Differential expression of glycogenes in tonsillar B lymphocytes in association with proteinuria and renal dysfunction in IgA nephropathy.
Aberrant O-glycosylation of serum and tonsillar IgA1 is one of the main pathogeneses of IgA nephropathy (IgAN). However, the synthesis of underglycosylated IgA1 in tonsils has not yet been characterized. This study examined tonsillar B lymphocytes of IgAN (n=34) using tonsils derived from patients with chronic tonsillitis (n=24) and sleep apnea syndrome (n=14) as a control. Gene expression of beta1,3-galactosyltransferase (beta3GalT), and the core 1 beta3GalT-specific molecular chaperone, Cosmc, UDP-N-acetyl-alpha-D-galactosamine: polypeptide N-acetylgalactosaminyl-transferase 2, were significantly decreased in tonsillar CD19-positive B lymphocytes from IgAN patients compared to control tonsillar tissues as determined by real-time RT-PCR. Tonsillar B cell beta3GalT gene expression significantly correlated with estimated GFR and negatively correlated with proteinuria and histological injury score. Western blotting showed the protein expression of beta3GalT in the tonsils to significantly decrease in IgAN in comparison to the controls. These data suggest the downregulation of beta3GalT in tonsillar B lymphocytes to be closely associated with the clinical characteristics of IgAN.
Department of Medicine and Clinical Science, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Tatsuyuki
T
Inoue
Hitoshi
H
Sugiyama
Yoshiyuki
Y
Hiki
Keiichi
K
Takiue
Hiroshi
H
Morinaga
Masashi
M
Kitagawa
Yohei
Y
Maeshima
Kunihiro
K
Fukushima
Kazunori
K
Nishizaki
Hirofumi
H
Akagi
Yoshiki
Y
Narimatsu
Hisashi
H
Narimatsu
Hirofumi
H
Makino
D000293:Adolescent; D000328:Adult; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism*; D001483:Base Sequence; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D017931:DNA Primers / Q000235:genetics; D005260:Female; D005700:Galactosyltransferases / Q000235:genetics; D015870:Gene Expression; D005922:Glomerulonephritis, IGA / Q000235:genetics* / Q000276:immunology* / Q000503:physiopathology; D006031:Glycosylation; D006801:Humans; D007070:Immunoglobulin A / Q000737:chemistry / Q000378:metabolism; D007668:Kidney / Q000276:immunology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D018832:Molecular Chaperones / Q000235:genetics; D017350:N-Acetylgalactosaminyltransferases / Q000235:genetics; D014066:Palatine Tonsil / Q000276:immunology; D011507:Proteinuria / Q000235:genetics / Q000276:immunology; D055815:Young Adult; D000097763:Polypeptide N-acetylgalactosaminyltransferase
D017931:DNA Primers; D005700:Galactosyltransferases; D007070:Immunoglobulin A; D018832:Molecular Chaperones; D017350:N-Acetylgalactosaminyltransferases; D000097763:Polypeptide N-acetylgalactosaminyltransferase; C505369:C1GALT1C1 protein, human