Evaluation of Pre- and Posttransplantation Serum Interferon-Gamma and Soluble CD30 for Predicting Liver Allograft Rejection

Lymphocyte surface molecules as immune activation biomarkers

Immunosuppression is mandatory after solid organ transplantation between HLA mismatched individuals. It is a lifelong therapy that needs to be closely monitored to avoid under- and over-immunosuppression. For many drugs, pharmacokinetic monitoring has been proven to be beneficial. However, the therapeutic ranges are statistically derived surrogate markers for the effects that cannot predict the individual response of single patients. Better tailored immunosuppression biomarkers are needed that indicate immune activation. T cells are critically involved in organ rejection, and the means to assess their activation state may be promising to individualize immunosuppressive therapies. Activated T cells can be monitored with flow cytometry based on surface molecules that are typically up regulated or with molecules that are cleaved off the cell surface. Among these molecules are the interleukin-2 receptor (CD25); transferrin receptor (CD71); the T cell co-stimulatory molecules CD28, CD69, and CD154 and sCD30, which is a member of the TNF-alpha family. The effect of immunosuppressive drugs on T cell activation can be recorded with indirect cell function assays or by directly monitoring activated T cells in whole blood. Soluble proteins can be measured with immunoassays. This review provides a summary of the experimental and clinical studies investigating the potential of surface molecules as a tool for immune monitoring. It critically discusses the obstacles and shortcomings from an analytical and diagnostic perspective that are currently preventing their use in multicenter trials and clinical routine monitoring of transplant patients.

Elevated soluble CD30 characterizes patients with hepatitis C virus-induced liver allograft cirrhosis

Hepatitis C virus (HCV) recurrence after orthotopic liver transplantation (OLT) significantly accelerates progression to allograft cirrhosis. Current biochemical parameters to monitor progression of chronic HCV after OLT have yielded low specificity and sensitivity. Here we investigated the HCV-specific immunity and serum levels of soluble CD30 (sCD30), a novel marker of Th2 immunity, in patients with and without allograft cirrhosis. Patients with hepatic inflammation but no cirrhosis (HIN, n=20) revealed elevated serum interferon (IFN)-gamma and high frequency of IFN-gamma producing CD4 T(h1) cells compared to those with hepatic cirrhosis (HFC, n=20) that had high interleukin (IL)-5 and IL-5 producing CD4 T(h2) cells. Patients with HFC, but not HIN, were found to have significantly higher levels of sCD30. Therefore, we conclude that lack of optimal Th1-type CD4 T cells is associated with HCV-induced allograft cirrhosis. Further, sCD30 may represent a novel marker for surveillance of hepatic cirrhosis in transplant recipients with chronic HCV infection.

Pre-transplant level of soluble CD30 is associated with infection after heart transplantation

BACKGROUND

One immunologic element of the immune system is the CD30 molecule which belongs to the TNF-R superfamily. CD30 can serve as a T-cell signal transducing molecule and is expressed by a subset of activated T lymphocytes, CD45RO(+) memory T cells. Augmentation of soluble CD30 during kidney transplant (Tx) rejection has been reported. Our study was to determine if the level of sCD30 prior to heart transplant (HTx) could categorize the patients (pts) into high or low immunologic risk for post-Tx outcome.

METHODS

Pre-Tx sera from 100 consecutive HTx recipients were studied. sCD30 was detected by ELISA using the commercially available CD30 monoclonal antibody. Level of sCD30 was correlated with two-yr Tx outcome.

RESULTS

Significant correlation was seen between the high level of sCD30 and lower incidence of infection. Four of the 35 pts with pre-Tx high level of sCD30 level (>90 U/mL) developed infection post-Tx. However, 31/65 pts who had a low level of sCD30 (<90 U/mL) developed infection post-transplantation (p < 0.0003). No remarkable differences were noted with the other clinical parameters, including mean hospitalization, 3A biopsy rejection or death.

CONCLUSIONS

We report for the first time that the high level of sCD30 prior to the HTx may be associated with a higher immunologic ability of the pts and therefore, may have a protective effect in the development of infection post-Tx.

Maternal serum soluble CD30 is increased in normal pregnancy, but decreased in preeclampsia and small for gestational age pregnancies

OBJECTIVE

Women with preeclampsia and those who deliver small for gestational age (SGA) neonates are characterized by intravascular inflammation (T helper 1 (Th1)-biased immune response). There is controversy about the T helper 2 (Th2) response in preeclampsia and SGA. CD30, a member of the tumor necrosis factor receptor superfamily, is preferentially expressed in vitro and in vivo by activated T cells producing Th2-type cytokines. Its soluble form (sCD30) has been proposed to be an index of Th2 immune response. The objective of this study was to determine whether the maternal serum concentration of sCD30 changes with normal pregnancy, as well as in mothers with preeclampsia and those who deliver SGA neonates.

METHODS

This cross-sectional study included patients in the following groups: (1) non-pregnant women (N = 49); (2) patients with a normal pregnancy (N = 89); (3) patients with preeclampsia (N = 100); and (4) patients who delivered an SGA neonate (N = 78). Maternal serum concentration of sCD30 was measured by a specific and sensitive enzyme-linked immunoassay. Non-parametric tests with post-hoc analysis were used for comparisons. A p value <0.05 was considered statistically significant.

