Impact of hydroxyurea on lymphocyte subsets in children with sickle cell anemia.

BACKGROUND: Hydroxyurea (HU) has beneficial effects in the management of sickle cell anemia (SCA), but there is a paucity of data on the effect of HU on immune cells in SCA. Herein we aimed to evaluate the effect of HU on immune profiles of Egyptian children with SCA. METHODS: This was a controlled prospective cohort study conducted in 30 children with SCA and 30 healthy age-matched controls. Flow cytometry was used to evaluate lymphocyte profiles, including CD8+ T, CD19+ B, CD3+, CD4+, natural killer (NK), NK T, T helper 1 (Th1), Th2, T cytotoxic (Tc1), and Tc2 cells, prior to and after 1 year of treatment with HU. RESULTS: HU treatment led to significant increases in hemoglobin (Hb), red blood cell, and hematocrit counts and a significant decrease in the percentage of sickle Hb, with subsequent improvement in SCA complications. Compared with baseline values, CD3+, CD4+, Th1, and CD8+ T cells were significantly increased, while NK, Th2, and Tc2 cells were significantly decreased, with a resulting increase in the Th1/Th2 and Tc1/Tc2 ratios. CONCLUSIONS: HU has the beneficial effect of restoring the abnormally elevated immune parameters in children with SCA. IMPACT: Hydroxyurea treatment restores the abnormal immune parameters in children with sickle cell anemia. HU treatment led to significantly increased CD3+, CD4+, Th1, and CD8+ T cells, while NK, Th2, and Tc2 cells were significantly decreased, with a resulting increase in the Th1/Th2 and Tc1/Tc2 ratios. Our study showed the impact of HU therapy on immune parameters in children with SCA.

Regulatory T-cell phenotypes in children with sickle cell disease.

BACKGROUND: Regulatory T cells (Tregs) are linked to a reduction in alloreactive immune responses, but few studies have investigated the impact of hydroxyurea (HU) therapy on Tregs in sickle cell disease (SCD). METHODS: Our case-controlled study presented here included two groups, the first comprising 60 pediatric SCD patients, 30 of whom did not receive any treatment and 30 who received HU, and the second group consisting of 30 healthy controls. Flow cytometry was used to evaluate the percentage of CD4+CD25+highFoxp3+ Tregs present and their phenotypes. RESULTS: The percentage of CD4+CD25+high Tregs was significantly increased in untreated SCD patients in comparison to treated SCD patients and controls. Conversely, treated SCD children had a lower percentage of CD4+CD25+high Tregs than controls. In addition, a significant increase in the percentage of CD4+CD25+highFoxp3+ Tregs was found in untreated SCD patients, compared to in HU-treated patients and controls. The percentage of naive CD45RA+ Tregs was significantly decreased in untreated SCD patients when compared to other groups. CONCLUSIONS: Among children with SCD, HU treatment exhibited significant qualitative and quantitative effects on Tregs by decreasing their frequency, and increasing the proportion of naive CD45RA+ Tregs and reducing levels of the most suppressive Tregs: HLA-DR+, CD39+, and CD69+. IMPACT: Among children with, SCD, HU treatment exhibited significant qualitative and quantitative effects on Tregs. HU treatment in SCD decreases the frequency of Tregs, as well as the levels of the most suppressive Tregs: HLA-DR+, CD39+, and CD69+. At the same time, HU increases the proportion of naive CD45RA+ Tregs. Our study showed the impact of HU therapy on Tregs in children with SCD.

Regulatory T-lymphocyte subsets in children with chronic immune thrombocytopenia after high-dose of dexamethasone.

BACKGROUND: Immune thrombocytopenia (ITP) is an acquired autoimmune disease. This study's objective was to estimate the variations in the population of CD4+CD25+High FoxP3+ cells (CD4+ regulatory T-lymphocytes; Tregs) in previously untreated children with chronic ITP managed in Assiut University Hospitals, as well as to evaluate the efficacy of high-dose dexamethasone (HD-DXM) in these patients. METHODS: In this study, we investigated the frequencies of T-lymphocyte subsets in 27 untreated children with chronic ITP. RESULTS: Prior to treatment, the percentages of CD4+CD25High cells and Tregs were significantly lower in the chronic ITP group compared to the control group (p = 0.018 and p < 0.0001, respectively). After treatment with HD-DXM, Tregs and platelets were significantly increased in these patients (p < 0.0001 for both). CONCLUSIONS: Our results suggest that Tregs are deficient in children with chronic ITP and that HD-DXM immunosuppressive therapy can restore the levels of these cells. IMPACT: CD4+CD25High cells and Tregs were significantly lower in children chronic ITP compared to healthy control. HD-DXM treatment led to significantly increased Tregs and platelets in these patients. Our results suggest that Tregs are deficient in children with chronic ITP and that HD-DXM immunosuppressive therapy can restore the levels of these cells.

