Periluminal antigen in fetal kidneys

Eighty-nine kidneys obtained from human fetuses, 6-31 weeks of gestational age, were studied for the presence of apical periluminal antigen. Sera of rats in which nephrotic renal disease had been produced and which were known to contain considerable amounts of periluminal antibodies were used. Of the less than 12-week-old fetal kidneys, 24% showed the presence of periluminal antigen and this value increased (up to 100%) in older fetuses. It is believed that this observation favors the concept that this antigen is synthesized in proximal tubular cells rather than reabsorbed into them. This supports the concept that the experimental model is an endogenous complex disease. In accordance with these results, the disease incidence, using human fetal kidneys and kidneys obtained from newborn rats, was 60% and 62%, respectively.