Issues in Biological Sciences and Pharmaceutical Research
Vol.6(1),pp. 8-16, August 2018
Available online at https://www.journalissues.org/IBSPR/
Author(s) retain the copyright of this article. Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License.
Original Research Article
Polymorphism and allelic variation of domain I of the Plasmodium falciparum apical membrane antigen-1 (ama1) gene and status of Plasmodium vivax infections in parasitized isolates from Buea, Cameroon
Dieudonné Lemuh Njimoh1*, Marcel Moyeh Nyuylam1, Brice Tcheubousou Meulah1, Daniel Nnak Bangwen1 and Carline Nsenga Vakam2
1Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, P.O.Box 63 Buea, South West Region, Cameroon.
2Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O.Box 63 Buea, South West Region, Cameroon.
*Corresponding Author Email: njimoh.dieudonne(at)ubuea.cm
Tel: +237 672 11 05 07
Malaria still remains a scourge of humanity despite the significant impact of the currently used drugs and vector control measures. Only a very successful vaccine can ensure a long term effective control of this disease. This study was aimed at assessing the (i) antigenic variability of domain I of the AMA1 vaccine candidate gene in falciparum isolates from Buea, Cameroon (ii) status of Plasmodium vivax infections in this study area using nPCR and RFLP. Parasitized blood samples were collected from 139 adults/children with uncomplicated malaria for microscopy and genetic analyses by nPCR and RFLP. 113 (81.9%) of the participants were febrile and 25 (18.1%) afebrile. While Fever was directly associated with parasitaemia (p=0.001) haemoglobin concentrations were inversely correlated to the latter (p=0.05, r= -0.032). Digestion of the isolated AMA1 fragments with Mse1, Bfcu1 and Ssp1 revealed the presence of the K1, HB3 and 3D7 alleles respectively in 15%, 9% and 3.4% of the samples analyzed. These sites were absent in 71.6% of the samples. One Plasmodium vivax isolate was detected in 138 samples. Our findings show that the P. falciparum AMA1 gene from malaria parasites circulating in Buea is highly polymorphic with the three major allelic forms present. Plasmodium vivax infections are almost inexistent in Buea. The results herein obtained will be relevant for AMA1-based malaria vaccine development that will be globally effective as well as for the National malaria treatment guidelines.
Key words: Malaria, Plasmodium falciparum, Plasmodium vivax, apical membrane antigen, vaccine candidates, AMA1 alleles, polymorphism