Mohamed Ramadan El-Shanshory

Expression of lung resistance protein and multidrug resistance-related protein (MRP1) in pediatric acute lymphoblastic leukemia

Multidrug resistance (MDR) is a phenomenon by which cells become resistant to unrelated chemotherapeutic agents. The prognostic value that lung resistance protein (LRP) and multidrug resistance-related protein 1 (MRP1) have in the setting of pediatric acute lymphoblastic leukemia (ALL) is controversial. The aim of this study was to investigate the expression of LRP and MRP1 and effect on clinical outcome and prognosis. The mRNA expression of LRP and MRP1 were analyzed in leukemic blasts of 34 pediatric ALL patients. LRP and MRP1 mRNA expression were detected in 41.2% and 35.3%, respectively. Eleven (91.7%) of 12 patients without LRP achieved CR compared with 9 (50.0%) of 18 with LRP expression. Similarly, 11 (100%) of 11 patients without MRP1 expression achieved CR compared with 9 (47.4%) of 19 with MRP1 expression and higher LRP expression rate or MRP1 expression rate was present in patients with relapse than MDR genes negative patients. The expression of either of two genes was associated with poorer 2-year survival. Also, patients expressing both genes had poorer outcomes and had worse 2-year survival. We suggest that MDR expression affects complete remission and survival rates in ALL patients. Thus, diagnosis appears to provide prognostic information for pediatric ALL.

Prevalence of hepatitis C infection among children with β-thalassaemia major in Mid Delta, Egypt: a single centre study

BACKGROUND Transfusion dependant patients are at a higher risk of acquiring bloodborne infections even under conditions of safe transfusion. This study was designed to determine sero-prevalence of hepatitis C infection and possible associated risk factors in thalassaemic children. METHODS One hundred and twenty five children with β thalassaemia major (β-TM) were recruited from the Haematology/Oncology Unit, Paediatric Department, Tanta University Hospital, Egypt, between April 2010 and October 2011. Patients underwent history taking, full clinical examination, routine investigations and venous blood sampling. Serum was stored at -20°C till tested for hepatitis C (HCV Ab) and B (HBsAg) by ELISA. HCV Ab positive cases were confirmed by PCR. RESULTS All patients were HBsAg negative. HCV Ab ELISA was positive in 76%, negative in 20% and equivocal in 4%. Fifty patients (40%) had positive PCR for HCV. PCR showed low viraemia in 78%, moderate viraemia in 20% and high viraemia in 2%. A positive family history of HCV, history of minor operative intervention and/or dental procedures were significantly associated with higher frequency of HCV infection in thalassaemic children, while amount and frequency of transfused blood, age at transfusion and chelation state were not. CONCLUSION HCV infection is highly prevalent in children with β-TM in Egypt despite strict pre-transfusion blood testing. This should arouse the attention for environmental and community acquired factors. Quality management to insure infection control in minor operative procedures and adding more sensitive tests for blood screening are recommended.

Evaluation of immune status against hepatitis B in children with thalassemia major in Egypt: A single center study

Objectives: Thalassemic children with repeated blood transfusion are at higher risk of suffering transfusion related infections including hepatitis B virus (HBV). HBV vaccine immunogenicity in several studies showed variable response rates. The aim of this study is to evaluate the immunogenic effect of hepatitis B vaccine in thalassemic children at different age groups. Materials and methods: After ethical approval and informed parent consent, 125 diagnosed thalassemic patients were recruited from the Hematology/Oncology Unit, Pediatric Department, Tanta University Hospital. Patient’s transfusion, and vaccination history, clinical data, and blood samples were obtained. Patient’s sera were stored at -20°C till tested for Anti-hepatitis B surface (anti-HBs) by ELISA. Patients with titers <10 IU were tested for HBs-Ag. Results: Although none of our cases had hepatitis B virus infection, only 20.8% had a protective anti-HBs titer (>10 IU/L). Significantly higher percentage of protected patients (40.1%) were younger than 3 years of age, while age groups above 3years showed a significant trend towards having non protective titers (p=0.003). Anti-HBs titers weren’t correlated to age, ferritin, liver enzymes, and duration of transfusion or number of transfused packs. Conclusion: Protective Anti-HBs titer was reduced after age of 3 years in our patients. So, we recommend screening of thalassemic patients at age of 3 years to evaluate the need of a booster dose. J Microbiol Infect Dis 2012; 2(2): 44-49

