Regeneration of peripheral blood cells following ABO incompatible allogeneic bone marrow transplantation for severe aplastic anaemia

Pure red-cell aplasia following major and bi-directional ABO-incompatible allogeneic stem-cell transplantation: recovery of donor-derived erythropoiesis after long-term treatment using different therapeutic strategies

Blood group incompatibility between donor and recipient of allogeneic stem cell transplants may be associated with post-transplant erythroid aplasia. A total of 548 patients (pts) received allogeneic transplant for malignant and non-malignant hematologic disorders. In a retrospective analysis, the prevalence and outcome of pure red-cell aplasia (PRCA) in 44 pts with major and bi-directional ABO-mismatch were investigated. Bone marrow grafts were major ABO incompatible in 30 pts; there was bi-directional mismatch in the remaining 14 pts. The median number of transplanted mononuclear cells (NC) was 4.74 x 10(8)/kg (range 0.1-26.4) including CD34+ cells, 3.02 x 10(6)/kg (range 0.9-21.7). Granulocyte engraftment >0.5 x 10e9/l occurred after a median of 21 days (7-32), and platelet exceeded >50 x 10e9/l after a median of 23.5 days (12-109). Acute and chronic graft vs host disease (GVHD) developed in 23 (52%) and 26 (59%) of the patients, respectively. Six (13%) patients transplanted with major and bi-directional ABO-incompatibility developed PRCA. The treatment of PRCA consisted of plasmapheresis (PEX), rapid cyclosporine (CsA) discontinuation, donor lymphocyte infusions (DLI), erythropoietin (EPO), azathioprine, and rituximab. The therapy resulted in erythroid recovery in five out of six patients after a median of 13 months (range 3-16). The median number of transfused red blood cells (RBCs) was 36 U (range 8-57). With a median follow-up of 37 months, the 5-year probability of overall survival (OS) for the PRCA group was 66%. Major ABO mismatch may lead to delayed donor erythroid engraftment. It results in long-term transfusion dependence and, therefore, the risk of iron overload. The therapy is long lasting, but usually effective in majority of patients.

Lack of effect of donor–recipient ABO mismatching on outcome following allogeneic hematopoietic stem cell transplantation

Several recently published studies have suggested that patients who undergo ABO mismatched hematopoietic stem cell transplantation may be at increased risk for relapse, graft-versus-host disease, transplant-related mortality, and/or all-cause mortality. To investigate this issue further, we analyzed potential associations between the donor-recipient ABO mismatch pattern and the above outcome measures among 240 consecutive patients who underwent allogeneic hematopoietic stem cell transplantation at our institution. Our analyses uncovered no significant associations between donor-recipient ABO mismatch pattern and overall survival, event-free survival, transplant-related mortality, incidence of acute graft-versus-host disease (GVHD), or incidence of chronic GVHD. Our data do not support recent assertions that donor-recipient ABO mismatching is a major risk factor for patients undergoing allogeneic transplant, nor do they support recent assertions that ABO matching should be an important consideration in selecting allogeneic hematopoietic stem cell donors.

ABO-incompatible bone marrow transplantation: a GITMO survey of current practice in Italy and comparison with the literature

ABO incompatibility is not considered a contraindication for allogeneic haematopoietic stem cell transplantation (HSCT) despite its association with several immunohaematological complications. At present, there is no general agreement concerning the best methods to reduce these problems. To survey current practice related to ABO-incompatible HSCT in Italy, a questionnaire was sent to all GITMO centres. Specific questions were addressed for management in pretransplant, peritransplant and post transplant phases. A comparison was made with the experience reported in the literature. In all, 74% of GITMO centres answered the questionnaire. A high degree of heterogeneity concerning the pretransplant tests, methods to overcome infusion of ABO-incompatible marrow and post transplant transfusion policy and monitoring was evident. For many of these aspects the literature does not contain unanimous guidelines. The considerable degree of heterogeneity that reflects, at least partially, the lack of consensus in the literature demonstrates that ABO incompatibility is still an open issue in the setting of HSCT and that further studies are needed for a more rationale approach and for the production of evidence-based guidelines.

