A new antiviral: chimeric 3TC-AZT phosphonate efficiently inhibits HIV-1 in human tissues ex vivo

Dual-targeted anti-CMV/anti-HIV-1 heterodimers

Despite the development of efficient anti-human immunodeficiency virus-1 (HIV-1) therapy, HIV-1 associated pathogens remain a major clinical problem. Human cytomegalovirus (CMV) is among the most common HIV-1 copathogens and one of the main causes of persistent immune activation associated with dysregulation of the immune system, cerebrovascular and cardiovascular pathologies, and premature aging. Here, we report on the development of dual-targeted drugs with activity against both HIV-1 and CMV. We synthesized seven compounds that constitute conjugates of molecules that suppress both pathogens. We showed that all seven compounds exhibit low cytotoxicity and efficiently inhibited both viruses in cell lines. Furthermore, we chose a representative compound and demonstrated that it efficiently suppressed replication of HIV-1 and CMV in human lymphoid tissue ex vivo coinfected with both viruses. Further development of such compounds may lead to the development of dual-targeted anti-CMV/HIV-1 drugs.

Histoculture and Infection with HIV of Functional Human Lymphoid Tissue on Gelfoam®

Gelfoam^® histoculture provides a valuable tool for experimental studies of normal and pathological tissue physiology. It allows us to understand cell-cell interactions by mirroring their original spatial relationship within body tissues. Gelfoam^® histoculture can be employed to model host-pathogen interactions mimicking in vivo conditions in vitro. In the present chapter, we describe a protocol to process and infect lymphoid tissue explants with HIV and maintain them in Gelfoam^® histoculture at the liquid-air interface. The Gelfoam^® histocultures with human immunodeficiency virus (HIV) type 1-infected tissues have been used to further understand the biology of early HIV-1 pathogenesis, as well as a novel ex vivo platform to test the efficacy and toxicity of antiviral drugs.

Dual-targeted anti-TB/anti-HIV heterodimers

HIV and M. tuberculosis are two intersecting epidemics making the search for new dual action drugs against both pathogens extremely important. Here, we report on the synthesis and suppressive activities of five dual-targeted HIV/TB compounds. These compounds are heterodimers of AZT, as anti-HIV molecules, and 5-substituted uracil derivatives, as anti-TB molecules. We found that these compounds inhibit the growth of M. tuberculosis and suppress the replication of HIV in human cell cultures and human lymphoid tissues ex vivo. We identified one particular heterodimer that inhibited both HIV and the drug-resistant TB strain MS-115 most potently. This compound demonstrated low toxicity and had no cytostatic effect on cells in culture, constituting an ideal candidate for future development and further in vivo testing.

A common anti-cytomegalovirus drug, ganciclovir, inhibits HIV-1 replication in human tissues ex vivo

BACKGROUND

Cytomegalovirus (CMV) is a common HIV-1 copathogen. Since CMV infection is an important contributor to immune activation, the driving force of HIV disease, an anti-CMV strategy might be beneficial to HIV-infected patients. Shin et al. (J Acquir Immune Defic Syndr 2014; 65:251-258) reported that anti-CMV therapy with valganciclovir in coinfected individuals results in a decrease of HIV viral load that is not accompanied by a decrease of immune activation. This suggests an alternative mechanism for HIV inhibition other than suppression of CMV-mediated inflammation.

METHOD

We evaluated the anti-HIV activity of ganciclovir (GCV), the active form of valganciclovir, on HIV replication in human tissues ex vivo.

RESULTS

We show that GCV has a direct suppressive activity on HIV replication in human tissues ex vivo, including laboratory strains, drug-resistant and primate HIV-1 isolates. We deciphered the mechanism of this inhibition and showed that GCV-TP is incorporated in the nascent DNA chain and acts as a delayed chain terminator.

CONCLUSION

Our results suggest that anti-CMV strategy using valganciclovir in HIV-1-infected individuals may reduce HIV-1 viral load not only indirectly by decreasing CMV-mediated immune activation but also directly by inhibiting HIV-1 reverse transcriptase.