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Rituximab induction therapy in highly sensitized kidney transplant recipients

YIN, Hang; WAN, Hao; HU, Xiao-peng; LI, Xiao-bei; WANG, Wei; LIU, Hang; REN, Liang; ZHANG, Xiao-dong

doi: 10.3760/cma.j.issn.0366-6999.2011.13.002
Original article
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SDC

Background The number of highly sensitized patients is rising, and sensitization can lead to renal transplant failure. The present study aimed to investigate the safety and efficacy of renal transplantation following induction therapy with rituximab in highly sensitized kidney transplant recipients.

Methods Seven highly sensitized kidney transplant recipients who underwent rituximab therapy from December 2008 to December 2009 were retrospectively analyzed. There were 3 men and 4 women, with a mean age of 38.5 years (range, 21–47 years). The duration of hemodialysis was 3–12 months, with a mean duration of 11 months. For 4 patients, this was the second transplant; the previous graft survival time was 2–11 years, with a mean survival time of 5.8 years. All the female recipients had history of multiple pregnancies, and all patients had previously received blood transfusions. All donors were men, with a mean age of 32.5 years (range, 25–37 years). In 2 of the 7 patients, both class I and class II of panel reactive antibody were high; the remaining 5 patients showed either high in class I or in class II of panel reactive antibody. The mean panel reactive antibody value was 31% for class I and 51% for class II respectively. The donors and the recipients had the same blood type, with low lymphocyte cytotoxicity ranging from 2% to 5%. The human leukocyte antigen (HLA) mismatch numbers were from 2 to 4. All patients received tacrolimus (0.1 mg·kg-1·d-1) and mycophenolate mofetil (750 mg twice per day) orally 3 days prior to surgery. All patients received a single dose of 600 mg rituximab (375 mg/m2) infusion on the day before surgery and polyclonal antibody (antithymocyte globulin) on the day of surgery. Postoperative creatinine, creatinine clearance rate, and occurrence of rejection by pathological biopsy confirmation were monitored.

Results No patient had delayed graft function after surgery. Two patients had acute rejection, one on day 7 and the other on day 13 post-surgery. Diagnosis of acute rejections was based on the clinical assessments and pathological biopsy results. According to the Banff 07 classification of renal allograft pathology, one of the patients was Ia and the other was IIa; the C4d staining was negative in both patients. One patient received methylprednisolone plus cyclophosphamide and the other received antithymocyte globulin (ATG) therapy, both leading to successful reversion of the acute rejection. All patients were discharged postoperatively and all had normal renal function during the 7th to 12th month follow-up. Pulmonary infection occurred in 1 patient 4 months after surgery and was successfully cured.

Conclusion Rituximab induction therapy can reduce the occurrence of postoperative humoral rejection in highly sensitized renal transplant recipients, suggesting that kidney transplantation may be safe and effective for these patients.

Chin Med J 2011;124(13):1928–1932

Kidney Transplantation Program, Department of Urology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing 100020, China (Yin H, Wan H, Hu XP, Li XB, Wang W, LiuH, Ren L and Zhang XD)

Correspondence to: Dr. ZHANG Xiao-dong, Kidney Transplantation Program, Department of Urology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing 100020, China (Tel: 86–10–85231747. Fax: 86–10–65930155. Email: zxd581@263.net) preoperative RTX induction therapy from December 2008 to December 2009. The clinical efficacy and complications of these patients are presented.

(Received November 7, 2010)

Edited by SUN Jing

Renal transplantation is the first choice and the most effective method for the treatment of end-stage renal disease. However, some patients, such as highly sensitized patients, may suffer from irreversible acute rejection postoperatively due to the presence of anti-human leukocyte antigen (HLA) antibodies, which presents a high risk for severe graft dysfunction and graft loss,1 leading to renal transplantation failure. The presence of anti-HLA antibodies is often considered as a contraindication to renal transplantation.2 To prevent rejection of the renal transplant in sensitized patients, preformed antibodies against the leukocyte antigens of donors must be reduced or removed before transplantation. Currently, several therapeutic regimens have been developed to deactivate or eliminate the donor-specific antibodies and prevent antibody-mediated rejection, such as preoperative infusion of large-dose intravenous immunoglobulin (IVIg),3 low-dose IVIg combined with plasmapheresis,4 immunoadsorption,5 as well as application of anti-B cell agents or antibody-depleting drugs, such as sirolimus6 and mycophenolate mofetil.7 In addition, the emergence of the new anti-B cell therapy rituximab (RTX) has enabled the successful renal transplantation in highly sensitized patients.

