Analysis of lactate dehydrogenase gene polymorphisms and prediction of B cell epitopes in four human Plasmodium species
10.16250/j.32.1374.2021026
- VernacularTitle:人体疟原虫乳酸脱氢酶基因多态性及B细胞表位预测
- Author:
He-rong HUANG
1
;
Ying DONG
2
;
Yan DENG
2
;
Yan-chun XU
2
;
Meng-ni CHEN
2
;
Yan LIU
2
;
Cang-lin ZHANG
2
Author Information
1. Department of Basic Medical Sciences, Clinical College of Anhui Medical University, Hefei, Anhui 230031, China
2. Yunnan Institute of Parasitic Diseases Control, Yunnan Centre of Malaria Research, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Pu’er, Yunnan 665000, China
- Publication Type:Journal Article
- Keywords:
Human Plasmodium;
Lactate dehydrogenase;
Gene polymorphism;
B-cell epitope;
Epitope prediction
- From:
Chinese Journal of Schistosomiasis Control
2022;34(1):28-35
- CountryChina
- Language:Chinese
-
Abstract:
Objective To analyze the polymorphism of Plasmodium lactate dehydrogenase (pLDH) gene and predict B-cell epitopes in pLDH peptides in four species of human malaria parasites. Methods The blood samples and epidemiological characteristics were collected from malaria cases in Yunnan Province registered in the National Notifiable Disease Report System. The pLDH genes of four human Plasmodium species were amplified using nested PCR assay and sequenced. The polymorphisms of pLDH genes was analyzed using the software MEGA version 7.0.26 and DnaSP version 5.10, and the B-cell epitopes were predicted in pLDH peptides using the Immune Epitope Database (IEDB). Results The sequences of P. vivax LDH (PvLDH), P. falciparum LDH (PfLDH), P. ovale LDH (PoLDH) and P. malariae LDH (PmLDH) genes were obtained from 153, 29, 17 and 11 blood samples from patients with P. vivax, P. falciparum, P. ovale and P. malariae malaria, respectively, which included 15, 2, 4 and 2 haplotypes and had a nucleotide diversity (π) of 0.104. A high level of intra-species differentiation was seen in the PoLDH gene (π = 0.012), and the π values were all < 0.001 for PvLDH, PfLDH and PmLDH genes. Active regions of B-cell antigen were predicted in the pLDH peptide chain of four human malaria parasites, of 4 to 5 in each chain, and the activity score was approximately 0.430. Among these peptide chains, the “86-PGKSDKEWNRD-96” short-peptide was a B-cell epitope shared by all four species of human malaria parasites, and the “266-GQYGHS (T)-271” short-peptide was present in PvLDH and PoLDH peptide chains, while “212-EEVEGIFDR-220” was only found in the PvLDH peptide chain, and “208-LISDAE-213” was only seen in the PfLDH peptide chain. Conclusions The PoLDH gene polymorphism may be derived from the weak negative purification selection, while PvLDH, PfLDH and PmLDH genes may maintain a relatively conservative state. There may be two B-cell epitopes “212-EEVEGIFDR-220” and “208-LISDAE-213” in the proximal region of the C terminal in the pLDH peptide chain, which is feasible to differentiate between P. vivax and P. falciparum infections.
