Premature skewing of T cell receptor clonality and delayed memory expansion in HIV-exposed infants
Ontology highlight
ABSTRACT: While preventing vertical HIV transmission has been very successful, HIV-exposed uninfected infants (iHEU) experience an elevated risk to infections compared to HIV-unexposed and uninfected infants (iHUU). Here we present a longitudinal multimodal analysis of infant immune ontogeny that highlights the impact of HIV/ARV exposure. Using mass cytometry, we show alterations in T cell memory differentiation between iHEU and iHUU being significant from week 15 of life. The altered memory T cell differentiation in iHEU was preceded by lower TCR Vβ clonotypic diversity and linked to TCR clonal depletion within the naïve T cell compartment. Compared to iHUU, iHEU had elevated CD56loCD16loPerforin+CD38+CD45RA+FcεRIγ+ NK cells at 1 month postpartum and whose abundance pre-vaccination were predictive of vaccine-induced pertussis and rotavirus antibody responses post 3 months of life. Collectively, HIV/ARV exposure disrupted the trajectory of innate and adaptive immunity from birth which may underlie relative vulnerability to infections in iHEU.
Project description:Increased morbidity and fetal growth restriction are reported in uninfected children born to human immunodeficiency virus type 1 (HIV-1)–infected women treated with antiretroviral (ARV) therapy. Viruses and/or pharmacological interventions such as ARVs can induce metabolic stress, skewing the cell’s immune response and restricting (cell) growth. Novel metabolomic techniques provided the opportunity to investigate the impact of fetal HIV-1 and combination ARV therapy (cART) exposure on the infants’ immune metabolome. Peroxidized lipids, generated by reactive oxygen species, were increased in cART/HIV-1–exposed infants, indicating altered mitochondrial functioning. The lipid metabolism was further dysregulated with increased triglyceride species and a subsequent decrease in phospholipids in cART/HIV-1–exposed infants compared to control infants. Proinflammatory immune mediators, lysophospholipids as well as cytokines such as CXCL10 and CCL3, were increased whereas anti-inflammatory metabolites from the cytochrome P450 pathway were reduced in cART/HIV-1–exposed infants. Taken together, these data demonstrate that the fetal metabolism is impacted by maternal factors (cART and HIV-1) and skews physiological immune responses toward inflammation in the newborn infant.
Project description:Background: Zidovudine remains the cornerstone drug for prophylaxis to prevent mother-to-child HIV-1 transmission. A mild but long-lasting hematological multilineage defect is observed in children exposed in utero. Objectives: To evaluate the effects of zidovudine-based ARV combinations on newborn cord blood cells. Methods: Cord blood-derived mononuclear cells from 22 HIV-1-uninfected newborn exposed in utero to a zidovudine-based ARV combination and from 20 healthy unexposed newborn were investigated by immunophenotyping, gene expression analysis, cytogenetic studies and functional capacity testing. To evaluate the effects of zidovudine-based ARV combinations on newborn cord blood cells.
Project description:Myeloid dendritic cells (mDC) were isolated from antiretroviral therapy (ARV)-treated and untreated people living with HIV (PLWH), and from HIV uninfected Individuals. The results indicate that mDC are altered in genes expression from PLWH. Some RNA transcriptional changes are not completely restored by ARV. This provides more data on myeloid cells, an understudied cell type, and alterations in PLWH.
Project description:Mechanisms by which HIV causes susceptibility to respiratory pathogens remain incompletely understood. We obtained whole blood and bronchoalveolar lavage (BAL) from people with latent TB infection in the presence or absence of ARV-naïve HIV co-infection. Transcriptomic and flow cytometric analyses demonstrated HIV-associated cell proliferation and type I interferon activity in blood and effector memory CD8 T-cells in BAL. Both compartments displayed reduced induction of CD8 T cell-related IL-17A in people with HIV, associated with elevated T cell regulatory molecule expression. We propose dysfunctional CD8 T cell responses in uncontrolled HIV contribute to susceptibility to secondary bacterial infections, including tuberculosis.
Project description:Mechanisms by which HIV causes susceptibility to respiratory pathogens remain incompletely understood. We obtained whole blood and bronchoalveolar lavage (BAL) from people with latent TB infection in the presence or absence of ARV-naïve HIV co-infection. Transcriptomic and flow cytometric analyses demonstrated HIV-associated cell proliferation and type I interferon activity in blood and effector memory CD8 T-cells in BAL. Both compartments displayed reduced induction of CD8 T cell-related IL-17A in people with HIV, associated with elevated T cell regulatory molecule expression. We propose dysfunctional CD8 T cell responses in uncontrolled HIV contribute to susceptibility to secondary bacterial infections, including tuberculosis.
Project description:Background: Zidovudine remains the cornerstone drug for prophylaxis to prevent mother-to-child HIV-1 transmission. A mild but long-lasting hematological multilineage defect is observed in children exposed in utero. Objectives: To evaluate the effects of zidovudine-based ARV combinations on newborn cord blood cells. Methods: Cord blood-derived mononuclear cells from 22 HIV-1-uninfected newborn exposed in utero to a zidovudine-based ARV combination and from 20 healthy unexposed newborn were investigated by immunophenotyping, gene expression analysis, cytogenetic studies and functional capacity testing.
