Glomeruli of experimental animals that showed spontaneous recovery from glomerulonephritis when injected with nephrotoxic serum showed higher levels of 12/15-LO mRNA and increased glomerular IL-4 mRNA, suggesting that T cell-derived IL-4 may regulate the expression of 12/15-LO during glomerulonephritis. This evidence concerns the gene IL4 and glomerulonephritis.