Resistant pure red cell aplasia after allogeneic stem cell transplantation with major ABO mismatch treated by escalating dose donor leukocyte infusion

We report a case of pure red cell aplasia (PRCA) following allogeneic stem cell transplantation (SCT) with major ABO mismatch which proved resistant to all standard treatment options such as change in immunosuppressive treatment, high-dose erythropoietin (EPO) or plasma exchange. We therefore proceeded to administer five cycles of Rituximab therapy, without success. Finally, escalating doses of donor-derived leukocyte infusion (DLI) resolved the PRCA of our patient 415 d after bone-marrow transplantation (BMT) and 140 d after the first infusion of donor leukocytes. A review of the literature shows the efficacy of various treatments; the role of DLI and other treatment options are discussed. Furthermore, the underlying pathophysiological mechanisms especially with regard to the role of NK cells in alloreactivity after allogeneic SCT are explained.

Changes of isoagglutinin titres after ABO-incompatible allogeneic stem cell transplantation

We investigated the changes in isoagglutinin titres in 62 patients who underwent ABO-incompatible allogeneic stem cell transplantation. After major [and/or (+/-) minor] ABO-incompatible transplantation, recipient-derived isoagglutinins against donor-type red blood cells (RBCs) disappeared more rapidly in unrelated recipients (P = 0.006) and in patients with acute graft-versus-host disease (GVHD, P = 0.025) than in sibling recipients and in patients without acute GVHD respectively. Pure red cell aplasia (PRCA) developed in 10 out of 35 evaluable patients who underwent major (+/- minor) ABO-incompatible transplantation, and the post-transplant increase of isoagglutinin titres was a significant predictor for the occurrence of PRCA. In five out of 36 patients who underwent minor (and/or (+/-) major) ABO-incompatible transplantation, donor-derived isoagglutinins against recipient RBCs were detectable without clinically overt haemolysis. Isoagglutinin titres against ABO antigens absent both on recipient and donor RBCs decreased during the early post-transplant period then rose subsequently in 24 out of 29 patients at (median) d 59 post transplant. Our study showed that changes in isoagglutinin titres might have clinical implications in the occurrence of immunohaematological complications such as PRCA or immune-mediated haemolysis, and might reflect immunohaematological reconstitution after transplantation. Furthermore, our data regarding time to disappearance of recipient-derived isoagglutinins against donor-type RBCs after major ABO-incompatible transplantation suggest the presence of a graft-versus-plasma cell effect.

Delayed donor red cell chimerism and pure red cell aplasia following major ABO-incompatible nonmyeloablative hematopoietic stem cell transplantation

Delayed donor red cell engraftment and pure red cell aplasia (PRCA) are well-recognized complications of major ABO-incompatible hematopoietic stem cell transplantation (SCT) performed by means of myeloablative conditioning. To evaluate these events following reduced-intensity nonmyeloablative SCT (NST), consecutive series of patients with major ABO incompatibility undergoing either NST (fludarabine/cyclophosphamide conditioning) or myeloablative SCT (cyclophosphamide/high-dose total body irradiation) were compared. Donor red blood cell (RBC) chimerism (initial detection of donor RBCs in peripheral blood) was markedly delayed following NST versus myeloablative SCT (median, 114 versus 40 days; P <.0001) and strongly correlated with decreasing host antidonor isohemagglutinin levels. Antidonor isohemagglutinins declined to clinically insignificant levels more slowly following NST than myeloablative SCT (median, 83 versus 44 days; P =.03). Donor RBC chimerism was delayed more than 100 days in 9 of 14 (64%) and PRCA occurred in 4 of 14 (29%) patients following NST, while neither event occurred in 12 patients following myeloablative SCT. Conversion to full donor myeloid chimerism following NST occurred significantly sooner in cases with, compared with cases without, PRCA (30 versus 98 days; P =.008). Cyclosporine withdrawal appeared to induce graft-mediated immune effects against recipient isohemagglutinin-producing cells, resulting in decreased antidonor isohemagglutinin levels and resolution of PRCA following NST. These data indicate that significantly delayed donor erythropoiesis is (1) common following major ABO-incompatible NST and (2) associated with prolonged persistence of host antidonor isohemagglutinins. The clinical manifestations of these events are affected by the degree and duration of residual host hematopoiesis.

