Unrelated cord blood transplantation in pediatric patients: a report from Saudi Arabia

Cord Blood Banking and Transplantation in a National Program: Thirteen Years of Experience

BACKGROUND

The umbilical cord blood bank at the Mexican Institute of Social Security (IMSS-CBB) was established in January 2005. This lead to the development of the UCB transplantation program. Herein, we describe the experience generated during these 13 years.

STUDY DESIGN AND METHODS

Donor selection, as well as UCB collection, processing, and banking were performed under good manufacturing practices and standard operating procedures. UCB units were thawed, processed, and released for transplantation based on HLA and nucleated cell content.

RESULTS

From January 2005-December 2017, 1,298 UCB units were banked; 164 of them were released for transplantation, and 118 UCB transplants were performed. Ninety-four transplants were performed in pediatric patients and 24 in adults. Sixty percent of them corresponded to patients with leukemia, 19% were patients with marrow failure, and the rest had immunodeficiency, hemoglobinopathy, metabolic disorders, or solid tumors. Engraftment was observed in 67 patients (57% of transplanted patients) and 64% of them were still alive when writing this article. In contrast, only 13 of the 51 (25%) non-engrafting patients were alive. At the time of writing this article, the disease-free survival rate was 37%, and the overall survival rate was 47%, with survival periods of 161-3,721 days.

CONCLUSION

The IMSS UCB banking and transplantation program has had a significant impact for many IMSS patients. The hematopoietic transplantation program at our institution has benefited from the use of UCB as a source of transplantable cells.

Successful Outcome in Patients with Fanconi Anemia Undergoing T Cell-Replete Mismatched Related Donor Hematopoietic Cell Transplantation Using Reduced-Dose Cyclophosphamide Post-Transplantation

Allogeneic hematopoietic cell transplantation (HCT) has been shown to restore normal hematopoiesis in patients with Fanconi anemia (FA), with excellent results in matched related donor HCT. Outcomes of alternative donor HCT are less favorable, however. In patients without FA, several reports have documented stable engraftment and/or a low risk of graft-versus-host disease (GVHD) using unmanipulated HLA-mismatched related donors and post-HCT cyclophosphamide (PT-CY) for GVHD prophylaxis. Data on the use of this approach in patients with FA are scarce, and thus we launched a study of HLA-mismatched related donor HCT in these patient. Here we report our findings in 19 patients. The conditioning was fludarabine 30 mg/m²/day for 5 days, antithymocyte globulin 5 mg/kg/day for 4 days, and total body irradiation (total dose, 200 cGy). GVHD prophylaxis was cyclosporine and mycophenolate and reduced doses of PT-CY, 25 mg/kg, on days +3 and +5. All patients exhibited absolute neutrophil count recovery. Grade III-IV acute GVHD occurred in 3 patients, and chronic GVHD occurred in 1 patient. At a mean follow-up of 38.3 ± 5.8 months, the 5-year probability of overall survival for our patients was 89.2% ± 7.2%. The regimen was well tolerated; hemorrhagic cystitis occurred in 7 patients, and severe mucositis occurred in 5 patients. There were 2 deaths; the primary cause of death was severe GVHD in 1 patient and leukemia recurrence in the other. We conclude that in patients with FA lacking a matched related donor, the use of mismatched related HCT with low-dose PT-CY is a viable option; it is well tolerated, with a high rate of engraftment and an acceptable incidence of GVHD.