In this study, we reported the successful renal transplantation in 7 highly sensitized recipients using

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METHODS

Patients

The study was approved by the Beijing Chao-Yang Hospital Ethics Committee and all patients signed the written informed consent. Seven highly sensitized patients who received kidney transplants from living relatives from December 2008 to December 2009 were included, 3 were men and 4 were women. The mean age was 38.5 years, ranging from 21 to 47 years. The causes for renal failure were chronic glomerulonephritis in 5 patients, hypertensive nephropathy in 1 patient, and IgA nephropathy in 1 patient. Four patients were twice transplant recipients, with previous graft chronically dysfunction. All of the 4 patients had retained the previous graft. The survival time of the first graft was 2 to 11 years (mean, 5.8 years). All patients had history of blood transfusions. All female patients had history of multiple pregnancies. Patients received hemodialysis for 3 to 21 months, with the mean time of 11 month (Table 1).

Table 1

Table 1

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HLA mismatching and panel reactive antibody (PRA)

All the donors were men with the mean age of 32.5 years, ranging from 25 to 37 years. Each pair of donor and recipient had the same blood type, with the lymphocyte cytotoxicity within 5%. The range of HLA mismatch number was 2 to 4 (Table 1). In 2 patients, both class I and class II of PRA were high, and in the remaining 5 patients, either class I or class II of PRA was high. The mean PRA value was 31% for class I and 51% for class II, respectively.

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Pretreatment methods

All 7 patients received a single intravenous infusion of rituximab 600 mg (375 mg/m2) on the day before surgery and polyclonal antibody or antithymocyte globulin (ATG) 50 mg/d for 3 days postoperation.

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Surgical methods

All donors underwent left nephrectomy through an incision at the 11th intercostal space under general anesthesia. The warm ischemia time was 3 to 5 minutes, with a mean time of 4 minutes. The cold ischemia time was 50–70 minutes, with a mean time of 60 minutes. For each donor, one kidney was placed into the iliac fossa and the kidney artery and vein were anastomosed to the recipient's external iliac artery and vein, respectively.

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Monitoring index

The creatinine (Cr) and creatinine clearance (Ccr) were monitored postoperatively. Renal graft biopsy was carried out when graft rejection was considered, C4d examination and histopathological inspection were carried out concurrently.

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Therapeutic regimen

All patients started oral administration of tacrolimus (0.1 mg-kg−1d−1) plus mycophenolate mofetil (750 mg, twice per day) 3 days before surgery. The postoperative dosage of tacrolimus was adjusted according to the plasma concentration of tacrolimus (the concentration of tacrolimus was maintained at 8–10 ng/ml within the first 3 months postoperatively). In addition to RTX treatment, all transplant recipients received ATG induction therapy. If renal rejection occurred, patients received corticosteroid or ATG treatment. When returning to normal Cr levels, patients received ganciclovir to prevent infection of cytomegalovirus and a synergic sulfonamides compound to prevent infection of Pneumocystis carinii.

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RESULTS

Postoperative graft function

All the 7 patients had normal renal function at the 7th to 12th month follow-up. The Cr and Ccr levels were 77–110 μmol/L and 62–89 ml/min at 1 month after surgery respectively, 69–103 μmol/L and 65–96 ml/min at 3 months after surgery, respectively and 79–109 μmol/L and 65–91 ml/min at 6 months after surgery. The Cr levels were 82–112 μmol/L and the Ccr levels were 60–87 ml/min in 5 patients at 12 months after surgery (Figures 1 and 2).

Figure 1.

Figure 1.

Figure 2.

