http://192.168.1.40:8080/xmlui/handle/123456789/1060 Sun, 31 May 2026 13:43:09 GMT 2026-05-31T13:43:09Z http://192.168.1.40:80/xmlui/bitstream/id/62c4b555-ca31-41dd-9312-097f6fbae1bf/manikuntala.jpg http://192.168.1.40:8080/xmlui/handle/123456789/1060 http://192.168.1.40:8080/xmlui/handle/123456789/2438 Fas-, caspase 8-, and caspase 3-dependent signaling regulates the activity of the aminophospholipid translocase and phosphatidylserine externalization in human erythrocytes Mandal, Debabrata; Mazumder, A.; Das, P.; Kundu, Manikuntala; Basu, Joyoti Apoptosis and erythrocyte senescence share the common feature of exposure of phosphatidylserine ( PS) in the outer leaflet of the cells. Western analysis showed that mature red cells contain Fas, FasL, Fas-associated death domain ( FADD), caspase 8, and caspase 3. Circulating, aged cells showed colocalization of Fas with the raft marker proteins G alpha(s) and CD59; the existence of Fas-associated FasL, FADD and caspase 8; and caspase 8 and caspase 3 activity. Aged red cells had significantly lower aminophospholipid translocase activity and higher levels of PS externalization in comparison with young cells. In support of our contention that caspases play a functional role in the mature red cell, the oxidatively stressed red cell recapitulated apoptotic events, including translocation of Fas into rafts, formation of a Fas-associated complex, and activation of caspases 8 and 3. These events were independent of calpain but dependent on reactive oxygen species ( ROS) as evident from the effects of the ROS scavenger N-acetylcysteine. Caspase activation was associated with loss of aminophospholipid translocase activity and with PS externalization. ROS was not generated by treatment of cells with t-butyl hydroperoxide at 10 degrees C, and Fas did not translocate into rafts. Concomitantly, neither formation of a Fas-associated signaling complex nor caspase activation could be observed, supporting the view that translocation of Fas into rafts was the trigger for the chain of events leading to caspase 3 activation. Our data demonstrate for the first time the novel involvement of Fas/caspase 8/caspase 3-dependent signaling in an enucleated cell leading to PS externalization, a central feature of erythrophagocytosis and erythrocyte biology. DOI: 10.1074/jbc.M506928200 Fri, 25 Nov 2005 00:00:00 GMT http://192.168.1.40:8080/xmlui/handle/123456789/2438 2005-11-25T00:00:00Z http://192.168.1.40:8080/xmlui/handle/123456789/2436 Mycobacterium tuberculosis lipoarabinomannan-mediated IRAK-M induction negatively regulates toll-like receptor-dependent interleukin-12 p40 production in macrophages Pathak, Sushil Kumar; Basu, Sandip Kumar; Bhattacharyya, Asima K.; Pathak, Shresh; Kundu, Manikuntala; Basu, Joyoti Mannose-capped lipoarabinomannans (Man-LAMs) are members of the repertoire of Mycobacterium tuberculosis modulins that the bacillus uses to subvert the host innate immune response. Interleukin-12 (IL-12) production is critical for mounting an effective immune response by the host against M. tuberculosis. We demonstrate that Man-LAM inhibits IL-12 p40 production mediated by subsequent challenge with lipopolysaccharide (LPS). Man-LAM inhibits LPS-induced IL-12 p40 expression in an IL-10-independent manner. It attenuates LPS-induced NF-kappa B-driven luciferase gene expression, suggesting that its effects are likely directly related to inhibition of NF-kappa B. This is probably because of dampening of the Toll-like receptor signaling. Man-LAM inhibits IL-1 receptor-associated kinase (IRAK)-TRAF6 interaction as well as I kappa B-alpha phosphorylation. It directly attenuates nuclear translocation and DNA binding of c-Rel and p50. Man-LAM exerts these effects by inducing the expression of Irak-M, a negative regulator of TLR signaling. Knockdown of Irak-M expression by RNA interference reinstates LPS-induced IL-12 production in Man-LAM-pretreated cells. The fact that Irak-M expression could be elicited by yeast mannan suggested that ligation of the mannose receptor by the mannooligosaccharide caps of LAM was the probable trigger for IRAK-M induction. DOI: 10.1074/jbc.M506471200 Fri, 30 Dec 2005 00:00:00 GMT http://192.168.1.40:8080/xmlui/handle/123456789/2436 2005-12-30T00:00:00Z http://192.168.1.40:8080/xmlui/handle/123456789/2433 The serine/threonine kinase PknB of Mycobacterium tuberculosis phosphorylates PBPA, a penicillin-binding protein required for cell division Dasgupta, Arunava; Datta, Pratik; Kundu, Manikuntala; Basu, Joyoti ANR-2005-06 DOI: 10.1099/mic.0.28630-0 Wed, 01 Feb 2006 00:00:00 GMT http://192.168.1.40:8080/xmlui/handle/123456789/2433 2006-02-01T00:00:00Z http://192.168.1.40:8080/xmlui/handle/123456789/2251 IL-32: An emerging player in the immune response network against tuberculosis? Kundu, Manikuntala; Basu, Joyoti [No abstract available] DOI: 10.1371/journal.pmed.0030274 Tue, 01 Aug 2006 00:00:00 GMT http://192.168.1.40:8080/xmlui/handle/123456789/2251 2006-08-01T00:00:00Z