Blood transfusions in liver recipients: a conundrum or a clear benefit in the cyclosporine/tacrolimus era?

The effect of a positive T-lymphocytotoxic crossmatch on clinical outcomes in adult-to-adult living donor liver transplantation

Purpose

There is controversy concerning the effect of a positive T-lymphocytotoxic crossmatch (TLC) on clinical outcomes in adult living donor liver transplantation (LDLT). The aim of this study was to investigate the effect of TLC on clinical outcomes in LDLT and to determine how long a pretransplant positive TLC continues after liver transplantation (LT).

Methods

Between January 2005 and June 2010, 219 patients underwent adult LDLT at National Cancer Center. The TLC test was routinely performed before LDLT. TLC test results were positive in 8 patients (3.7%). Patients were divided into 2 groups according to the result of TLC: positive TLC (n = 8) and negative TLC (n = 211) groups. All patients with a pretransplant positive TLC (n = 6) underwent a TLC test every week until negative conversion of TLC, except 2 patients who refused to receive the TLC test.

Results

Acute cellular rejection, surgical complications and patient or graft survival were not significantly different between both groups. All patients with a positive TLC (n = 6) had a posttransplant negative TLC. The median time to negative conversion of TLC was 1.5 weeks (range, 1 to 3 weeks).

Conclusion

A pretransplant positive TLC does not affect clinical outcomes in adult LDLT. Moreover, T-lymphocytotoxic cross-reactivity disappeared within 3 weeks (range, 1 to 3 weeks) after LT.

Risk factors predicting survival of liver transplantation

Prognostic models were developed for analyzing graft survival in a single-center study consisting of all 388 adult liver transplantations performed during 20 years. Proportional hazard models and generalized linear models were used to assess which risk factors, related to donor and recipient characteristics as well as graft preservation and operation, had an effect on graft survival. The prognostic modeling evidenced favorable trends in graft survival time during the successive quinquennials 1982-1987, 1988-1992, and 1993-1997, in comparison to the referent time period 1998-2002. Significant predictors of graft survival time were donor's age, recipient-donor gender compatibility, recipient's blood group, intraoperative blood transfusion, size of the transplanted organ, and indication for transplantation. Conventional histocompatibility matching did not correlate with graft outcome.

Pre-transplant blood transfusion and cyclosporin A induce long-term hamster cardiac xenograft survival in immunocompetent rats

BACKGROUND

In previous studies we have shown that pre-transplant hamster blood transfusion (HBT) can induce non-responsiveness in the T cell independent immunecompartment and result in tolerance towards hamster cardiac xenografts (Xgs) in T cell deficient athymic nude rats. In this study we test the combination of pre-transplant HBT with cyclosporin A (CSA) in immunocompetent Lewis rats.

METHODS

Before transplantation of a hamster cardiac Xg, 1 ml hamster blood was administered to nude rats or Lewis rats. CSA dissolved in olive oil was given orally at varying doses. Anti-hamster antibodies were measured by flowcytometry.

RESULTS

In nude rats HBT 3 days before transplantation resulted in 100% long-term survival >100 days (n=9). In Lewis rats, HBT resulted in hyperacute rejection (HAR) (n=6). Treatment of nude rats with CSA at doses varying from five to 20 mg/kg/day and treatment of Lewis rats with CSA five or 10 mg/kg/day did not effect Xg survival. However, treatment of Lewis rats with CSA 20 mg/kg/day led to long-term survival of five of nine Xgs (p <0.01). Combination of HBT with CSA 10 mg/kg/day in Lewis rats resulted in long-term survival of four of seven Xgs. HBT and CSA 20 mg/kg/day resulted in 100% long-term survival (n=9). Immunoglobulin M (IgM) increased after HBT and CSA in these Lewis rats, but decreased after transplantation and remained low over time. When CSA was discontinued, IgM increased and Xgs were rejected (n=3).

CONCLUSIONS

This study confirms that pre-transplant HBT results in long-term survival of hamster cardiac Xgs in nude rats. HBT and CSA have strong synergistic effects in immunocompetent Lewis rats. Combination of HBT with CSA treatment leads to long-term Xg survival in Lewis rats, whereas HBT alone results in HAR. The presence of T cells has a dominant influence on Xg survival after pre-transplant blood transfusion.

Leukoreduction and acute rejection in liver transplantation: An interim analysis

BACKGROUND

Little is known about the effect of blood transfusions and leukoreduction on acute rejection in liver transplantation. The purpose of this study was to assess the impact of leukoreduction on the occurrence of early rejection episodes in liver transplantation.

