Expression and Purification of Staphylococcal Enterotoxin B and Detection of SEB-Specific IgG Antibodies in Allergic Children

Objective This study aims to express and purify staphylococcal enterotoxin B (SEB) and to detect and analyze the levels of SEB-specific IgG antibodies in the serum of children with food or aeroallergen allergies using an enzyme-linked immunosorbent assay (ELISA). Methods SEB protein was expressed and purified in a recombinant pET-28 α (+)-SEB E. coli system. The purified SEB protein was used as an antigen to detect SEB-IgG antibody levels in the serum of 100 clinically confirmed cases of food-allergic and aeroallergen-allergic children, and the results were compared with those of 50 healthy children using ELISA. Results The recombinant SEB protein, with a molecular weight of approximately 35 kDa, was successfully expressed and purified. ELISA results showed that the SEB-IgG antibody levels in the serum of food-allergic and aeroallergen-allergic children (OD450 values of 0.30 ± 0.03 and 0.31 ± 0.04, respectively) were significantly higher than those in the normal control group (0.24 ± 0.05, P < .05). However, there was no significant difference in SEB-IgG antibody levels between food-allergic children and aeroallergen-allergic children ( P > .05). The positive rate of SEB-IgG antibodies was 68% in aeroallergen-allergic children and 56% in food-allergic children. SEB-IgG positivity increased with the number of allergens but was not correlated with the severity of the allergy. Conclusion This study successfully expressed and purified SEB protein in a prokaryotic system. We found that SEB-IgG antibody levels were significantly higher in allergic children compared to healthy controls and were related to the number of allergens. These results suggest an association between SEB exposure and allergic diseases in the pediatric population, highlighting its potential role as an immunomodulator and laying a foundation for further mechanistic and clinical investigations.