Figure 2.

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Occurrence of rejection

All recipients had good early-stage renal function recovery. No patient had delayed graft function (DGF). Acute rejection, diagnosed on the basis of clinical assessment and pathological biopsy results, occurred in 1 patient on day 7 and in 1 patient on day 13 post-surgery. According to the Banff 07 classification of renal allograft pathology, one of the patients was Ia and the other was IIa; the C4d staining was negative in both patients. Successful reversion of rejection was achieved following treatment with methylprednisolone (500 mg) plus cyclophosphamide (CTX) 200 mg for 3 days in one patient and ATG 50 mg for 3 days in the other patient (Table 2).

Table 2

Table 2

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Complications

No infections of the wound, urinary tract, or respiratory passage were observed during the perioperative period. During the 7–12 month follow-up, one patient experienced pulmonary aspergillosis infection at 4 months after surgery, which was cured with amphotericin B treatment.

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DISCUSSION

The sensitization refers to the pre-existence of anti-HLA antibodies in the renal transplant recipients. Based on the HLA antibody levels, recipients of renal transplant can be classified to 4 groups: non-sensitized (PRA 0–10%), slightly sensitized (PRA 11%-50%), moderately sensitized (51%-80%), and highly sensitized (PRA >80%).8 In this study, a highly sensitized patient was defined as PRA >30%. The PRA level is a good indication of the degree of sensitization. The HLA antibodies are often produced following exposure of the patients to the allogeneic antigens, which may occur, for example, in patients who may have had a history of pregnancy, blood transfusions, or a previous transplantation.9

In this study, 4 patients were twice transplant recipients. All female recipients had history of multiple pregnancies and all recipients had history of blood transfusions.

Pretransplant sensitization is believed to be related to antibody-mediated rejection of the renal graft. Therefore, the key to a successful renal transplantation in sensitized patients is the reduction or removal of the preexisting HLA antibodies in these patients before transplantation. Cai and Terasaki10 suggested that interventions in the following three areas can help to achieve successful renal transplantation in sensitized patients: (1) inhibition and reduction of antibody-producing cells, (2) removal or blockage of preexisting or newly developed antibodies, and (3) intervention of antibody-mediated tissue injury. A number of recently developed desensitization regimen, such as IVIg, plasmapheresis (PP), low-dose IVIg combined with PP, as well as anti-CD20, anti-CD52, and anti-CD5 antibody induction therapy, and proteinase inhibitors, are based on those three mechanisms.

CD20 is an internal membrane protein, which is often expressed on the surface of B cells and pre-B cells,11 but CD20 antigen is not expressed on hematopoietic stem cells, progenitor B cells, and normal plasma cells. RTX is a chimeric mouse/human monoclonal antibody raised against the CD20 antigen. RTX can specifically bind to normal or malignant pre-B cells and CD20 antigen on the surface of mature B cells. RTX was approved by the US FDA in 1997 for the treatment of recurrent, poorly differentiated refractory or follicular CD20+ B-cell non-Hodgkin's lymphoma. RTX has been studied in clinical trials for the treatment of many autoantibody-mediated diseases, such as immune thrombocytopenic purpura, systemic lupus erythematosus, myasthenia gravis, and rheumatoid arthritis.12

There are three major mechanisms by which RTX depletes B cells: (1) antibody-dependent cell-mediated cytotoxicity, (2) complement-dependent cytotoxicity, and (3) ability to induce apoptosis.13,14 It is also believed that RTX itself can reduce PRA levels. For example, Pescovitz et al15 found that PRA levels and antibody specificity were reduced in most sensitized patients following treatment with RTX. However, some scientists have different opinions; they believe that for patients with PRA >20%, RTX has played a limited role in reducing PRA antibody levels.16 At present, a single-dose preoperative RTX infusion has been adopted at most clinical centers worldwide. Genberg et al17 found that following treatment of patients (n=49) with a single-dose of preoperative RTX (375 mg/m2), peripheral blood B lymphocyte counts started to reduce 24 hours after surgery. B lymphocytes were nearly fully depleted at weeks 3–6, a phenomenon which was maintained for 14–16 months, indicating that RTX has a fast onset of action and long-lasting effects.