METHODS

In 1999, mandatory leukoreduction was implemented in our program. Data from 339 consecutive liver transplant recipients were analyzed with attention to the time period as a proxy for leukoreduction, the number of transfusions, the wait list status, the hepatitis B or C status, the recipient age, and the type of immunosuppression.

RESULTS

Using an early (6-month) rejection-free graft survival model, we observed that introduction of leukoreduction was independently associated with fewer rejection episodes (P =.001). Despite the lower rejection rate, due to a regimen of tacrolimus and antithymocyte globulin, the effect of implementation of leukoreduction remained significant (P =.021).

CONCLUSION

The use of leukoreduction is associated with fewer early rejections, irrespective of the type of immunosuppression. These data support an exploration of the immunomodulatory effect of leukoreduction.

Leukocyte reduction during orthotopic liver transplantation and postoperative outcome: a pilot study

STUDY OBJECTIVE

To investigate the effect of intraoperative leukocyte reduction of administered blood products on the incidence of acute cellular rejection and postoperative patient outcome.

DESIGN

Prospective, nonrandomized, historical control study.

SETTING

Academic tertiary medical center.

PATIENTS

The study group (Group 1) consisted of 30 consecutive adult patients with end-stage liver disease scheduled to undergo orthotopic liver transplantation (OLT) between 1998 and 2000. The historical control group (Group 2) consisted of 30 adult patients with end-stage liver disease matched to study group patients as closely as possible for age, gender, and etiology of liver disease who underwent OLT between 1995 and 1999.

INTERVENTIONS

Group 1 patients had all intraoperative allogeneic and cell salvaged blood products leukocyte reduced before administration. Group 2 patients underwent OLT without leukocyte filtration of any administered blood products.

MEASUREMENTS

Demographic data were collected for both patient groups and included age, gender, etiology of liver disease, and both intraoperative and postoperative immunosuppression. Demographic allograft donor data for both patient groups were collected and included age, gender, use of vasopressors during procurement, and cold and warm donor organ ischemic times. Outcome variables measured included incidence of acute cellular rejection, length of intensive care unit (ICU) and length of hospital stay, incidence of both graft loss and retransplantation, and mortality.

MAIN RESULTS

The incidence of acute cellular rejection was 40% in Group 1 and 66.7% in Group 2 (p = 0.037). Length of ICU stay was 3.0 (2.0, 5.0) days in Group 1 and 4.0 (3.0, 6.0) days in Group 2 (p = 0.16). Length of hospital stay was 14.0 (11.0, 18.0) days in Group 1 and 18.0 (14.0, 27.0) days in Group 2 (p = 0.035). One allograft was lost in Group 2 because of primary nonfunction requiring retransplantation (p = 0.31), and three postoperative deaths occurred in Group 1 as a result of multisystem organ failure (p = 0.08).

CONCLUSIONS

Coincident with leukocyte reduction of all administered blood products during OLT, an improved outcome was observed in Group 1 patients as demonstrated by both a decreased incidence of acute cellular rejection and length of hospital stay.

Acute rejection after renal transplantation is reduced by approximately 50% by prior therapeutic blood transfusions, even in tacrolimus-treated patients

BACKGROUND

The authors investigated the relationship between therapeutic blood transfusion before renal transplantation and rejection rates in cyclosporine- and tacrolimus-treated patients.

METHODS

In one center, 265 consecutive recipients were studied. Protocol induction was with azathioprine, prednisolone, and cyclosporine or tacrolimus; 37% had biopsy-proven acute rejection in the first 6 months and 46% had received zero to two units of blood before transplantation.

RESULTS

Lower risk of rejection was associated with tacrolimus induction (odds ratio [OR], 0.53; 95% confidence interval [CI], 0.29-0.95; P=0.049), prior transfusion of three or more units of blood (OR, 0.54; 95% CI, 0.33-0.90; P=0.024), and older age at transplantation (mean, 44.23 +/- 12.56 [+/- SD] years vs. 38.96 +/- 12.37 years; P=0.001). Multiple logistic regression modeling showed the effect of three or more prior transfusions on acute rejection was as follows: OR, 0.49; 95% CI, 0.29 to 0.83; P=0.008.

CONCLUSIONS

Induction immunosuppression should take account of the higher risk of rejection in patients coming to transplantation who have previously received zero to two units of blood.