RESULTS

(1) The median sCD30 serum concentration of pregnant women was significantly higher than that of non-pregnant women (median 29.7 U/mL, range 12.2-313.2 vs. median 23.2 U/mL, range 14.6-195.1, respectively; p = 0.01). (2) Patients with preeclampsia had a significantly lower median serum concentration of sCD30 than normal pregnant women (median 24.7 U/mL, range 7.6-71.2 vs. median 29.7 U/mL, range 12.2-313.2, respectively; p < 0.05). (3) Mothers with SGA neonates had a lower median concentration of sCD30 than normal pregnant women (median 23.4 U/mL, range 7.1-105.3 vs. median 29.7 U/mL, range 12.2-313.2, respectively; p < 0.05). (4) There was no significant correlation (r = -0.059, p = 0.5) between maternal serum sCD30 concentration and gestational age (19-38 weeks) in normal pregnant women.

CONCLUSIONS

(1) Patients with preeclampsia and those who deliver an SGA neonate had a significantly lower serum concentration of sCD30 than normal pregnant women. (2) This finding is consistent with the view that preeclampsia and SGA are associated with a polarized Th1 immune response and, perhaps, a reduced Th2 response.

Value of Soluble CD30 in Liver Transplantation

INTRODUCTION

CD30 is a membrane glycoprotein that belongs to the tumor necrosis factor superfamily. It is expressed on activated T cells. After activation of CD30(+) T cells, a soluble form of CD30 (sCD30) released into the bloodstream, can be measured in the serum. The aim of our study was to investigate the time course of serum levels of sCD30 during hepatic allograft rejection.

MATERIALS AND METHODS

Serum levels of sCD30 were determined in 30 healthy subjects and 50 hepatic transplant recipients. These patients were divided into two groups: group I, 35 patients without rejection; and group II, 15 patients with acute rejection. Samples were collected on day 1 and 7 after transplantation and on the day of liver biopsy.

RESULTS

The concentrations of sCD30 were similar in the rejection (40.4 +/- 16.5 U/mL) and nonrejection groups (43.0 +/- 18.2 U/mL) on postoperative day 1. We observed a significant increase in sCD30 levels in the rejection group on postoperative day 7 (76.3 +/- 61.8 U/mL vs 46.8 +/- 20.5 U/mL; P = .01). The difference increased when a diagnosis of acute rejection had been established: namely 133.0 +/- 113.5 U/mL versus 40.1 +/- 22.0 U/mL; (P = .001). These levels were also significantly higher during the entire postoperative period in all the patients, with or without rejection, than those observed in healthy controls (26.6 +/- 5.3 U/mL; P = .005).

CONCLUSIONS

The release of circulating sCD30 is a prominent feature coinciding with the first episode of hepatic allograft rejection. So, monitoring of sCD30 levels may be useful for the early diagnosis of an acute rejection episode.

Pre- and post-transplant monitoring of soluble CD30 levels as predictor of acute renal allograft rejection

Identification of renal graft candidates at high risk of impending acute rejection (AR) and graft loss may be helpful for patient-tailored immunosuppressive regimens and renal graft survival. To investigate the feasibility with soluble CD30 (sCD30) as predictor of AR, sCD30 levels of 70 patients were detected on day 0 pre-transplant and day 1, 3, 5, 7, 10, 14, 21, and 30 post-transplant. AR episodes in 6 months were recorded and then patients were divided into Group AR (n=11) and Group UC (n=59). Results showed that the patients had higher pre-transplant sCD30 levels than healthy people. A significant decrease of sCD30 was observed on the first day post-transplant and continued until day 14 post-transplant. Soluble CD30 presented a stable level from day 14 to 30 post-transplant. Pre-transplant sCD30 levels of Group AR were much higher than those of Group UC (P<0.001). Patients of Group AR also had higher sCD30 levels than those of Group UC on day 1, 3, 5, 7, 10 and 14 (P<0.001). The sCD30 level presented a significantly delayed decrease in the patients of Group AR. Statistical results showed that the highest value of area under ROC curve (0.95) was obtained on day 5 post-transplant, suggesting that sCD30 levels on day 5 are of high predictive value. Therefore, sCD30 level may be a good marker of increased alloreactivity and of significant predictive value. It's necessary to monitor the variation of sCD30 in the early period post-transplant.

Association of Elevated Pretransplant sCD30 Levels With Graft Loss in 206 Patients Treated With Modern Immunosuppressive Therapies After Renal Transplantation

BACKGROUND

Recent reports suggest that high pretransplant serum levels of soluble CD30 (sCD30) are a risk factor for rejections after kidney transplantation. The aim of our study was to elucidate the predictive value of pretransplant sCD30 levels for kidney transplantation outcome in a single-center patient cohort that has been treated with modern immunosuppressive therapies after transplantation.

METHODS

We retrospectively analyzed sCD30 in multiple pretransplant sera from 206 patients, of whom 174 were transplanted with a cadaveric kidney and 32 patients received an allograft from a living donor. Renal function after transplantation was estimated by measuring serum creatinine and by rejection diagnosis.

RESULTS

We could demonstrate a statistically significant association between increased pretransplant sCD30 values and graft failures (P=0.005). Receiver operating curve analysis revealed a cutoff value of 124 U/mL pretransplant sCD30. A multivariate analysis confirmed pretransplant sCD30 values >124 U/mL (P=0.011) and rejection episodes (P<0.0001) as independent risk factors for graft loss.

CONCLUSION

Our study revealed a strong correlation between pretransplant sCD30 levels and the incidence of graft failure, but we could not confirm that the development of rejection episodes is correlated with pretransplant sCD30 values.