Role of Flow Cytometry in the Diagnosis of Chronic Granulomatous Disease: the Egyptian Experience

• DOI: 10.1007/s10875-016-0297-y
• Publication Date: 2016-05-24T14:15:35Z
• Authors: Rabab El Hawary; Safa Meshaal; Caroline Deswarte; Nermeen Galal; Mahitab Abdelkawy; Radwa Alkady; Dalia Abd Elaziz; Tomas Freiberger; Barbora Ravcukova; Jiri Litzman; Jacinta Bustamante; Jeannette Boutros; Taghrid Gaafar; Aisha Elmarsafy
• Keywords: Male; 0301 basic medicine; Genotype; Neutrophils; Infant; NADPH Oxidases; Flow Cytometry; Granulomatous Disease, Chronic; Immunophenotyping; 3. Good health; 03 medical and health sciences; Risk Factors; Child, Preschool; Mutation; Humans; Egypt; Female; Child; Biomarkers; NADP

Chronic granulomatous disease (CGD) is an inherited mutational defect in any of the NADPH oxidase complex, CYBB (gp91-phox), NCF1 (p47-phox), CYBA (p22-phox), NCF2 (p67-phox), or NCF4 (p40-phox) leading to inability of phagocytes to perform effective respiratory burst and thus diminished killing of bacteria and fungi. The identification of defective proteins aids in establishing a diagnosis prior to genetic analysis, which is rather labor-intensive, expensive, and time-consuming.The present study aims at assessing the NADPH proteins by performing the intracellular staining with specific monoclonal antibodies and their assessment on flow cytometry. The use of flow cytometry is less laborious and faster to perform than western blot. It also confirms the diagnosis of CGD and detects the affected components allowing proper management of patients.Twenty-eight patients from 25 different kindred, clinically suspected as CGD were recruited in Egypt. Dihydrorhodamine test was performed to confirm the diagnosis of the patients. Intracellular staining of NADPH components using specific monoclonal antibodies was performed followed by flow cytometric analysis.The present study revealed that the most common defective protein in our cohort is p22-phox, found in 13 patients (46.4 % of cases) followed by p47-phox in 8 patients (28.6 %), gp91-phox in 5 patients (17.9 %), and finally p67-phox in 2 patients (7.1 %).In countries with limited resources and yet large number of CGD patients, the analysis of the defective proteins by flow cytometry is an optimum solution for confirming the diagnosis and is a step for targeted sequencing in families seeking prenatal diagnosis.