ABSTRACT
Background and Objectives. Interactions between sickle cells involving CD 49d, CD36, and the vascular endothelium may initiate vasoocclusion leading to acute painful episodes and multiple organ failure. Materials and Methods. We selected 60 SS patients who had never been treated by hydroxyurea. We performed a total blood count. We identified with immunophenotyping by flow cytometry total reticulocytes their distribution according to the degree of maturity (mature, intermediate, very immature) and CD 36(+) and CD 49d(+) antigens. Stress reticulocytes corresponded to the sum of intermediate and immature cells. Results. Subjects in crisis had more total reticulocytes and very immature reticulocytes than subjects in stationary phase (P < 0.05). During the crisis, total CD 36(+) reticulocytes (214 870 ± 107 584/ µ L versus 148 878 ± 115 024/ µ L; P < 0.05) and the very immature CD 36(+) reticulocytes (28.9 ± 7.9% versus 23.0 ± 6.4%; P < 0.05) increased. The clinical status had no impact on CD 49d(+) reticulocytes. Conclusion. The rates of stress reticulocytes in general and those expressing CD 49d and CD 36 were very high. The clinical status had an influence on CD 36(+) reticulocytes. The expression of adhesion molecules is only one of the parameters involved in sickle cell disease crisis.
ABSTRACT
BACKGROUND: In Côte d'Ivoire, acute leukemias account for 12.5% of hematological malignancies. Acute leukemias are due to an anomaly of the stem cell characterized among other things by the expression of CD34(+) CD38(-) surface markers. This CD34(+) CD38(-) phenotype as well as other factors such as tumor syndrome, high leukocytosis and blasts are considered as important factors of poor prognosis. We therefore proposed to investigate the prognostic value of the expression of CD34(+) CD38(-) markers in acute leukemias in Abidjan. METHODS: We selected 23 patients aged 33 years on whom we performed Complete Blood Count, bone marrow aspiration and immunophenotyping. To search for myeloperoxydase, smears of blood or bone marrow were stained with benzidine and revealed by the use of Hydrogen peroxide. Acute leukemias were then identified and distributed using the score proposed by the European Group for the Immunological characterization of Leukemias. The definitive diagnosis was made by combining morphological characters that serve as the basis for the French-American-British classification as well as cytochemical and immunophenotypic characters. RESULTS: According to the cytological and immunophenotypic classifications, the acute lymphoid leukemia 2 and B IV predominated. 52.2% (12/33) of patients were CD34(+) CD38(-). This phenotype was found in almost all cytological immunophenotypic types. The medullary invasion by blasts (reflection of the tumor mass) of the total sample of CD34(+), CD34(+) CD38(-) patients and those not expressing CD34(+) was respectively 79.4%, 81.25%, 83.3% and 74.8%. CONCLUSION: There was therefore no correlation between medullary blasts and the expression of CD34(+) CD38(-). To the factors we selected it would have been necessary to associate the study of cytogenetic and molecular anomalies to better understand the role of CD34(+) CD38(-) phenotype, concerning prognosis.