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Type I IFNs (TI-IFNs) drive immune effector functions during acute viral infections and regulate cell cycling and systemic metabolism. That said, chronic TI-IFN signaling in the context of HIV infection treated with antiretroviral therapy (ART) also facilitates viral persistence, in part by promoting immunosuppressive responses and CD8+ T cell exhaustion. To determine whether inhibition of IFN-α might provide benefit in the setting of chronic, ART-treated SIV infection of rhesus macaques, we administered an anti-IFN-α antibody followed by an analytical treatment interruption (ATI). IFN-α blockade was well-tolerated and associated with lower expression of TI-IFN-inducible genes (including those that are antiviral) and reduced tissue viral DNA (vDNA). The reduction in vDNA was further accompanied by higher innate proinflammatory plasma cytokines, expression of monocyte activation genes, IL-12-induced effector CD8+ T cell genes, increased heme/metabolic activity, and lower plasma TGF-β levels. Upon ATI, SIV-infected, ART-suppressed nonhuman primates treated with anti-IFN-α displayed lower levels of weight loss and improved erythroid function relative to untreated controls. Overall, these data demonstrated that IFN-α blockade during ART-treated SIV infection was safe and associated with the induction of immune/erythroid pathways that reduced viral persistence during ART while mitigating the weight loss and anemia that typically ensue after ART interruption.

Gut microbes can profoundly modulate mucosal barrier-promoting Th17 cells in mammals. A salient feature of HIV/simian immunodeficiency virus (SIV) immunopathogenesis is the loss of Th17 cells, which has been linked to increased activity of the immunomodulatory enzyme, indoleamine 2,3-dioxygenase 1 (IDO 1). The role of gut microbes in this system remains unknown, and the SIV-infected rhesus macaque provides a well-described model for HIV-associated Th17 loss and mucosal immune disruption. We observed a specific depletion of gut-resident Lactobacillus during acute and chronic SIV infection of rhesus macaques, which was also seen in early HIV-infected humans. This depletion in rhesus macaques correlated with increased IDO1 activity and Th17 loss. Macaques supplemented with a Lactobacillus-containing probiotic exhibited decreased IDO1 activity during chronic SIV infection. We propose that Lactobacillus species inhibit mammalian IDO1 and thus may help to preserve Th17 cells during pathogenic SIV infection, providing support for Lactobacillus species as modulators of mucosal immune homeostasis.

ObjectiveMicrobial translocation and innate immune action characterize HIV infection. Continued gut mucosal dysfunction during treatment and its relationship to CD4 T-cell recovery has not been well described.DesignA cross-sectional study was performed of antiretroviral therapy (ART)-suppressed (immunologic responders with CD4 > 500 cells/μl and immunologic nonresponders with CD4

The anti-inflammatory agent, mesalamine (5-aminosalicylic acid) has been shown to decrease mucosal inflammation in ulcerative colitis. The effect of mesalamine in HIV-infected individuals, who exhibit abnormal mucosal immune activation and microbial translocation (MT), has not been established in a placebo-controlled trial. We randomized 33 HIV-infected subjects with CD4 counts

ObjectivePersistent systemic inflammation is associated with the inability of some HIV-infected patients to normalize circulating CD4 T-cell levels after years of suppressive antiretroviral therapy. In this study, we sought to understand whether such systemic inflammation is also associated with detectable signs of inflammation in biopsies from the rectosigmoid colon.DesignImmunologic and virological parameters were studied in the peripheral blood and in rectosigmoid colon biopsies from individuals with viral suppression for at least 2 years and with peripheral CD4 T-cell levels of 500 cells per cubic millimeter (immunologic responders, n = 16).MethodsPeripheral blood and rectosigmoid colon biopsies were analyzed by flow cytometry, enzyme-linked immunosorbent assay, and quantitative polymerase chain reaction.ResultsNonresponders had elevated T-cell activation and inflammatory cytokines in the circulation, but inflammatory gene expression in colon biopsies was not different as compared with responders, and there was little relationship between blood and colon markers of inflammation. Blood inflammatory markers were positively associated with soluble CD14 levels indicative of monocyte activation.ConclusionsThese findings demonstrate that, in the context of treated HIV disease, it is easier to detect parameters of inflammation (including blood monocyte activation) in the peripheral blood than in isolated rectosigmoid colon biopsies. Accordingly, interventions to block such inflammation in this population might be most conveniently and accurately assessed in blood.

