[Diagnosis and treatment for aplastic anemia].

Treatments of aplastic anemia comprise supportive therapy and aplastic anemia-specific therapy to recover from hematopoiesis. Supportive therapy includes transfusion, granulocyte colony-stimulating factor, and iron chelation therapy in addition to symptomatic treatment. Aplastic anemia-specific treatments that aim to achieve hematopoietic recovery are immunosuppressive therapy, thrombopoietin receptor agonist (TPO-RA) treatment, allogeneic hematopoietic stem cell transplantation, and anabolic hormone therapy. Although the transplantation achieves complete recovery of hematopoiesis (healing), there is a risk of death from transplant-related complications. The most effective drug therapy is the combination of TPO-RA and the immunotherapy combined with anti-thymocyte globulin and cyclosporine. This treatment is also effective against secondary, drug-induced, or hepatitis-associated aplastic anemia. In the treatment of aplastic anemia, the treatment choice is made based on the disease severity and patient ages.

Impact of anti-thymocyte globulin dose for graft-versus-host disease prophylaxis in allogeneic hematopoietic cell transplantation from matched unrelated donors: a multicenter experience.

Despite the widespread use of rabbit anti-thymocyte globulin (ATG) to prevent acute and chronic graft-versus-host disease (aGVHD, cGVHD) after allogeneic hematopoietic cell transplantation (allo-HCT), convincing evidence about an optimal dose is lacking. We retrospectively evaluated the clinical impact of two different ATG doses (5 vs 6-7.5 mg/kg) in 395 adult patients undergoing HSCT from matched unrelated donors (MUD) at 3 Italian centers. Cumulative incidence of aGVHD and moderate-severe cGVHD did not differ in the 2 groups. We observed a trend toward prolonged overall survival (OS) and disease-free survival (DFS) with lower ATG dose (5-year OS and DFS 56.6% vs. 46.3%, p=0.052, and 46.8% vs. 38.6%, p=0.051, respectively) and no differences in relapse incidence and non-relapse mortality. However, a significantly increased infection-related mortality (IRM) was observed in patients who received a higher ATG dose (16.7% vs. 8.8% in the lower ATG group, p=0.019). Besides, graft and relapse-free survival (GRFS) was superior in the lower ATG group (5-year GRFS 43.1% vs. 32.4%, p=0.014). The negative impact of higher ATG dose on IRM and GRFS was confirmed by multivariate analysis. Our results suggest that ATG doses higher than 5 mg/kg are not required for MUD allo-HCT and seem associated with worse outcomes.

Anti-Thymocyte Globulin Treatment Augments 1,25-Dihydroxyvitamin D3 Serum Levels in Patients Undergoing Hematopoietic Stem Cell Transplantation.

Application of anti-thymocyte globulin (ATG) is a widely used strategy for the prevention of graft-versus-host disease (GvHD). As vitamin D3 serum levels are also discussed to affect hematopoietic stem cell transplantation (HSCT) outcome and GvHD development, we analysed a possible interplay between ATG treatment and serum levels of 25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 in 4 HSCT cohorts with different vitamin D3 supplementation. ATG is significantly associated with higher serum level of 1,25-dihydroxyvitamin D3 around HSCT (day -2 to 7, peri-transplant), however only in patients with adequate levels of its precursor 25-hydroxyvitamin D3. ATG exposure had no impact on overall survival in patients supplemented with high dose vitamin D3, but was associated with higher risk of one-year treatment-related mortality (log rank test p=0.041) in patients with no/low vitamin D3 supplementation. However, the difference failed to reach significance applying a Cox-model regression without and with adjustment for baseline risk factors (unadjusted P=0,058, adjusted p=0,139). To shed some light on underlying mechanisms, we investigated the impact of ATG on 1,25-Dihydroxyvitamin D3 production by human dendritic cells (DCs) in vitro. ATG increased gene expression of CYP27B1, the enzyme responsible for the conversion of 25-hydroxyvitamin D3 into 1,25-dihydroxyvitamin D3, which was accompanied by higher 1,25-dihydroxyvitamin D3 levels in ATG-treated DC culture supernatants. Our data demonstrate a cooperative effect of 25-hydroxyvitamin D3 and ATG in the regulation of 1,25-dihydroxyvitamin D3 production. This finding may be of importance in the context of HSCT, where early high levels of 1,25-dihydroxyvitamin D3 levels have been shown to be predictive for lower transplant related mortality and suggest that vitamin D3 supplementation may especially be important in patients receiving ATG for GvHD prophylaxis.

