Prevention of Acute Immunologic Lung Change in Rats by an Isolated Urine Fraction

Abstract
Protection against the acute lung damaging effect of nephrotoxic sera was obtained in rats by previous injection of a component of normal rat urine. This component is defined as an early fraction in the elution pattern of urinary proteins filtered through a column of sephadex G-200. In preliminary experiments the same protective effect was observed following the injection of whole dialysed urine. It is suggested that the activity of mediators of the tissue changes that follow antigen-antibody reaction may somehow be interfered with by that urinary fraction. The retention of the same substance might be responsible for one of the mechanisms possibly involved in uraemic Immunologlc tolerance.