Although many HIV cure strategies seek to expand HIV-specific CD8 + T cells to control the virus, all are likely to fail if cellular exhaustion is not prevented. A loss in stem-like memory properties (i.e., the ability to proliferate and generate secondary effector cells) is a key feature of exhaustion; little is known, however, about how these properties are regulated in human virus–specific CD8 + T cells. We found that virus-specific CD8 + T cells from humans and nonhuman primates naturally controlling HIV/SIV infection express more of the transcription factor TCF-1 than noncontrollers. HIV-specific CD8 + T cell TCF-1 expression correlated with memory marker expression and expansion capacity and declined with antigenic stimulation. CRISPR-Cas9 editing of TCF-1 in human primary T cells demonstrated a direct role in regulating expansion capacity. Collectively, these data suggest that TCF-1 contributes to the regulation of the stem-like memory property of secondary expansion capacity of HIV-specific CD8 + T cells, and they provide a rationale for exploring the enhancement of this pathway in T cell–based therapeutic strategies for HIV.
In untreated HIV infection, CD8 T cell exhaustion (i.e., decreased proliferative and effector capacity) is associated with high levels of expression of coinhibitory receptors, including PD-1, T cell immunoreceptor with Ig and ITIM domains (TIGIT), CD160, and 2B4. This is evident for both HIV-specific and non-HIV-specific CD8 T cells. Antiretroviral therapy (ART) initiated during chronic infection decreases but may not completely normalize the expression of such "exhaustion markers." Compared to initiation of ART later in the course of disease, initiation soon after infection reduces some parameters of chronic inflammation and adaptive immune dysfunction. However, it is not known if Early ART (e.g., initiated within the first 6 months after HIV infection) versus Delayed ART (e.g., initiated during chronic infection) preferentially reduces expression of exhaustion markers. We evaluated exhaustion marker expression on subsets of circulating effector and memory CD8 T cells at longitudinal pre- and post-ART (2 and 5 years on ART) time points from n = 19 (Early ART) and n = 23 (Delayed ART) individuals. Before ART, TIGIT and CD160 were expressed on a statistically significantly higher proportion of effector and transitional memory cells from individuals in the Delayed ART group: the timing of ART initiation, however, did not consistently affect the expression of the exhaustion markers once viral suppression was achieved. Understanding which factors do and do not regulate aspects of CD8 T cell exhaustion, including the expression of exhaustion markers, is critical to inform the rational design of CD8 T cell-based therapies to treat HIV, for which CD8 T cell exhaustion remains an important barrier to efficacy.
Background: Reversing or preventing T-cell exhaustion is an important treatment goal in the context of HIV disease; however, the mechanisms that regulate HIV-specific CD8+ T-cell exhaustion are incompletely understood. Since mitochondrial mass (MM), mitochondrial membrane potential (MMP), and cellular reactive oxygen species (ROS) content are altered in exhausted CD8+ T cells in other settings, we hypothesized that similar lesions may arise in HIV infection. Methods: We sampled cryopreserved peripheral blood mononuclear cells from HIV-uninfected (n = 10) and HIV-infected participants with varying levels and mechanisms of viral control: viremic (VL > 2000 copies/mL; n = 8) or aviremic (VL < 40 copies/mL) due to antiretroviral therapy (n = 11) or natural control (n = 9). We characterized the MM, MMP, and ROS content of bulk CD8+ T cells and MHC class I tetramer+ HIV-specific CD8+ T cells by flow cytometry. Results: We observed higher MM, MMP, and ROS content across bulk effector-memory CD8+ T-cell subsets in HIV-infected compared with HIV-uninfected participants. Among HIV-specific CD8+ T cells, these features did not vary by the extent or mechanism of viral control but were significantly altered in cells displaying characteristics associated with exhaustion (eg, high PD-1 expression, low CD127 expression, and impaired proliferative capacity). Conclusions: While we did not find that control of HIV replication in vivo correlates with the CD8+ T-cell MM, MMP, or ROS content, we did find that some features of CD8+ T-cell exhaustion are associated with alterations in mitochondrial state. Our findings support further studies to probe the relationship between mitochondrial dynamics and CD8+ T-cell functionality in HIV infection.
