Neutrophils utilize immunoglobulins (Igs) to clear antigen, but their role in Ig production is unknown. Here we identified neutrophils around the marginal zone (MZ) of the spleen, a B cell area specialized in T-independent Ig responses to circulating antigen. Neutrophils colonized peri-MZ areas after post-natal mucosal colonization by microbes and enhanced their B-helper function upon receiving reprogramming signals from splenic sinusoidal endothelial cells, including interleukin 10 (IL-10). Splenic neutrophils induced Ig class switching, somatic hypermutation and antibody production by activating MZ B cells through a mechanism involving the cytokines BAFF, APRIL and IL-21. Neutropenic patients had fewer and hypomutated MZ B cells and less preimmune Igs to T-independent antigens, which indicates that neutrophils generate an innate layer of antimicrobial Ig defense by interacting with MZ B cells.

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SUMMARY BackgroundSome limited studies of coeliac disease have shown higher frequency of coeliac disease in infancy and adolescence than in adulthood. This finding has remained unnoticed and not adequately demonstrated.

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We describe the results of routine obstetric ultrasound examination over a period of 22 years (1970-91) at the Institut Universitari Dexeus, Barcelona, Spain. A total of 1006 malformed fetuses or neonates were identified at abortion or delivery. The prevalence of fetal abnormalities was 3.03%. Fetal anomalies were diagnosed antenatally in 788 (78.33%) cases. Early prenatal diagnosis (before 22 weeks of gestation) was made in 598 (59.44%) cases. The detection of malformed fetuses increased from 19.75% in the first phase of the study (1970-74) to 96.33% in the last phase (1990-91). The specificity of the method was over 99% throughout the study period. The most frequently diagnosed anomalies were urinary tract anomalies (22.86% of cases), followed by head and neck anomalies (18.68%), musculoskeletal anomalies (8.64%), heart anomalies (7.35%) and gastrointestinal anomalies (7.35%). The earliest diagnosed malformations were those of the thoracoabdominal wall (81.08%), followed by defects of the urinary tract (70.86%) and of the diaphragm (70.83%).