In Vitro Responses of Human Peripheral Blood Mononuclear Cells to Candidate Vaccine Based on the M2e Peptide of Influenza Virus

Due to its rapid mutation, the influenza virus A become pandemic in many countries. Particularly in Indonesia, the H5N1 cases is one of the highest with the death rate is almost 90 %. An efficient vaccine to address the problem has not been discovered, and as type A influenza virus continues to mutate. The current study focuses on developing a conserved epitope-based universal influenza virus vaccine, M2e. One of them is M2e2-16-K-P25 which is the 2nd to 16th sequence M2e epitope connected to the helper T cell epitope P25 via lysine residue (K). The purpose of this study is to determine the formulation and incubation period of optimum candidate influenza virus vaccine universal epitope M2e in triggering Peripheral Blood Mononuclear Cells (PBMC) to produce the cytokines interleukin-4 (IL-4) and interferon- (IFN-). PBMC was isolated by a gradient centrifugation method with Ficoll-Hypaque 1077, then PBMC was cultured in complete growth medium and stimulated by a vaccine candidate formulation. The concentrations of IL-4 and IFN- were measured by the Enzyme-Linked Immunosorbent Assay (ELISA) method, and cell viability testing was performed by addition of 3- [4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide (MTT). The results showed that the concentration of 2 nmol with the addition of alhydrogel during the incubation time of 120 hours, was the formulation of vaccine candidate and the optimum incubation time in triggering PBMC to produce IFN- with the concentration of 328 pg / mL, but IL-4 production tended not to be provided. Cell viability test with MTT showed values that were aligned with ELISA results, which at 120 hours incubation period increased cell proliferation by 500 %.