Diminished placental Factor XIIIA1 expression associates with pre-conception antiretroviral treatment 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.

Beneficial bacteria activate type-I interferon production via the intracellular cytosolic sensors STING and MAVS.

Type-I interferon (IFN-I) cytokines are produced by immune cells in response to microbial infections, cancer and autoimmune diseases, and subsequently, trigger cytoprotective and antiviral responses through the activation of IFN-I stimulated genes (ISGs). The ability of intestinal microbiota to modulate innate immune responses is well known, but the mechanisms underlying such responses remain elusive. Here we report that the intracellular sensors stimulator of IFN genes (STING) and mitochondrial antiviral signaling (MAVS) are essential for the production of IFN-I in response to lactic acid bacteria (LAB), common gut commensal bacteria with beneficial properties.

Macrophage heterogeneity in tissues: phenotypic diversity and functions.

During development and throughout adult life, macrophages derived from hematopoietic progenitors are seeded throughout the body, initially in the absence of inflammatory and infectious stimuli as tissue-resident cells, with enhanced recruitment, activation, and local proliferation following injury and pathologic insults. We have learned a great deal about macrophage properties ex vivo and in cell culture, but their phenotypic heterogeneity within different tissue microenvironments remains poorly characterized, although it contributes significantly to maintaining local and systemic homeostasis, pathogenesis, and possible treatment. In this review, we summarize the nature, functions, and interactions of tissue macrophage populations within their microenvironment and suggest questions for further investigation.

The role of macrophage class a scavenger receptors in a laser-induced murine choroidal neovascularization model.

Purpose: Laser-induced choroidal neovascularization (CNV) is a widely used model to mimic many features of CNV resulting from wet AMD. Macrophages have been implicated in the pathogenesis of AMD. Class A scavenger receptors, scavenger receptor-A (SR-A) and macrophage receptor with collagenous domain (MARCO), are expressed on macrophages and are associated with macrophage function.