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Abstract Background Helicobacter pylori (H. pylori) infection is ubiquitous in sub-Saharan Africa, but paradoxically gastric cancer is rare. Methods Sera collected during a household-based survey in rural Tanzania in 1985 were tested for anti-H. pylori IgG and IgG subclass antibodies by enzyme immunoassay. Odds ratios (OR) and confidence intervals (CI) of association of seropositivity with demographic variables were computed by logistic regression models. Results Of 788 participants, 513 were aged ≤17 years. H. pylori seropositivity increased from 76% at 0–4 years to 99% by ≥18 years of age. Seropositivity was associated with age (OR 11.5, 95% CI 4.2–31.4 for 10–17 vs. 0–4 years), higher birth-order (11.1; 3.6–34.1 for ≥3rd vs. 1st born), and having a seropositive next-older sibling (2.7; 0.9–8.3). Median values of IgG subclass were 7.2 for IgG1 and 2.0 for IgG2. The median IgG1/IgG2 ratio was 3.1 (IQR: 1.7–5.6), consistent with a Th2-dominant immune profile. Th2-dominant response was more frequent in children than adults (OR 2.4, 95% CI 1.3–4.4). Conclusion H. pylori seropositivity was highly prevalent in Tanzania and the immunological response was Th2-dominant. Th2-dominant immune response, possibly caused by concurrent bacterial or parasitic infections, could explain, in part, the lower risk of H. pylori-associated gastric cancer in Africa.

Background/Objectives : Macrophages play a pivotal role in various pathogenic processes, necessitating the development of efficient differentiation techniques to meet the high demand for these cells in research and therapy. Human macrophages can be obtained via culturing peripheral blood monocytes; however, this source has limited yields and requires patient contact for each proposed use. In addition, it would be difficult to perform gene editing on peripheral blood monocytes. The objectives of this study are to define a robust and consistent method for the differentiation of induced pluripotent stem cells (iPSCs) into macrophages that can address these needs for recurrent studies with high yields and the potential for gene editing. Methods : We refined the traditional embryoid body-based differentiation strategy to create a novel three-phase method that optimizes yield, consistent quality, and reproducibility. This approach incorporates microwell plates and cell filtration to standardize the production of embryoid bodies and subsequent macrophage progenitors. Using up to five independent iPSC donors, we performed several assays for macrophage functions and polarization, such as marker protein staining by flow cytometry, lipoprotein uptake, phagocytosis, cytokine release, inflammasome activation, and the effects of M1-like and M2-like polarization. RNA sequencing was performed to determine the segregation of cells at different stages of differentiation and by iPSC donor, as well as to identify marker genes for each stage of differentiation. Results : The iPSC-derived macrophages generated through this method exhibit characteristic features and cell marker proteins, as well as classical macrophage activities, including lipoprotein uptake, bacterial phagocytosis, cytokine release, and inflammasome activation. We demonstrate the effects of M1-like and M2-like polarization on cytokine release. The first three principal components of the RNA sequencing data showed clear clustering by differentiation stage. In contrast, the fourth and fifth principal components clustered the differentiated macrophages by their respective iPSC donor. Marker genes were identified for each stage of differentiation and polarization. Conclusions : The methods provide an optimized and simplified procedure to produce iPSC-derived macrophages. Our results demonstrate the reproducibility of this method in generating high-quality macrophages suitable for a variety of biomedical applications.

Background: Pyroptosis executor GsdmD (gasdermin D) promotes atherosclerosis in mice and humans. Disulfiram was recently shown to potently inhibit GsdmD, but the in vivo efficacy and mechanism of disulfiram's antiatherosclerotic activity is yet to be explored., Methods and Results: We used human/mouse macrophages, endothelial cells, and smooth muscle cells and a hyperlipidemic mouse model of atherosclerosis to determine disulfiram antiatherosclerotic efficacy and mechanism. The effects of disulfiram on several atheroprotective pathways such as autophagy, efferocytosis, phagocytosis, and gut microbiota were determined. Atomic force microscopy was used to determine the effects of disulfiram on the biophysical properties of the plasma membrane of macrophages. Disulfiram-fed hyperlipidemic apolipoprotein E -/- mice showed significantly reduced interleukin-1β release upon in vivo Nlrp3 (NLR family pyrin domain containing 3) inflammasome activation. Disulfiram-fed mice showed smaller atherosclerotic lesions (~27% and 29% reduction in males and females, respectively) and necrotic core areas (~50% and 46% reduction in males and females, respectively). Disulfiram induced autophagy in macrophages, smooth muscle cells, endothelial cells, hepatocytes/liver, and atherosclerotic plaques. Disulfiram modulated other atheroprotective pathways (eg, efferocytosis, phagocytosis) and gut microbiota. Disulfiram-treated macrophages showed enhanced phagocytosis/efferocytosis, with the mechanism being a marked increase in cell-surface expression of efferocytic receptor MerTK. Atomic force microscopy analysis revealed altered biophysical properties of disulfiram-treated macrophages, showing increased order-state of plasma membrane and increased adhesion strength. Furthermore, 16sRNA sequencing of disulfiram-fed hyperlipidemic mice showed highly significant enrichment in atheroprotective gut microbiota Akkermansia and a reduction in atherogenic Romboutsia species., Conclusions: Taken together, our data show that disulfiram can simultaneously modulate several atheroprotective pathways in a GsdmD-dependent as well as GsdmD-independent manner.

