Related Experiment Videos
Monocyte procoagulant activity and plasminogen activator. Role in human renal allograft rejection
Abstract:
Currently the mechanism of renal allograft rejection is not well understood. This study was designed to determine whether induction of monocyte procoagulant activity (MCPA) is important in the pathogenesis of renal allograft rejection. The MPCA assay was performed utilizing a one stage clotting assay both in normal and in factor-VII-deficient plasma. There was no increase in spontaneous MPCA in 20 patients with endstage renal failure and in 10 patients following abdominal or orthopedic operation, as compared with 20 normal controls. MPCA was assessed daily in 18 patients who had received renal allografts. Rejection episodes (RE) were predicted on the basis of persistent elevation in MPCA as compared with pretransplant levels. Rejection was diagnosed clinically and treated on the basis of standard criteria. Treated RE were compared with those predicted by elevated MPCA, and 3 patients were assessed as having no RE by MPCA and by standard criteria. In 8 RE, MPCA correlated temporally with RE (same day) when compared with standard criteria. In 12 RE, MPCA was predictive of rejection preceding standard criteria by at least 24 hr. There were 7 false-positive predictions on the basis of MPCA; however, there was only 1 false negative. MPCA was shown to be a prothrombinase by its dependence only on prothrombin and fibrinogen for full activity. MPCA may be important in the pathogenesis of allograft rejection, and additionally it may be a useful adjunct in the clinical management of this disease.
Insights
Monocyte procoagulant activity (MCPA) may play a role in renal allograft rejection. Elevated MCPA levels can predict rejection episodes, potentially aiding clinical management.
Area of Science:
- Nephrology
- Immunology
- Hematology
Background:
- The precise mechanisms underlying renal allograft rejection remain incompletely elucidated.
- Monocyte procoagulant activity (MCPA) is a potential factor in transplant rejection pathogenesis.
Purpose of the Study:
- To investigate the role of MCPA induction in the pathogenesis of renal allograft rejection.
- To assess the utility of MCPA as an early predictor of rejection episodes.
Main Methods:
- MCPA assay performed using a one-stage clotting assay in normal and factor-VII-deficient plasma.
- Daily assessment of MCPA in 18 renal allograft recipients.
- Comparison of MCPA levels with clinical diagnosis of rejection episodes (RE).
Main Results:
- No significant increase in spontaneous MCPA was observed in end-stage renal failure patients or post-operation patients compared to controls.
- Elevated MCPA levels predicted rejection episodes in 12 out of 18 patients, preceding clinical diagnosis by at least 24 hours.
- MCPA demonstrated a low false-positive rate (7) and a very low false-negative rate (1), showing temporal correlation with RE in 8 cases.
Conclusions:
- MCPA is likely a prothrombinase, requiring only prothrombin and fibrinogen for activity.
- MCPA may be implicated in the pathogenesis of allograft rejection.
- MCPA shows promise as a valuable adjunct for the clinical management of renal allograft rejection.