Research Articles

      Abstract    

        

EFFECT OF VARIED PBMC CONCENTRATION AND RESTING TIME, ON INTERFERON-GAMMA(INF-Γ) ELISPOT ASSAY OUTCOME, USING PLASMODIUM FALCIPARUM AMA 1 SELECTED PEPTIDES

Nfor Omarine Nlinwe

 

ABSTRACT: ELiSpot assays can be used to generate consistent results when standardized assay procedures are utilized. Some of the optimal conditions includes peripheral blood mononuclear cell (PBMC) resting and test cell concentration. INF-γ EliSpot assays were performed with PBMCs collected from three study subjects, inorder to determine the effects of varied cell concentrations and resting times on the assay outcome. PBMCs were tested at 2 × 106 cells/ml and at 3 × 106 cells/ml and for each cell concentration, resting was done for 6hrs and 12hrs. The number of spots per well which was estimated using an automated ELISpot plate reader was exported to Microsoft Excelandconverted to spots forming cells per million PBMCs. The results show that, variation in PBMC concentration and resting time, did not necessarily produce an expected linear conversion from spots counts to spots forming cells per million.

 

KEY WORDS: IFN-γ ELISPOT , Plasmodium falciparum, PBMC

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