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The ongoing emergence of SARS-CoV-2 variants poses challenges to the immunity induced by infections and vaccination. We conduct a 6-month longitudinal evaluation of antibody binding and neutralization of sera from individuals with six different combinations of vaccination and infection against BA.5, XBB.1.5, EG.5.1, and BA.2.86. We find that most individuals produce spike-binding IgG or neutralizing antibodies against BA.5, XBB.1.5, EG.5.1, and BA.2.86 2 months after infection or vaccination. However, compared to ancestral strain and BA.5 variant, XBB.1.5, EG.5.1, and BA.2.86 exhibit comparable but significant immune evasion. The spike-binding IgG and neutralizing antibody titers decrease in individuals without additional antigen exposure, and <50% of individuals neutralize XBB.1.5, EG.5.1, and BA.2.86 during the 6-month follow-up. Approximately 57% of the 107 followed up individuals experienced an additional infection, leading to improved binding IgG and neutralizing antibody levels against these variants. These findings provide insights into the impact of SARS-CoV-2 variants on immunity following repeated exposure., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: To evaluate the application effect of an ELISA kit for detection of IgG antibody to Schistosomajaponicum in endemic areas., Methods: In two schistosomiasis endemic villages of Eryuan County, Yunnan Province, there were 505 permanent residents enrolled in the study. Fecal examinations were carried out by using the nylon screen bag-egg concentration method. In paralleled testing, the ELISA kit was used for the villagers to detect the IgG antibody to S. japonicum. The assay was performed daily for 20 consecutive days, and the data were analyzed by comparison with the parasitological examination and by using the L - J quality control chart method., Results: In 505 examinees, 290 were positive by ELISA, with a positive rate of 57.43%. The L-J chart analysis showed that the deviation of A450 value between the quality control sera A and B was within the controllable range. The fecal examination found 20 positives with a positive rate 3.96%. Compared with the fecal examination, the positive consistency rate of the ELISA method reached to 90.00%., Conclusion: The ELISA kit for detection of IgG antibody to S. japonicum is stable, reliable and suitable for the screening of schistosomiasis in the field.

The experiment was to investigate the effect of phytosterol formula on growth performance, immune function, nutrient apparent digestibility and intestinal microflora of piglets. The results showed that the feeding phytosterol formula increased the average daily gain of piglets by 14.73%, and reduced diarrhea rate by 62.21%. The serum test found that growth hormone in serum increased by 18.59%, total protein increased by 13.07%, immunoglobulin G increased by 42.70%, and TNF-α decreased by 24.49%. The apparent digestibility rate of dry matter, crude fat and crude protein was improved and the intestinal microbes was significantly boosted. The experiment indicates that the phytosterol formula significantly improves the immune function of piglets and growth performance, which can be potentially used as an antibiotics replacement products in feed industry. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the study is to demonstrate and understand the acquired immunity in golden hamsters (Mesocricetus auratus) elicited by primary Necator americanus infective third-stage larvae (L3) infection. Hamsters infected with 150 L3 for 1, 2, 3, 6 and 10weeks, were challenged with the same number of L3 and sacrificed 25days post challenge. The primarily infected hamsters exhibited 99–100% protection against subsequent L3 challenge compared to un-infected naive hamsters. The acquired immunity was developed as early as 1week post L3 infection and lasted up to 10weeks. Similar protective immunity was obtained in hamsters infected with N. americanus L3 and then treated orally with a single of 100mg/kg albendazole, followed by challenge with N. americanus L3 4 and 8weeks post-treatment. The infected hamsters exhibited a rise in IgG antibodies against L3 and juvenile adult worm antigens. Histological examination showed that challenging L3 were trapped in the skin of primarily infected hamsters and surrounded or infiltrated by different inflammatory cells. The trapped L3 were damaged and dead followed by the formation of granulomas encasing dead worms. The results demonstrate that hamsters primarily infected with N. americanus L3 develop acquired immunity against re-infection. [Copyright &y& Elsevier]