Blood Stem Cell Transplantation Research Articles

Application of DEPArrayTM technology for the isolation of white blood cells from cell mixtures in chimerism analysis

After allogeneic bone marrow or blood stem cell transplantation, STR profiling is often used for monitoring chimerisms. For the evaluation reference samples taken from the patient before the transplantation and/or taken from the donor are needed. In the case described here, no reference samples were available. Reporting the chimerism based on posttransplantation samples did not yield conclusive results;therefore, white blood cells and epithelial cells obtained from a buccal swab taken from the patient were separated using DEPArray(TM) technology and STR profiling was carried out resulting in distinct reference profiles.

Novel AgoshRNA molecules for silencing of the CCR5 co-receptor for HIV-1 infection.

Allogeneic transplantation of blood stem cells from a CCR5-Δ32 homozygous donor to an HIV-infected individual, the “Berlin patient”, led to a cure. Since then there has been a search for approaches that mimic this intervention in a gene therapy setting. RNA interference (RNAi) has evolved as a powerful tool to regulate gene expression in a sequence-specific manner and can be used to inactivate the CCR5 mRNA. Short hairpin RNA (shRNA) molecules can impair CCR5 expression, but these molecules may cause unintended side effects and they will not be processed in cells that lack Dicer, such as monocytes. Dicer-independent RNAi pathways have opened opportunities for new AgoshRNA designs that rely exclusively on Ago2 for maturation. Furthermore, AgoshRNA processing yields a single active guide RNA, thus reducing off-target effects. In this study, we tested different AgoshRNA designs against CCR5. We selected AgoshRNAs that potently downregulated CCR5 expression on human T cells and peripheral blood mononuclear cells (PBMC) and that had no apparent adverse effect on T cell development as assessed in a competitive cell growth assay. CCR5 knockdown significantly protected T cells from CCR5 tropic HIV-1 infection.

Addition of rituximab to CHOP-like chemotherapy in first line treatment of primary mediastinal B-cell lymphoma

BackgroundThe addition of rituximab (R) to CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) -like therapy has improved survival in primary mediastinal B-cell lymphoma (PMBCL) patients. However, these results were obtained in young low risk patients and a reevaluation in an unselected patient cohort is warranted.MethodsIn this study, we analyzed 80 PMBCL patients treated with a CHOP-based regimen with and without rituximab.ResultsIn the non-rituximab cohort 10-year progression free survival (PFS) was 67% and 10-year overall survival (OS) was 72% versus a PFS of 95% and a OS of 92% in the rituximab group, PFS P = 0.001, OS P = 0.023. A subgroup PFS analysis by international prognostic index (IPI) risk revealed that all risk groups benefit from addition of rituximab to induction chemotherapy. In addition, OS probability was higher in the group of non-low risk patients who were treated with rituximab compared to those patients who did not receive rituximab (P = 0.035). In multivariate analysis, only addition of rituximab to induction chemotherapy and reaching complete remission (CR) after first line therapy had a beneficial effect on both PFS and OS, whereas IPI, age, upfront high dose (HD) chemotherapy/autologous blood stem cell transplantation (ABSCT) and rituximab maintenance had no impact on survival.ConclusionsOur data demonstrate a survival benefit in unselected PMBCL patients treated with CHOP-like induction regimen and additional rituximab independently of the IPI risk score.

Effect of human umbilical cord blood stem cell transplantation on oval cell response in 2-AAF/CCL4 liver injury model: experimental immunohistochemical study