Pre-transplant blood transfusion induces tolerance to hamster cardiac xenografts in athymic nude rats

The effects of pre-transplant blood transfusion vary from induction of antibodies and accelerated graft rejection, to prolonged survival and even tolerance. The beneficial 'transfusion effect' in allotransplantation is believed to be merely T-cell mediated. In xenotransplantation, T-cell independent mechanisms form a major hurdle. In this study we investigated the effects of pre-transplant hamster blood transfusion on the survival of hamster cardiac xenografts in T-cell deficient athymic nude rats. Nude rats rejected xenografts after 3.8 +/- 0.5 d (n = 8), and immunocompetent Lewis rats after 4.0 +/- 0.5 d (n = 8), following a similar IgM response (P = NS). Hamster blood transfusion 3 d before transplantation in nude rats led to an IgM response and long-term xenograft survival in 17/20. Timing was of importance: blood transfusion 7 d before transplantation resulted in 45% long-term xenograft survival (n = 20). Injection of purified hamster erythrocytes, leukocytes or minced heart also led to survival of xenografts for > 100 d in nude rats, but not in all cases. Second xenografts transplanted to long-term survivors did not provoke an IigM response, and were accepted for > 100 d (n = 4). Transfer of serum from long-term survivors to untreated nude rats resulted in survival of xenografts for > 100 d (n = 4). In Lewis rats pre-transplant blood transfusion induced hyperacute rejection of xenografts after 158 +/- 128 min (n = 8, P < 0.01). We conclude that pre-transplant hamster blood transfusion can induce long-term survival of hamster cardiac xenografts in T-cell deficient athymic nude rats. This blood transfusion effect is mediated by humoral factors and can be transferred by serum. Elucidation of underlying mechanisms might provide some insight into xenotransplantation nonresponsiveness of T-cell independent immunefactors.

Universal leukocyte reduction

Leukocyte reduction of blood components, in the United States, is generally reserved for conditions in which a clinical indication has been documented. There is no evidence that either Creutzfeldt-Jakob disease or variant Creutzfeldt-Jakob disease are transmitted by transfusion in humans or that leukocyte reduction of blood components could reduce their transmission. A number of adverse outcomes following transfusion are alleged to be the result of white blood cells. At this point in time, there are insufficient clinical data to justify the universal leukocyte reduction of blood components.

Infiltrating CD45RC- T cells are associated with immunologic unresponsiveness induced by donor class I major histocompatibility complex antigens in rats

It has previously been shown that a single intravenous injection of freshly heparinized donor-specific blood transfusion (DST) before transplantation significantly prolongs the survival of fully allogeneic ACI (RT1a)-to-LEW(RT1(1)) rat hepatic allografts. Additionally, we have shown that pretreatment of LEW rats with PVG.r1 blood, which shares only the RT1.A major histocompatibility complex (MHC) region with ACI, significantly prolongs the survival of ACI hepatic allografts. In this study, we report the cellular identity of hepatic allograft leukocyte infiltrates following transplantation. Fluorescence-activated cell sorting (FACS) analysis revealed that CD4+ T cells infiltrating liver allografts could be divided into two subsets, CD45RC- CD4+ and CD45RC+ CD4+ T cells, and that the ratio of CD45RC- CD4+/CD45RC+ CD4+ T cells was significantly higher in hepatic allografts of recipients pretreated with DST or PVG.r1 blood as compared to untreated allografts. Further, CD8+ T cells that accumulated in the liver grafts could be similarly divided into two subsets, and the ratio of CD45RC- CD8+/CD45RC+ CD8+ T cells was also significantly higher in hepatic allografts of recipients pretreated with DST or PVG.r1 blood. Reverse transcriptase polymerase chain reaction (RT-PCR) analysis revealed that CD45RC- CD4+ T cells harvested from hepatic allografts pretreated with PVG.r1 blood expressed interleukin-4 (IL-4) and interleukin-10 (IL-10), but not interleukin-2 (IL-2) or interferon-gamma (IFN-gamma). In contrast, CD45RC- CD8+ T cells from hepatic allografts pretreated with PVG.r1 blood expressed IL-4, IL-10, and IFN-lambda, but not IL-2. These results indicate that the CD45RC leukocyte common antigen could be used to differentiate CD4+ and CD8+ T cells following pretreatment with DST or PVG.r1 blood. Persistent infiltration of CD45RC- CD4+ and CD45RC- CD8+ T cells, capable of secreting Th2-type cytokines may prevent allograft rejection by causing immunologic unresponsiveness.