CD103 mRNA levels in urinary cells predict acute rejection of renal allografts.
BACKGROUND
CD103 is displayed on the cell surface of alloreactive CD8 cytotoxic T lymphocytes (CTLs) and is a critical component for the intraepithelial homing of T cells. Because intratubular localization of mononuclear cells is a feature of acute cellular rejection of renal allografts, we explored the hypothesis that CD103 messenger (m)RNA levels in urinary cells predict acute rejection.


METHODS
We collected 89 urine specimens from 79 recipients of renal allografts. RNA was isolated from the urinary cells, and we measured CD103 mRNA levels and a constitutively expressed 18S ribosomal (r)RNA with the use of real-time quantitative polymerase chain reaction assay.


RESULTS
CD103 mRNA levels, but not 18S rRNA levels, were higher in urinary cells from 30 patients with an episode of acute rejection (32 biopsies and 32 urine samples) compared with the levels in 12 patients with other findings on allograft biopsy (12 biopsies and 12 urine samples), 12 patients with biopsy evidence of chronic allograft nephropathy (12 biopsies and 12 urine samples), and 25 patients with stable graft function after renal transplantation (0 biopsies and 33 urine samples) (P = 0.001; one-way analysis of variance). Acute rejection was predicted with a sensitivity of 59% and a specificity of 75% using natural log-transformed value 8.16 CD103 copies per microgram as the cutoff value (P = 0.001).


CONCLUSIONS
CD103 mRNA levels in urinary cells are diagnostic of acute rejection of renal allografts. Because CD103 is a cell surface marker of intratubular CD8 CTLs, a noninvasive assessment of cellular traffic into the allograft may be feasible by the measurement of CD103 mRNA levels in urinary cells.
Ding
Ruchuang
R
2 Division of Nephrology, Department of Medicine, Department of Transplantation Medicine, Weill Medical College of Cornell University, New York-Presbyterian Hospital, New York, NY.
Li
Baogui
B
Muthukumar
Thangamani
T
Dadhania
Darshana
D
Medeiros
Mara
M
Hartono
Choli
C
Serur
David
D
Seshan
Surya V
SV
Sharma
Vijay K
VK
Kapur
Sandip
S
Suthanthiran
Manikkam
M
D000208:Acute Disease; D000328:Adult; D015703:Antigens, CD / Q000235:genetics / Q000652:urine*; D001706:Biopsy; D005260:Female; D005544:Forecasting; D006084:Graft Rejection; D006801:Humans; D039001:Integrin alpha Chains / Q000235:genetics; D007668:Kidney / Q000473:pathology; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000652:urine; D012372:ROC Curve; D014184:Transplantation, Homologous; D014556:Urine / Q000166:cytology
D015703:Antigens, CD; D039001:Integrin alpha Chains; D012333:RNA, Messenger; C091367:alpha E integrins