The use of anti-CD20 antibody in sensitized recipients is controversial. Some scientists argue that anti-CD20 antibody does not have any effect on plasma cells, even though plasma cells are the major source of rapid antibody production. In addition, given the fact that RTX does not affect existing antibodies in the circulating system, RTX monotherapy would be problematic. RTX might be more effective for sensitized patients if it is used in combination with other antibody-removing strategies. Vo et al18 reported using combination therapy with RTX and IVIg to treat sensitized patients. Successful renal transplantation was achieved in 16 of 20 patients. Mean PRA levels dropped from 77% to 40%. Time on waiting list for transplantation was reduced from 12 years to 5 months. Although the postoperative rejection rate was as high as 50%, of which 30% were antibody-mediated rejection, most rejections occurred at an early postoperative stage and were controlled. The patient and graft survival rates were 100% and 94% up to 1 year, respectively. In our report, lymphocyte cytotoxicity in donors and recipients were low. Based on our transplantation experience in sensitized patients,19 although patients’ PRA levels were higher than normal, we believe that preexisting antibodies are not the major cause of antibody-mediated rejection. Rather, we think that blockage of new antibody production is the key to successful renal transplantation. We therefore used solely anti-CD20 antibody induction therapy in patients and obtained good clinical efficacy. Our results are similar to reports conducted overseas.20

The use of RTX and antithymocyte globulin therapies is likely to increase the risk for infection and malignant tumors in transplant recipients.21 In our study, no infections occurred during the perioperative period in all patients, which may be related to our effective postoperative measures to prevent infection. However, this risk needs to be further verified.

Although desensitization treatment enables successful renal transplantation in some sensitized patients, rejection has been reported to occur in nearly 90% of patients with PRA >80% within the first 3 months after surgery.22 Acute antibody-mediated rejection (AMR) is an important cause of graft failure. RTX is also effective for the treatment of AMR. Becker et al23 reported the use of a single dose of RTX (375 mg/m2) for the treatment of refractory acute rejection in 27 sensitized patients (PRA (35.7±10.2)%) who had failed to respond to high-dose steroid hormone treatment and combined treatment with PP and ATG, with a marked clinical efficacy. However, very few similar studies have been conducted in China.

In summary, this short-term postoperative results of renal transplantation indicate that renal transplantation was successful in highly sensitized patients who underwent RTX treatment. RTX therapy is a safe and effective approach to reduce humoral rejection. However, it is still unclear whether multiple doses of RTX would be more effective in reducing or removing antibodies than a single dose. Therefore, further explorations on the optimal dosage, treatment duration, as well as the long-term prognosis of RTX induction therapy are warranted in future studies.

