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Effects of heme metabolism on HIV-1 latency reversal
Kompas, Maroš ; Mělková, Zora (advisor) ; Trejbalová, Kateřina (referee)
Progression of HIV infection in HIV-positive patients can now be successfully controlled by the combined antiretroviral therapy. However, due to persistence of the latent reservoir, HIV infection cannot be cured. The immune system nor current therapeutic approaches can target the pool of latently infected cells, thus strategies aiming at reactivation and subsequent elimination of the reservoir cells are recognized as possibly curative. This thesis has examined previously demonstrated latency-reversing capacity of heme arginate (HA), another redox modulator, and their synergism with Protein Kinase C inducer phorbol myristate acetate (PMA) to reactivate HIV-1 in the context of heme metabolism. HIV-1 reactivation was assessed by the intensity of green fluorescence in the model Jurkat cell line clone (A2), containing HIV-1 "mini-virus" (LTR-Tat-IRES-EFGP-LTR), as well as in the A2 cells stably transfected with plasmid vectors encoding cDNA for specific factors of heme metabolism and for control luciferase. While the administration of redox modulator alone did not stimulate expression from the HIV-1 LTR and HA reactivated the "mini-virus" only slightly, both compounds revealed a synergy with PMA in all cell lines studied. Basal and induced expression of EGFP was found variable in cells transfected with...
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Effects of heme arginate in HIV-1 acute infection and in latency reversal
Prakash, Shankaran ; Mělková, Zora (advisor) ; Hirsch, Ivan (referee) ; Hejnar, Jiří (referee)
The available antiretroviral compounds can effectively suppress the replication of HIV-1 and block the disease progression. However it is impossible to eradicate the virus from the organism as the HIV-1 integrated in the genome is not affected by the existing anti-HIV-1 drugs. Therefore, new latency reversing agents are being actively developed as part of "shock and kill" therapy to reactivate the provirus and clear the reservoir. Normosang (heme arginate; HA) is a human hemin- containing compound used to treat acute porphyria. Heme is physiologically catabolised by heme oxygenases to form iron (Fe2+ ), carbon monoxide (CO) and biliverdin that is further converted to bilirubin by biliverdin reductase. In this study, we have demonstrated that HA inhibited HIV-1 replication during the acute infection, which was accompanied by the inhibition of reverse transcription. On the other hand, HA synergised with phorbol myristyl acetate (PMA) and reactivated the HIV-1 provirus in ACH-2 cells and the HIV-1 "mini-virus" in Jurkat cell clones A2 and H12. HIV-1 ''mini-virus'' was reactivated also by HA-alone. Further, we have studied the effects of heme degradation products on latent HIV-1 reactivation when added individually. We employed addition of ascorbate to generate Fe2+ , resulting in an increased...
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Effects of heme arginate in HIV-1 acute infection and in latency reversal
Prakash, Shankaran ; Mělková, Zora (advisor) ; Hirsch, Ivan (referee) ; Hejnar, Jiří (referee)
The available antiretroviral compounds can effectively suppress the replication of HIV-1 and block the disease progression. However it is impossible to eradicate the virus from the organism as the HIV-1 integrated in the genome is not affected by the existing anti-HIV-1 drugs. Therefore, new latency reversing agents are being actively developed as part of "shock and kill" therapy to reactivate the provirus and clear the reservoir. Normosang (heme arginate; HA) is a human hemin- containing compound used to treat acute porphyria. Heme is physiologically catabolised by heme oxygenases to form iron (Fe2+ ), carbon monoxide (CO) and biliverdin that is further converted to bilirubin by biliverdin reductase. In this study, we have demonstrated that HA inhibited HIV-1 replication during the acute infection, which was accompanied by the inhibition of reverse transcription. On the other hand, HA synergised with phorbol myristyl acetate (PMA) and reactivated the HIV-1 provirus in ACH-2 cells and the HIV-1 "mini-virus" in Jurkat cell clones A2 and H12. HIV-1 ''mini-virus'' was reactivated also by HA-alone. Further, we have studied the effects of heme degradation products on latent HIV-1 reactivation when added individually. We employed addition of ascorbate to generate Fe2+ , resulting in an increased...
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