Clearance of polymeric IgA aggregates in humans.
Clearance of aggregated human secretory immunoglobulin A (AHS-IgA) was studied in nine patients affected by primary IgA nephropathy (IgAGN) and six normal volunteers from the medical staff. Samples of whole blood, erythrocytes, and serum were taken from 3 to 120 minutes after injection of 0.5 mg of 131iodine-labeled AHS-IgA. No significant radioactivity was recorded on erythrocytes. The clearance curve of AHS-IgA from the circulation, calculated by measuring trichloroacetic acid precipitable radioactivity in serum, was found to be biexponential with an initial fast component significantly prolonged in patients (mean half-time, 19.4 minutes, range, 14 to 26 minutes) compared with controls (mean, 12.2 minutes, range, 7.6 to 16.8 minutes; P less than 0.01). These data indicate that clearance of aggregated polymeric IgA does not involve the erythrocyte transport system and seems to be defective in IgAGN patients.
Roccatello
D
D
Divisione Nefrologia e Dialisi, Ospedale Nuova Astanteria Martini, Torino, Italia.
Picciotto
G
G
Coppo
R
R
Piccoli
G
G
Molino
A
A
Cacace
G
G
Amore
A
A
Amoroso
A
A
Quattrocchio
G
G
Sena
L M
LM
D000328:Adult; D000368:Aged; D000936:Antigen-Antibody Complex / Q000276:immunology; D001774:Blood Chemical Analysis; D006680:HLA Antigens / Q000032:analysis / Q000145:classification; D006801:Humans; D007071:Immunoglobulin A, Secretory / Q000378:metabolism* / Q000652:urine; D007674:Kidney Diseases / Q000276:immunology / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D011108:Polymers; D012016:Reference Values
D000936:Antigen-Antibody Complex; D006680:HLA Antigens; D007071:Immunoglobulin A, Secretory; D011108:Polymers