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Alinde, B.

Publications and source records attributed to Alinde, B..

3 recordsLinked to original sources

Diminished placental Factor XIIIA1 expression associates with long term ART and preterm birth in pregnant people living with HIV.

We previously showed a link between maternal vascular malperfusion and pre-term birth (PTB) in pregnant people living with HIV (PPLH) initiating antiretroviral treatment (ART) before pregnancy, indicating poor placental vascularisation. After measuring antenatal plasma angiogenic factors to seek mechanistic insights, low levels of plasma Factor XIIIA1 (FXIIIA1) and vascular-endothelial-growth-factor (VEGF) was significantly associated with PTB at the time closest to delivery (median 34 weeks) in PPLH initiating ART before pregnancy. Knowing that FXIIIA1 is crucial for haemostasis, angiogenesis, implantation and pregnancy maintenance and that expression is found on placental macrophages (Hofbauer cells), we examined placentae at delivery from matching participants who either initiating ART before pregnancy or during gestation. Highest FXIIIA1 expression was on Hofbauer cells but was significantly lower in PTB regardless of HIV infection, but was significantly lower in PPLH in PTB from women who initiated ART before pregnancy. To test the hypothesis that antiretroviral drugs may disrupt vascularisation in the placenta, we used a human umbilical vein endothelial cell (HUVEC) matrigel angiogenesis assay. We identified that addition of pre-treated FXIIIA1-expressing MCSF-and IL-10-induced placenta-like macrophages with physiological concentrations of tenofovir, 3TC, and efavirenz resulted in significantly inhibited angiogenesis; akin to the inhibition observed with titratable concentrations of ZED1301, an inhibitor of FXIIIA1. Overall, an efavirenz-containing ART combination inhibits vasculogenesis without causing toxicity and likely does so through inhibition of a FXIIIA1-mediated-placental macrophage pathway.

immunology↗

Disrupted memory T cell expansion in HIV-exposed uninfected infants is preceded by premature skewing of T cell receptor clonality.

While preventing vertical HIV transmission has been very successful, the increasing number of HIV-exposed uninfected infants (iHEU) experience an elevated risk to infections compared to HIV-unexposed and uninfected infants (iHUU). Immune developmental differences between iHEU and iHUU remains poorly understood and 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 and differences in the emergence of NK cell populations and T cell memory differentiation between iHEU and iHUU. Specific NK cells observed at birth were also predictive of acellular pertussis and rotavirus vaccine-induced IgG and IgA responses, respectively, at 3 and 9 months of life. T cell receptor V{beta} clonotypic diversity was significantly and persistently lower in iHEU preceding the expansion of T cell memory. Our findings show that HIV/ARV exposure disrupts innate and adaptive immunity from birth which may underlie relative vulnerability to infections.

immunology↗

Stereotypic expansion of Tregulatory and Th17 cells during infancy is disrupted by HIV exposure and gut epithelial damage.

Few studies have investigated immune cell ontogeny throughout the neonatal and early paediatric period, where there is often increased vulnerability to infections. Here, we evaluated the dynamics of two critical T cell populations, regulatory (Treg) cells and Th17 cells, over the first 36 weeks of life. Firstly, we observed distinct CD4+ T cells phenotypes between cord blood and peripheral blood, collected within 12 hours of birth, showing that cord blood is not a surrogate for newborn blood. Secondly, both Treg and Th17 cells expanded in a synchronous fashion over 36 weeks of life. However, comparing infants exposed to HIV in utero, but remaining uninfected (iHEU), with HIV-unexposed uninfected control infants (iHUU), there was a lower frequency of peripheral blood Treg cells at birth, resulting in a delayed expansion, and then declining again at 36 weeks. Focusing on birth events, we found that Treg cells co-expressing CCR4 and 4{beta}7 inversely correlated with plasma concentrations of CCL17 (the ligand for CCR4) and intestinal fatty acid binding protein (iFABP), IL-7 and CCL20. This was in contrast to Th17 cells, which showed a positive association with these plasma analytes. Thus, despite the stereotypic expansion of both cell subsets over the first few months of life, there was a disruption in the balance of Th17 to Treg cells at birth likely being a result of gut damage and homing of newborn Treg cells from the blood circulation to the gut. Key pointsO_LIPhenotypic differences between cord and birth peripheral blood CD4 cells. C_LIO_LISynchronous increase of Th17-Treg cells is disrupted by HIV/ART exposure. C_LIO_LIIntrauterine HIV exposure was associated with epithelial gut damage. C_LI

immunology↗