Dendritic cells and monocyte subsets in children with Gaucher disease.

BACKGROUND: There are minimal data on the frequencies of monocyte subsets and dendritic cells (DCs) in children with Gaucher disease (GD), as nearly all previous studies have involved adult patients. Consequently, we aimed to describe the changes in these cell subpopulations in children with GD type 1 who were on regular enzyme replacement therapy (ERT). METHODS: This case-control study included 25 children with GD1 and 20 healthy controls. All participants underwent investigations such as complete blood count and flow cytometric assessment of DC and monocyte frequencies and phenotype. RESULTS: We found that GD1 children had significantly reduced percentages of both types of DCs, i.e., plasmacytoid DCs and myeloid DCs, compared to the control group. There was also a significant reduction in absolute monocyte numbers and percentage of classical monocyte. Moreover, the GD1 children had higher frequencies of non-classical and intermediate monocytes than the control group. CONCLUSIONS: Our results so far indicate that, when compared to the control group, the GD1 children had significantly reduced total and classical monocyte, with significantly decreased frequencies for both types of DCs. These changes can contribute to immunological abnormalities in pediatric patients with GD1. IMPACT: Children with Gaucher disease type 1 (GD1) have significantly reduced total and classical monocyte frequencies, with decreasing percentages for both types of dendritic cells. GD1 children had significantly reduced frequencies of myeloid and plasmacytoid dendritic cells as compared to the controls. The GD1 children also had significant changes in monocyte subsets when compared to the controls. Our results show that monocytes and dendritic cells' significant changes could contribute to immunological abnormalities in pediatric patients with GD1.

Analysis of Toll-Like Receptor-2 and 4 Expressions in Peripheral Monocyte Subsets in Patients with Type 1 Diabetes Mellitus.

Background: Dysfunction of the peripheral blood monocytes in the form of changes in their proportion, cytokines or pattern-recognition receptors (PRR) expressions may be involved in the pathogenesis of type 1 diabetes mellitus (T1DM). Our aim is to analyze the three monocyte subsets; classical, non-classical and intermediate monocytes and their expression of Toll-like receptors 2 (TLR-2) and 4 (TLR-4) in T1DM patients. Methods: The peripheral blood monocytes of 20 T1DM patients were analyzed by Flow cytometry to measure their count and TLR-2 and TLR-4 expression. Results: T1DM patients had more non-classical and intermediate monocytes, whereas classical monocytes were comparable between patients and control (20 healthy volunteers). Classical, non-classical and intermediate monocytes had no significant correlations with hemoglobin (Hb) A1C in controls, while all subsets showed positive correlations with HbA1C in T1DM. TLR-2 and TLR-4 expression were significantly increased in classical monocytes in patients, especially those with diabetic ketoacidosis (DKA), and both of them showed positive correlations with the duration of T1DM. The expression of TLR-2 inside non-classical monocytes showed a negative correlation with LDL cholesterol and TLR-4/TLR-2 ratio showed positive correlations with the duration of T1DM and negative correlations with total cholesterol. The expression of TLR-2 inside intermediate monocytes showed positive correlations with the duration of T1DM and TLR-4/TLR-2 ratio showed negative correlations with the duration of T1DM Conclusions: The observed changes in both proportions and TLR-2 and TLR-4 expression of monocyte subsets can raise the possible role in the pathogenesis of early stages of T1DM and DKA. Abbreviations APC: allophycocyanin; CBC: complete blood picture; DKA: diabetic acidosis; DM: diabetes mellitus; FITC: fluorescein isothiocyanate; FSC: forward scatter; Hb: haemoglobin; MFI: mean channel fluorescence intensity; PE: phycoerythrin; PRR: pattern-recognition receptors; SPSS: statistical package for the social sciences; SSC: side scatter; T1DM: Type1DM; TLRs: toll-like receptors.