BackgroundOval cells, specific liver progenitors, are activated in response to injury. The human umbilical cord blood (hUCB) is a possible source of transplantable hepatic progenitors and can be used in cases of severe liver injury. We detected the effect of hUCB stem cell transplantation on natural response of oval cells to injury.MethodsTwenty-four female albino rats were randomly divided into three groups: (A) control, (B) liver injury with hepatocyte block, and (C) hUCB transplanted group. Hepatocyte block was performed by administration of 2-acetylaminofluorene (2-AAF) for 12 days. CCL4 was administrated at day 5 from experiment start. Animals were sacrificed at 9 days post CCL4 administration, and samples were collected for biochemical and histopathological analysis. Oval cell response to injury was evaluated by the percentage of oval cells in the liver tissue and frequency of cells incorporated into new ducts.ResultsImmunohistochemical analysis of oval cell response to injury was performed. There was significant deviation in the hUCB-transplanted (4.9 ± 1.4) and liver injury groups (2.4 ± 0.9) as compared to control (0.89 ± 0.4) 9 days post injury. Detection of oval cell response was dependant on OV-6 immunoreactivity. For mere localization of cells with human origin, CD34 antihuman immunoreactivity was performed. There was no significant difference in endogenous OV-6 immunoreactivity following stem cell transplantation as compared to the liver injury group.ConclusionsIn vivo transplantation of cord blood stem cells (hUCB) does not interfere with natural oval cell response to liver injury.

Épidermolyses bulleuses héréditaires : protocole national de diagnostic et de soins (PNDS)

Hereditary epidermolysis bullosa (EB) is a heterogeneous group of rare genetic diseases characterized by fragile skin and/or mucous membrane, and it may be either local or generalized. It is caused by mutations in genes encoding different proteins involved mainly in the structure and function of the dermal-epidermal junction. Nineteen genes have so far been identified. They are classified by level of skin cleavage (from top to bottom) into four groups: EB simplex, junctional EB, dystrophic EB and Kindler syndrome. Clinically suspected diagnosis is confirmed by immunohistochemical examination of a skin biopsy at specialized centres in order to determine the level of cleavage and the deficient protein. This first step may be followed by genetic analysis. The severity of the disease is highly variable, ranging from localized forms with little effect on quality of life to rapidly lethal forms. In generalized severe forms, the extent and chronicity of lesions, as well as mucosal involvement, can lead to systemic complications: malnutrition, pain, joint contractures, chronic inflammation, amyloidosis, cutaneous squamous cell carcinoma. Some specific forms are associated with other cutaneous signs (nail involvement, alopecia, hyperpigmentation, palmoplantar keratoderma) or extracutaneous involvement (muscular dystrophy or pyloric atresia). No curative treatment of EB is available today. EB requires multidisciplinary medical care, nursing, psychological and social management. This is best provided by a specialized network, involving reference centres, centres of expertise and daily caregivers. The goal of treatment is the prevention and treatment of lesions with specific non-adherent dressings and the prevention, detection and treatment of complications. It is essential not to traumatize the skin (bandaging, friction, etc.). Protein, gene or cell replacement therapy, and allogeneic bone marrow, cord blood or pluripotent stem-cell transplantation are currently being assessed. The aim of these French recommendations (national diagnostic and treatment protocol [PNDS]) is to provide healthcare professionals with guidance on the course of EB and on optimal patient management.

RARE-60. ATYPICAL RHABDOID TERATOID TUMOR: A CASE IN PREGNANCY AND ANALYSIS OF ADULT CASES TO DATE

Atypical rhabdoid teratoid tumors (ATRT) classically develop in infancy and are rare in adults. We present the 48th case to date, the third such during pregnancy. The disease tends to follow a biphasic course i.e. if growth is not arrested following the first relapse/ progression, death is almost universal. While typically rapidly fatal, as in our case, long-term remission appears possible. Uni-variable Cox proportional-hazards models of adult cases showed significantly worse survival with: glial differentiation (HR 7.3, p<0.01), leptomeningeal dissemination (HR 4.3, p<0.01) - these were highly correlated (chi-squared <0.01) and pregnancy (HR 3.9, p=0.09). The finding that glial differentiation worsens outcomes is novel. Improved survival was seen with extent of resection (ordinal scale; p<0.01 for model) and use of craniospinal irradiation (CSI; HR 0.2, p=0.07). Systemic chemotherapy was of marginal significance (HR=0.5, p=0.13). Use of intrathecal chemotherapy was too rare to draw any conclusions. 22/46 cases originated in midline structures next to CSF, thus leading to a high rate of leptomeningeal dissemination. All 10 cases in the pituitary were in females. 3/6 cases in those aged >50 began in/beside the spinal cord. We hypothesise that the cicumventricular organs, particularly the pituitaty and pineal glands are the most common origin of these tumors. There appears to be a pool of cells dividing in the above organs, rapidly in infancy and slowly throughout much of adulthood. Review of immunohistochemistry shows ectodermal elements, with epidermal-to-mesnchymal transition; thus ATRT may be a misnomer. Loss of INI1 is neither necessary not sufficient to account for ATRT. We suggest that the development of ATRT requires an epigenetic change. Treatment options in adults differ from infants in that CSI is a viable adjunct to chemotherapy. Myelotoxicity is a concern with multimodality treatment. We suggest that facilities for peripheral blood stem-cell transplant be available.