Chemotherapy alters the increased numbers of myeloid-derived suppressor and regulatory T cells in children with acute lymphoblastic leukemia

Abstract Introduction: Acute lymphoblastic leukemia (ALL) is the most common cancer diagnosed in children. The precise mechanism behind the relapse in this disease is not clearly known. One possible mechanism could be the accumulation of immunosuppressive cells, including myeloid-derived suppressor cells (MDSCs) and T regulatory cells (Tregs) which we and others have reported to mediate suppression of anti-tumor immune responses. Aim: In this study, we aimed to analyze the numbers of these cells in a population of B-ALL pediatric patients. Methods: Peripheral blood samples withdrawn from B-ALL pediatric patients (n = 45 before, during and after the induction phase of chemotherapy. Using multi parametric flow cytometric analysis. MDSCs were identified as Lin–HLA-DR–CD33+CD11b+; and Treg cells were defined as CD4+CD25+CD127–/low. Results: Early diagnosed B-ALL patients showed significant increases in the numbers of MDSCs and Tregs as compared to healthy volunteers. During induction of chemotherapy, however, the patients showed higher and lower numbers of MDSCs and Treg cells, respectively as compared to early diagnosed patients (i.e., before chemotherapy). After induction of chemotherapy, the numbers of MDSCs and Treg cells showed higher increases and decreases, respectively as compared to the numbers in patients during chemotherapy. Conclusion: Our results indicate that B-ALL patients harbor high numbers of both MDSCs and Tregs cells. This pilot study opens a new avenue to investigate the mechanism mediating the emergence of these cells on larger number of B-ALL patients at different treatment stages.

Increases in the numbers of cells with the phenotype of myeloid-derived suppressor and regulatory T cells in children with acute lymphoblastic leukemia

Background Acute lymphoblastic leukemia (ALL) is the most common cancer diagnosed in children. The precise mechanisms behind the relapse in this disease are not clearly known. One possible mechanism could be the accumulation of regulatory cells including myeloid-derived suppressor cells (MDSCs) and T regulatory cells (T regs ) which we and others have reported to mediate suppression of anti-tumor immune responses. Few previous studies investigated the roles of T reg cells in ALL, while no studies reported the emergence of MDSCs in ALL. Aim Therefore, we aimed to analyze the frequencies and phenotype of these cells in a group of Egyptian B-ALL pediatric patients (n=45). Materials and methods MDSCs were identified as Lin − HLA-DR − CD33 + CD11b + ; and T reg cells as CD4 + CD25 + CD127 −/low using multiparametric flow cytometer. Results We found significant increases in the numbers of MDSCs and T reg cells in B-ALL patients as compared to healthy control volunteers. B-ALL patients showed significant increased numbers of MDSCs and T regs before chemotherapy when compared to healthy volunteers. The numbers of MDSCs were more increased while the numbers of T reg cells were more decreased in patients during induction of chemotherapy. The highest increase in the numbers of MDSCs was observed in patients after induction of chemotherapy, while T reg cells showed the most significant decreased numbers after induction of chemotherapy. Conclusion Our results indicate that B-ALL patients harbor both MDSCs and T reg cells, opening a new avenue to investigate the mechanism mediating the emergence of these cells in larger numbers of patients at different treatment stages.

Study of peripheral stem cells mobilization as a treatment line of pediatric dilated cardiomyopathy

BACKGROUND Mobilizing hematopoietic stem cells may be a promising intervention for the treatment of idiopathic dilated cardiomyopathy (IDCM) in infant and children. So the aim of the work is to evaluate the efficacy of granulocyte-colony stimulating factor (G-CSF) as a therapeutic modality in pediatric IDCM. METHODS A randomized clinical trial was conducted on 40 pediatric patients with IDCM. They were subjected to history taking, clinical examination, serum lactate dehydrogenase (LDH), total creatinine phosphokinase (CPK), creatinine phosphokinase isoenzyme B (CK-MB) isoenzyme, and peripheral blood CD34(+) cell assessment before and at day 7 after subcutaneous G-CSF injection for 5 consecutive days. Echocardiography was done before and 1, 3 and 6 months after therapy. RESULTS Clinical improvement in the form of regression of patients Modified Ross heart failure (MRHC) classification classes. Increased percentage of CD34(+) mobilized cells from the bone marrow, and significant increase in blood counts especially white blood cells 7 days after G-CSF injection. Significant improvement was found in echocardiographic data evaluating systolic function of the heart [Ejection fraction, Fractional shortening and systolic velocity at mitral annulus (Sm)]. CONCLUSIONS Administration of G-CSF may be beneficial in improving systolic functions of the heart in pediatric IDCM and more studies with a large number of patients are needed.