Intracranial hemorrhage in primary immune thrombocytopenia (ITP): 20 years' experience in pediatrics.

Incidence of intracranial hemorrhage (ICH) among children with primary immune thrombocytopenia (ITP) varies among different studies. We published data during the period of 1997-2007 of ICH in children with primary ITP, addressing risk factors and outcome. The aim of this study is to assess changes in incidence, risk factors, and outcome of ICH in children with ITP from last decade and to report the overall 20 years' experience. We compared 2008-2018 with the decade before it. Data of children with ITP and ICH during study period and ITP control cases were analyzed. Neurosurgical intervention and outcome were also reported. A total of 4340 children with primary ITP were evaluated. Twenty-five (0.63%) ICH events were reported over 2 decades. Head trauma, hematuria, and platelet counts < 10 × 109/L were the risk factors mostly associated with ICH. Overall mortality was 24%, and a further 28% had neurologic sequelae. Neurosurgical intervention was done in 12% of cases with good outcome.Conclusion: Persistent platelet counts < 10 × 109/L were a significant risk factor for ICH in both time periods, while head trauma and hematuria were more reported in the period of 2008-2018 as significant risk factors for ICH. Outcome was comparable in both periods. What is Known: • ICH is a rare complication of ITP; however, early recognition of risk factors and aggressive treatment might lead to complete recovery without sequalae. Platelet counts less than < 10 × 109/L are the main risk factor for ICH. Few studies reported other significant risk factors. What is New: • Hematuria and head trauma are significant risk factors for ICH in ITP, in addition to having a persistently low platelet count < 10 × 109/L. (more than 90 days in chronic ITP, 45 days in persistent and 21 days in acute ITP) • Combined treatment with IVIG and HDMP followed by platelet transfusion was associated with complete recovery without sequelae in almost 50% of patients.

High dose dexamethasone as an alternative rescue therapy for active bleeding in children with chronic ITP: clinical and immunological effects.

High-dose dexamethasone (HD-DXM) is debated as a second-line therapy for chronic Immune thrombocytopenia (ITP) in children. The aim of this study is to evaluate the efficacy and safety of HD-DXM as an emergency therapy in uncontrolled bleeding in children with chronic ITP and to assess its immunological effect on dendritic cells (DCs) percentage and their co-stimulatory markers CD86 and CD83. Totally, 20 children previously diagnosed as chronic ITP were enrolled in this study and all admitted to hospital with uncontrolled bleeding. Patients received HD-DXM as a single daily dose for 4 days. Blood samples were withdrawn from patients just prior to HD-DXM therapy and on day 5 to evaluate the platelet count and for flowcytometric analysis of DCs. Daily assessment of bleeding severity was performed. The platelet counts significantly increased in patients after 5 days of initiation of therapy compared with platelet count before therapy (p-value = 0. 0002). Control of bleeding observed in (90%), complete response (CR) documented in (50%), response (R) documented in (40%), and no response (NR) documented in (10%) of patients. The time to respond was raging from 1 to 3 days and minor complication recorded in two patients. Both plasmacytoid DCs and myeloid DCs percentage and their expression of co-stimulatory markers, CD86 and CD83 decreased significantly after HD-DXM therapy. Conclusion: short course of HD-DXM as a rescue therapy seems to be an effective alternative emergency treatment for uncontrolled bleeding in chronic ITP children especially in nations with limited resources.

Regulatory B cells (CD19(+)CD38(hi)CD24(hi)) in alloimmunized and non-alloimmunized children with ß-thalassemia major.

