Question

A boy of 10years had chicken- pox. He is not expected to have the same disease for the rest of his life. Mention how is it possible.

Answer 1

The antibodies are produced by the human body against the antigen. The antibodies respond against the antigen depending on the intensity of the immune response generated.

Step by step answer: Antigen or virus, bacterial or any pathogenic particles enter the body by skin, wound, mouth, and other ways. The antigen is first detected by the innate immune system and acts immediately against the antigen. This allows neutrophils migration to the site of infection, which further allows migration of monocytes and dendritic cells. Monocytes mature to form macrophages and act on the antigen to kill them. The innate immune system also activates the complement pathway and forms many immune reactions to kill the antigen.
This allows further activation of T-cells and B-cells. T-cells have T cell receptors and by antigen presentation, they activate B-cells. B-cell activation and differentiation allow the formation of antibodies against the antigen or a part of antigen. These antibodies are released in the bloodstream and act on the antigen. B-cells also form memory B-cells. These cells have the memory antibodies formed against the chickenpox virus. So, when the Varicella Zoster Virus (chickenpox virus) is exposed again, the memory immune cells kill the virus there and there as they have antibodies against the virus particles already formed and thus don’t have to go through the whole immune response again. Immunogenicity also depends on the structure and composition of the pathogen, its size, and also on the physiology of the person.

Note: Varicella-Zoster Virus (chickenpox virus) is very sensitive to the immune cells and thus form a very strong immune response. These allow the formation of a high number of antibodies and memory B-cells.