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B cells and T cells are two types of lymphocytes (white blood cells) that play an essential role in the immune response. B cells are responsible for producing antibodies, which can neutralize or destroy pathogens, while T cells are involved in cellular immunity, attacking cells that are infected by pathogens.

B cells have membrane-bound antibodies on their surface known as B cell receptors (BCRs). These BCRs directly recognize and bind to antigens. B cells recognize and bind to soluble and native antigens, such as proteins, polysaccharides, and lipids. Once a B cell detects an antigen that matches its BCR, it begins to produce antibodies specific to that antigen, which can neutralize or destroy the pathogen.

T cells, on the other hand, do not directly bind to antigens like B cells do. Instead, T cells recognize and respond to small, processed antigen peptides presented by specialized major histocompatibility complex (MHC) molecules on the surface of antigen-presenting cells (APCs). There are two types of T cells, each recognizing a specific type of MHC molecule: CD8+ T cells, which recognize MHC class I molecules, and CD4+ T cells, which recognize MHC class II molecules.

The key differences between B and T cells concerning antigen recognition are as follows: a. B cells directly recognize and bind to soluble and native antigens, while T cells recognize small, processed antigen peptides presented by MHC molecules. b. B cell receptors (BCRs) are responsible for antigen recognition in B cells, while T cell receptors (TCRs) recognize antigens bound to MHC molecules in T cells. c. B cells are involved in the humoral immune response, producing antibodies that can neutralize or destroy pathogens. In contrast, T cells contribute to cellular immunity, attacking cells that are infected by pathogens. In summary, B and T cells differ significantly in how they recognize and bind to antigens, with B cells directly binding to soluble and native antigens and T cells recognizing antigen peptides presented by MHC molecules. These differences are essential for the distinct roles that B and T cells play in the immune response.