Безрецидивная выживаемость больных множе- ственной миеломой после аутотрансплантации периферических стволовых кроветворных клеток в зависимости от содержания CD45+CD19+ В-клеток в продукте афереза

Безрецидивная выживаемость больных множе- ственной миеломой после аутотрансплантации периферических стволовых кроветворных клеток в зависимости от содержания CD45+CD19+ В-клеток в продукте афереза

Comparative Outcomes after Haploidentical or Unrelated Donor Bone Marrow or Blood Stem Cell Transplantation in Adult Patients with Hematological Malignancies

Most patients eligible for allogeneic hematopoietic stem cell transplantation will require identification of an alternate (unrelated or mismatched related) donor. We explored the transplantation outcomes for a sequential series of 54 patients undergoing haploidentical donor transplantation (HAPLO) compared to those from a control group of patients receiving cells from matched or mismatched unrelated donors (URD) selected by diagnosis and stem cell source. Patients undergoing HAPLO transplantations received graft-versus-host disease (GVHD) prophylaxis with post-transplantation cyclophosphamide (Cy). Day 15 neutrophil recovery was lower after HAPLO than in URD recipients (43% versus 77%, P < .001), as was day 30 platelet recovery (67% versus 84%, P = .043). HAPLO patients receiving bone marrow achieved neutrophil engraftment at a median of 17 days and platelet engraftment at a median of 29 days, compared with 16 days and 24 days, respectively, for recipients of peripheral blood stem cells. The incidence of graft failure was similar for both HAPLO and URD recipients (P = .42). HAPLO recipients were more likely to reach donor CD3 chimerism >95% by day 28 after transplantation (88% versus 62%, P = .003). The cumulative incidence of grades II to IV acute GVHD (aGVHD) at 6 months after transplantation did not differ for these 2 groups (63% for HAPLO and 53% for URD recipients; P = .269), nor did the cumulative incidence of severe grade III/IV aGVHD (13% for HAPLO and 8% for URD recipients; P = .44). The cumulative incidence of moderate or severe chronic GVHD at 2 years did not differ, with probabilities of 24% for HAPLO and 18% for URD recipients (P = .43). The cumulative incidence of cytomegalovirus reactivation by day 100 after transplantation did not differ (45% for HAPLO and 46% for URD recipients; P = .96). The HAPLO recipients experienced a lower incidence of Epstein-Barr virus reactivation by day 100 (6% versus 32%, P < .001) but a higher incidence of Human Herpesvirus-6 reactivation (35% versus 10%, P = .001). Relapse risk, regimen-related mortality, progression-free survival, and overall survival probabilities did not differ between these 2 groups. These data support the use of HAPLO transplantation with post-transplantation Cy as an alternate transplantation technique for patients lacking HLA-matched sibling donors. Transplantation of peripheral blood stem cells does not appear to enhance the speed of neutrophil recovery. The different patterns of viral reactivation require additional studies to explain.

A multicenter clinical study to determine the feasible initial dose of lenalidomide for maintenance therapy in patients with multiple myeloma following autologous peripheral blood stem-cell transplantation.