Graft-versus-host disease and donor-directed hemagglutinin titers after ABO-mismatched related and unrelated marrow allografts: evidence for a graft-versus-plasma cell effect

The gradual disappearance of host antidonor isohemagglutinins after major ABO-mismatched hematopoietic stem cell (HSC) allografts has been attributed to the gradual destruction of host plasma cells by graft-versus-host effects. To corroborate this hypothesis, we retrospectively analyzed results from 383 major or major/minor ABO-mismatched unrelated and related HSC allografts performed between 1983 and 1998. All patients were conditioned by high-dose pretransplant therapy and given methotrexate/cyclosporine for graft-versus-host disease (GvHD) prophylaxis. Of the 383 patients, 155 had HLA-matched related and 228 had unrelated grafts. We asked whether unrelated recipients experienced a more rapid disappearance of isohemagglutinins than related recipients, and whether, within the groups of related and unrelated recipients, the titer disappeared faster in patients with GvHD than in those without GvHD. The median time to reach undetectable antidonor IgG and IgM titers was significantly shorter in unrelated recipients (46 versus 61 days; P = .016). In addition, related recipients with GvHD had a 2.2-fold increased likelihood (1.12-4.39,95% CI; P = .02) of reaching undetectable titers within 100 days than patients without GvHD. The persistence of antidonor isohemagglutinins led to significantly increased red blood cell (RBC) transfusion requirements in the ABO-mismatched related patients compared with ABO-matched counterparts. However, time to neutrophil and platelet engraftment, incidence of GvHD, and survival were not influenced by ABO incompatibility. In conclusion, our results corroborate the hypothesis that the rate of disappearance of antidonor isohemagglutinins after ABO-mismatched allogeneic HSC grafts is influenced by the degree of genetic disparity between donor and recipient, suggesting a graft-versus-plasma cell effect.

Graft-versus-host disease and donor-directed hemagglutinin titers after ABO-mismatched related and unrelated marrow allografts: evidence for a graft-versus-plasma cell effect

The gradual disappearance of host antidonor isohemagglutinins after major ABO-mismatched hematopoietic stem cell (HSC) allografts has been attributed to the gradual destruction of host plasma cells by graft-versus-host effects. To corroborate this hypothesis, we retrospectively analyzed results from 383 major or major/minor ABO-mismatched unrelated and related HSC allografts performed between 1983 and 1998. All patients were conditioned by high-dose pretransplant therapy and given methotrexate/cyclosporine for graft-versus-host disease (GvHD) prophylaxis. Of the 383 patients, 155 had HLA-matched related and 228 had unrelated grafts. We asked whether unrelated recipients experienced a more rapid disappearance of isohemagglutinins than related recipients, and whether, within the groups of related and unrelated recipients, the titer disappeared faster in patients with GvHD than in those without GvHD. The median time to reach undetectable antidonor IgG and IgM titers was significantly shorter in unrelated recipients (46 versus 61 days; P = .016). In addition, related recipients with GvHD had a 2.2-fold increased likelihood (1.12-4.39,95% CI; P = .02) of reaching undetectable titers within 100 days than patients without GvHD. The persistence of antidonor isohemagglutinins led to significantly increased red blood cell (RBC) transfusion requirements in the ABO-mismatched related patients compared with ABO-matched counterparts. However, time to neutrophil and platelet engraftment, incidence of GvHD, and survival were not influenced by ABO incompatibility. In conclusion, our results corroborate the hypothesis that the rate of disappearance of antidonor isohemagglutinins after ABO-mismatched allogeneic HSC grafts is influenced by the degree of genetic disparity between donor and recipient, suggesting a graft-versus-plasma cell effect.

Regeneration of erythropoiesis after related- and unrelated-donor BMT or peripheral blood HPC transplantation: a major ABO mismatch means problems

BACKGROUND

Blood group incompatibility in allogeneic BMT is common but does not appear to affect the outcome in terms of incidence of graft rejection or delayed engraftment. However, major ABO incompatibility may be associated with prolonged erythroid aplasia.

STUDY DESIGN AND METHODS

In a retrospective analysis of 286 allogeneic transplant recipients, the prevalence of prolonged erythroid aplasia, including pure RBC aplasia, was determined.

RESULTS

Patients receiving major ABO-incompatible grafts showed a significant delay in reticulocyte engraftment (median, 32 days; range, 12-347) from that in patients receiving ABO-identical (20; 10-152) or minor ABO-incompatible (21; 12-47) grafts. Pure RBC aplasia occurred in 7 (3%) of 240 evaluable recipients and was observed only in the major ABO-incompatible group (7/43, 16%). Treatment of pure RBC aplasia consisted of either plasma exchange, which resulted in a response within 16 to 68 days, or immunoadsorption, in which the response occurred between Days 119 and 204 after initiation of treatment.