Latency reveRsaI strategies for HIV cure using inhibitor of apoptosis protein (IAP) antagonists (IAPi) induce unprecedented levels of latent reservoir expression without immunotoxicity during suppressive antiretroviral therapy (ART). However, full targeting of the reservoir may require combinatorial approaches. A Jurkat latency model screen for IAPi combination partners demonstrated synergistic latency reveRsaI with bromodomain (BD) and extraterminal domain protein inhibitors (BETi). Mechanistic investigations using CRISPR-CAS9 and single-cell RNA-Seq informed comprehensive ex vivo evaluations of IAPi plus pan-BET, bD-selective BET, or selective BET isoform targeting in [CD4.sup.+] T cells from ART-suppressed donors. IAPi+BETi treatment resulted in striking induction of cell-associated HIV gag RNA, but lesser induction of fully elongated and tat-rev RNA compared with T cell activation-positive controls. IAPi+BETi resulted in HIV protein induction in bulk cultures of [CD4.sup.+] T cells using an ultrasensitive p24 assay, but did not result in enhanced viral outgrowth frequency using a standard quantitative viral outgrowth assay. This study defines HIV transcriptional elongation and splicing as important barriers to latent HIV protein expression following latency reveRsaI, delineates the roles of BET proteins and their BDs in HIV latency, and provides a rationale for exploration of IAPi+BETi in animal models of HIV latency., Introduction HIV cure remains elusive because of latent but replication-competent HIV DNA within host [CD4.sup.+] T cells during long-term suppressive antiretroviral therapy (ART) (1, 2). HIV latency is maintained by [...]

Progressive HIV infection is characterized by dysregulation of the intestinal immune barrier, translocation of immunostimulatory microbial products, and chronic systemic inflammation that is thought to drive progression of disease to AIDS. Elements of this pathologic process persist despite viral suppression during highly active antiretroviral therapy (HAART), and drivers of these phenomena remain poorly understood. Disrupted intestinal immunity can precipitate dysbiosis that induces chronic inflammation in the mucosa and periphery of mice. However, putative microbial drivers of HIV-associated immunopathology versus recovery have not been identified in humans. Using high-resolution bacterial community profiling, we identified a dysbiotic mucosal-adherent community enriched in Proteobacteria and depleted of Bacteroidia members that was associated with markers of mucosal immune disruption, T cell activation, and chronic inflammation in HIV-infected subjects. Furthermore, this dysbiosis was evident among HIV-infected subjects undergoing HAART, and the extent of dysbiosis correlated with activity of the kynurenine pathway of tryptophan catabolism and plasma concentrations of the inflammatory cytokine interleukin-6 (IL-6), two established markers of disease progression. Gut-resident bacteria with capacity to catabolize tryptophan through the kynurenine pathway were found to be enriched in HIV-infected subjects, strongly correlated with kynurenine levels in HIV-infected subjects, and capable of kynurenine production in vitro. These observations demonstrate a link between mucosal-adherent colonic bacteria and immunopathogenesis during progressive HIV infection that is apparent even in the setting of viral suppression during HAART. This link suggests that gut-resident microbial populations may influence intestinal homeostasis during HIV disease.

Even in the setting of maximally suppressive antiretroviral therapy (ART), HIV persists indefinitely. Several mechanisms might contribute to this persistence, including chronic inflammation and immune dysfunction. In this study, we have explored a preclinical model for the evaluation of potential interventions that might serve to eradicate or to minimize the level of persistent virus. Given data that metabolic products of the inducible enzyme indoleamine 2,3-dioxygeanse (IDO) might foster inflammation and viral persistence, chronically simian immunodeficiency virus (SIV)-infected, ART-treated rhesus macaques were treated with the IDO inhibitor 1-methyl tryptophan (1mT). Orally administered 1mT achieved targeted plasma levels, but did not impact tryptophan metabolism or decrease viral RNA or DNA in plasma or in intestinal tissues beyond levels achieved by ART alone. Animals treated with 1mT showed no difference in the levels of T cell activation or differentiation, or in the kinetics or magnitude of viral rebound following cessation of ART. Notwithstanding these negative results, our observations suggest that the chronically SIV-infected rhesus macaque on suppressive ART can serve as a tractable model in which to test and to prioritize the selection of other potential interventions designed to eradicate HIV in vivo. In addition, this model might be used to optimize the route and dose by which such interventions are administered and the methods by which their effects are monitored.

