Histology, B Cell Lymphocyte

Excerpt

B cell or B lymphocyte (bursa-derived cells) is a key player of the adaptive immune response that is responsible for humoral immunity in mammals. B-cell production in humans is a lifelong process that starts in the fetal liver intrauterine and bone marrow after birth. Their development is from hematopoietic stem cells. B-cell development constitutes of all the stages of early differentiation in the absence of antigen interaction until the maturation, antigen interaction, and, ultimately, antibodies synthesis. By this process, B cells acquire two important features of adaptive immunity: (1) discrimination between self and non-self (the ability of B-cell to recognize foreign antigens rather than self-antigens) (2) memory (the ability to recall the previous contact with antigens, therefore, subsequent interaction leads to a more effective and quicker response).

B cells acquire their name from the early experiments on chicken that demonstrate the synthesis of antibodies. Max Cooper founds that antibody production in chicken requires an organ called the bursa of Fabricius in the 1960s. Antibody production was inhibited after the surgical removal of the bursa. The cells that are responsible for antibodies production were called bursa derived or B cells. In contrast to chicken, B-cell development in humans took place predominantly in the bone marrow. Many B-cell differentiation pathways demonstrate characteristic specific surface markers (CD markers) and immunoglobulin (Ig) gene arrangements. Additionally, developmental checkpoints exist along the pathways to determine whether the cell goes into the normal pathway or an alternative pathway resulting in cell death.