ABSTRACT
Adeno-associated virus (AAV)-based gene therapies are emerging strategies in Duchenne muscular dystrophy (DMD) treatment. Exposure to wild-type AAV can lead to development of neutralizing antibodies (NAbs) and blocking of AAV transduction, thereby limiting the delivery of AAV vector-based gene therapy. Therefore, it is imperative to check for the presence of AAV NAbs in a patient who is a candidate for gene therapy. We prospectively enrolled 101 genetically confirmed males with DMD (median age 11 years, 48% ambulatory and 59% on steroids) and performed AAV neutralization assays against AAV2, AAV8, AAV9, and AAVrh74 serotypes. The serotype analysis showed that AAV9 (36%) and AAVrh74 (32%) seroprevalence was lower compared with AAV2 (56%) and AAV8 (47%). Interestingly, age was not correlated with NAb titer for any of the capsids. NAb responses were observed at a higher frequency in African American participants and at a lower frequency in Caucasian participants for all four serotypes. Further analysis showed no significant differences in NAb titers regardless of serotype and whether participants were taking steroids or not. Finally, we observed higher AAV8, AAV9, and AAVrh74 seroprevalence and significantly higher AAV2 and AAV8 NAb titers in participants who were ambulatory compared with nonambulatory participants. Overall, these data identify AAV9 and AAVrh74 as the two serotypes with lower pre-existing NAb titers in this study's cohort of 101 males with DMD, possibly showing their utility in future gene therapy applications in treatment of this cohort of patients with DMD.
Subject(s)
Antibodies, Neutralizing , Muscular Dystrophy, Duchenne , Male , Humans , Child , Antibodies, Viral , Dependovirus/genetics , Seroepidemiologic Studies , Genetic VectorsABSTRACT
Antiretroviral therapy has slowed the HIV/AIDS pandemic and is currently being used as a prophylactic measure for individuals at high risk of infection. However, concerns over adverse effects of long-term use need to be explored. We hypothesize that this may occur, at least in part, through off-target effects via select steroid receptors (SRs) that broadly regulate multiple physiological processes. We investigated the effects of maraviroc (MVC), tenofovir disoproxil fumarate (TDF), and dapivirine (DPV) on progesterone receptor B (PR-B) transcriptional activity. We found that MVC and TDF activate PR-B transcription in the absence of progestogens on a PR-regulated promoter reporter construct and on endogenous PR-regulated genes. MVC and TDF exhibited no direct binding to PR-B; however, increased PR-B phosphorylation was detected with TDF but not MVC. DPV transactivated gilz and ptgs2 in the absence of progestogens and exhibited PR-B binding while showing no effects on phosphorylation, suggesting that it may activate PR-B through a direct mechanism. Our study shows that potential off-target immunomodulatory effects of MVC, TDF and DPV occur in vitro and these are most likely mediated by different mechanisms of PR-B activation.
Subject(s)
Anti-HIV Agents/adverse effects , Maraviroc/adverse effects , Pyrimidines/adverse effects , Receptors, Progesterone/agonists , Tenofovir/adverse effects , Anti-HIV Agents/pharmacokinetics , Binding, Competitive , Cell Line , Contraceptive Agents, Hormonal/pharmacokinetics , Contraceptive Agents, Hormonal/pharmacology , HIV Infections/drug therapy , HIV-1 , Humans , Immunologic Factors/adverse effects , In Vitro Techniques , Levonorgestrel/pharmacokinetics , Levonorgestrel/pharmacology , Maraviroc/pharmacokinetics , Phosphorylation , Progesterone Congeners/pharmacokinetics , Progesterone Congeners/pharmacology , Pyrimidines/pharmacokinetics , Receptors, Progesterone/genetics , Receptors, Progesterone/metabolism , Tenofovir/pharmacokinetics , Transcriptional Activation/drug effectsABSTRACT
Millions of women are exposed simultaneously to antiretroviral drugs (ARVs) and progestin-based hormonal contraceptives. Yet the reciprocal modulation by ARVs and progestins of their intracellular functions is relatively unexplored. We investigated the effects of tenofovir disoproxil fumarate (TDF) and dapivirine (DPV), alone and in the presence of select steroids and progestins, on cell viability, steroid-regulated immunomodulatory gene expression, activation of steroid receptors, and anti-HIV-1 activity in vitro Both TDF and DPV modulated the transcriptional efficacy of a glucocorticoid agonist via the glucocorticoid receptor (GR) in the U2OS cell line. In TZM-bl cells, DPV induced the expression of the proinflammatory interleukin 8 (IL-8) gene while TDF significantly increased medroxyprogesterone acetate (MPA)-induced expression of the anti-inflammatory glucocorticoid-induced leucine zipper (GILZ) gene. However, peripheral blood mononuclear cell (PBMC) and ectocervical explant tissue viability and gene expression results, along with TZM-bl HIV-1 infection data, are reassuring and suggest that TDF and DPV, in combination with dexamethasone (DEX) or MPA, do not reciprocally modulate key biological effects in primary cells and tissue. We show for the first time that TDF induces progestogen-independent activation of the progesterone receptor (PR) in a cell line. The ability of TDF and DPV to influence GR and PR activity suggests that their use may be associated with steroid receptor-mediated off-target effects. This, together with cell line and individual donor gene expression responses in the primary models, raises concerns that reciprocal modulation may cause side effects in a cell- and donor-specific manner in vivo.