BACKGROUND: ß-Thalassemia major (BTM) is considered the most common hemoglobinopathy in Egypt and is one of the major health problems in our locality. MATERIALS & METHODS: We investigated the frequency of B-regulatory cells (CD19(+)CD38(hi)CD24(hi)); (Bregs) among polytransfused alloimmunized and non-alloimmunized children with BTM. The study included 110 polytransfused pediatric patients with ß-thalassemia major. Clinical and transfusion records of all studied patients were reviewed. Indirect antiglobulin test was performed to detect the presence of alloantibodies. We used flow cytometry for detection of CD19(+)CD38(hi)CD24(hi) regulatory B cells. RESULTS: Alloimmunization was detected in 35.5% of thalassemic patients (39/110). The analysis of our data showed a significantly higher frequency of Bregs (CD19(+)CD38(hi)CD24(hi)) in the peripheral blood of both alloimmunized and non-alloimmunized patients as compared to healthy controls. CONCLUSIONS: Our data showed that the frequencies of CD19(+)CD24(hi)CD38(hi) Bregs cells were significantly increased in children with BTM. Our data suggested that Bregs cells could play a role in the clinical course of BTM. The relationship of Bregs to immune disorders in BTM children remains to be determined. Further longitudinal study with a larger sample size is warranted to explore the mechanisms of Breg cells in the disease process in BTM patients.

Circulating Endothelial Cells and Endothelial Progenitor Cells in Pediatric Sepsis.

OBJECTIVES: The aim of the study was to measure the number of circulating endothelial cells (CECs) and circulating endothelial progenitor cells (CEPs) in pediatric patients with sepsis and correlating it with the severity of the disease and its outcome. METHODS: The study included 19 children with sepsis, 26 with complicated sepsis, and 30 healthy controls. The patients were investigated within 48 hours of pediatric intensive care unit admission together with flow cytometric detection of CECs and CEPs. RESULTS: The levels of both CECs and CEPs were significantly higher in patient with sepsis and complicated sepsis than the controls. The levels of CECs were higher in patients with complicated sepsis, whereas the levels of CEPs were lower in patients with complicated sepsis. Comparing the survival and nonsurvival septic patients, the levels of CEPs were significantly higher in the survival than in nonsurvival patients, whereas the levels of CECs were significantly lower in the survival than in nonsurvival patients. Serum albumin was higher in survival than in nonsurvival patients. CONCLUSIONS: Estimation of CECs and CEPs and their correlation with other parameters such as serum albumen could add important information regarding prognosis in septic pediatric patients.

Clinical characteristics and outcome of children stung by scorpion.

UNLABELLED: Scorpion envenomation is a health problem in children in tropical and subtropical regions. The aim of this study was to evaluate demographic and clinical characteristics as well as outcomes in referred children to Assiut University Children Hospital during the year 2012 with a history of scorpion sting. The medical files of these patients were reviewed retrospectively for demographic data, time and site of biting, and clinical manifestations. Laboratory investigations of the patients were reviewed for complete blood count (CBC), liver function tests, creatinine phosphokinase (CPK), lactate dehydrogenase (LDH), arterial blood gases, and serum electrolytes. Results showed 111 children with a history of scorpion sting; 69 males and 42 females with a median age of 5 years. Out of the studied patients, 53.2 % were classified as class III of clinical severity with recorded pulmonary edema in 33.3 %, cardiogenic shock in 46.8 %, and severe neurological manifestations in 22.8 %. Twelve patients (10.8 %) were classified as class II with mild systemic manifestations, and 36 % of the patients were classified as class I with only local reaction. Outcomes of these patients were discharge without sequelae in 55.8 %, discharge with sequelae in 26.1 %, and death in 18.1 %. CONCLUSION: more than half of stung children had a severe clinical presentation and about one fifth died. Aggressive treatment regimens are recommended for such patients to improve the outcome.

Lymphocyte populations and apoptosis of peripheral blood B and T lymphocytes in children with end stage renal disease.

BACKGROUND: End stage renal disease (ESRD) is a worldwide devastating health problem due to its increased prevalence in the population and high association with several pathologic conditions including immunodeficiency, which makes a significant contribution to morbidity and mortality. AIM: The present study aimed at analysis of T and B lymphocyte subpopulation and the detection of flowcytometric apoptosis markers on peripheral B and T lymphocytes in a cohort of children with ESRD. SUBJECTS AND METHODS: A case-control study was conducted on 28 children with ESRD. In addition, 30 age and sex matched healthy children were included as a control group. We used Annexin V-FITC binding assay as a sensitive probe for identifying cells undergoing apoptosis. RESULTS: Circulating neutrophils, T and B lymphocytes were lower in patient group. In addition, apoptotic B and T lymphocytes occurred more frequently in children with ESRD than in the control group. CONCLUSION: Our finding of low numbers of circulating neutrophils, T and B lymphocytes, and increased portion of apoptotic B and T lymphocytes in children with ESRD, may emphasize the fact that these derangements are the main mechanisms responsible for the impairment of the immune system in ESRD children, also it adds to the fact that both cellular and humoral immunity affected in ESRD children. Finally, uremia and increased peripheral lymphocyte apoptosis were the major causes of lymphocyte populations' depletion in our ESRD patients.