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REFERENCES

1. Zachary AA, Montgomery RA, Ratner LE, Samaniego-Picota M, Haas M, Kopchaliiska D, et al. Specific and durable elimination of antibody to donor HLA antigens in renaltransplant patients. Transplantation 2003; 76: 1519-1525.
2. Katzlneson S, Bhaduri S, Cecka JM. Clinical aspects of sensitization. Clin Transpl 1997; 285-296.
3. Jordan SC, Tyan D, Stablein D, McIntosh M, Rose S, Vo A, et al. Evaluation of intravenous immunoglobulin as an agent to lower allosensitization and improve transplantation in highly sensitized adult patients with end-stage renal disease: report of the NIH IG02 trial. J Am Soc Nephrol 2004; 15: 3256-3262.
4. Montgomery RA, Cooper M, Kraus E, Rabb H, Samaniego M, Simpkins CE, et al. Renal transplantation at the Johns Hopkins Comprehensive Transplant Center. Clin Transpl 2003; 199-213.
5. Lorenz M, Regele H, Schillinger M, Kletzmayr J, Haidbauer B, Derfler K, et al. Peritransplant immunoadsorption: a strategy enabling transplantation in highly sensitized crossmatch-positive cadaveric kidney allograft recipients. Transplantation 2005; 79: 696-701.
6. Pescovitz MD, Book BK, Henson S, Leapman SB, Milgrom ML, Kimball J, et al. The addition of sirolimus to cyclosporine and steroids inhibits the anti-equine antibody response in renal transplant recipients treated with antithymocyte globulin. Am J Transplant 2003; 3: 497-500.
7. Lederer SR, Friedrich N, Banas B, Welser G, Albert ED, Sitter T. Effects of mycophenolate mofetil on donor-specific antibody formation in renal transplantation. Clin Transplant 2005; 19: 168-174.
8. Jackson AM, Zachary AA. The problem of transplanting the sensitized patient: whose problem is it? Front Biosci 2008; 13: 1396-1412.
9. Moore SB, Sterioff S, Pierides AM, Watts SK, Ruud CM. Transfusion-induced alloimmunization in patients awaiting renal allografts. Vox Sang 1984; 47: 354-361.
10. Cai J, Terasaki PI. Humoral theory of transplantation: mechanism, prevention, and treatment. Hum Immunol 2005; 66: 334-342.
11. Ernst JA, Li H, Kim HS, Nakamura GR, Yansura DG, Vandlen RL. Isolation and characterization of the B-cell marker CD20. Biochemistry 2005; 44: 15150-15158.
12. Cragg MS, Walshe CA, Ivanov AO, Glennie MJ. The biology of CD20 and its potential as a target for mAb therapy. Curr Dir Autoimmun 2005; 8: 140-174.
13. Reff ME, Carner K, Chambers KS, Chinn PC, Leonard JE, Raab R, et al. Depletion of B cells in vivo by a chimeric mouse human monoclonal antibody to CD20. Blood 1994; 83: 435-445.
14. Piro LD, White CA, Grillo-López AJ, Janakiraman N, Saven A, Beck TM, et al. Extended rituximab (anti-CD20 monoclonal antibody) therapy for relapsed or refractory low-grade or follicular non-Hodgkin's lymphoma. Ann Oncol 1999; 10: 655-661.
15. Pescovitz MD, Book BK, Henson S, Leapman SB, Milgrom ML, Kimball J, et al. The addition of sirolimus to cyclosporine and steroids inhibits the anti-equine antibody response in renal transplant recipients treated with antithymocyte globulin. Am J Transplant 2003; 3: 497-500.
16. Amante AJ, Ejercito R. Management of highly sensitized patients: Capitol Medical Center experience. Transplant Proc 2008; 40: 2274-2280.
17. Genberg H, Hansson A, Wernerson A, Wennberg L, Tydén G., Pharmacodynamics of rituximab in kidney allotransplantation. Am J Transplant 2006; 6: 2418-2428.
18. Vo AA, Lukovsky M, Toyoda M, Wang J, Reinsmoen NL, Lai CH, et al. Rituximab and intravenous immune globulin for desensitization during renal transplantation. N Engl J Med 2008; 359: 242-251.
19. Yin H, Hu XP, Li XB, Liu H, Wang W, Ren L, et al. Protein A immunoadsorption combined with rituximab in highly sensitized kidney transplant recipients. Chin Med J 2009; 122: 2752-2756.
20. Munoz AS, Rioveros AA, Cabanayan-Casasola CB, Danguilan RA, Ona ET. Rituximab in highly sensitized kidney transplant recipients. Transplant Proc 2008; 40: 2218-2221.
21. Zhang XD, Hu XP, Yin H, Wang W, Zhang X, Ma LL, et al. Aspergillus pneumonia in renal transplant recipients. Chin Med J 2008; 121: 791-794.
22. Stegall MD, Gloor J, Winters JL, Moore SB, Degoey S. A comparison of plasmapheresis versus high-dose IVIG desensitization in renal allograft recipients with high levels of donor specific alloantibody. Am J Transplant 2006; 6: 346-351.
23. Becker YT, Becker BN, Pirsch JD, Sollinger HW. Rituximab as treatment for refractory kidney transplant rejection. Am J Transplant 2004; 4: 996-1001.
Keywords:

kidney transplant; highly sensitized; rituximab

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