Abstract. An epizootic of subclinical lymphoplasmacytic gastritis occurred in cynomolgus monkeys maintained at our research facility. Gastric pathology data and histologic sections of 63 adolescent monkeys (2.5-3.5 years old) sacrificed during the epizootic were reviewed. Localized to multifocal reddening of the gastric mucosa was noted grossly in 7 of 44 (16%) monkeys harboring Helicobacter pylori, but not in any of 19 monkeys in which these bacteria were not seen. Gastritis, characterized by accentuation of lymphoplasmacytic infiltrates in antral and to a lesser degree cardiac mucosa, occurred in 42 of 63 (67%) monkeys evaluated and in 42 of 44 (93%) monkeys in which H. pylori was observed microscopically. Two monkeys with H. pylori infection had infiltrate scores that overlapped with the upper limit of scores of H. pylori-negative animals. Coincident with accentuated infiltrates were gastric gland epithelial hyperplasia, reduction in mucin content of surface and gland epithelia, and comparatively minor infiltrates of neutrophils in superficial lamina propria and gastric glands. Antral mucosa thickness often exceeded 1.5 to 2 times normal. Antral mucosal erosions occurred in 7 of 44 (16%) monkeys with H. pylori. Argyrophilic bacteria morphologically consistent with H. pylori were present in antral and less commonly cardiac mucosal glands. Intensity of bacterial colonization correlated with lymphoplasmacytic infiltrates (r ϭ 0.754) and hyperplasia (r ϭ 0.700), although responses were quite variable. These bacteria were not detected in fundic mucosa except in instances where parietal cells were substantially depleted in glands coincident with localized increases in lamina propria inflammatory cell infiltrates. Helicobacter heilmannii-like organisms (HHLOs) were present in fundic glands of all 63 monkeys; colonization was often pronounced. Scores for fundic mucosal inflammation did not correlate with presence or intensity of colonization with HHLOs (r ϭ 0.005). Rather, fundic inflammation scores positively correlated with the antral inflammation scores (r ϭ 0.548). Bacteria morphologically, biochemically, and genetically consistent with H. pylori were cultured from gastric mucosal specimens confirming bacterial identification. These findings demonstrate that adolescent cynomolgus monkeys are susceptible to natural infection with H. pylori and develop many morphologic hallmarks of H. pylori-related gastritis in humans.Key words: Animal model; bacteria; gastritis; Gastrospirillum hominis; Helicobacter; Helicobacter heilmannii; Helicobacter pylori; monkey; nonhuman primate; spirochetes; stomach.Spirochetes or spiral-shaped bacteria have long been recognized as constituents of gastric microflora in various mammalian species. 8,29,36,48,55,61,62 38 Most Helicobacter species do not have strict host specificity. Rather, certain species have been isolated from multiple host species and experimental transmission among animal species has been shown. 19,22,31,37,41,52 Suspected zoonotic transmission has also been reported. ...

Background: Public health measures to stem the coronavirus disease 2019 (COVID-19) pandemic are challenged by social, economic, health status, and cultural disparities that facilitate disease transmission and amplify its severity. Prior pre-clinical biomedical technologic advances in nucleic acid-based vaccination enabled unprecedented speed of conceptualization, development, production, and widespread distribution of mRNA vaccines that target SARS-CoV-2’s Spike (S) protein. Design: Twenty-five female and male volunteer fulltime employees at the Providence VA Medical Center participated in this study to examine longitudinal antibody responses to the Moderna mRNA-1273 vaccine. IgM-S and IgG-S were measured in serum using the Abbott IgM-S-Qualitative and IgG2-S-Quantitative chemiluminescent assays. Results: Peak IgM responses after Vaccine Dose #1 were delayed in 6 (24%) and absent in 7 (28%) participants. IgG2-S peak responses primarily occurred 40 to 44 days after Vaccine Dose #1, which was also 11 to 14 days after Vaccine Dose #2. However, subgroups exhibited Strong (n = 6; 24%), Normal (n = 13; 52%), or Weak (n = 6; 24%) peak level responses that differed significantly from each other ( P < .005 or better). The post-peak IgG2-S levels declined progressively, and within 6 months reached the mean level measured 1 month after Vaccine Dose #1. Weak responders exhibited persistently low levels of IgG2-S. Variability in vaccine responsiveness was unrelated to age or gender. Conclusion: Host responses to SARS-CoV-2-Spike mRNA vaccines vary in magnitude, duration and occurrence. This study raises concern about the lack of vaccine protection in as many as 8% of otherwise normal people, and the need for open dialog about future re-boosting requirements to ensure long-lasting immunity via mRNA vaccination versus natural infection.

Two experiments were conducted to evaluate the effect of marble spleen disease virus (MSDV) infection on the immune response of pheasants. In the first, 15 ring-necked pheasants were inoculated orally with cell-culture-propagated MSDV and 15 received saline (controls). On days 7, 21, and 35 postinoculation (PI), all birds received sheep erythrocytes intravenously. Hemagglutination titers to sheep erythrocytes were determined for serum samples collected weekly for 6 weeks. The virus-inoculated group had significantly (P less than 0.05) lower hemagglutination titers than the control group. In the second experiment, 30 pheasants were allotted into two groups as above. Whole blood was collected from each bird weekly for 5 weeks. The blood was cultured in microtiter plates with or without optimum concentrations of concanavalin A. Five of 10 MSDV-inoculated pheasants had significantly depressed T lymphocyte transformation on either day 7 or day 14 PI. Overall, the depression of T lymphocyte transformation was transient and mild.