Only lymphocytes possessing receptors that can bind with the antigens on an invading pathogen are involved in the immune response against it.
B cell receptor refers to an immunoglobulin molecule which serves as a type of trans membrane protein on the surface of B cells while an antibody refers to a blood protein that the B cells produce in response to and counteracting a specific antigen.
Thus, this is the main difference between B cell receptor and antibody.
Its function is as a receptor that recognizes and binds antigen by the V regions exposed on the surface of the cell, thus transmitting a signal that causes B-cell activation leading to clonal expansion and specific antibody production.
Learn more about receptors and antigens here:
