Apoptosis and the expression of genes of the Bcl-2 family and TGF-beta1 in rat renal allografts transplanted after donor-specific blood transfusion.
Factors involved in "operational" tolerance in animal models induced by recipient pre-treatment with donor-specific blood transfusion (DSBT) need elucidation. This study examined apoptosis, expression of genes of the Bcl-2 family and of TGF-beta(1) in isografts, rejecting and tolerant allografts.


METHODS
Adult inbred Dark Agouti (DA) kidneys were transplanted, with immediate nephrectomy of recipient kidneys, to (1) ALLO, inbred Albino Surgery (AS) rats; (2) DSBT ALLO, AS rats who received two DA blood transfusions under cover of cyclosporine prior to transplantation; or (3) ISO, DA rats. Grafts were retrieved on day 1, 3, or 5. Apoptosis was assessed by TUNEL. RNA was extracted and reverse transcribed to cDNA for quantification by real-time PCR, relative to the 18s housekeeping gene.


RESULTS
Apoptosis was negligible in ISO while it increased in allograft groups from day 1. On day 5, apoptosis in ALLO (114.0 +/- 30.6), involved renal tubular cells and leukocytes compared to DSBT ALLO (9.7 +/- 4.0) and ISO (0.9 +/- 0.3) involving leukocytes only. On day 1, DSBT ALLO had higher expression of Bax than ALLO or ISO. On day 3, DSBT ALLO and ALLO had higher TGF-beta(1) mRNA than ISO. On day 5, Bcl-2 expression was significantly decreased (P < .001) in ALLO compared to DSBT ALLO and ISO. Bad and Bid were higher in DSBT ALLO than in ALLO. TGF-beta(1) was higher in DSBT ALLO compared to ISO.


CONCLUSIONS
Decreased expression of anti-apoptotic Bcl-2 gene may be implicated in increased apoptosis in rejecting allograft while expression of pro-apoptotic genes may be involved in the establishment of operational tolerance.
Jablonski
P
P
Monash University, Department of Medicine, The Alfred Hospital, Clayton, Australia. Paula.Jablonski@med.monash.edu.au
Goh
B L
BL
Maguire
J
J
Glogowski
I
I
Howden
B O
BO
Thomson
N M
NM
Stein
A N
AN
D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D001803:Blood Transfusion; D005786:Gene Expression Regulation; D019254:Genes, bcl-2 / Q000235:genetics*; D006085:Graft Survival / Q000502:physiology; D020287:In Situ Nick-End Labeling; D016030:Kidney Transplantation / Q000473:pathology / Q000502:physiology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D016212:Transforming Growth Factor beta / Q000235:genetics*; D053773:Transforming Growth Factor beta1; D014184:Transplantation, Homologous / Q000473:pathology / Q000502:physiology; D014185:Transplantation, Isogeneic / Q000502:physiology
C508962:Tgfb1 protein, rat; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1