Project description:Failures to produce neutralizing antibodies upon HIV-1 infection result in part from B cell dysfunction due to unspecific B cell activation. How HIV-1 affects antigen-specific B cell functions remains elusive. Using an adoptive transfer mouse model and ex vivo HIV infection of human tonsil tissue we found that expression of the HIV-1 pathogenesis factor NEF in CD4 T cells undermines their helper function and impairs cognate B cell functions including mounting of efficient specific IgG responses. NEF interfered with T cell help via a specific protein interaction motif that prevents polarized cytokine secretion at the T cell - B cell immune synapse. This interference reduced B cell activation and proliferation and thus disrupted germinal center formation and affinity maturation. These results identify NEF as a key component for HIV-mediated dysfunction of antigen-specific B cells. Therapeutic targeting of the identified molecular surface in NEF will facilitate host control of HIV infection. We used microarray analysis to understand
Project description:BACKGROUND: Combination antiretroviral therapy (cART) is able to control HIV-1 viral replication, however long-lived latent infection in resting memory CD4+ T-cells persist. The mechanisms for establishment and maintenance of latent infection in resting memory CD4+ T-cells remain unclear. Previously we have shown that HIV-1 infection of resting CD4+ T-cells co-cultured with CD11c+ myeloid dendritic cells (mDC) produced a population of non-proliferating T-cells with latent infection. Here we asked whether different antigen presenting cells (APC), including subpopulations of DC and monocytes, were able to induce post-integration latent infection in resting CD4+ T-cells, and examined potential cell interactions that may be involved using RNA-seq. RESULTS: mDC (CD1c+), SLAN+ DC and CD14+ monocytes were most efficient in stimulating proliferation of CD4+ T-cells during syngeneic culture and in generating post-integration latent infection in non-proliferating CD4+ T-cells following HIV-1 infection of APC-T-cell co-cultures. In comparison, plasmacytoid DC (pDC) and B-cells did not induce latent infection in APC-T-cell co-cultures. We compared the RNA expression profiles of APC subpopulations that could and could not induce latency in non-proliferating CD4+ T-cells. Gene expression analysis, comparing the mDC, SLAN+ DC and CD14+ monocyte subpopulations to pDC identified 53 upregulated genes that encode proteins expressed on the plasma membrane that could signal to CD4+ T-cells via cell-cell interactions (32 genes), immune checkpoints (IC) (5 genes), T-cell activation (9 genes), regulation of apoptosis (5 genes), antigen presentation (1 gene) and through unknown ligands (1 gene). CONCLUSIONS: APC subpopulations from the myeloid lineage, specifically mDC subpopulations and CD14+ monocytes, were able to efficiently induce post-integration HIV-1 latency in non-proliferating CD4+ T-cells in vitro. Inhibition of key pathways involved in mDC-T-cell interactions and HIV-1 latency may provide novel targets to eliminate HIV latency. mRNA profiles of sorted, pure antigen presenting cells including, CD1c+ myleoid dendirtic cells (mDC), SLAN+ mDC, CD14+ monocytes and plasmacytoid DC (pDC), were generated using next generation sequencing in triplicate, using Illumina Illumina Hiseq 2000.
Project description:The preference of HIV to infect activated CD4 T cells has been proposed to contribute to a numerical reduction of antigen-specific T cells and the loss of T cell-mediated immunity. To date, our understanding of how HIV impact on vaccine-induced cellular immunity is limited. Moreover, the influence of chronic inflammation, that persist in treated HIV infection, is still unclear. Here, we investigated inflammation, immune activation and antigen-specific T cell responses in HIV-uninfected and cART-treated HIV people with prior measles virus and tetanus toxoid immunity. Our findings highlight lower antigen-induced T cell activation and lower cytokine production of antigen-specific CD4 T cells in the HIV group. These lower recall CD4 T cell responses associated with high plasma levels of multiple cytokines and with T cell hyperactivation. Transcriptome analysis of sorted antigen-specific CD4 T cells revealed that upon antigen reencounter, HIV people on cART had a reduced expression of gene sets previously reported to associate with vaccine-induced protective immunity against various pathogens. We further identified a consistent impairment of the IFN and IFN signaling pathways as a mechanism for the functional loss of antigen-specific CD4 T cell responses in cART-treated people with HIV. Together, our findings suggest that vaccine-induced cellular immunity may benefit from strategies to counteract inflammation in HIV infection.pecific
Project description:To systematically examine host-virus interaction in HIV infection, we used isobaric tag-based quantitative mass spectrometry to perform a proteomic profiling of HIV infection of human primary CD4 T cells.
Project description:This SuperSeries is composed of the following subset Series: GSE14278: Comparison of CD4+ T cell function between HIV-1 resistant and HIV-1 susceptible individuals (Affymetrix) GSE14279: Comparison of CD4+ T cell function between HIV-1 resistant and HIV-1 susceptible individuals (Immune) Refer to individual Series
Project description:Failures to produce neutralizing antibodies upon HIV-1 infection result in part from B-cell dysfunction due to unspecific B-cell activation. How HIV-1 affects antigen-specific B-cell functions remains elusive. Using an adoptive transfer mouse model and ex vivo HIV infection of human tonsil tissue, we found that expression of the HIV-1 pathogenesis factor NEF in CD4 T cells undermines their helper function and impairs cognate B-cell functions including mounting of efficient specific IgG responses. NEF interfered with T cell help via a specific protein interaction motif that prevents polarized cytokine secretion at the T-cell-B-cell immune synapse. This interference reduced B-cell activation and proliferation and thus disrupted germinal center formation and affinity maturation. These results identify NEF as a key component for HIV-mediated dysfunction of antigen-specific B cells. Therapeutic targeting of the identified molecular surface in NEF will facilitate host control of HIV infection.
