Detection of alpha1 integrin in urine of patients with immunoglobulin A nephropathy.
BACKGROUND
The alpha1beta1 integrin is a cell surface membrane heterodimer composed of noncovalently linked alpha1 and beta1 polypeptides that is up-regulated on activated and proliferating mesangial cells.


METHODS
A double-sandwich enzyme-linked immunosorbent assay that detects alpha1 integrin in a specific and dose-dependent manner at concentrations greater than 150 ng/mL was used to evaluate whether intact alpha1 polypeptides are secreted in the urine samples of 29 patients with various kidney diseases and in those of 5 healthy individuals.


RESULTS
alpha1 Integrin was detected in 8 of the 29 patients including 3 of 3 patients with biopsy-proven immunoglobulin A nephropathy and 3 of 3 clinically suspected but non-biopsy-proven immunoglobulin A nephropathy with evidence of active nephritis. No alpha1 integrins were found in samples of 5 healthy controls.


CONCLUSIONS
alpha1 Integrin polypeptides can be detected in human urine, particularly in immunoglobulin A nephropathy. Further extensive studies are required to clarify the significance of secretion of alpha1 integrins in urine of patients with kidney disease.
Bank
Jonathan
J
Laboratory for Immunoregulation, Tel Aviv University, Tel Aviv, Israel.
Ben-David
Aharon
A
Doolman
Ram
R
Sela
Ben-Ami
BA
Bank
Ilan
I
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D005922:Glomerulonephritis, IGA / Q000473:pathology / Q000652:urine*; D006801:Humans; D039423:Integrin alpha1 / Q000652:urine*; D008297:Male; D008875:Middle Aged
D039423:Integrin alpha1