Project description:HIV infection results in damage to the gastrointestinal (GI) tract, microbial translocation and immune activation, which are not completely ameliorated with suppression of viremia by antiretroviral (ARV) therapy. Furthermore, increased morbidity and mortality of ARV-treated HIV-infected individuals is associated with these dysfunctions. Thus, in order to enhance GI tract immunity, we treated SIV-infected pigtail macaques with ARVs supplemented with probiotics and prebiotics or with ARVs alone. In the colon, this synbiotic treatment resulted in increased expression of genes associated with antigen presenting cells (APCs), increased frequency and functionality of APCs, enhanced reconstitution and functionality of CD4+ T-cells and reduced fibrosis of lymphoid follicles. Thus, supplementing ARV treatment with synbiotic treatment in HIV-infected individuals may improve GI tract immunity and thereby mitigate inflammatory sequelae, ultimately improving prognosis. CD45+ (clone MB4-6D6) leukocytes were sorted from thawed colon samples from 4 ARV + probiotics animals and 4 ARV alone animals
Project description:In this work, we investigated the frequency and oligoclonal expansion of effector CD28-CD57+ memory cells in CD8+ T cell compartments and the T-cell Receptor (TCR) Vβ repertoire in acquired aplastic anemia (AA) to provide additional evidence to the immune hypothesis in AA pathophysiology. Using flow cytometry, deep sequencing, and computational methods, we examined the blood of 32 AA patients and 29 appropriate controls for Vβ usage; eight of these patients showing CD8+CD57+ expansion and three healthy subjects were subjected to TCR deep sequencing to confirm the clonality. We showed that CD8+CD57+ cells were frequently expanded with oligoclonal characteristics in AA, and patients and healthy donors shared CD8+ clonotypes by complementarity-determining region 3 sequences analysis.
Project description:In perinatal HIV infection, early ART initiation is recommended but questions remain regarding infant immune responses to HIV and impact of HIV on immune development. Using single cell transcriptional and phenotypic analysis we evaluated the T cell compartment at pre-ART initiation of infants with perinatally acquired HIV from Maputo, Mozambique (TARA cohort). CD8+ T cell maturation subsets exhibited altered distribution in HIV exposed infected (HEI) infants relative to control infants (HIV exposed uninfected) with reduced naïve, increased effectors, higher frequencies of activated T cells, and lower frequencies of cells with markers of self-renewal. Additionally, a cluster of CD8+ T cells identified in HEI displayed gene profiles consistent with cytotoxic T lymphocytes (CTL) and showed evidence for hyper expansion. Longitudinal phenotypic analysis revealed accelerated maturation of CD8+ T cells was maintained in HEI despite viral control. The results point to a HIV directed immune response that is likely to influence reservoir establishment.
Project description:Recently, several neutralizing anti-HIV antibodies have been isolated from memory B cells of HIV-infected individuals. However, despite extensive evidence of B-cell dysfunction in HIV disease, little is known about the cells from which these rare HIV-specific antibodies originate. Accordingly, HIV envelope gp140 and CD4 or co-receptor (CoR) binding site (bs) mutant probes were used to evaluate HIV-specific responses in the peripheral blood B cells of individuals at various stages of infection. In contrast to non-HIV responses, HIV-specific responses against gp140 were enriched within abnormal B cells, namely activated and exhausted memory subsets, which are largely absent in the blood of uninfected individuals. Responses against the CoRbs (a poorly-neutralizing epitope) arose early whereas those against the CD4bs (a well-characterized neutralizing epitope) were delayed and infrequent. Enrichment of the HIV-specific response within resting memory B cells, the predominant subset in uninfected individuals, did occur in certain infected individuals who maintained low levels of plasma viremia and immune activation with or without antiretroviral therapy. These findings were corroborated by transcriptional profiles. Taken together, our findings provide valuable insight into virus-specific B-cell responses in HIV infection and demonstrate that memory B-cell abnormalities may contribute to the ineffectiveness of the antibody response in infected individuals. HIV-specific responses against gp140 were enriched within abnormal B cells, namely activated (AM) and exhausted (tissue-like; TLM) memory subsets, which are largely absent in the blood of uninfected individuals. These responses are highest during the early stage of HIV infection, significantly decreased following the initiation of antiretroviral therapy (ART), and most importantly, enriched in normal resting memory B cells (RM) when HIV viremia and immune activation are controlled either naturally or as a result of ART. These HIV-specific B cells (AM and TLM) and resting memory B cells (RM) were sorted from peripheral blood mononuclear cells (PBMCs) of 6 HIV infected individuals. In addition, gp140-specific IgG+ B cells were sorted from individuals with either a strong (n= 6) or weak (n= 6) pro-resting memory profile. TaqMan gene expression assay was performed on these HIV-specific B cells and B cell subset. The array consisted of 29 genes.