CONCLUSION

Major ABO incompatibility may lead to delayed reticulocyte engraftment, resulting in prolonged transfusion dependency and increased risks of transmission of infection and iron overload. Therefore, therapeutic strategies should be taken into consideration to allow erythroid reconstitution in these patients.

Anti-A isoagglutinin as a risk factor for the development of pure red cell aplasia after major ABO-incompatible allogeneic bone marrow transplantation

Delayed erythropoiesis and pure red cell aplasia (PRCA) have been reported after major ABO-incompatible BMT. We attempted to find risk factors for the development of PRCA in 27 patients who underwent major ABO-incompatible BMT. In all patients, the donor marrow was depleted of RBCs before infusion. In 22 patients, isoagglutinins were determined until they disappeared. In eight (29.6%) out of 27 patients, bone marrow examination following BMT showed the findings of PRCA. We analyzed various clinico-pathologic risk factors and isoagglutinin type was the only significant risk factor. Patients with anti-A isoagglutinins against donor RBC developed PRCA more frequently than patients with anti-B (8/17 vs 0/9). Median days to the disappearance of isoagglutinins tended to be longer in patients with PRCA (PRCA vsnon-PRCA, 200 vs 66 days) and in cases with anti-A isoagglutinins (anti-A vsanti-B, 160 vs 51 days). Times to disappearance of isoagglutinins correlated with times to reticulocytes over 1% and initial appearance of donor type RBC (R2 = 0.708 and 0.711). In conclusion, RBC engraftment following major ABO-incompatible BMT was dependent on the disappearance of isoagglutinins against donor RBC, and anti-A isoagglutinin was a risk factor for the development of PRCA after major ABO-incompatible allogeneic BMT. Bone Marrow Transplantation (2000) 25, 179-184.

Pure red cell aplasia after major ABO-incompatible bone marrow transplantation: two case reports of treatment with recombinant human erythropoietin

A 34-year-old man with acute myelocytic leukemia (AML: MO) and a 32-year-old woman with AML: M2 developed pure red cell aplasia (PRCA) after receiving a major ABO incompatible bone marrow transplant (BMT). The first patient responded to recombinant human erythropoietin (rhEPO) therapy, while the second did not. The second patient also received methylprednisolone (m-PSL) but developed reticulocytosis and hemolysis after the administration of m-PSL. Plasmapheresis was then performed and the patient promptly recovered from hemolysis and PRCA. We conclude that close attention must be paid when treating PRCA following major ABO-incompatible BMT with rhEPO and m-PSL, as there is always the potential for massive hemolysis.

The Use of Erythropoietin in the Treatment of Post-bone Marrow Transplatation Anemia

The issue of the role of erythropoietin (Epo) in the erythroid reconstitution after bone marrow transplantation (BMT) has been addressed in several recent studies. A defective Epo production in response to anemia has been shown to occur in patients undergoing allogeneic BMT unlike in most of those subjected to an autologous rescue. The factors involved in the inadeguate Epo production in BMT are discussed, with particular attention to the role of the immunosuppressive drug cyclosporin-A, which has been shown to inhibit Epo production in both in vivo and in vitro models. The observation of defective Epo production eventually led to the development of clinical trials of recombinant human Epo (rhEpo) administration in BMT patients; the aims of these studies were to stimulate erythroid engraftment, hence reducing blood transfusion exposure. Although the number of patients studied up to now is relatively small, a benefit from rhEpo administration in terms of accelerated erythroid engraftment seems very likely, and it may also be associated with decreased transfusional needs in most treated patients. However, further studies are needed to better define indications, dosages and schedules of rhEpo in BMT patients.

Long duration of erythrocyte hypoplasia after bone marrow transplantation

Bone marrow transplantation was performed on a 15 year old girl with chronic myelogenous leukemia. The bone marrow was obtained from her younger sister, who was human leukocyte antigen haplo-identical but major ABO incompatible. As a result, the condition of pure red cell aplasia (PRCA) persisted over a long period of time. In order to overcome major ABO incompatibility, erythrocytes were eliminated from the bone marrow graft before transplantation, and methotrexate and cyclosporine (CsA) were used to prevent graft-versus-host disease (GVHD). Administration of erythropoietin proved ineffective. B19 parvovirus infection could not be detected during that time. Agglutinin titers decreased to less than fourfold in parallel with the recovery of erythrocytes. Reports on similar PRCA have been limited to cases of transplantation with ABO incompatibility and cases where CsA was administered to prevent GVHD. This suggests that ABO incompatibility and CsA might be related to the development of PRCA.

