Abstract
Oral delivery of vaccines is able to induce systemic as well as mucosal immune responses but is largely inefficient due to intestinal degradation and impermeable barrier property of GIT of administered antigen. Efforts are being made to develop a safe and effective oral vaccination by offering resistant against acidic and enzymatic degradation before reaching to the target site. Several strategies are developed to target antigen to the gut associated lymphoid tissue (GALT) present in the intestine where antigen-specific immune responses are initiated. This review discusses various technologies and targets for antigen delivery to induce protective immunization by oral vaccine.