Children with acute lymphoblastic leukemia show high numbers of CD4+ and CD8+ T-cells which are reduced by conventional chemotherapy

Background: Acute lymphoblastic leukemia (ALL) is considered as one of the most common cancer in pediatric malignancies. Among ALL, B-cell Acute Lymphoblastic Leukemia (B-ALL) represents 80% to 85% of the childhood ALL. Problem: Although anti B-ALL chemotherapy kill B-ALL, it associates with alteration in the numbers of CD4+ and CD8+ T-cells, and thus impacts the overall immunity. Aim: To evaluate the impact of anti B-ALL on the numbers of CD4+ and CD8+ T-cells in correlation to the numbers of CD10+ B cells in B-ALL pediatric patients. Materials and Methods: Peripheral blood samples were drawn from previously diagnosed B-ALL before (n = 10 cases) and after (n = 10 cases) chemotherapy as well as from healthy controls (n = 10 cases). The numbers of CD4+, CD8+ T-cells and CD10+ B cells were measured in these samples by flow cytometry. Results: As expected, the numbers of CD10+ B-cells were increased in B-ALL patients before chemotherapy which were associated with increases in the numbers of CD4+ and CD8+ T-cells. Chemotherapy of B-ALL patients, during the induction phase, induced dramatic decreases in the numbers of CD10+ B cells, which were associated with decreases in the numbers of CD4+ and CD8+ T-cells. Tin spite of this alteration, the ratio of CD4/CD8 in B-ALL patients were remained similar before and after chemotherapy as compared to those in healthy controls. Conclusion: Anti B-ALL chemotherapy induces alterations in the frequencies of T-cell subsets. Given the importance of these cells in anti-tumor immunity, our data may lead to further studies to investigate the different subsets of these cells, in particular regulatory T-cells.

Reduction in the numbers of CD33+ myeloid population in Egyptian children with B-linage acute lymphoblastic leukemia and its recovery after induction of chemotherapy

Background: Acute lymphoblastic leukemia (ALL) is biologically and clinically considered as a heterogeneous neoplasm of lymphoid progenitor cells. About 85% of children with ALL are diagnosed as B-ALL, expressing CD19; the typical marker of normal B cells. Problem: Given that the chemotherapy associated with leucopenia, in particular myeloid cells (CD33+ cells), Aim: the main aim of this study was to analyze the numbers of these cells in children with B-ALL before and after induction of chemotherapy. Materials and Methods: The frequencies of CD33+ myeloid cells and CD19+ B-cells were analyzed in the peripheral blood patients before (n = 10) and after (n = 10) induction of chemotherapy as well as in healthy volunteers (n = 10) using multiparametric flow cytometry. Results: As expected, B-ALL patients showed high numbers of CD19+ cells before induction of chemotherapy; where the numbers of these cells were reduced upon the induction of chemotherapy. CD33+ myeloid cells showed decrease in numbers in B-ALL patients before chemotherapy as compared to healthy control volunteers. Interestingly, treatment of B-ALL patients with chemotherapy-induced almost recovery of the numbers of these cells. Conclusion: CD33+ myeloid cells are increased in numbers after induction of chemotherapy, indicating to a dynamic mobilization or differentiation of their precursors into circulation. This study opens a new avenue to characterize the phenotype and function of these cells in different hematological malignancies; in particular, they may harbor regulatory cells.

Immunostimulatory Effects of Triggering TLR3 Signaling Pathway — Implication for Cancer Immunotherapy

Immunostimulation based therapies hold promise of disease-specific interventions without the toxicity and other side effects, which are associated with traditional therapeutic modalities. Unfortunately, the exact manifestation of their therapeutic benefits and the mechanisms of their action are still pending for most immunotherapeutic strategies. Virtually, such kinds of treatments are ideal to establish standards of care and secure, as well as improve therapeutics outcomes. A growing interest for studying and understanding immunostimulation based therapeutics’ strategies has increased since, it could stimulate different components of innate immunity and consequently stimulation of adaptive immunity [1-3].