Glucocorticoid receptors expression and histopathological types in children with nephrotic syndrome.

UNLABELLED: Abstract Background: Some children with idiopathic nephrotic syndrome (NS) patients fail to respond even when given high dose of steroid. The aim of this study was to assess the GCR expression on the T lymphocytes of children with NS and its relation to the response to steroid and to histopathological type. METHODS: Forty-six pediatric patients with idiopathic NS and 20 age and sex matched apparently healthy children as controls were included. Flow cytometry was employed to determine the percentage of CD3+/GCR+ cells which then correlated with pattern of steroid response. Renal biopsy was done for steroid-dependent and steroid-resistant cases for determination of the underlying histopathological type. RESULTS: The mean percentage of T lymphocyte expression of GCRs (CD3+/GCR) was significantly higher in early steroid responders than in late responders and was slightly lower than the controls. There was a significantly lower GCRs expression in steroid-resistant patients in comparison to early responders, late responders and controls. Renal biopsy showed that most cases of late responders were of the focal segmental glomerulosclerosis (FSGS) type. The mean percentage of lymphocyte expression of GCRs was significantly higher in patients with minimal change disease (MCD) compared to patients with FSGS. CONCLUSION: Evaluation of the expression of intracellular GCRs in T lymphocytes at time of diagnosis of NS can predict the response to steroid therapy and can help in determination of the outcome of NS patients regarding future relapses.

Clinical Signs and Treatment of New-Onset Bone Marrow Failure Associated SARS-CoV-2 Infection in Children: A Single Institution Prospective Cohort Study.

Background: Viral infections can cause direct and indirect damage to hematopoietic stem cells. The objectives of this study were to identify the frequency and severity of aplastic anemia in children infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as well as recognize the response to treatment. Methodology: 13 children with newly diagnosed severe aplastic anemia were enrolled in this prospective clinical trial. Blood samples were obtained from all patients to detect SARS-CoV-2 antibodies, and nasopharyngeal swabs were collected for reverse-transcription Polymerase Chain Reaction to detect SARS-CoV-2 viruses. According to the laboratory results, patients were classified as having SARS-CoV-2 positive antibodies and SARS-CoV-2 negative antibodies. Both groups received combined cyclosporine (CsA) + Eltrombopag (E-PAG). The hematological response, either complete response (CR) or partial response (PR), no response (NR), and overall response (OR) rates of combined E-PAG + CsA treatment after 6 months were evaluated. Results: Four children were recognized to have aplastic anemia and SARS-CoV-2 positive antibodies. Two patients fulfilled the hematological criteria for CR and no longer required transfusion of packed red blood cells (PRBCs) or platelets, and one had PR and was still PRBC transfusion-dependent but no longer required platelet transfusion. The remaining patient showed NR, and he had died before reaching the top of the HSCT waiting list. Moreover, six patients in the SARS-CoV-2 negative antibodies group had CR, while three patients had PR. The difference in ANC, Hg, and platelet counts between both groups was not significant. Conclusion: The SARS-CoV-2 virus is added to several viral infections known to be implicated in the pathogenesis of aplastic anemia. Studies are needed to establish a definitive association and determine whether the response of bone marrow failure to standard therapy differs from that of idiopathic cases.

Platelet antibodies, activated platelets and serum leptin in childhood immune thrombocytopenic purpura.

BACKGROUND/AIM: The aim of this study was to evaluate the levels of platelet-associated antibodies (PAIgG and PAIgM), activated platelets and serum leptin in children with acute immune thrombocytopenic purpura (ITP). METHODS: The study included 40 patients with ITP and 40 healthy age- and sex-matched controls. PAIgG, PAIgM and activated platelet levels were estimated by flow cytometry, and serum leptin levels were estimated by ELISA. RESULTS: Activated platelets and serum leptin were significantly higher in the ITP patients than in the controls. The percentage and mean fluorescence intensity of PAIgG and PAIgM staining were significantly higher in the patients than in the controls. Serum leptin and activated platelet levels in patients with thrombocytopenia of brief duration were significantly lower than those in patients with thrombocytopenia of prolonged duration. The levels of activated platelets, serum leptin and PAIgG were positively correlated, and the levels of serum leptin, activated platelets and platelet counts were negatively correlated. CONCLUSION: The increased levels of activated platelets, serum leptin and platelet-associated antibodies in children with acute ITP suggest that these factors could play a role in ITP pathogenesis. Additionally, activated platelets and serum leptin could have prognostic significance in paediatric acute ITP.

