Fadwa Said

Intrafamilial transmission of hepatitis C infection in Egyptian multitransfused thalassemia patients.

OBJECTIVE Detecting the current prevalence of hepatitis C virus (HCV) among Egyptian multitransfused thalassemic patients and evaluating the risk of its transmission within their family members. METHODS Multitransfused Egyptian thalassemia patients (n = 137) were tested for HCV infection. Household contacts of positive members were compared with household contacts of HCV-negative patients. Antibodies to HCV were detected by enzyme immunoassay. Antibody-positive cases were retested for viral load using reverse transcriptase polymerase chain reaction. HCV genotyping was performed on positive samples of the patients and the positive household contacts. RESULTS In all, 34.4% of patients (n = 47) were positive for HCV antibodies and RNA. The study of 24 families of HCV-positive patients showed 14 affected family members (19.2%). In 27 families of HCV-negative patients, four family members were affected (4.9%). HCV genotyping of seven families was similar in both patients and their family members. CONCLUSION Our results support the role of intrafamilial transmission in the spread of HCV.

Indoleamine 2,3-dioxygenase and regulatory T cells in acute myeloid leukemia

Background and objectives: The microenvironment of acute myeloid leukemia (AML) is suppressive for immune cells. Regulatory T cells (Tregs) have been recognized to play a role in helping leukemic cells to evade immunesurveillance. The mesenchymal stem cells (MSCs) are essential contributors in immunomodulation of the microenvironment as they can promote differentiation of Tregs via the indoleamine 2,3-dioxygenase (IDO) pathway. The aim of the present work was to evaluate the expression of IDO in bone marrow derived MSCs and to study its correlation to percentage of Tregs. Methods: Thirty-seven adult bone marrow samples were cultured in appropriate culture medium to isolate MSCs. Successful harvest of MSCs was determined by plastic adherence, morphology, and positive expression of CD271 and CD105; negative expression of CD34 and CD45 using flowcytometry. MSCs were examined for IDO expression by immunocytochemistry using anti-IDO monoclonal antibody. CD4+ CD25+ cells (Tregs) were measured in bone marrow samples by flowcytometry. Results: MSCs were successfully isolated from 20 of the 37 bone marrow samples cultured. MSCs showed higher expression of IDO and Tregs percentage was higher in AML patients compared to control subjects (P = 0.002 and P < 0.001, respectively). A positive correlation was found between IDO expression and Tregs percentage (P value = 0.012, r = 0.5). Conclusion: In this study, we revealed an association between high IDO expression in MSCs and elevated levels of Tregs which could have an important role in the pathogenesis of AML, providing immunosuppressive microenvironment.