CD14

The immune system is composed of a portion of T cells that express an invariant T cell receptor (TCR) alpha chain known as V alpha 24 J alpha 18. These highly conserved populations are referred to as iNKT populations and have the ability to rapidly produce cytokines following activation, making them hot targets for therapeutic research initiatives.

Toll like receptors (TLRs) are highly conserved proteins that are first known for their role in pathogen recognition and immune response activation.  In order to elicit the necessary immune response in reaction to a foreign pathogen, TLRs trigger cytokine production depending on the behavior patterns of the pathogen itself.  Specifically, TLR4 acts through bacterial lipopolysaccharide (LPS), which composes the outer wall of Gram-negative bacteria.  Bacterial LPS is also a potent activator of the immune system.

CD14 is a well-characterized cell-activating receptor for lipopolysaccharide-binding protein (LBP) and peptidoglycan. It is an important modulator for lipopolysaccharide (LPS)-dependent signaling and is a component of the multi-protein complex containing also containing MD2 and toll-like receptor 4 (TLR4). CD14 is an important component of the innate immune response preferentially expressed on mature cells of monocyte lineage. The CD14 protein contains eleven leucine-rich repeats (LRRs).

Think B lymphocytes just produce antibodies? Think again! Although, of course, B cells are vital for the humoral immune response, many studies in recent years have begun to uncover antibody-independent actions of B cells: regulating T cells and thus also playing a part in cellular immunity. For example, B cell depletion therapy, a new treatment for autoimmune disorders, has been found to influence T cells in addition to antibody titers.