Maintenance therapy with lenalidomide (LEN) for patients with multiple myeloma (MM) following autologous peripheral blood stem cell transplantation (auto-PBSCT) may be a promising option for preventing relapse or disease progression. However, the recommended dose of LEN has yet to be firmly established. We herein report the results of a multicenter clinical study for determining the feasible initial dose (FID) of LEN. In this trial, a total of 11 patients who achieved a very good partial response or complete response following auto-PBSCT were enrolled from five transplant centers in Japan. Three dose levels of LEN (level 0, 5 mg; level 1, 10 mg; and level 2,:15 mg) were tested in this study. FID was defined as the maximum estimated dose at which 70% of the patients could receive maintenance therapy for 12 weeks without any serious adverse events or disease progression. Using a continual reassessment method, 6 patients were assigned to level 0 and the remaining 5 patients were assigned to level 1. All 6 patients (100%) at level 0, but only 2 patients (40%) at level 1, completed 12 weeks of administration with their assigned dose of LEN. The results of our study demonstrated that, although 5 mg of LEN was acceptable in terms of safety, 7.5 mg of LEN may also be an acceptable FID.

The Effects of Oral Cryotherapy on Chemotherapy-Induced Oral Mucositis in Patients Undergoing Autologous Transplantation of Blood Stem Cells: A Clinical Trial.

BackgroundOral mucositis is one of the irritating side effects of chemotherapy in patients undergoing bone marrow transplantation. However, up until now, the common methods of oral mucositis therapy have failed to show significant effects.ObjectivesThe aim of this study was to investigate the effects of local cryotherapy on the intensity of chemotherapy-induced oral mucositis in autologous bone marrow transplantation patients.Patients and MethodsIn this single, blinded, randomized clinical trial, 29 patients undergoing stem cell transplantation in Iran were selected by convenience sampling, and randomly allocated to control (n = 13) and intervention groups (n = 16). In the intervention group, cryotherapy was applied, while the control group received a normal saline mouthwash. The severity of the mucositis and neutrophil rate were investigated in five periods, based on the world health organization (WHO) scales. The data were analyzed using descriptive statistics, the Mann-Whitney test, repeated measures analysis of variance (ANOVA), and linear regression.ResultsIn both groups, the mucositis reached its peak intensity on the 7th day, and the least intensity was obtained on the 21st day. The neutrophil rate reached the minimum value on the 7th day, then increased up to the 21st day. The two groups showed no significant differences between the mucositis severity on the 14th and 21st days (P = 0.164), while the severity of the mucositis in the cryotherapy group was significantly less than that in the saline mouthwash group (1.81 < 2.54 and 0.13 < 0.92, respectively) on the 7th and 14th days (P < 0.05). There was no significant difference in the neutrophil rate between the groups.ConclusionsThe results showed that cryotherapy is more effective than the saline mouthwash in reducing the severity of mucositis. This method is recommended for the prevention of mucositis in bone marrow transplantation.

Outpatient Haploidentical Peripheral Blood Stem-Cell Transplantation with Post-Transplant Cyclophosphamide in Children and Adolescents