Post-transplant cyclophosphamide versus antithymocyte globulin in patients with acute myeloid leukemia in first complete remission undergoing allogeneic stem cell transplantation from 10/10 HLA-matched unrelated donors.

BACKGROUND: Graft-versus-host disease (GVHD) remains a major contributor to mortality and morbidity after allogeneic stem-cell transplantation (allo-HSCT). The updated recommendations suggest that rabbit antithymocyte globulin or anti-T-lymphocyte globulin (ATG) should be used for GVHD prophylaxis in patients undergoing matched-unrelated donor (MUD) allo-HSCT. More recently, using post-transplant cyclophosphamide (PTCY) in the haploidentical setting has resulted in low incidences of both acute (aGVHD) and chronic GVHD (cGVHD). Therefore, the aim of our study was to compare GVHD prophylaxis using either PTCY or ATG in patients with acute myeloid leukemia (AML) who underwent allo-HSCT in first remission (CR1) from a 10/10 HLA-MUD. METHODS: Overall, 174 and 1452 patients from the EBMT registry receiving PTCY and ATG were included. Cumulative incidence of aGVHD and cGVHD, leukemia-free survival, overall survival, non-relapse mortality, cumulative incidence of relapse, and refined GVHD-free, relapse-free survival were compared between the 2 groups. Propensity score matching was also performed in order to confirm the results of the main analysis RESULTS: No statistical difference between the PTCY and ATG groups was observed for the incidence of grade II-IV aGVHD. The same held true for the incidence of cGVHD and for extensive cGVHD. In univariate and multivariate analyses, no statistical differences were observed for all other transplant outcomes. These results were also confirmed using matched-pair analysis. CONCLUSION: These results highlight that, in the10/10 HLA-MUD setting, the use of PTCY for GVHD prophylaxis may provide similar outcomes to those obtained with ATG in patients with AML in CR1.

Current Treatment Patterns of Aplastic Anemia in China: A Prospective Cohort Registry Study.

Aplastic anemia (AA) is a hematologic disease characterized by pancytopenia and hypocellular bone marrow, potentially leading to chronic anemia, hemorrhage, and infection. The China Aplastic Anemia Committee and British Committee for Standards in Haematology guidelines recommend hematopoietic stem-cell transplantation (HSCT) or immunosuppressive therapy (IST) comprising antithymocyte globulin (ATG) with cyclosporine (CsA) as initial treatment for AA patients. With limited epidemiological data on the clinical management of AA in Asia, a prospective cohort registry study involving 22 AA treatment centers in China was conducted to describe the disease characteristics of newly diagnosed AA patients and investigate real-world treatment patterns and patient outcomes. Of 340 AA patients, 72.9, 12.6, and 3.5% were receiving IST, traditional Chinese medicine, and HSCT, respectively, at baseline; only 22.2% of IST-treated patients received guideline-recommended ATG with CsA initially. Almost all patients received supportive care (95.6%) as blood transfusion (97.8%), antibiotics (63.7%), and/or hematopoietic growth factors (58.2%). Overall, 64.8% achieved a partial or complete response, and 0.9% experienced relapse. No new safety concerns were identified; serious adverse events were largely unrelated to the treatment regimen. These results demonstrate the need to identify and minimize treatment barriers to standardize and align AA management in China with treatment guideline recommendations and further improve patient outcomes.

Impacts of thymoglobulin in patients with acute leukemia in remission undergoing allogeneic HSCT from different donors.

