Towards Generation of Transplastomic Tobacco, Expressing a 35 kdaProtein as an Antigen: A Step towards Affordable Plant made Vaccine against Mycobacterium

Abstract

Plants offer the unique opportunity to be engineered as bio-factories for the production of different antigens, enzymes and vaccines. Recently chloroplast transformation has gained strong interest in the field of Plant Made Vaccines (PMVs). An efficient cross-protective antigen against Mycobacterium is a 35 kDa protein encoded by mmpI gene in Mycobacterium leprae. Although vaccines against Mycobacterium infections are commercially available, they are neither affordable nor available for patients in resource poor countries. Thus, alternative cost-effective vaccine production approaches need to be developed. In the current study we have reported the possibility to generate transplastomic tobacco carrying 35-kDa protein conferring cross-protective resistance against two different pathogens Mycobacterium leprae and Mycobacterium avium. The mmpI gene along with an adjuvant Lymphotoxin-beta (LTB) was successfully transformed into tobacco chloroplast by the Polyethylene glycol (PEG) mediated transformation method. The PEG transformation method provides an effective and cost efficient transformation procedure and can easily be adopted in resource-poor countries in comparison to biolistic transformation. Integration of LTB and mmpI genes into transplastomic plant genome was confirmed by PCR analysis. In total four transplastomic lines were generated which were healthy and normal. All plants had regular growth pattern, they were able to reach maturity and produce viable seeds. Taken together, the data presented in the study is a valuable step forward to pave the way in the development of cost effective and easily administrable PMVs for resource-poor countries.