Apoptosis in proliferative glomerulonephritis: decreased apoptosis expression in lupus nephritis.
BACKGROUND
Apoptosis is a mechanism of cellular death involved in the deletion of cells in hyperplasic processes which has been observed in proliferative glomerulonephritis. Patients with systemic lupus erythematosus (SLE) are known to have defective apoptosis but there is scarce information about apoptosis in the renal lesions of this disease. The present studies were done to evaluate apoptosis in relation to the intensity of proliferation in several glomerulonephritis and the possible association between this relationship and the chronic histologic changes in lupus nephritis.


METHODS
Studies were done in renal biopsies from 19 patients with lupus nephritis (types, IV, Va, Vb) classified with respect to chronicity and activity indexes, five patients with acute poststreptococcal glomerulonephritis, five with idiopathic mesangioproliferative glomerulonephritis, four with membranous glomerulonephritis, four with minimal-change nephrotic syndrome, and three patients with focal segmental sclerosis. Seven normal kidneys which could not be used for transplantation were used as a control group. Apoptosis was determined by in situ DNA nick-end labelling techniques and proliferating cells were identified with a monoclonal antibody antiproliferating cell nuclear antigen (PCNA).


RESULTS
Decreased number of apoptotic cells and a high ratio of PCNA: apoptosis were observed in glomerulus and tubulointerstitium of patients with lupus nephritis when compared to other proliferative glomerulonephritis and controls. In lupus nephritis, glomerular apoptosis had a negative correlation with the chronicity index (r = -0.606 P = 0.005). The number of apoptotic cells in the glomeruli was not correlated with the number of PCNA positive cells in lupus nephritis, in contrast with a striking linear correlation observed in acute poststreptococcal nephritis (r = 0.925, P = 0.024), a disease with excellent prognosis.


CONCLUSIONS
Apoptosis is decreased in proliferative lupus nephritis. Intense proliferation without increment in apoptosis (a high PCNA: apoptosis ratio) is a characteristic of lupus nephritis associated with chronic renal histological changes.
Soto
H
H
Instituto de Investigaciones Clínicas, Facultad de Medicina, Universidad del Zulia, Maracaibo, Venezuela.
Mosquera
J
J
Rodríguez-Iturbe
B
B
Henriquez La Roche
C
C
Pinto
A
A
D000293:Adolescent; D000328:Adult; D017209:Apoptosis; D002455:Cell Division; D005260:Female; D006801:Humans; D007678:Kidney Glomerulus / Q000473:pathology; D008181:Lupus Nephritis / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis
D018809:Proliferating Cell Nuclear Antigen