Challenges to laboratory hematology practice: Egypt perspective

Laboratory hematology is an integral part of all clinical laboratories along the extensive healthcare facilities in Egypt. The aim of this review is to portrait the laboratory hematology practice in Egypt including its unique socioeconomic background, blood disease pattern, education and training, regulatory oversight, and the related challenges. Current practice varies widely between different parts of the healthcare system in terms of the range of tests, applied techniques, workforce experience, and quality of service. The national transfusion service (NBTS) in Egypt has been recently upgraded and standardized according to the World Health Organization (WHO) guidelines. Formal postgraduate education roughly follows the British system. Laboratory hematology specialization is achieved through 2-3 years masters' degree followed by 2-4 years doctorate degree in clinical pathology with training and research in hematology. Improvement of laboratory hematology education is recently undergoing a reform as a part of the modernization of higher education policy and following the standards developed by the National Quality Assurance and Accreditation Agency (NQAAA). Accreditation of medical laboratories is recently progressing with the development of the "Egyptian Accreditation Council" (EGAC) as the sole accreditation body system and training of assessors. Current laboratory system has many challenges, some are related to the inadequate system performance, and others are unique to laboratory hematology issues. The rapid technological advances and therapeutic innovations in hematology practice call for an adapting laboratory system with continuous upgrading.

Impact of Ethnicity on Donor Search Results for Children Requiring Stem Cell Transplantation

Hematopoietic stem cell transplantation (HSCT) can be curative for children with various malignant and nonmalignant conditions. Access to suitable unrelated living donors (ULDs) or unrelated cord blood (UCB) may be limited for certain ethnic backgrounds. We therefore determined the impact of ethnicity upon donor availability in a pediatric cohort referred for allogeneic HSCT to a single Canadian transplant center. Among 252 eligible patients, 58 (23.0%) had suitable family donors. Of 161 patients with combined ULD and UCB searches, 78 (48.4%) had a suitable ULD, whereas 143 (88.8%) had suitable UCB. The probability of finding a suitable ULD differed significantly by ethnicity (P=0.007). Non-white patients were significantly less likely to have suitable ULDs (odds ratio [OR] 0.35; 95% confidence interval [CI], 0.17-0.69; P=0.003) compared with white patients but were equally likely to have suitable UCB (OR 1.02; 95% CI, 0.36-2.89; P=0.97). Although ethnic disparities exist in pediatric patients' access to ULD for HSCT, they are narrowed by the availability of international UCB registries. These findings, however, also highlight the importance of continued recruitment of individuals of non-white ethnicities to donor registries.

Cord Blood Banking in the Arab World: Current Status and Future Developments

Umbilical cord blood transplants are now used to treat numerous types of immune- and blood-related disorders and genetic diseases. Cord blood (CB) banks play an important role in these transplants by processing and storing CB units. In addition to their therapeutic potential, these banks raise ethical and regulatory questions, especially in emerging markets in the Arab world. In this article, the authors review CB banking in five countries in the region, Jordan, Saudi Arabia, Egypt, Qatar, and the United Arab Emirates, selected for their different CB banking policies and initiatives. In assessing these case studies, the authors present regional trends and issues, including religious perspectives, policies, and demographic risk factors. This research suggests strong incentives for increasing the number of CB units that are collected from and available to Arab populations. In addition, the deficit in knowledge concerning public opinion and awareness in the region should be addressed to ensure educated decision-making.

Cyclophosphamide promotes engraftment of gene-modified cells in a mouse model of Fanconi anemia without causing cytogenetic abnormalities

A major hurdle for hematopoietic stem cell (HSC) gene therapy for inherited bone marrow disorders, including Fanconi anemia (FA), is adequate engraftment of gene-modified cells. A phenotypic defect in DNA repair renders FA patients sensitive to alkylating agents such as cyclophosphamide (Cy); however, at lower doses, Cy is well tolerated in the FA transplant setting. We tested whether non-alkylating agents could replace Cy for pretransplant conditioning to enhance engraftment of FANCA gene-modified hematopoietic cells. We compared Cy preconditioning with fludarabine (Flu) or cytarabine (AraC) or no conditioning as a control in fanca ( -/- ) mutant mice receiving gene-modified bone marrow cells. Only mice conditioned with Cy exhibited appreciable engraftment of gene-modified cells by PCR and resistance to mitomycin C (MMC). Cy administration following transplantation increased gene marking levels in all animals treated, but highest gene marking and corresponding MMC resistance were observed in mice receiving Cy pre- and posttransplantation. Importantly, no cytogenetic abnormalities were observed in Cy-treated mice. We conclude that Cy is an effective and superior preparative regimen with respect to engraftment of lentivirus-transduced cells and functional correction in fanca ( -/- ) mice. Thus, appropriately dosed Cy may provide a suitable conditioning regimen for FA patients undergoing HSC gene therapy.

