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Introduction: Minimizing the inflammatory events that follow intestinal transplantation may influence immediate graft function and improve outcome. Ischemic preconditioning (IPc) has been shown to ameliorate early inflammatory responses, and it may also attenuate the potentially damaging inflammation after intestinal transplantation. Herein, we examine the influence of intestinal IPc on inflammatory indices (tissue expression of ICAM-1, CD11a, and CD44 and serum levels of the soluble ICAM-1, sICAM-1) after heterotopic intestinal transplantation., Methods: Lewis rats received full-length preconditioned or non-preconditioned Brown Norway intestinal allografts in the absence of immunosuppression. Preconditioned grafts were subjected to 1 cycle of 10 minutes of ischemia-reperfusion. Preconditioned and non-preconditioned isografts acted as controls. Blood was collected on alternate days post-transplant, and graft tissue harvested on sacrifice. ICAM-1, CD44, and CD11a expression was determined by immunohistochemistry, and the area of staining was quantified using image analysis. Serum soluble ICAM-1 levels were determined using an R&D Systems Quantikine enzyme immunoassay., Results: (1) IPc ameliorated serum levels of sICAM-1 until severe rejection (day 7) overcame this down-regulation when compared to non-preconditioned allografts (day 3: 34,304 vs 40,479 pg/mL; day 5: 52,441 vs 61,593 pg/mL; day 7: 75,114 vs 73,309 pg/mL; day 9: 72,872 vs 76,314 pg/mL, respectively). (2) ICAM-1 expression was significantly lower in preconditioned allografts (1.02 vs 2.01 mm(2)). (3) CD44 tissue levels were also found to be lower in preconditioned allografts (0.86 vs 1.13 mm(2)). (4) There was a significant relationship between tissue ICAM-1 expression and serum levels of soluble ICAM-1 (P < .02)., Conclusions: IPc improves inflammatory indices in the early stages following intestinal transplantation, and this might lead to a preserved cellular, architectural, and functional graft status. Furthermore, our results support the use of soluble ICAM-1 as a marker of endothelial activation, and thence of inflammation and developing rejection., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: This study monitored the induction of antimurine immunoglobulin antibody responses after the administration of anti-CD4 (OX38) and anti-LFA-1 (WT.1) monoclonal antibodies to DA rats., Methods: Monoclonal antibody was administered i.v. on 3 consecutive days to untransplanted DA rats, and DA recipients of PVG small bowel allografts. Control animals received no monoclonal antibody. Antimurine immunoglobulin antibody levels in serum samples were determined by enzyme immunoassay., Results: No antimurine immunoglobulin antibody was detected in untransplanted animals receiving OX38 alone. Reactivity was apparent in WT.1-treated animals, but this response was totally abrogated by the co-administration of OX38. A combination of OX38 and WT.1 had no effect on allograft recipient survival and antimurine immunoglobulin antibody responses were detected in all allograft recipients, irrespective of the treatment regimen., Conclusions: Although OX38 inhibited the antibody response both to itself and to WT.1 in untransplanted animals, the immune reaction induced by small bowel allograft rejection overcame this inhibitory capacity.

This investigation used flow cytometry to monitor peripheral blood lymphocyte morphology after rat small bowel transplantation. Preliminary studies demonstrated that in vitro activated peripheral blood lymphocytes exhibited increased cell size and granularity as measured by flow cytometric analysis of forward (FSc) and side (SSc) light scatter characteristics. The formation of distinct 'activated' light scatter regions by such lymphoblastoid transformation occurred concomitantly with up-regulated p55IL-2R expression. Heterotopic small bowel transplantation was performed between PVG donor and DA recipient rats without immunosuppression. Animals receiving isografts served as controls. Peripheral blood lymphocyte subsets were identified using appropriate MoAbs, and the light scatter characteristics of each cell subset were determined by backgating strategies. Increased proportions of activated alpha/beta T cell receptor (TCR)-positive cells could be detected in allografted animals as early as day 2 post-transplantation. B cells showed peak activation by day 4, at which time the proportion of activated cells was over two-fold greater than that seen in untransplanted animals--few activated B cells were detected in isografted animals. Resting natural killer (NK) cell light scatter regions only partially overlap with those of resting T and B lymphocytes, but in allografted animals almost the entire NK population fell outside the resting lymphocyte gate by day 2 post-transplantation, an activation state which was maintained until day 4. These findings associate peripheral blood cell subset lymphoblastoid transformation with developing small bowel allograft rejection. Importantly, changes were detected early and prior to the onset of overt rejection. These data suggest that analysis of peripheral blood lymphocyte light scatter properties may provide an insight into in vivo immune status after small bowel transplantation.

This study used flow cytometric analyses to monitor activation antigen expression (MHC class II; interleukin-2 receptor, p55IL-2R and 3.2.3/NKR-P1 antigen) on peripheral blood neutrophils following rat small bowel transplantation. The rat 3.2.3 antigen is a member of the NKR-P1 family of natural killer (NK) cell-associated molecules, which are expressed at high levels on NK cells and lymphokine-activated killer cells, and low levels on at least one T cell subset. Peripheral blood neutrophils in normal animals express very low or undetectable levels of NKR-P1. Detectable levels of NKR-P1 were induced as early as day 1 following small bowel transplantation in all allografted animals, whereas expression was only rarely detected in isografted animals. In addition, NKR-P1 density was significantly higher in allografted animals and was maintained as rejection developed. MHC class II and p55IL-2R expression was also induced following transplantation. The mechanisms of induction and functional relevance of NKR-P1 expression on neutrophils remain to be defined. However, the concomitant increased expression of MHC class II and p55IL-2R suggest NKR-P1 to be a neutrophil activation marker and implicate a potential role for NKR-P1+ neutrophils in small bowel allograft rejection. This hypothesis is further supported by the loss of detectable peripheral blood neutrophils only with developing rejection. Flow cytometric analysis of neutrophil activation antigen expression may be useful for monitoring human small bowel transplant recipients.