MSPTM 2019 Annual Scientific Conference
13 - 14 March 2019
InterContinental Kuala Lumpur

Abstract

Title

A single amino acid change in nsP4 of Chikungunya virus confers fitness advantage in human cell lines but not in Ae. albopictus

Type
E-Poster Presentation Competition for Student
Theme
Scaling Up Efforts in Tropical Disease and Vector Control through Evidence-Based Research
Topic
Medical Microbiology & Parasitology

Authors

Main Author
Jolene Yin Ling Fu1
Presenting Author
Jolene Yin Ling Fu1
Co-Author
Jamal I-Ching Sam1
Yoke Fun Chan1
Indra Vythilingam2
Wan Yusoff bin Wan Sulaiman2
Andres Merits3
Hui Vern Wong1

Authors' Institution

Department / Institution / Country
Medical Microbiology / Faculty of Medicine, Universiti Malaya / Malaysia1
Parasitology / Faculty of Medicine, Universiti Malaya / Malaysia2
Institute of Technology / University of Tartu / Estonia (Eesti)3
Content
Abstract Content
The adaptation of chikungunya virus (CHIKV) to a secondary vector Aedes (Ae.) albopictus has been associated with several large-scale epidemics since 2004. This adaptation was caused by the E1-A226V mutation that provides better infectivity and dissemination in Ae. albopictus. In the 2008-2009 Malaysia outbreak, a dominant mutation (R82S) was detected in non-structural protein 4 (nsP4) of CHIKV strain from the ECSA Indian sublineage (IL). Phylogenetic analysis showed this nsP4-R82S mutation has since spread across Southeast Asia. To determine whether this amino acid substitution provides an advantageous selection which may have contributed to the epidemic, CHIKV fitness were compared in Ae. albopictus and in human cell lines. Using viral infectious clones of the ECSA genotype from IL, it was demonstrated that viral infectivity, dissemination and transmission in Ae. albopictus were not affected by the mutation. To determine whether selection occurs in a competitive environment, Ae. albopictus mosquitoes and human (RD and HEK-293T) cells lines were co-infected with nsP4-82S and the nsP4-82R viruses at equal titres. Results showed wild-type nsP4-82R has similar fitness with nsP4-82S in Ae. albopictus but was rapidly outcompeted by nsP4-82S in human cell lines. These observations demonstrated that the nsP4-R82S mutation does not confer fitness advantage in Ae. albopictus as was the case with E1-A226V, but may instead provide a selective advantage in humans.
Keywords: chikungunya virus; nsP4; Ae. albopictus; Southeast Asia
Requires Audio or Video system for Presentation?: No