Th2 predominance at the single-cell level in patients with IgA nephropathy.
BACKGROUND
Abnormalities of lymphocyte function have been reported to be involved in the pathogenesis of IgA nephropathy (IgA-N). The aim of this study was to investigate helper T (Th) predominance at the single-cell level, one of the abnormalities of lymphocyte function in IgA-N.


METHODS
Using flowcytometry, we assessed the levels of circulating Th cells in IgA-N patients (n=30), and in normal individuals (n=30) based on the expression of intracellular Th1 cytokines for interleukin-2 (IL-2) and interferon-gamma (IFN-gamma), and of intracellular Th2 cytokines for IL-4, IL-10, and IL-13. Because the production of each cytokine had a specific time course, we examined cytokine synthesis at 3, 6, 9, and 12 h after stimulation.


RESULTS
The percentages of IL-2-positive Th cells from IgA-N patients were significantly lower than in normal individuals at 6, 9, and 12 h, with the difference becoming greater with time. The number of IFN-gamma-positive Th cells in IgA-N patients was significantly lower than in normal individuals at 9 h, and the number of IFN-gamma-positive Th cells increased more at 12 h than at 3 h in both groups. IL-4 and IL-13 expression was increased in patients with IgA-N at 6 h compared with normal individuals. In IgA-N patients, the percentage of IL-10-positive Th cells was significantly higher than that in normal individuals at each time-point.


CONCLUSIONS
A polarization toward Th2 response at the stimulated lymphocyte level may lead to immune abnormalities in IgA-N.
Ebihara
I
I
Department of Internal Medicine, Institute of Clinical Medicine, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba, Ibaraki 305-8575, Japan.
Hirayama
K
K
Yamamoto
S
S
Muro
K
K
Yamagata
K
K
Koyama
A
A
D000328:Adult; D000368:Aged; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D005434:Flow Cytometry; D005922:Glomerulonephritis, IGA / Q000097:blood*; D006801:Humans; D007378:Interleukins / Q000097:blood; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D018418:Th2 Cells / Q000378:metabolism / Q000473:pathology*; D013997:Time Factors
D016207:Cytokines; D007378:Interleukins