Although many HIV cure strategies seek to expand HIV-specific CD8+ T cells to control the virus, all are likely to fail if cellular exhaustion is not prevented. A loss in stem-like memory properties (i.e., the ability to proliferate and generate secondary effector cells) is a key feature of exhaustion; little is known, however, about how these properties are regulated in human virus-specific CD8+ T cells. We found that virus-specific CD8+ T cells from humans and non-human primates naturally controlling HIV/SIV infection express more of the transcription factor, TCF-1, than noncontrollers. HIV-specific CD8+ T cell TCF-1 expression correlated with memory marker expression and proliferative capacity and declined with antigenic stimulation. CRISPR-Cas9 editing of TCF-1 in human primary T cells demonstrated a direct role in regulating expansion capacity. Collectively, these data suggest that TCF-1 controls the stem-like memory properties of HIV-specific CD8+ T cells and provides a rationale for enhancing this pathway in T cell-based therapeutic strategies for HIV. [Main Text:]
Preeclampsia is one of the major hypertensive diseases of pregnancy. Genetic factors contribute to abnormal placentation. The inadequate transformation of cytotrophoblasts causes failure of maternal spiral arteries’ remodeling and results in narrow, atherotic-prone vessels, leading to relative placental ischemia. This study aims to explore the possibility of identifying dysregulated gene networks that may offer a potential target in the possible prevention of preeclampsia. We performed a weighted gene correlated network analysis (WGCNA) on a subset of gene expression profiles of placental tissues from severe preeclamptic pregnancies. We identified a gene module (number of genes = 402, GS = 0.35, p = 0.02) enriched for several G-protein-coupled receptor (GPCR)-related genes with significant protein–protein molecular interaction (number of genes = 38, FDR = 0.0007) that may play key roles in preeclampsia. Some genes are noted to play key roles in preeclampsia, including LPAR4/5, CRLR, NPY, TACR1/2, and SFRP4/5, whose functions generally relate to angiogenesis and vasodilation or vasoconstriction. Other upregulated genes, including olfactory and orexigenic genes, serve limited functions in the disease pathogenesis. Altogether, this study shows the utility of WGCNA in exploring possible new gene targets, and additionally reinforces the feasibility of targeting GPCRs that may offer intervention against development and disease progression among severe preeclampsia patients.
Purpose A study among Filipinos revealed that only 15% of patients with diabetes achieved glycemic control, and poor response to metformin could be one of the possible reasons. Recent studies demonstrate how genetic variations influence response to metformin. Hence, the present study aimed to determine genetic variants associated with poor response to metformin. Methods Using a candidate variant approach, 195 adult Filipino participants with newly diagnosed type 2 diabetes mellitus (T2DM) were enrolled in a case-control study. Genomic DNA from blood samples were collected. Allelic and genotypic associations of variants with poor response to metformin were determined using exact statistical methods. Results Several polymorphisms were nominally associated with poor response to metformin (Puncorr < 0.05). The most notable is the association of multiple variants in the SLC2A10 gene—rs2425911, rs3092412, and rs2425904—with common additive genetic mode of inheritance. Other variants that have possible associations with poor drug response include rs340874 (PROX-AS1), rs815815 (CALM2), rs1333049 (CDKN2B-AS1), rs2010963 (VEGFA), rs1535435 and rs9494266 (AHI1), rs11128347 (PDZRN3), rs1805081 (NPC1), and rs13266634 (SLC30A8). Conclusion In Filipinos, a trend for the association for several variants was noted, with further observation that several mechanisms may be involved. The results may serve as pilot data for further validation of candidate variants for T2DM pharmacotherapy.
Introduction. Sulfonylureas (SUs) are commonly used drugs for type 2 diabetes mellitus (T2DM) in the Philippines. This study aimed to associate genetic variants with poor response to gliclazide and glimepiride among Filipinos. Methodology. Two independent, dichotomous longitudinal substudies enrolled 139 and 113 participants in the gliclazide and glimepiride substudies, respectively. DNA from blood samples underwent customized genotyping for candidate genes using microarray. Allelic and genotypic features and clinical associations were determined using exact statistical methods.Results. Three months after sulfonylurea monotherapy, 18 (13%) were found to be poorly responsive to gliclazide, while 7 (6%) had poor response to glimepiride. Seven genetic variants were nominally associated (p<0.05) with poor gliclazide response, while three variants were nominally associated with poor glimepiride response. For gliclazide response, 3 carboxypeptidase-associated variants (rs319952 and rs393994 of AGBL4 and rs2229437 of PRCP) had the highest genotypic association; other variants include rs9806699, rs7119, rs6465084 and rs1234315. For glimepiride response, 2 variants were nominally associated: CLCN6-NPPA-MTHFR gene cluster -rs5063 and rs17367504 -and rs2299267 from the PON2 loci.Conclusion. Genetic variants were found to have a nominal association with sulfonylurea response among Filipinos. These findings can guide for future study directions on pharmacotherapeutic applications for sulfonylurea treatment in this population.
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