Abbreviations

Innate lymphoid cells Innate immune system Induce resistance to pathogens Regulation of autoimmune inflammation Metabolic homeostasis Tissue remodeling Play important roles in barrier tissue such as skin, lungs, and intestine

antimicrobial peptides Part of innate immune response Broad spectrum antibiotics which have potential as therapeutic agents Kill gram negative and positive bacteria, enveloped viruses, fungi, cancerous cells Function as immunomodulators

Antigen presenting cells Heterogenous group of immune cells that mediate the cellular immune response by processing and presenting antigens for recognition by certain lymphocytes such as T cells Classical APCs include dendritic cells, macrophages, B cells

Natural killer cells Type of lymphocyte Part of innate immune system Play major role in host rejection of tumors and virally infected cells They are cytotoxic; have granules in their cytoplasm which have perforin and proteases Are activated in response to interferons or macrophage derived cytokines

Mucosa associated lymphoid tissue Diffuse system of small concentrations of lymphoid tissue found in GI tract, thyroid, breast, lung, mouth, eye, skin Populated by T cells and B cells and plasma cells and macrophages Regulates mucosal immunity

Dendritic cells Antigen presenting cells Process antigen material and present it on the cell surface to the T cells Act as messengers between the innate and adaptive immune systems

Immunoglobulin Antibodies made by plasma cells Specifically recognize and bing to certain antigens, aiding in their destruction

T cell receptors A molecule found in the surface of T cells Recognize fragments of antigen as peptides bound to major histocompatibility complex (MHC) molecules Adaptive immune response

B cell receptors Receptor protein on surface of B cells Has membrane bound antibody that has an antigen binding site When it encounters antigen, the B cell proliferates and differentiates to generate a population of antigen secreting plasma B cells and memory B cells Functions in signal transduction Mediates internalization for subsequent processing of the antigen and presentation of peptides to helper T cells

Pathogen associated molecular pattern Molecules associated with groups of pathogens Recognized by cells of the innate immune system small molecular motifs conserved within a class of microbes

Pattern recognition receptors Play a key role in innate immune response by recognizing conserved pathogen associated molecular patterns (PAMPs), which are unique to each pathogen

Major histocompatibility complex Set of cell surface proteins essential for the adaptive immune system to recognize foreign molecules Binds antigens derived from pathogens and display them on the cell surface for recognition by T cells Mediate interactions of leukocytes with other cells

Fragments of antigen binding Region on an antibody that binds to antigens Composed of one constant and one variable domain of each of the heavy and the light chain

Crystallizable fragment The tail region of an antibody that interacts with cell surface receptors called Fc receptors and some proteins of the complement system Allows antibodies to activate the immune system

Toll like receptor Class of proteins that play a key role in the innate immune system Receptors usually expressed on macrophages and dendritic cells Recognize structurally conserved molecules derived from microbes (PAMPs) or danger associated molecular patterns (DAMPs)

Reactive oxygen species Chemically reactive species containing oxygen Component of the killing response of immune cells to microbial invasion Produced in part by phagocytic cells