Abstract
BackgroundAnti-filarial IgG4 antibody has been shown to be a good marker for detection of lymphatic filaria infection. Previous studies demonstrated that anti-filarial IgG4 assay using BmR1 recombinant antigen was highly specific and sensitive for detection of brugian filariasis. For bancroftian filariasis, an equivalent assay employing recombinant antigen expressed from the ORF of SXP1 gene has been reported. In order to detect infections by all species of lymphatic filarial, BmR1 and BmSXP recombinant antigens were employed in the development of a pan LF-ELISA.MethodsBmR1 was previously produced while BmSXP recombinant antigen was produced by cloning the ORF of SXP1 gene from a Brugia malayi cDNA library, followed by expression in a bacterial expression system. Subsequently, each of the purified recombinant antigens (BmR1 and BmSXP) and mixture of different ratios of the two antigens (1:1, 2:1 and 1:2) were tested using IgG4-ELISA with various categories of infection and normal human serum samples.ResultsThe results showed that both recombinant antigens were highly specific (99%–100%). For detection of brugian filariasis, BmR1 antigen alone and the mixture of BmR1 with BmSXP (1:1) gave 98% sensitivity; while BmSXP antigen alone showed 84% sensitivity. For detection of bancroftian filariasis, BmSXP antigen was more sensitive (95%) than assays using either BmR1 or mixtures of the two recombinant antigens.ConclusionA sensitive and specific pan LF-ELISA for detection of lymphatic filariasis was successfully developed using two adjacent wells, each separately coated with BmR1 and BmSXP.
Highlights
Anti-filarial IgG4 antibody has been shown to be a good marker for detection of lymphatic filaria infection
The 'shortlisted' antigen candidates selected for best sensitivity and specificity for detection of brugian and bancroftian filariasis were BmR1, BmSXP, and 1:1 mixture of the two antigens
All antigen preparations gave excellent results i.e. 99– 100% specific. Since both BmR1 and BmSXP seemed to be sensitive (98% and 84% respectively) in detecting anti-filarial IgG4 in brugian filariasis patients, comparison of the degree of reactivities of BmR1 and BmSXP to serum samples from B. malayi patients were made by comparing the mean optical density (OD) obtained by each of the recombinant antigens using 30 serum from B. malayi microfilaraemic patients which reacted with both antigens
Summary
Anti-filarial IgG4 antibody has been shown to be a good marker for detection of lymphatic filaria infection. Previous studies demonstrated that anti-filarial IgG4 assay using BmR1 recombinant antigen was highly specific and sensitive for detection of brugian filariasis. An equivalent assay employing recombinant antigen expressed from the ORF of SXP1 gene has been reported. In order to detect infections by all species of lymphatic filarial, BmR1 and BmSXP recombinant antigens were employed in the development of a pan LF-ELISA. Human lymphatic filariasis (LF) is caused by three species of tissue dwelling filaria nematodes namely Wuchereria bancrofti, Brugia malayi and Brugia timori. Lymphatic filariasis causes a spectrum of clinical and sub-clinical manifestations which include recurrent fever, adenolymphangitis, renal and lymphatic damage, chyluria, hydrocoele and elephantiasis. A WHO initiated Global Program for Elimination of Lymphatic Filariasis (GPELF) is ongoing and the target year is 2020 [2]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
