Efficacy of plasmapheresis on donor‐specific antibody reduction by HLA specificity in post–kidney transplant recipients

Abstract

BACKGROUND Donor-specific antibodies (DSAs) to HLA antigens can cause acute antibody-mediated rejection (AMR) after kidney transplantation (Txp). Therapeutic plasma exchange (TPE) has been used for AMR treatment; however, DSA reduction rates are inconsistent. We investigated DSA reduction rates by HLA specificity and clinical outcome. STUDY DESIGN AND METHODS Sixty-four courses of TPE for 56 kidney Txp recipients with high DSA were investigated. Dates of TPE procedures and Txp, patients’ age, sex, race, creatinine (Cr), and mean fluorescent intensity (MFI) of DSA were retrieved. MFI reduction rate after one to three TPE and four to six TPE procedures were calculated by HLA DSA specificity in each patient, and the mean reduction rates were compared. The relationship of TPE treatment, MFI or Cr improvement rate, and graft age was also investigated. RESULTS Patients received a mean 6.0 TPE procedures. Most received intravenous immunoglobulin after TPE and immunosuppressives. Forty-two cases (65.6%) had DSA to HLA Class I and 54 cases (84.4%) to Class II, including 32 cases (50.0%) to both. Mean MFI reduction rates after one to three TPE and four to six TPE procedures were 25.7 and 37.1% in HLA Class I, 25.1 and 34.2% in Class II, and 14.3 and 19.9% in DR51-53. The mean Cr improvements at the end of TPE and 3 and 6 months after TPE were 3.41, −0.37, and −0.72%, respectively. CONCLUSION Six TPE procedures decreased DSA more than three TPE procedures, but reduction rate was lower by the second three TPE procedures than the first three TPE procedures. Although the mean Cr improvement was minimal, the treatment has good potential to stop further deterioration of kidney function. Better Cr improvement rate is correlated with the graft age.

Efficacy of therapeutic plasma exchange on angiotensin II type‐1 receptor antibodies on two kidney transplant recipients

“…Our cases show that 1 course of 5–6 TPE treatment, followed by IVIG, successfully reduces AT1RAb level by 20.0% and 55.6%, median 37.8%. This rate is similar to the reduction rates of HLA DSA in kidney transplant recipients with AMR that we previously reported elsewhere . However, the effect of TPE was temporally and AT1RAb rebound and increase over the time were also observed, which indicates that follow‐up of these patients is critical.…”

The apheresis management of patients undergoing transplantation: a concise review

“…While the duration of TPE for the treatment of AMR is dictated by the clinical response and/or antibody level, an ideal protocol is not yet known—a common TPE schedule involves reassessment for a response after five TPEs approximately every other day . In one study, for 56 patients with elevated DSAs treated with an average of six TPEs (to avoid DSA rebound), outcomes tended to be better if the treatments occurred within the first year after transplant compared to after 1 year, although this was not significant . In addition, there were more DSAs found to HLA Class II as compared to HLA Class I antigens (84% vs. 66%) …”

“…In one study, for 56 patients with elevated DSAs treated with an average of six TPEs (to avoid DSA rebound), outcomes tended to be better if the treatments occurred within the first year after transplant compared to after 1 year, although this was not significant . In addition, there were more DSAs found to HLA Class II as compared to HLA Class I antigens (84% vs. 66%) …”

Impact of active antibody‐mediated rejection treatment on donor‐specific antibodies in pediatric kidney transplant recipients

“…Despite these biopsy results, DSA rebound was observed with the class I DSA that initially responded and treatment resistance was observed in class II DSA titers . Yamada et al found DSA class II MFI rebound in their cohort of 56 kidney transplant patients who received four to six PP sessions for AMR treatment. Contrary to previous reports, we observed a sustained reduction in DSA MFI across both classes out to 24 months (when available), so treatment was not associated with a rebound effect.…”