Patients with high-risk hematological malignancies have a poor prognosis without a hematopoietic stem cell transplant. An HLA- haploidentical donor is available in 95% of the cases, and post-transplant cyclophosphamide permits the use of T-cell replete grafts in settings were ex-vivo manipulation is not available. The experience with HLA-haploidentical HSCT with PBSC and post-tranplant Cy in the pediatric and adolescent population is limited; we report the following experience.We retrospectively collected data on 25 patients (0 to 21 years old) with hematological malignancies, who underwent ambulatory haploidentical HSCT with post-transplant Cy from November 2011 to November 2014. The different conditioning regimens are described in Table 1. All patients received high-dose Cy(50mg/kg) on days +3 and +4. Cyclosporine A (CYA; 6mg/kg/d per os) and mycophenolate mofetil (MMF; 15mg/kg two times daily per os) were started on day +5. MMF was discontinued on day +35 and tapering of cyclosporin started day +90 in the absence of GVHD. All patients received anti-microbial prophylaxis for bacteria, fungal, herpes infection and Pneumocystis jiroveci according to institutional practices. First chimerism was performed at day +30, and second chimerism at day +100. Primary graft failure was defined when neutrophil counts did not exceed 0.5 x 109/L by day +30. Acute and chronic GVHD were graded according to NIH criteria.Patient, donor and stem-cell harvest characteristics are described in Table 1. All patients had high risk hematological malignancies. There were 5 patients who underwent their first transplant on 1st CR, 4 with ALL with high risk cytogenetics and 1 with AML. All other patients were defined as high risk because they were refractory/relapsed.Twenty-three patients (92%) had neutrophil engraftment after a median 17 (7-24) days. Platelet engraftment was observed in 20 (80%) patients after a median of 14.5 (11-23) days, 3 (12%) patients did not have platelet counts below 20,000/mcL. One patient was catalogued as a primary failure for not achieving neutrophil and platelet engraftment by day +30. One patient died before engraftment at day +10 of septic shock. Four patients (16%) died before day +30. The only patient that did not have a complete chimerism, had a diagnosis of AML and 30% of donor cells by day +30, by day +45 relapse of disease was documented.After a median follow-up of 157 days, 13 patients (52%) remain alive, with an estimated 1-year OS of 52% (95%CI: 30.4 - 65.6%).Nine patients (36%) died of complications (mainly infectious) not related to relapse at a median time of 66 days (10-579 days) from stem cell infusion. Nine patients (36%) relapsed in a median time of 105 days (45-288 days); three of those patients died at days +150, +113 and + 370 from transplant. Estimated 1 year event-free survival is 40.2% (95%CI: 41.3 - 75.8%) (Figures 1 and 2). Patients transplanted on 1st CR had a median follow-up of 664 days with an OS and EFS of 80% (4 patients), which was statistically different from the rest of the population (p=0.03) (Figure 3).Among those who engrafted (n=21), 9 cases (42.9%) had grade 2-4 acute GVHD and 4 cases (19%) of grade 3-4 acute GVHD. Three patients (14.3%) developed chronic GVHD, two had mild skin or liver cGVHD. One patient had severe (NIH stage 3) skin cGVHD, she was alive and with a grade 2 cGVHD until last follow up at day +893.Outpatient procedure, HLA-haploidentical HSCT including PBSC as a stem cell source, and post-transplant T-cell in vivo depletion using high-dose cyclophosphamide is feasible in children and adolescents, with acceptable rates of response and GVHD.Table 1Patient, donor and harvest characteristicsVariableN=25Age, median(range in years)10 (1-21)Gender, n(%) Male Female17 (68%) 8 (32%)Diagnosis, n(%) ALL-B ALL-T AML CML16 (64%) 2 (8%) 5 (20%) 2 (8%)Time from diagnosis to transplant (months)17.2 (1.9-153.5)Conditioning regimen, n(%) Cy 1500mg/m2 + Flu 75mg/m2 + Bu 9.6mg/kg (IV) Cy 1050mg/m2 + Flu 75mg/m2 + Bu 12 mg/kg (oral) Cy/VP-16/RT Cy/Flu/Mel16 (64%) 6 (24%) 2 (8%) 1 (4%)Donor, n(%) Mother Father Sister20 (80%) 3 (12%) 2 (8%)Donor age, median(range in years)38 (17-49)Infused CD34+ x 106/kg, median(range)11 (3.2-20) [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Saving lives with stem cell transplants

Blood stem cell transplants can be life-saving for some patients, but the chances of finding a matching donor are small unless a large number of potential donors are evaluated. Many nations maintain large registries of potential donors who have offered to donate stem cells if they are the best available match for a patient needing a transplant. An alternative source of stem cells, umbilical cord blood, is stored in banks. Everyone faces a small probability of needing a transplant which will increase their likelihood of survival. The registries and cord blood banks are thus an interesting example of a pure public good with widely dispersed benefits. This paper explores the gains in survival probability that arise from increased registry and bank sizes and uses value of statistical life methods to estimate benefits and compare them to costs. Our results suggest that for the United States and for the world as a whole, the sum of marginal benefits of an increase in either the adult registry or the cord blood bank exceeds marginal costs. However, marginal benefit-cost ratios for the adult registry are much greater than those for the cord blood banks, which suggests that to the extent that these two sources of life saving compete for public funds it may be preferable to prioritize expansion of the adult registry over cord blood banks.