Current status of pediatric umbilical cord blood transplantation in Korea: a multicenter retrospective analysis of 236 cases

We report the outcome of 236 pediatric umbilical cord blood transplantations (UCBT) performed in Korea. Given that the sources of the grafts were mostly unrelated donors (n = 226; 95.8%), only the results of unrelated UCBT were included for all statistics. The most frequent primary disease was acute leukemia (n = 167). In total, 91.7% of recipients were seropositive for cytomegalovirus (CMV). The median doses of nucleated cells and CD34+ cells were 4.84 × 10(7)/kg and 2.00 × 10(5)/kg, respectively. The median times to neutrophil (>0.5 × 10(9)/L) and platelet recovery (>20 × 10(9)/L) were 18 and 45 days, respectively. Grade 2-4 acute graft-versus-host-disease (GVHD) and chronic GVHD developed in 41.1 and 36.1% of cases, respectively. Forty-five patients developed CMV disease. The 5-year overall and event-free survival were 47.5 and 36.9%, respectively. Multivariate analysis revealed that adverse factors for survival of the whole cohort were total body irradiation-based conditioning (P = 0.007), salvage transplant (P = 0.001), failure to achieve early complete chimerism (P < 0.0005), and CMV disease (P = 0.001). The outcomes of the single- and double-unit UCBT (n = 64) were similar, while double-unit recipients were heavier (P < 0.0005) and older (P < 0.0005). We conclude that double-unit UCBT is a reasonable option for older or heavier children and that the thorough surveillance of CMV infection and the development of an effective CMV therapeutic strategy may be especially important for Korean children, whose CMV seroprevalence exceeds 90%.

Hematopoietic cell transplantation for Wiskott-Aldrich syndrome: advances in biology and future directions for treatment

The Wiskott-Aldrich syndrome (WAS) is an X-linked disorder characterized by a triad of diagnostic clinical elements: immunodeficiency, eczema, and hemorrhage caused by thrombocytopenia with small-sized platelets. The formal proof that hematopoietic cell transplantation (HCT) could be used to cure WAS revealed a requirement for both immunosuppression and myelosuppression that still underlies the standard approach to curative therapy today. The current short- and long-term toxicities of HCT are the main stumbling block for the ability to cure every patient with WAS and X-linked thrombocytopenia, and much remains to be done.

Stem cell research in the Greater Middle East: the importance of establishing policy and ethics interoperability to foster international collaborations

While fossil fuel reserves have strengthened the economies of numerous countries in the Greater Middle East (GME) for decades, multiple nations within this region are now increasingly investing in internal science and engineering programs as a mechanism to develop more extensive knowledge-based economies. One of these newly pursued disciplines is stem cell research. Nations such as Saudi Arabia and Qatar have founded nascent programs while Iran, Turkey, and Israel are more established in the field. The extent to which these investments have been productive, as measured by publication quantity and impact, remains unknown. Here we assess the state of stem cell research in the GME, report on the policy and ethical considerations facing the region, and determine the impact of international research collaborations in this area. In the majority of the region, there is no legal framework regulating stem cell research. Instead, scientists often rely on religious decrees outlining acceptable practices. These guidelines do not provide the necessary structure to foster international collaborations with nations that have enacted formal laws recognized worldwide. Our results illustrate that international collaborations in the GME produce publications of greater impact despite the fact that political tensions and issues unrelated to science have the potential to dramatically hinder cross-border relationships in the region. Overall, we conclude that the national governments of countries within the GME have the unique opportunity to establish stem cell research policies which confer interoperability between nations to foster crucial international collaborations throughout the region.