Could the Crosstalk Between Myeloid-Derived-Suppressor Cells and Regulatory T Cells Have a Role in Beta-Thalassemia?

Background: Secondary iron overload, alloimmunization, and increased risk of infection are common complications in patients with transfusion-dependent thalassemia (TDT). Regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) play an essential role in preventing excessive immune response. This research aimed to study the interaction between Tregs and MDSCs in TDT patients and to evaluate the association of these cell types with disease severity. Methods: This case-control study included 26 patients with TDT and 23 healthy, age- and sex-matched controls. All patients were investigated for complete blood count (CBC), serum ferritin, and flow cytometric analysis of peripheral blood to detect Tregs, MDSCs, and MDSC subsets. Results: A significant increase was observed in the frequencies of Tregs and MDSCs, particularly monocytic MDSCs (MO-MDSCs), in TDT patients compared with controls. The frequencies of these cells showed a direct association with ferritin level and total leukocyte count and an inverse association with hemoglobin level. Furthermore, a positive correlation was observed between Tregs and each of the total MDSCs and MO-MDSCs. Conclusions: Levels of Tregs and MDSCs increased in TDT and may probably have a role in suppressing the active immune systems of TDT patients.

Upregulation of Cytotoxic T-cells in pediatric patients with Gaucher disease.

Cytotoxic (CD8) T-cells and natural killer (NK) cells have a significant immune function role. The ongoing stimulation of immunity and the excessive release of proinflammatory cytokines observed in pediatric patients with Gaucher disease (GD) can affect immune cells. Few studies have looked at the proportion of cytotoxic CD8 T-cells and their subsets in children with GD. A prospective case-control study was performed involving twenty pediatric patients with type 1 GD and twenty healthy age-matched controls. All patients received regular enzyme replacement therapy (ERT) for at least 6 months before the study. Complete blood count and flow cytometric analyses of CD8 T, Tc1, Tc2, NK, and NK T-cells were performed. GD patients showed significantly increased of CD8 T, Tc1 and significantly decreased NK cells frequencies when compared to healthy controls. However, no significant difference in Tc2 and NK T-cells was found between the studied groups. GD patients on regular ERT have increased CD8+ T-cell frequencies, predominantly Tc1, together with a reduction in NK cells than in healthy controls. These crucial immunological changes may contribute to some extent to the pathogenesis and the progression of GD.

Genotyping versus phenotyping of non-ABO erythrocyte antigens in patients with the Mediterranean hemopathic syndromes: Effect of transfusion therapy.

The Mediterranean hemopathic syndromes (MHS) are the most prevalent hemoglobinopathies in the Mediterranean basin. Transfusion therapy is the main therapy for these disorders, particularly for severe forms of the disease. Currently, pre-transfusion serological typing of erythrocyte antigens is the standard tool for reducing complications of transfusion in those patients. This study compared genotyping with phenotyping of non-ABO erythrocyte antigens in patients with MHS and assessed the effect of transfusion therapy on their results. One-hundred ninety-eight MHS patients were recruited, screened, and proven negative for allo-antibodies. They were grouped into two groups: (1) 20 newly diagnosed patients with no transfusion history and (2) 178 previously diagnosed patients undergoing transfusion therapy. Patients were interviewed and clinically examined. Full blood count (FBC) and high performance liquid chromatography (HPLC) were done for group 1 only. Genotyping and phenotyping of non-ABO erythrocyte antigens were performed for group 1, and 25 patients out of group 2 were propensity score-matched (PSM) with group 1. Both groups were gender and age matched; 55% and 74% of groups 1 and 2 had major disease, respectively. Insignificant differences were observed between genotyping and phenotyping of non-ABO erythrocyte antigens in group 1, while significant discrepancies and mixed field results were noted in group 2 patients. Discrepancies were obvious with JKa, JKb, and little c antigens. Conclusively, molecular typing is a powerful tool for pre-transfusion testing in chronically transfused MHS patients. This testing reduces incidence of transfusion reactions. JKa, JKb and little c antigens are the most clinically significant non-ABO erythrocyte antigens.

