molecules and mechanisms utilized to accomplish immune subversion by M.

Chemotherapeutic potential of curcumin-bearing microcells against hepatocellular carcinoma in model animals.

Curcumin (diferuloylmethane) is found in large quantities in the roots of Curcuma longa. It possesses strong antioxidant and anti-inflammatory properties, and inhibits chemically-induced carcinogenesis in the skin, forestomach, colon, and liver. Unfortunately, the poor bioavailability and hydrophobicity of curcumin pose a major hurdle to its use as a potent anticancer agent.

Phenolic-glycolipid-1 and lipoarabinomannan preferentially modulate TCR- and CD28-triggered proximal biochemical events, leading to T-cell unresponsiveness in mycobacterial diseases.

Background: Advanced stages of leprosy show T cell unresponsiveness and lipids of mycobacterial origin are speculated to modulate immune responses in these patients. Present study elucidates the role of phenolicglycolipid (PGL-1) and Mannose-capped lipoarabinomannan (Man-LAM) on TCR- and TCR/CD28- mediated signalling.

Results: We observed that lipid antigens significantly inhibit proximal early signalling events like Zap-70 phosphorylation and calcium mobilization.