Project description:The main obstacle in curing an established HIV-1 infection is the long-lived reservoir of latently infected CD4+ T cells. This reservoir is maintained by T cell expansion that can be activated by several mechanisms including antigen-driven proliferation and homeostatic proliferation (HSP). Antigen-driven proliferation triggered by T cell receptor (TCR) signaling is a strong physiological inducer of CD4+ T cell expansion. This also reactivates latent HIV-1 and thus, can be the source of viral rebound. Unlike antigen-driven proliferation, HSP allows the expansion of HIV-1-infected CD4+ T cells without activating HIV-1 expression. While this condition strongly activates STAT5 signaling, the mechanisms for HIV-1 containment are unknown. Our previous work using HIV-infected primarily CD4+ T cells maintained under HSP conditions suggested a post-transcriptional block as a cause of the containment (Tsunetsugu-Yokota et al. 2016 Front Microbiol). To decipher the mechanisms that contribute to the HIV-1 refractory state in homeostatic proliferating CD4+ T cells, we analyzed differentially expressed genes in primary CD4 + cells that were cultured either under HSP conditions (culture with IL-7 and IL-15) or after TCR-stimulation (culture with IL-2 after anti-CD3/CD28 activation).
Project description:BACKGROUND: Combination antiretroviral therapy (cART) is able to control HIV-1 viral replication, however long-lived latent infection in resting memory CD4+ T-cells persist. The mechanisms for establishment and maintenance of latent infection in resting memory CD4+ T-cells remain unclear. Previously we have shown that HIV-1 infection of resting CD4+ T-cells co-cultured with CD11c+ myeloid dendritic cells (mDC) produced a population of non-proliferating T-cells with latent infection. Here we asked whether different antigen presenting cells (APC), including subpopulations of DC and monocytes, were able to induce post-integration latent infection in resting CD4+ T-cells, and examined potential cell interactions that may be involved using RNA-seq. RESULTS: mDC (CD1c+), SLAN+ DC and CD14+ monocytes were most efficient in stimulating proliferation of CD4+ T-cells during syngeneic culture and in generating post-integration latent infection in non-proliferating CD4+ T-cells following HIV-1 infection of APC-T-cell co-cultures. In comparison, plasmacytoid DC (pDC) and B-cells did not induce latent infection in APC-T-cell co-cultures. We compared the RNA expression profiles of APC subpopulations that could and could not induce latency in non-proliferating CD4+ T-cells. Gene expression analysis, comparing the mDC, SLAN+ DC and CD14+ monocyte subpopulations to pDC identified 53 upregulated genes that encode proteins expressed on the plasma membrane that could signal to CD4+ T-cells via cell-cell interactions (32 genes), immune checkpoints (IC) (5 genes), T-cell activation (9 genes), regulation of apoptosis (5 genes), antigen presentation (1 gene) and through unknown ligands (1 gene). CONCLUSIONS: APC subpopulations from the myeloid lineage, specifically mDC subpopulations and CD14+ monocytes, were able to efficiently induce post-integration HIV-1 latency in non-proliferating CD4+ T-cells in vitro. Inhibition of key pathways involved in mDC-T-cell interactions and HIV-1 latency may provide novel targets to eliminate HIV latency.
Project description:Understanding why some indidivual resist HIV-1 infection despite continued exposure is an important goal for vaccine development. We compared CD4+ T cell gene expression at baseline and after antigenic stimulation in HIV-1 resistant commercial sex-workers from Nairobi, Kenya to HIV-1 low-risk negative (non-resistant) non-commercial sex-workers using immune-focused gene expression arrays Keywords: Case-control, disease state analysis CD4+ T cells from both HIV resistant and HIV low-risk negative individuals were isolated from PBMC after 24 hours of culture by negative slelction. Total RNA was isolated and gene expression compared using immune-focused expression arrays.
Project description:The clonal expansion of HIV-1-infected CD4+ T cells is a major barrier to cure. Using single-cell ECCITE-seq, we examined the transcriptional landscape, upstream immune regulators, HIV-1 RNA expression, and T cell clonal expansion dynamics of 215,458 CD4+ T cells (267 HIV-1 RNA+ cells and 68 expanded HIV-1 RNA+ T cell clones) from six HIV-1-infected individuals (during viremia and after suppressive antiretroviral therapy) and two uninfected individuals, in unstimulated conditions and after CMV and HIV-1 antigen stimulation. We found that despite antiretroviral therapy, antigen and TNF responses persisted and shaped T cell clonal expansion. HIV-1 resided in Th1 polarized, antigen-responding T cells expressing Bcl-2 family anti-apoptotic genes. HIV-1 RNA+ T cell clones were larger in clone size, established during viremia, persistent after viral suppression, and enriched in GZMB+ cytotoxic effector memory Th1 cells. Targeting HIV-1-infected cytotoxic CD4+ T cells and drivers of clonal expansion provides a new direction for HIV-1 eradication.