Increase in polymorphonuclear myeloid-derived suppressor cells and regulatory T-cells in children with B-cell acute lymphoblastic leukemia.

Our study aimed to evaluate the levels of MDSCs and Tregs in pediatric B-cell acute lymphoblastic leukemia (B-ALL), their relation to patients' clinical and laboratory features, and the impact of these cells on the induction response. This study included 31 pediatric B-ALL patients and 27 healthy controls. All patients were treated according to the protocols of the modified St. Jude Children's Research Hospital total therapy study XIIIB for ALL. Levels of MDSCs and Tregs were analyzed using flow cytometry. We observed a reduction in the levels of CD4 + T-cells and an increase in both the polymorphonuclear MDSCs (PMN-MDSCs) and Tregs. The frequencies of PMN-MDSCs and Tregs were directly related to the levels of peripheral and bone marrow blast cells and CD34 + cells. Complete postinduction remission was associated with reduced percentages of PMN-MDSCs and Tregs, with the level of PMN-MDCs in this subpopulation approaching that of healthy controls. PMN-MDSCs and Tregs jointly play a critical role in maintaining an immune-suppressive state suitable for B-ALL tumor progression. Thereby, they could be independent predictors of B-ALL progress, and finely targeting both PMN-MDSCs and Tregs may be a promising approach for the treatment of B-ALL.

Role of pretreatment inflammatory indicators in pediatric acute leukemias; where do we stand? A prospective cohort study.

BACKGROUND AND AIM: There is a limited data at the moment regarding the clinical value of inflammatory indices and malnutrition markers in children with acute leukemias. We have examined the usefulness of prognostic nutritional index (PNI), Glasgow prognostic score (GPS), Prognostic Index (PI), monocyte to lymphocyte (MLR), neutrophil to lymphocyte (NLR), and platelet to lymphocyte (PLR) ratios to stratify patients as regards the response to induction therapy correlating them to different prognostic factors. PATIENTS AND METHODS: Children with acute leukemia and without microbial-induced inflammation at the time of diagnosis were prospectively recruited. Preliminary total and differential CBC, c-reactive protein (CRP), serum albumin (ALB) were used to calculate different inflammatory indicators including NLR, MLR, PLR, PNI, GPS, and PI. RESULTS: Higher PNI was significantly more associated to children who achieved remission as compared to those without remission (p< 0.0001). Patients without remission had GPS 1 or 2 compared to GPS 0 or 1 in those who entered remission (p= 0.001). NLR was significantly lower in patients in remission than in those without remission (p= 0.005). Similarly, complete remission was significantly associated to MLR ⩽ 0.45 as compared to MLR > 0.45 (p< 0.0001). CONCLUSION: Pretreatment PNI, GPS, CRP, serum albumin, NLR, MLR, and PLR are remission promising prognostic markers in pediatric acute leukemias, which deserve to be further investigated in large-scale studies.

Assessment of Complement Regulatory Proteins CD55 and CD59 on Erythrocytes in Beta-Thalassemia Major Patients.

This study intended to measure the expression of complement regulatory proteins CD55 and CD59 on RBCs membrane in patients with ß-thalassemia (ß- thal) major in addition to investigate if splenectomy affects their expression pattern. This was a case-control study, participants were allocated in three groups. The study group 1 consisted of ß-thal patients who underwent splenectomy. The study group 2 consisted of ß-thal patients without splenectomy. Group 3 consisted of apparently healthy volunteers as a control group. A significant decrease in CD55 expression in patients' group 1 (46.35±14.61) and group 2 (56.90±9.28) in comparison with group 3 (86.20±9.62) was observed. The percentage of CD55 expression was significantly lower in group 1 patients than group 2 (P=0.01). However, there was no difference in the percentage of CD59 marker expression between any of the patient's groups and the control group. In conclusion, CD55 under-expression on RBCs of ß- thal patients may be considered one of the factors that cause hemolysis in those patients and this complement mediated hemolysis may be one of the underlying causes of organ damage. Additional deficiency of this receptor occurs with splenectomy.