Antithymocyte globulin (ATG) is widely used to reduce acute graft-versus-host disease (aGVHD) and chronic GVHD (cGVHD). To clarify the different impacts of ATG for conditioning across different donor types, we retrospectively analyzed patients with acute leukemia (n = 6617) who underwent hematopoietic stem cell transplantation between 2008 and 2015 with ATG (n = 279) or without ATG (n = 6338). Because thymoglobulin is the only ATG drug approved for GVHD prophylaxis in Japan since September 2008, we included thymoglobulin alone in the present analysis. The survivors' median follow-up time was 1081 days. Patients were categorized into 5 groups: cord blood (CB; n = 1915), matched related donor (n = 1772), 1-antigen mismatched related donor (1-MMRD; n = 225), matched unrelated donor (MUD; n = 1742), and 1-allele mismatched unrelated donor (1-MMUD; n = 963). In multivariate analysis, ATG decreased overall survival (hazard ratio [HR], 1.403; P = .054) and GVHD-free/relapse-free survival (GRFS) (HR, 1.458; P = .053) in association with increased nonrelapse mortality (NRM) (HR, 1.608; P =03) with CB, whereas it improved GRFS (HR, 0.515; P < .01) and decreased grades II to IV aGVHD (HR, 0.576; P < .01), extensive cGVHD (HR, 0.460; P = .02), and NRM (HR, 0.545; P = .03) with 1-MMUD. ATG did not impact survival with 1-MMRD and MUD. The use of ATG in conditioning is beneficial due to the reduction in acute/chronic GVHD without increasing NRM or disease relapse only in 1-MMUD transplantation. On the other hand, ATG is not recommended for CB transplantation.

[Significance of HLA 1-locus mismatch and ATG administration in unrelated hematopoietic stem cell transplantation].

HLA 1-locus-mismatched unrelated donors (1MMUD) are used in allogeneic hematopoietic stem cell transplantation (allo-HCT) for patients who lack an HLA-matched donor. Here we retrospectively reviewed 3,313 patients with acute leukemia or myelodysplastic syndrome who underwent bone marrow transplantation from an HLA allele-matched unrelated donor (MUD) or 1MMUD in 2009-2014. We compared the outcomes of MUD (n＝2,089) and 1MMUD with antithymocyte globulin [ATG; 1MM-ATG (＋) ; n＝109] with those of 1MMUD without ATG [1MM-ATG (-) ; n＝1,115]. In the 1MM-ATG (＋) group, the median total dose of ATG (thymoglobulin) was 2.5 (range, 1.0-11.0) mg/kg. The rates of grade III-IV acute GvHD, non-relapse mortality (NRM), and overall mortality were significantly lower in the MUD group than in the 1MM-ATG (-) group [hazard ratio (HR) 0.77; P＝0.016; HR, 0.74, P<0.001; and HR, 0.87, P＝0.020, respectively]. Similarly, the rates of grade III-IV acute GvHD, NRM, and overall mortality were significantly lower in the 1MM-ATG (＋) group than in the 1MM-ATG (-) group (HR, 0.42, P＝0.035; HR, 0.35, P<0.001; and HR, 0.71, P＝0.042, respectively). Even in the recent cohort, the outcome of allo-HCT from 1MM-ATG (-) was inferior to that of allo-HCT from MUD. Nevertheless, the negative impact of 1MMUD disappeared with the use of low-dose ATG without exacerbating the risk of relapse.

Resistant Cytomegalovirus Infection After Renal Transplantation: Literature Review.