Reproducibility and prognostic significance of morphologic dysplasia in de novo acute myeloid leukemia

The 2008 WHO classification of acute myeloid leukemia includes a category of acute myeloid leukemia with myelodysplasia-related changes; however, the significance of multilineage dysplasia alone is controversial and its reproducibility has not been evaluated in acute myeloid leukemia. We performed an in-depth analysis of morphologic dysplasia in 159 de novo acute myeloid leukemia cases lacking myelodysplasia-related cytogenetic abnormalities. Using the 2008 WHO criteria, there were 89 acute myeloid leukemia—not otherwise specified (56%) and 43 acute myeloid leukemia with myelodysplasia-related changes (27%), while 27 cases were ambiguous as to myelodysplasia-related changes status due to limited maturing cells (acute myeloid leukemia—not evaluable, 17%). On multivariable analysis, neither acute myeloid leukemia with myelodysplasia-related changes nor acute myeloid leukemia—not evaluable showed significantly different event-free survival compared with acute myeloid leukemia—not otherwise specified in the 137 patients treated with induction chemotherapy. When individual dysplastic features were analyzed, only micromegakaryocytes and hypogranulated myeloid cells emerged as factors significantly associated with shorter event-free survival in a multivariable analysis that included the other significant covariates of age, white blood count, platelet count, abnormal karyotype and stem-cell transplantation. Our findings indicate that the current 2008 WHO definition of multilineage dysplasia in acute myeloid leukemia in its current form is not optimal, and that the use of a more restricted definition of morphologic dysplasia results in more relevant risk stratification that is independent of other conventional prognostic factors.

HLA Typing for the Next Generation.

Allele-level resolution data at primary HLA typing is the ideal for most histocompatibility testing laboratories. Many high-throughput molecular HLA typing approaches are unable to determine the phase of observed DNA sequence polymorphisms, leading to ambiguous results. The use of higher resolution methods is often restricted due to cost and time limitations. Here we report on the feasibility of using Pacific Biosciences’ Single Molecule Real-Time (SMRT) DNA sequencing technology for high-resolution and high-throughput HLA typing. Seven DNA samples were typed for HLA-A, -B and -C. The results showed that SMRT DNA sequencing technology was able to generate sequences that spanned entire HLA Class I genes that allowed for accurate allele calling. Eight novel genomic HLA class I sequences were identified, four were novel alleles, three were confirmed as genomic sequence extensions and one corrected an existing genomic reference sequence. This method has the potential to revolutionize the field of HLA typing. The clinical impact of achieving this level of resolution HLA typing data is likely to considerable, particularly in applications such as organ and blood stem cell transplantation where matching donors and recipients for their HLA is of utmost importance.

Chemokine and lymph node homing receptor expression on pDC vary by graft source

A randomized clinical trial of BM vs. blood stem cell transplants from unrelated donors showed that more plasmacytoid dendritic cells (pDCs) in BM grafts was associated with better post-transplant survival. Here, we describe differences in homing-receptor expression on pDC to explain observed differences following BM vs. blood stem cell transplantation.

High-dose chemotherapy and autologous peripheral blood stem cell (PBSC) transplantation with non-cryopreserved PBSCs in multiple myeloma.

e19577 Background: Peripheral blood stem cells (PBSCs) are commonly used as the graft source during hematopoietic cell transplantation(HCT). The aim of this retrospective evaluation was to compare ...

