CHIKV Is a Cytopathic Virus

<div><p>(A) CHIKV-infected dying cells. At 24 h after CHIKV infection, HeLa cells were fixed, stained with anti-CHIKV antibodies, and analyzed by confocal microscopy.</p> <p>(B) Viability of cell cultures. HeLa cells were infected with CHIKV at the indicated moi. After 24 h pi, cell viability was measured in a colorimetric assay (MTT cell viability test). Data are mean ±SD of triplicates and representative of five independent experiments;</p> <p>(C) Apoptosis of CHIKV-infected cells. At 24 h pi (moi 10), HeLa cells were doubly stained with anti-active caspase-3 and anti-capsid antibodies and analyzed by flow cytometry. The percentage of caspase-3 positive and negative cells among CHIKV positive cells is depicted. Similar results were obtained with another marker of apoptosis (TUNEL, not shown). Data are representative of three independent experiments.</p> <p>NI, noninfected cells.</p>