BACKGROUND: Resistant cytomegalovirus (R-CMV) is an emerging problem in the renal transplantation population. The most frequent CMVs are high-resistance mutations (UL97 gene). METHODS: We describe our experience in management of R-CMV after renal transplant at our center (2012-2016). RESULTS: We encountered 3 cases of R-CMV infection after renal transplant (all primary infections). All 3 patients received induction therapy with corticosteroids, tacrolimus, and mycophenolate mofetil. The first patient (basiliximab induction, preemptive CMV) developed CMV replication on day +53, which responded poorly both to standard-dose valganciclovir (vGCV) and high-dose ganciclovir (GCV) (creatinine clearance [CrCl] >70 mL/min; vGCV 900 mg twice daily for 50 days and GCV 7.5 mg/kg twice daily for 8 days). Hematologic toxicity occurred. The R-CMV test was positive and foscarnet (FOS) was initiated (90 mg/kg twice daily for 21 days). The second patient presented CMV infection (day +30, thymoglobulin induction, CMV prophylaxis), which was not controlled with the high dose (CrCl 23 mL/min; GCV 3.5 mg/kg twice daily and vGCV 900 mg twice daily), resulting in severe neutropenia. R-CMV was detected and FOS initiated (FOS 50 mg/kg twice daily for 7 days and 50 mg/kg every 2 days for 13 days). The third patient's infection occurred on day +22 (basiliximab induction, preemptive CMV). Standard-dose vGCV was uneffective (CrCl >70 mL/min, vGCV 900 mg twice daily) and it did not respond to the high dose (GCV 7.5 mg/kg twice daily and vGCV 2700 mg/d). Moderate hematologic toxicity occurred. R-CMV was diagnosed and FOS treatment begun (FOS 70 mg/kg per day for 2 weeks). CONCLUSIONS: Resistant CMV infection may be severe due to viral infection and side effects of high-dose antiviral treatment. We presented 3 cases requiring the use of FOS in the absence of response or toxic effects from the usual treatment, with an optimal sustained response (temporary in case 2) and without serious side effects.

Allogeneic/Matched Related Transplantation for ß-Thalassemia and Sickle Cell Anemia.

Allogeneic hematopoietic stem cell transplantation (HSCT) can cure single gene disorders such as thalassemia and sickle cell anemia (SCA). These non-malignant diseases have in common severe hemolytic anemia and high proliferative bone marrow, requiring frequent transfusions. The risk of rejection is high and graft-vs-host disease is not desirable. Important progress has been made in the management of these diseases, including leukocyte depletion of blood products, and chelation therapy, for both diseases, and erythrocytapheresis and hydroxycarbamide for SCA. However, morbidity and quality of life are still of concern. Results have also significantly improved for HSCT, with the reduction of rejection by using anti-thymocyte globulin (ATG), which also decreases the risk of chronic graft-vs-host disease. Current data show a more than 90% chance of cure with myeloablative conditioning in children with hemoglobinopathy and a geno-identical donor. Results are similar whether the cell source is cord blood or bone marrow. Because of the risk of conditioning-related infertility, ovarian and/or testis cryopreservation should be discussed. Non-myeloablative conditioning regimens have also been successfully developed in adults with SCA and organ dysfunction, making cure possible. These encouraging results should incite to perform HLA typing early in families with hemoglobinopathies, and to systematically propose sibling cord blood cryopreservation for those without geno-identical donor.

[Biotherapy targeting the immune system]. / Biothérapies ciblant le systéme immunitaire.

The use of monoclonal antibody targeted therapy has changed the management of several diseases, including in hematology and immunology. The panel of the present available biotherapies allows a specific action at various stages of the immune response. Indeed, some of these molecules can target the naive T cell at the immunological synapse or the way of TH1, TH17 and regulatory T cell. Others may be more specific for the B cell and immunoglobulin. Some will even be active on both B and T cells.

Comparison of rabbit antithymocyte globulin and Jurkat cell-reactive anti-T lymphocyte globulin as a first-line treatment for children with aplastic anemia.

The purpose of this study was to investigate the effects of rabbit antihuman thymocyte globulin (R-ATG) and Jurkat cell-reactive anti-T lymphocyte globulin (ATG-F) in the treatment of childhood aplastic anemia (AA) and compare their efficacy and side effects. A total of 53 children with AA were analyzed in the present study, including 32 cases of severe AA, 10 cases of very severe AA and 11 cases of transfusion-dependent nonsevere AA. While receiving immunosuppressive therapy (IST), 29 and 24 patients, all of whom received long-term oral supplement with cyclosporin A (CSA), androgen, and traditional Chinese medicines, were treated with R-ATG and ATG-F, respectively. If necessary, the patients were also given supportive care such as component transfusion and/or infection control. Absolute counts of peripheral blood lymphocyte at various time points were dynamically measured after ATG therapy. According to the International AA Treatment and Effect standards, we found that there were no statistically significant differences in the response rate (70.83% vs. 68.97%, p > 0.05) and the overall survive rate (83.33% vs. 82.76%, p > 0.05) between the ATG-F and R-ATG groups. In addition, no obvious differences were observed between these two groups in the response time, efficacy in severe AA and very severe AA, or the incidence rates of ATG-related adverse reactions. After ATG treatment, the extent of peripheral blood lymphocyte reduction and duration in peripheral blood were similar between the ATG-F and R-ATG groups. The results of this study showed that ATG-F and R-ATG had similar efficacy and adverse reactions in the first-line treatment of childhood AA, despite being derived from different immunogens.