Pyroptosis executor Gasdermin (GsdmD) promotes atherosclerosis in mice and humans. Disulfiram (DSF) was recently shown to potently inhibit GsdmD, but the in-vivo efficacy and mechanism of DSF's anti-atherosclerotic activity is yet to be explored. We used human/mouse macrophages and a hyperlipidemic mouse model of atherosclerosis to determine DSF anti-atherosclerotic efficacy and mechanism. DSF-fed hyperlipidemic apoE -/- mice showed significantly reduced IL-1β release upon in-vivo Nlrp3 inflammasome assembly and showed smaller atherosclerotic lesions (∼27% and 29% reduction in males and females, respectively). The necrotic core area was also smaller (∼50% and 46% reduction in DSF-fed males and females, respectively). DSF induced autophagy in macrophages, hepatocytes/liver, and in atherosclerotic plaques. DSF modulated other atheroprotective pathways such as efferocytosis, phagocytosis, and gut microbiota. DSF-treated macrophages showed enhanced phagocytosis/efferocytosis, with a mechanism being a marked increase in cell-surface expression of efferocytic receptor MerTK. Atomic-force microscopy analysis revealed altered biophysical membrane properties of DSF treated macrophages, showing increased ordered-state of the plasma membrane and increased adhesion strength. Furthermore, the 16sRNA sequencing of DSF-fed hyperlipidemic mice showed highly significant enrichment in atheroprotective gut microbiota Akkermansia and a reduction in atherogenic Romboutsia species. Taken together, our data shows that DSF can simultaneously modulate multiple atheroprotective pathways, and thus may serve as novel adjuvant therapeutic to treat atherosclerosis.

A specific genetic variant associated with atrial fibrillation risk, rs17171731, was identified as a regulatory variant responsible for controlling FAM13B expression. The atrial fibrillation risk allele decreases FAM13B expression, whose knockdown alters the expression of many genes in stem cell-derived cardiomyocytes, including SCN2B , and led to pro-arrhythmogenic changes in the late sodium current and Ca 2+ cycling. Fam13b knockout mice had increased P-wave and QT interval duration and were more susceptible to pacing-induced arrhythmias vs control mice. FAM13B expression, its regulation, and downstream effects are potential targets for investigation of patient-specific therapeutics., Competing Interests: This work was supported by the National Institutes of Health (NIH) grants RO1 HL 111314 and P01HL158502 to Drs Chung, Van Wagoner, Barnard, and Smith; an American Heart Association Strategically Focused Research Network grant 18SFRN34110067 to Drs Chung, Van Wagoner, Barnard, and Smith; the NIH National Center for Research Resources for Case Western Reserve University and Cleveland Clinic Clinical and Translational Science Award UL1-RR024989; the Cleveland Clinic Department of Cardiovascular Medicine philanthropy research funds; and the Tomsich Atrial Fibrillation Research Fund. Dr Ponce-Balbuena was supported by an American Heart Association Career Development Award 20CDA35320040. Dr Hsu was supported by NIH training grant T32 GM 088088. Dr Smith was supported by the Geoffrey Gund Endowed Chair for Cardiovascular Research. The Fusion Lumos LC-MS instrument was purchased from the NIH shared instrument grant 1S10OD023436. The authors have reported that they have no relationships relevant to the contents of this paper to disclose., (© 2023 The Authors.)

Background: Transgenic overexpression of apolipoprotein A-I (apoA1) has been shown to delay atherosclerosis lesion progression and promote lesion regression in mouse models; however, apoA1 is subject to oxidation by myeloperoxidase (MPO) and loss of function. The activity of oxidant resistant human apoA1 was compared to unmodified human apoA1 in mouse models of atherosclerosis progression and regression., Methods and Results: Human apoA1 and the MPO oxidant resistant 4WF isoform transgenic mice were bred to LDL receptor deficient (LDLr KO) mice and fed a western-type diet. High level expression of these human apoA1 isoforms did not lead to increased HDL-cholesterol levels on the LDLr KO background. In males and females, lesion progression was studied over time, and both apoA1 and 4WF transgenic mice vs. LDLr KO mice had significant and similar delayed lesion progression and reduced non-HDL cholesterol. Using time points with equivalent lesion areas, lesion regression was initiated by feeding the mice a low-fat control diet containing a microsomal triglyceride transfer protein inhibitor for 7 weeks. Lesions regressed more in the male apoA1 and 4WF transgenics vs. the LDLr KO, but the 4WF isoform was not superior to the unmodified isoform in promoting lesion regression., Conclusions: Both human apoA1 and the 4WF MPO oxidant resistant apoA1 isoform delayed lesion progression and promoted lesion regression in LDLr KO mice, with more pronounced effects in males than females; moreover, the 4WF isoform functioned similarly to the unmodified human apoA1 isoform., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: J.D.S through the Cleveland Clinic is an inventor for a patent (US8536117B2) entitled "Oxidant resistant apolipoprotein A-1 and mimetic peptides. This does not alter our adherence to PLOS ONE policies on sharing data and materials.