Mathematical formulae were devised for the purpose of generating continuous measures of the four identity statuses from measures of exploration and commitment. The formulae were consistent with the conceptual definitions of the statuses. They were found to be effective both in terms of generating continuous measures of the statuses and in terms of deriving status assignments. (Author)

Examines gender differences in domain-specific areas of identity development among college youth (N=210). Also explores gender comparisons of relationships among domains. Results indicate that males were more likely to explore and commit in politics, whereas females were more likely to explore in sex roles and to commit in religion and dating. (RJM)

Adaptive T cell responses are critical for controlling infections with viruses such as HIV, HBV, and HCV. However, these responses must be carefully regulated because overly vigorous T cell activation can lead to excessive host tissue damage. T cell expression of the inhibitory receptor programmed death-1 (PD-1) and inhibition of effector T cells (Teffs) by [CD4.sup.+][Foxp3.sup.+] Tregs are among the many described mechanisms for achieving a balanced immune response. Although the signals that contribute to Teff function are well understood, less is known about the signals controlling Tregs. In this issue of the JCI, Franceschini et al. extend our understanding of how Tregs are modulated during chronic HCV infection by demonstrating that Treg proliferation is inhibited by PD-1 and that this inhibition is mediated by a potentially novel mechanism involving the prevention of IL-2-driven STAT-5 phosphorylation (see the related article beginning on page 551)., Tregs represent a subset of [CD4.sup.+] T cells that can inhibit the proliferation and/or cytokine production of responding effector T cells (Teffs). There are many proposed mechanisms by which this [...]

Naturally SIV-infected sooty mangabeys (SMs) remain asymptomatic despite high virus replication. Elucidating the mechanisms underlying AIDS resistance of SIV-infected SMs may provide crucial information to better understand AIDS pathogenesis. In this study, we assessed the determinants of set-point viremia in naturally SIV-infected SMs, i.e., immune control of SIV replication versus target cell limitation. We depleted [CD4.sup.+] T cells in 6 naturally SIV-infected SMs by treating with humanized anti-CD4 mAb (Cdr-OKT4A-huIgG1). [CD4.sup.+] T cells were depleted almost completely in blood and BM and at variable levels in mucosal tissues and LNs. No marked depletion of [CD14.sup.+] monocytes was observed. Importantly, [CD4.sup.+] T cell depletion was associated with a rapid, significant decline in viral load, which returned to baseline level at day 30-45, coincident with an increased fraction of proliferating and activated [CD4.sup.+] T cells. Throughout the study, virus replication correlated with the level of proliferating [CD4.sup.+] T cells. [CD4.sup.+] T cell depletion did not induce any changes in the fraction of Tregs or the level of SIV-specific [CD8.sup.+] T cells. Our results suggest that the availability of activated [CD4.sup.+] T cells, rather than immune control of SIV replication, is the main determinant of set-point viral load during natural SIV infection of SMs., Introduction The HIV epidemic in humans arose after zoonotic transmission of simian [CD4.sup.+] T cell tropic lentiviruses, which naturally infect a range of African monkey host species and are now [...]

This research investigated Erikson's theory that adolescent identity exploration is associated with a variety of symptoms, such as fluctuations in ego strength, mood swings, rebelliousness, and heightened physical complaints. A sample of 82 high school students completed the Minnesota Multiphasic Personality Inventory (MMPI) and the Ego-Identity Interview. Identity exploration was correlated with 23 major clinical scales and the 14 Frequently Scored Scales of the MMPI. A factor analysis revealed seven scales loading on a single factor, which accounted for 39% of the variance in exploration. The items in the factor suggested a pattern consistent with Erikson's theory of adolescent crisis, and was labeled the Identity Exploration Crisis (IEC) factor. Adolescents who were actively engaged in identity exploration were more likely to produce a personality pattern characterized by self-doubt, confusion, disturbed thinking, impulsivity, conflicts with parents and other authority figures, reduced ego strength, and increased physical symptoms., According to Erikson, exploration is at the heart of the adolescent transition. In his words, exploration is the identity crisis, although crises are not necessarily acute or severe (Erikson, 1959). [...]