Promising application of monoclonal antibody against chikungunya virus E1-antigen across genotypes in immunochromatographic rapid diagnostic tests

Abstract

Background Three different genotypes of chikungunya virus (CHIKV) have been classified: East/Central/South African (ECSA), West African (WA), and Asian. Previously, a rapid immunochromatographic (IC) test detecting CHIKV E1-antigen showed high sensitivity for certain ECSA-genotype viruses, but this test showed poor performance against the Asian-genotype virus that is spreading in the American continents. We found that the reactivity of one monoclonal antibody (MAb) used in the IC rapid diagnostic test (RDT) is affected by a single amino acid substitution in E1. Therefore, we developed new MAbs that exhibited specific recognition of all three genotypes of CHIKV. Methods Using a combination of the newly generated MAbs, we developed a novel version of the IC RDT with improved sensitivity to Asian-genotype CHIKV. To evaluate the sensitivity, specificity, and cross-reactivity of the new version of the IC RDT, we first used CHIKV isolates and E1-pseudotyped lentiviral vectors. We then used clinical specimens obtained in Aruba in 2015 and in Bangladesh in 2017 for further evaluation of RDT sensitivity and specificity. Another alphavirus, sindbis virus (SINV), was used to test RDT cross-reactivity. Results The new version of the RDT detected Asian-genotype CHIKV at titers as low as 10^4 plaque-forming units per mL, a concentration that was below the limit of detection of the old version. The new RDT had sensitivity to the ECSA genotype that was comparable with that of the old version, yielding 92% (92 out of 100) sensitivity (95% confidence interval 85.0–95.9) and 100% (100 out of 100) specificity against a panel of 100 CHIKV-positive and 100 CHIKV-negative patient sera obtained in the 2017 outbreak in Bangladesh. Conclusions Our newly developed CHIKV antigen-detecting RDT demonstrated high levels of sensitivity and lacked cross-reactivity against SINV. These results suggested that our new version of the CHIKV E1-antigen RDT is promising for use in areas in which the Asian and ECSA genotypes of CHIKV circulate. Further validation with large numbers of CHIKV-positive and -negative clinical samples is warranted. (323 words).

Chikungunya Manifestations and Viremia in Patients Who Presented to the Fever Clinic at Bangkok Hospital for Tropical Diseases During the 2019 Outbreak in Thailand

“…Though the illness is self-limiting, infection results in increased morbidity and atypical manifestation, often with increased severity and fatalities (36,37,(56)(57)(58)(59)(60)(61)(62)(63). Chikungunya virus causes similar clinical manifestations during the acute phase that could mimic other arboviruses, and there are no widely available point-of-care rapid diagnostics (43,64,65). For these reasons, clinicians working in endemic regions and those treating returning travelers are challenged with diagnosing chikungunya infection (40,(66)(67)(68).…”

“…The prototype kit was developed at Mahidol-Osaka Center for Infectious Diseases, and the details of the immunochromatography kit have been described previously, including the validation of the kit performance (41)(42)(43). Briefly, left-over serum from routine investigation performed at the Fever Clinic was obtained from the hospital central laboratory.…”

“…To overcome this obstacle, researchers at the Mahidol-Osaka Center for Infectious Diseases at Mahidol University in Thailand, in collaboration with the Department of Viral Infections at Osaka University in Japan, have developed a novel prototype rapid point-of-care immunochromatography test kit that identifies suspected chikungunya cases based on detection of the E1 antigen (41,42). This prototype's performance and updated test kits have been validated using clinical specimens from different parts of the world (43,44). This new diagnostic breakthrough in translational research is promising for easy and quick detection of suspected cases of chikungunya infections during outbreaks.…”

A Novel Sub-Lineage of Chikungunya Virus East/Central/South African Genotype Indian Ocean Lineage Caused Sequential Outbreaks in Bangladesh and Thailand

“…All viruses analyzed in the present study are listed in Table 1 . Twenty acute febrile cases that were serum-positive for CHIKV by real-time RT-PCR were collected at the Apollo Hospitals Dhaka in Dhaka city, Bangladesh, in 2017 [ 11 , 16 ]. This study proposal was approved by the Research and Ethics Committee of Apollo Hospitals Dhaka (ERC 16/2018–3).…”

Post–Chikungunya Virus Infection Musculoskeletal Disorders: Syndromic Sequelae after an Outbreak

“…The patient's medical chart was reviewed retrospectively to extract the clinical data, and the patient was closely followed up until resolution of her symptoms. We used a prototype lateral-flow immunochromatography rapid point-of-care test kit to detect the CHIKV envelope protein 1 (E1) antigen, which was subsequently confirmed via real-time RT-PCR analysis [21,22]. Other serologic tests included anti-CHIKV immunoglobulin M (IgM) and immunoglobulin G (IgG) (SD Biosensor, Inc. Gyeonggi-do, Korea), dengue non-structural protein 1 (NS1) antigen (Biosynex, Swiss S.A, Fribourg, Switzerland), and anti-DENV IgM and IgG (S, Bioline, Sankt Ingbert, Germany).…”