Treatment of Fanconi Anemia with Transplantation of Umbilical Cord Blood stem Cells: One Case Report and Literature Review

Objective To study the curative effect of transplantation of umbilical cord blood stem cells on Fanconi anemia (FA).Methods One patient with FA aged 15 was enrolled in this study in our center on May 10th 2012.The FA patient was transplanted with umbilical cord blood stem cells.Conditioning procedure included fludarabine (Flu) +-cyclophosphamide (CTX) +-rabbit anti-human T-lymphocyte immunoglobulin (ATG).Therapeutic effect of transplantation was reported with its relevant literature reviewed.Results The times to neutrophil ＞0.50 × 109/L and platelet ＞ 20 × 109/L engraftment were 16 d and 21 d,respectively.At the same,the patient achieved full donor chimerism (FDC).No severe infection and other complications occurred.Conclusions Transplantation of umbilical cord blood stem cells is a safe and effective treatment modality for this FA patient. Key words: Fanconi anemia; Umbilical cord blood; Hematopoietic stem cell transplantation

High CD8 Cell Doses Correlate with Reduced Relapse Risk and Improved Survival after Allogeneic Peripheral Blood Stem-Cell Transplantation with Reduced-Intensity Conditioning

High CD8 Cell Doses Correlate with Reduced Relapse Risk and Improved Survival after Allogeneic Peripheral Blood Stem-Cell Transplantation with Reduced-Intensity Conditioning

下顎骨に転移が認められた網膜芽細胞腫の1例

Retinoblastoma is a malignant tumor originally derived from the immature retina in infancy and childhood. It usually occurs in patients younger than 2 years. Although the prognosis after treatment is relatively good, the prognosis becomes poor if extraocular extension, distant metastases, or both occur. A 1 and a half-year-old male had been given a diagnosis of a retinoblastoma of the left eye and received conservative treatment. A recurrent tumor was later found, and metastatic tumors were detected in the bone marrow, femur, and mandible 6 months later. Chemotherapy was performed at that time. Thereafter, enucleation of the left eye and peripheral blood stem-cell transplantation with ultra-high-dose chemotherapy were performed. Consequently, cerebrospinal irradiation was also performed. The patient has been in remission for 6 years. The mandible has no findings of recurrence and no dysgenesis. The permanent teeth have nearly all erupted with short roots and provide good occlusion.

Amplification of functional myeloid-derived suppressor cells during stem cell mobilization induced by granulocyte colony-stimulation-factor

The effects of granulocyte colony-stimulation-factor (G-CSF) on stem cell mobilization and its impact on the amplification of myeloid-derived suppressor cells (MDSCs) of donor mice were examined. A mouse model of stem cell mobilization was established by consecutive subcutaneous injection of 100 μg/kg G-CSF for 5 days. The blood from the donor mice was routinely examined during mobilization. Stem cells and MDSCs were analyzed by flow cytometry. The immunosuppressive molecules derived from MDSCs in serum and spleen, including hydrogen dioxide (H2O2) and nitric oxide (NO), and the activity of nitric oxide synthase (NOS) were determined during the mobilization. Apoptosis of T lymphocytes was assessed by using Annexin-V/PI. During stem cell mobilization, the number of lymphocytes and white blood cells in the peripheral blood was increased, and peaked on the 4th day. The number of stem cells in G-CSF-treated mice was significantly greater than that in controls (P<0.01). The expansions of MSDCs were also observed after G-CSF mobilization, with a more notable rate of growth in the peripheral blood than in the spleen. The activity of NOS and the production of NO were increased in the donor mice, and the serum H2O2 levels were approximately 4-fold greater than the controls. Consequently, apoptosis of T lymphocytes was increased and showed a positive correlation with the elevated percentage of MDSCs. It was concluded that G-CSF could provide sufficient peripheral blood stem cells for transplantation. Exogenous administration of G-CSF caused the accumulation of MDSCs in the peripheral blood and the spleen, which could lead to apoptosis of T lymphocytes and may offer a new strategy for the prevention and treatment of graft versus host disease.