Retrospective study of alemtuzumab vs ATG-based conditioning without irradiation for unrelated and matched sibling donor transplants in acquired severe aplastic anemia: a study from the British Society for Blood and Marrow Transplantation.

This retrospective national study compared the use of alemtuzumab-based conditioning regimens for hematopoietic SCT (HSCT) in acquired severe aplastic anemia with antithymocyte globulin (ATG)-based regimens. One hundred patients received alemtuzumab and 55 ATG-based regimens. A matched sibling donor (MSD) was used in 87 (56%), matched unrelated donor (MUD) in 60 (39%) and other related or mismatched unrelated donor (UD) in 8 (5%) patients. Engraftment failure occurred in 9% of the alemtuzumab group and 11% of the ATG group. Five-year OS was 90% for the alemtuzumab and 79% for the ATG groups, P=0.11. For UD HSCT, OS of patients was better when using alemtuzumab (88%) compared with ATG (57%), P=0.026, although smaller numbers of patients received ATG. Similar outcomes for MSD HSCT using alemtuzumab or ATG were seen (91% vs 85%, respectively, P=0.562). A lower risk of chronic GVHD (cGVHD) was observed in the alemtuzumab group (11% vs 26%, P=0.031). On multivariate analysis, use of BM as stem cell source was associated with better OS and EFS, and less acute and cGVHD; young age was associated with better EFS and lower risk of graft failure. This large study confirms successful avoidance of irradiation in the conditioning regimens for MUD HSCT patients.

Impact of enterococcal colonization and infection in solid organ transplantation recipients from the Swiss transplant cohort study.

BACKGROUND: The burden of enterococcal infections has increased over the last decades with vancomycin-resistant enterococci (VRE) being a major health problem. Solid organ transplantation is considered as a risk factor. However, little is known about the relevance of enterococci in solid organ transplantation recipients in areas with a low VRE prevalence. METHODS: We examined the epidemiology of enterococcal events in patients followed in the Swiss Transplant Cohort Study between May 2008 and September 2011 and analyzed risk factors for infection, aminopenicillin resistance, treatment, and outcome. RESULTS: Of the 1234 patients, 255 (20.7%) suffered from 392 enterococcal events (185 [47.2%] infections, 205 [52.3%] colonizations, and 2 events with missing clinical information). Only 2 isolates were VRE. The highest infection rates were found early after liver transplantation (0.24/person-year) consisting in 58.6% of Enterococcus faecium. The highest colonization rates were documented in lung transplant recipients (0.33/person-year), with 46.5% E. faecium. Age, prophylaxis with a betalactam antibiotic, and liver transplantation were significantly associated with infection. Previous antibiotic treatment, intensive care unit stay, and lung transplantation were associated with aminopenicillin resistance. Only 4/205 (2%) colonization events led to an infection. Adequate treatment did not affect microbiological clearance rates. Overall mortality was 8%; no deaths were attributable to enterococcal events. CONCLUSIONS: Enterococcal colonizations and infections are frequent in transplant recipients. Progression from colonization to infection is rare. Therefore, antibiotic treatment should be used restrictively in colonization. No increased mortality because of enterococcal infection was noted.

A conditioning platform based on fludarabine, busulfan, and 2 days of rabbit antithymocyte globulin results in promising results in patients undergoing allogeneic transplantation from both matched and mismatched unrelated donor.