Case report: isoimmune inhibition of erythropoiesis following ABO-incompatible bone marrow transplantation

A 26-year-old ABO-O positive patient with aplastic anemia received a bone marrow transplant from his genotypically HLA identical, but ABO-A positive, brother. Engraftment of myeloid and megakaryocytic lineages occurred within 4 weeks but pure red cell aplasia and transfusion dependent anemia persisted for 160 days. The authors postulated that the failure of erythropoiesis was due to a high titer of anti-A isohemagglutinins. They tested this hypothesis with clonal cell cultures and flow cytometric analysis of ABO antigen expression by colony forming cells in vitro. During the period of prolonged red cell aplasia, the patient had normal numbers (85 +/- 12 per 10(6) cells) of circulating donor derived, burst forming units-erythroid (BFU-E). Immunophenotypic analysis of erythroid burst colonies derived from culture of the patient's bone marrow cells showed that 91 +/- 5% of 274 nucleated red cells were A-antigen positive, confirming full donor engraftment. Autologous plasma and complement added on day 1 of culture did not affect the colony growth (82.5 +/- 15 per 10(6) cells). However, when the addition of complement was delayed until day 7 of culture, there was 90% inhibition of BFU-E (7.5 +/- 5 per 10(6) cells) compared to controls (p less than 0.0004). Based on this, the authors propose a model for expression of ABO antigens during erythropoiesis, in which BFU-E do not express ABO antigens but their progeny do. The data support the hypothesis that the mechanism of prolonged pure red cell aplasia after ABO-incompatible bone marrow transplantation is complement mediated immune destruction of erythroid progenitors past the stage of BFU-E in differentiation.

Immunoadsorption for removal of anti-A and anti-B blood group antibodies in ABO-incompatible bone marrow transplantation

About 10-15 percent of all patients undergoing allogeneic bone marrow transplantation have a major ABO-incompatibility with their donors. The risk of acute hemolytic reactions due to the infusion of an incompatible donor marrow into the recipient can basically be prevented by recipient antibody depletion or by donor marrow red cell depletion. Nine patients were treated by immunoadsorption using a cartridge with chemically synthesized human blood group A and B antigen as immunoadsorbent for antibody depletion. Within a four-hour-procedure about 2-4 times the patient plasma volume could be processed, thus lowering the anti-A and -B hemagglutinins by 2 to 3 tubes. There was a tendency of better IgG removal when titers initially were high, showing a high antibody clearing capacity. There was no significant correlation between starting titer or amount of plasma volume processed and titer reduction. No decrease in titers were observed in one case. We propose repeated immunoadsorption procedures over 2-3 consecutive days before BMT. The procedure is largely safe and without serious side effects. A major advantage is the avoidance of nonautologous human blood products compared to the conventional plasma exchange. All 8 patients surviving long enough had prompt and stable engraftment of all three cell lines post BMT. No late serological complications occurred when patients were regularly monitored and in vivo adsorption was used when titers increased.

A and B blood group antigen expression on mixed colony cells and erythroid precursors: relevance for human allogeneic bone marrow transplantation

Using anti-A and anti-B blood group monoclonal antibodies and fluorescent activated cell sorting of human bone marrow, A (or B) blood group antigen was shown to be on 5.2 +/- 5.9 (mean +/- SD) % of CFU-GEMM and 12.5 +/- 19.6% of the erythroid burst forming cells (designated BFU-GEMM) as defined by the mixed colony assay, and 49.5 +/- 20% of the BFU-E and 83.5 +/- 9.9% of the CFU-E as defined by the erythroid colony assay. This antigen expression on the BFU-GEMM is consistent with the concept that erythroid bursts stimulated by leucocyte conditioned medium are less mature, and are closer in development to the pluripotent stem cell than the BFU-E. These results help to explain the delayed erythropoiesis, and perhaps impaired engraftment of all cell lineages, that may occur in some recipients of ABO incompatible bone marrow transplants with persistent and high anti-A titres.