Screening of Dengue virus antiviral activity of marine seaweeds by an in situ enzyme-linked immunosorbent assay

• Published in: PloS one Vol. 7; no. 12; p. e51089
• Main Authors: Koishi, Andrea Cristine, Zanello, Paula Rodrigues, Bianco, Éverson Miguel, Bordignon, Juliano, Nunes Duarte dos Santos, Claudia
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 05-12-2012; Public Library of Science (PLoS)
• Subjects: Adenosine; Algae; Antiviral activity; Antiviral agents; Antiviral Agents - analysis; Antiviral Agents - pharmacology; Antiviral Agents - therapeutic use; Assaying; Biology; Cell Death - drug effects; Cell Line, Tumor; Clinical isolates; Cytotoxicity; Dengue; Dengue - drug therapy; Dengue fever; Dengue virus; Dengue Virus - drug effects; Dengue Virus - physiology; Drug discovery; Drug Evaluation, Preclinical; Enzyme-linked immunosorbent assay; Enzyme-Linked Immunosorbent Assay - methods; Genomes; Health aspects; Humans; Immunoassay enzymes; Infection; Infections; Internalization; Medical research; Medical screening; Medicine; Natural products; Phaeophyceae; Public health; Reliability aspects; Reproducibility of Results; Seawater - chemistry; Seaweed - chemistry; Seaweeds; Serotypes; Statistical analysis; Vaccines; Vector-borne diseases; Viral diseases; Virus Internalization - drug effects; Viruses; Brazil; United States > US
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0051089

Dengue is a significant public health problem worldwide. Despite the important social and clinical impact, there is no vaccine or specific antiviral therapy for prevention and treatment of dengue virus (DENV) infection. Considering the above, drug discovery research for dengue is of utmost importance; in addition natural marine products provide diverse and novel chemical structures with potent biological activities that must be evaluated. In this study we propose a target-free approach for dengue drug discovery based on a novel, rapid, and economic in situ enzyme-linked immunosorbent assay and the screening of a panel of marine seaweed extracts. The in situ ELISA was standardized and validated for Huh7.5 cell line infected with all four serotypes of DENV, among them clinical isolates and a laboratory strain. Statistical analysis showed an average S/B of 7.2 and Z-factor of 0.62, demonstrating assay consistency and reliability. A panel of fifteen seaweed extracts was then screened at the maximum non-toxic dose previously determined by the MTT and Neutral Red cytotoxic assays. Eight seaweed extracts were able to reduce DENV infection of at least one serotype tested. Four extracts (Phaeophyta: Canistrocarpus cervicornis, Padina gymnospora; Rhodophyta: Palisada perforate; Chlorophyta: Caulerpa racemosa) were chosen for further evaluation, and time of addition studies point that they might act at an early stage of the viral infection cycle, such as binding or internalization.