Conditioning regimen including fludarabine, intravenous busulfan (Bx), and 5 mg/kg total dose of rabbit antithymocyte globulin (r-ATG) (FBx-ATG) results in low incidence of graft-versus-host disease (GVHD) and non-relapse mortality (NRM) after allogeneic hematopoietic stem cell transplantation (Allo-HSCT) from HLA-matched related or unrelated donors (MUD). However, whether this platform produces similar results in the setting of one mismatch unrelated donor (MMUD) Allo-HSCT is not known. We retrospectively analyzed patients aged less than 65 years who were diagnosed with hematological malignancies and received FBx-ATG regimen prior to Allo-HSCT from MUD (N = 74) or MMUD (N = 40). We compared outcome of MUD versus MMUD patients. There was no difference in the cumulative incidence of grades II-IV acute GVHD (MUD: 34% vs. MMUD: 35%, P = 0.918), but MMUD patients developed more grade III-IV acute GVHD (MUD: 5% vs. MMUD: 15%, P = 0.016). The cumulative incidences of overall chronic GVHD (MUD: 33% vs. MMUD: 22%, P = 0.088) and extensive chronic GVHD (MUD: 20% vs. MMUD: 19%, P = 0.594) were comparable. One-year NRM was similar in both groups (MUD: 16% vs. MMUD: 14%, P = 0.292); similarly, progression-free survival (MUD: 59% vs. MMUD: 55%, P = 0.476) and overall survival (MUD: 63% vs. MMUD: 61%, P = 0.762) were not different between both groups. With a median follow up of 24 months, 35 of 74 MUD patients (47%) and 19 of 40 MMUD patients (48%) were free of both disease progression and immunosuppressive treatment. We conclude that the FBx-ATG regimen results in low incidences of NRM and GVHD in both MUD and the MMUD recipients.

[Hematologic improvement with deferasirox following tandem antithymocyte globulin treatment in a transfusion-dependent patient with severe aplastic anemia].

A 62-year-old man with transfusion-dependent severe aplastic anemia received immunosuppressive therapy (IST) with rabbit antithymocyte globulin and cyclosporine A in April 2010. However, his transfusion dependency did not improve. As more than 100 red blood cell (RBC) transfusions had been performed, he was administered iron chelation therapy (ICT) with deferasirox (DFX) to improve iron overload starting in July 2011. Consequently, both RBC and platelet transfusion dependency gradually improved concomitant with a decrease in serum ferritin. The bone marrow (BM) biopsy findings before administration of DFX showed severe iron accumulation and strong positive immunostaining for 8-OHdG, a marker of oxidative stress due to free iron. One year after ICT, the number of BM hematopoietic cells was increased and both iron deposition and oxidative stress were decreased. These findings suggest that DFX may contribute to hematological improvement in patients with IST-refractory aplastic anemia.

Unexpected death: anaphylactic intraoperative death due to Thymoglobulin carbohydrate excipient.

Anaphylactic shock is a life-threatening allergic response characterized by severe hypotension, inducing tissue hypoperfusion with possible multi-organ failure and death. We describe the first case of fatal intra-operative anaphylactic shock due to prolonged infusion of Thymoglobulin during Orthotopic Liver Transplantation (OLT), resulting from recruitment of both mastocytes and basophils, activated and degranulated. Post-mortem serological analysis on a preserved, pre-OLT sample of the patient's blood revealed specific IgE against carbohydrate cross-reactive determinants (CCDs), such as MUXF3 and nAna c2, proving that anaphylactic reaction was triggered by the Thymoglobulin carbohydrate excipient (sugar alcohol mannitol), rather than anti-thymocyte globulin itself. Our findings are consistent with scientific data reported in the literature, where only one case of non-fatal anaphylaxis to Thymoglobulin has been described, despite the existence of proven cases of anaphylactic reaction to mannitol. This case highlights the need to pay particular attention in future not only to active substances but also to drug excipients, above all during intra-operative drug delivery. In view of the important role played by basophils in this kind of anaphylaxis, the basophil activation test (BAT) could prove useful in preventing anaphylactic death from CCDs.

Risk adopted allogeneic hematopoietic stem cell transplantation using a reduced intensity regimen for children with thalassemia major.

