1. Genetic engineering is applied in the development of these vaccines. 

2. Bacteria and viruses are used as vectors. 

Which of the statements given above is/are correct? 

(a) 1 Only 

(b) 2 Only 

(c) Both 1 and 2 

(d) Neither 1 nor 2 

Ans: c

Explanation: 

A recombinant vaccine is a vaccine produced through recombinant DNA technology. This involves inserting the DNA encoding an antigen (such as a bacterial surface protein) that stimulates an immune response into bacterial or mammalian cells, expressing the antigen in these cells and then purifying it from them.

Hence, statement 1 is correct.

Recombinant vaccines are usually produced by benefiting from bacteria, yeast, mammalian, and insect cells. This type of vaccine requires the insertion and transference of the DNA section responsible for encoding the antigen. 

Most of the recombinant vaccines developed in the recent decays are classified as recombinant protein vaccines

In some live recombinant vaccines, an attenuated virus or bacterium is used as the carrier vector. These carriers make the immune system’s response very similar to that of natural infectious microorganisms. The microorganism’s DNA attaches to the vector and stimulates the human immune system.  

Hence, statement 2 is correct.

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