RENAL EXPRESSION OF IL-6 AND TNF-ALPHA GENES IN LUPUS NEPHRITIS

These studies were carried out to examine the presence of the inflamma tory cytokines IL-6 and TNF alpha in kidneys of patients with lupus ne phritis as an indicator of their possible role in its pathogenesis. A total of 19 kidney biopsies from patients with type III or IV lupus ne phritis were processed by direct immunofluorescence using monoclonal a nti-IL-6 and TNF alpha antibodies. Local expression of these genes was demonstrated both by in situ hybridization and by reverse transcripta se-PCR amplification of total RNA isolated from kidney tissue. Fifty-t wo percent of the biopsies exhibited IL-6 and TNF alpha deposited alon g the glomeruli and tubules; in situ expression of these cytokines was demonstrated in 6 biopsies with type IV, and 1 with type III nephriti s. Inflammatory cytokines are actively synthesized in the kidneys of p atients with lupus nephritis and therefore, may play a role in its pat hogenesis.