In vitro assessment of a dendritic cell engineered therapeutic vaccine for gastro-intestinal Malignancies

A Bhargava, D Mishra, S Varshney, S Banerjee and P K Mishra

: J Bioengineer & Biomedical Sci

Abstract :

BiotechnologyBackground: Dendritic cell (DC) engineered therapeutic vaccine aims to generate immunologic targeting of cancer cells through induction of an effective response specific for antigens selectively expressed by the tumor cells. Higher ability to selectively eliminate the rapidly mutating transformed cells by recognizing multiple antigens with limited scope of unintended tissue damage provides apoptotic tumor-cell lysate an unique advantage to be exploited for DC based immunotherapy.Materials & Methods: Apoptotic cell lysate from Hep G2 (human hepatocellular carcinoma), HT-29 (human colon adenocarcinoma), MIAPaCa-2 (human pancreatic carcinoma) cultured cells and surgical resected specimens from human liver, pancreas and colon tumors were pulsed with allogeneic DCs for in-vitro assessment of immunogenicity. Quantitative uptake of apoptotic cell lysate was documented by flow cytometry and internalization by the DCs was studied using spectral bio-imaging. Ability of antigen-pulsed DCs to stimulate T lymphocytes through BrdU labeling and TH1/TH2 cytokine response was evaluated using multiples cytometric bead array assay.Results: Our results indicate that apoptotic lysate from cancer cells and excised tumor tissues significantly foster a TH1 cell mediated immune response. Flow cytometric and spectral bio-imaging studies showed convincing uptake of the tumor lysate by DCs suggesting efficient endocytosis. Stimulation with lysate-pulsed DCs also elicited a strong proliferative response when co-cultured with T cells.Discussion: The findings of the current investigation suggest that an engineered vaccine generated from apoptotic tumor cell lysate pulsed DCs could be an enabling step in designing a clinically-translatable, inexpensive, highly-efficient, and personalized immunotherapy for gastrointestinal malignancies.Acknowledgements: The authors are thankful to Council of Scientific & Industrial Research (CSIR), Government of India, New Delhi for financial support