BACKGROUND: Patients with thalassemia in developing countries have limited access to safe transfusions, regular medical care and chelation therapy. Although allogeneic hematopoietic stem cell transplantation (HSCT) can offer a curative approach, there are limited data on the use of this procedure in developing countries. PROCEDURE: Forty-four patients underwent a risk adopted HSCT from matched related family donor in Jordan. Thirty-one patients (7 Class 1 and 24 Class 2) underwent myeloablative conditioning (MAC) with busulfan (16 mg/kg), cyclophosphamide (200 mg/kg) and antithymocyte globulin (ATG). Thirteen patients all with Class 3, seven with hepatitis C received reduced intensity conditioning (RIC) with busulfan (8 mg/kg), fludarabine (175 mg/m(2)), total lymphoid irradiation (500 cGy) and ATG. RESULTS: All patients had initial neutrophil and platelet engraftment. Secondary graft failure was observed in 2 (6%) patients receiving myeloablative HSCT and 3 (23%) patients receiving RIC. At a median follow up of 64 months (13-108), 43 of 44 patients are alive. The 5-year probability of overall survival (OS) was 97.8% for all patients, 96.8% for patients received MAC and 100% for patients received RIC. The 5-year probability of thalassemia-free survival was 86.4% for all patients, 90.3% and 77% for patients who received MAC and RIC, respectively. CONCLUSION: Implementing a risk-adopted therapy in patient with thalassemia in Jordan can result in an excellent thalassemia free and OS, especially in those at highest risk.

Rapid activation of monocyte tissue factor by antithymocyte globulin is dependent on complement and protein disulfide isomerase.

Lymphocyte depletion with antithymocyte globulin (ATG) can be complicated by systemic coagulation activation. We found that ATG activated tissue factor procoagulant activity (TF PCA) on monocytic cells more potently than other stimuli that decrypt TF, including cell disruption, TF pathway inhibitor inhibition, and calcium ionophore treatment. Induction of TF PCA by ATG was dependent on lipid raft integrity and complement activation. We showed that ATG-mediated TF activation required complement activation until assembly of the C5b-7 membrane insertion complex, but not lytic pore formation by the membrane attack complex C5b-9. Consistently, induction of TF PCA by ATG did not require maximal phosphatidylserine membrane exposure and was not correlated with the magnitude of complement-induced lytic cell injury. Blockade of free thiols, an inhibitory monoclonal antibody to protein disulfide isomerase (PDI), and the small-molecule PDI antagonist quercetin-3-rutinoside prevented ATG-mediated TF activation, and C5 complement activation resulted in oxidation of cell surface PDI. This rapid and potent mechanism of cellular TF activation represents a novel connection between the complement system and cell surface PDI-mediated thiol-disulfide exchange. Delineation of this clinically relevant mechanism of activation of the extrinsic coagulation pathway during immunosuppressive therapy with ATG may have broader implications for vascular thrombosis associated with inflammatory disorders.

Rapid and complete reconstitution of autologous haemopoiesis after cord blood infusion in treatment-naive patients with severe aplastic anemia receiving high-dose cyclophosphamide/ATG therapy.

UNLABELLED: Although high-dose cyclophosphamide seems to achieve durable complete remission, there are still concerns about its too much early toxicity. So, we designed a clinical study to investigate the effects of high-dose cyclophosphamide/ATG combined with cord blood infusion as first-line therapy for patients with severe aplastic anemia. PATIENTS AND METHOD: Between January 2003 and September 2007, we treated 16 treatment-naive patients with severe aplastic anemia with cord blood infusion after high-dose cyclophosphamide (50 mg/kg/d × 2) and rabbit antithymocyte globulin (3 mg/kg/d × 5) therapy. RESULTS: Although only one patient had durable full donor engraftment, 14 of the enrolled 16 patients had rapid autologous hematopoietic recovery. The median recovery time for neutrophils and platelets was only 23 and 37 d after infusion of cord blood. Of the 15 responding patients, all patients achieved treatment-free remission: nine patients met the criteria for a complete remission; six patients achieved a partial remission. CONCLUSION: Infusion of cord blood after high-dose cyclophosphamide/ATG resulted in a rapid autologous hematologic recovery and a high response rate in patients with treatment-naive patients with severe aplastic anemia. These promising results merit further investigation and confirmation on a larger number of patients.