EVALUATION OF MICRORNA-451, VASCULAR CELL ADHESION MOLECULE-1, SOLUBLE P-SELECTIN, CD4 AND CD36 IN SICKLE CELL DISEASE SUBJECTS IN BAYELSA STATE, NIGERIA.

Introduction: Sickle cell disease (SCD) is an autosomal recessive inherited haemoglobin disorder caused by a β-globin gene mutation and characterised by haemolysis, inflammation, endothelial activation, abnormal cellular adhesion and vaso-occlusion. MicroRNA-451 (miRNA-451), vascular cell adhesion molecule-1 (VCAM-1), soluble P-selectin, CD4 and CD36 are involved in erythroid regulation, vascular adhesion and immune responses. 
Objective: This study evaluated the relative expression of miRNA-451 and the levels of VCAM-1, soluble P-selectin, CD4 and CD36 among HbSS, HbAS and HbAA subjects in Bayelsa State, Nigeria and determined the relationships among these parameters in Bayelsa State, Nigeria. 
Study design: This comparative cross-sectional study included 186 participants from different medical facilities across Bayelsa state with the eight (8) Local Government Area: 62 each with HbSS group as case study and HbAS and HbAA groups as control Subjects. Subjects were within the aged 2 - 51 years males and females subjects.
Methodology: Haemoglobin genotype was determined by alkaline haemoglobin electrophoresis. Plasma VCAM-1 and soluble P-selectin were measured by enzyme-linked immunosorbent assay, and CD4 and CD36 were measured by flow cytometry. Whole-blood miRNA-451 was quantified by reverse-transcription quantitative polymerase chain reaction. 
Statistical tools: Data were analysed using SPSS version 21.0.
Result: Group means were compared using one-way analysis of variance followed by the Waller–Duncan multiple-range test. Correlation coefficients were calculated for the combined sample and separately within each genotype group. Statistical significance was set at p<0.05. Mean relative miRNA-451 expression was higher in HbSS participants than in HbAS and HbAA subjects. VCAM-1 concentration was higher in HbSS than in HbAS and HbAA subjects. Soluble P-selectin was higher in HbSS than in HbAS and HbAA subjects. CD4 counts did not differ significantly among groups. CD36 values were higher in HbSS than in HbAS and HbAA subjects. In the combined sample, miRNA-451 correlated positively with VCAM-1, soluble P-selectin and CD36. VCAM-1 correlated with soluble P-selectin and CD36 and soluble P-selectin correlated with CD36 at p<0.01. No significant correlations were observed within individual genotype groups. Haemoglobin SS participants had higher miRNA-451, VCAM-1, soluble P-selectin and CD36 values than HbAS and HbAA participants, whereas CD4 counts were comparable. These findings describe differences in erythroid, endothelial and cellular adhesion-related parameters among the studied genotype groups but do not establish causal relationships.