Question

Explain how the immune system detects a virus that manage to escape immunity. What natural strategies do we have in our favor, if APCs (antigen presenting cells - ie. macrophages, dendritic cells) fail in their roles?

Answer 1

Virus follow many methods to escape from immune system detection. Virus will produce protein, it react with host sensor proteins and this will prevent the detection of viral genome. When a virus enter the human body it starts to replicate in the host cell and starts infecting the cell. T cell is a part of immune system, which continuously checks for infection. When T cells find infected cell, it will destroy the cell along with the virus. T cell receptors are proteins, present in cytotoxic T cell, which helps to identify the infected cell. When macrophages and dendritic cells fail to perform their role, major histocompatibility complex play an important role in destruction of virus, it helps in to prevent the infection of virus.