Question

explain how CD8, CD4 and B cells work together either in the lymphoid tissue OR at the site of infection.

Answer 1

The human immune system consists of an innate immune system that is present at birth and an acquired immune system that is developed through ones life.The primary functio of the immune system is to identify and eliminate poos ible infection and pathogens and foreign antigens.Anfd there is also development of immunologic memory so that subsequent infection by the same pathogen will elicit a secondary immune response to evade the pathogen.The lymphocyte population is mainly made up of Thymus derived lymphocytes and blood derived lymphocytes ie B and T cell Lymphocytes.

B lymphocytes mainly mediate the humoral immunity which is closely involved with innate immunity.The CD4+T cells and CD 8+T cells make up the major part of T lymphocytes.The CD4+cells after being activated into effector cells plays an important role in immune system activationby secreting specific cytokines.The CD4+ cells plays a major role in activation of the innate immune system including the B cells.The CD4 communicates with the antigen presenting cells.and inurn leads to the activation of the B Lymphocytes leading to release of pathogen specific antibodies and causes lysis of the cell membrane and the antigen presenting cells like dendrites activate the CD8 cells that is also known as cytotoxic T lymphocyte which also causes destruction of the the antigen or pathogen thus the CD4 and CD 8 cells together with B lymphocytes form aa cascade of immune responses that help in evading the antigen