Wennerås C, Qadri F, Bardhan P K, Sack R B, Svennerholm A M
Department of Medical Microbiology and Immunology, Göteborg University, Göteborg, Sweden.
Infect Immun. 1999 Dec;67(12):6234-41. doi: 10.1128/IAI.67.12.6234-6241.1999.
Immune responses against enterotoxigenic Escherichia coli (ETEC) were examined in Bangladeshi adults with naturally acquired disease and compared to responses in age-matched Bangladeshi volunteers who had been orally immunized with a vaccine consisting of inactivated ETEC bacteria expressing different colonization factor antigens (CFs) and the B subunit of cholera toxin. B-cell responses in duodenal biopsy samples, feces, intestinal washings, and blood were determined. Because most of the patients included in the study were infected with ETEC expressing CS5, immune responses to this CF were studied most extensively. Vaccinees and patients had comparable B-cell responses against this antigen in the duodenum: the median numbers of antibody-secreting cells (ASC) were 3,300 immunoglobulin A (IgA) ASC/10(7) mononuclear cells (MNC) in the patient group (n = 8) and 1,200 IgA ASC/10(7) MNC in the vaccinees (n = 13) (not a significant difference). Similarly, no statistically significant differences were seen in the levels of duodenal B cells directed against enterotoxin among vaccinees and patients. A comparison of the capacities of the various methods used to assess mucosal immune responses revealed a correlation between numbers of circulating B cells and antibody levels in saponin extracts of duodenal biopsy samples (r = 0.58; n = 13; P = 0.04) after vaccination. However, no correlation was seen between blood IgA ASC and duodenal IgA ASC after two doses of vaccine. Still, a correlation between numbers of CF-specific B cells in blood sampled from patients early during infection and numbers of duodenal B cells collected 1 week later was apparent (r = 0.70; n = 10; P = 0.03).
对患有自然获得性疾病的孟加拉国成年人针对产肠毒素大肠杆菌（ETEC）的免疫反应进行了检测，并与年龄匹配的孟加拉国志愿者的反应进行了比较，这些志愿者口服了一种疫苗，该疫苗由表达不同定植因子抗原（CFs）的灭活ETEC细菌和霍乱毒素B亚单位组成。测定了十二指肠活检样本、粪便、肠道冲洗液和血液中的B细胞反应。由于该研究中的大多数患者感染了表达CS5的ETEC，因此对这种CF的免疫反应进行了最广泛的研究。疫苗接种者和患者在十二指肠中针对该抗原的B细胞反应相当：患者组（n = 8）中抗体分泌细胞（ASC）的中位数为3300个免疫球蛋白A（IgA）ASC/10⁷单核细胞（MNC），疫苗接种者（n = 13）中为1200个IgA ASC/10⁷ MNC（无显著差异）。同样，在疫苗接种者和患者中，针对肠毒素的十二指肠B细胞水平没有统计学上的显著差异。对用于评估黏膜免疫反应的各种方法的能力进行比较发现，接种疫苗后，循环B细胞数量与十二指肠活检样本皂苷提取物中的抗体水平之间存在相关性（r = 0.58；n = 13；P = 0.04）。然而，两剂疫苗接种后，血液IgA ASC与十二指肠IgA ASC之间没有相关性。不过，在感染早期从患者采集的血液中CF特异性B细胞数量与1周后采集的十二指肠B细胞数量之间存在明显的相关性（r = 0.70；n = 10；P = 0.03）。
