Host Defenses II – Adaptive Defenses & Immunization
Across
- 2. CD8+ T cell that directly kills infected or cancerous cells after recognizing antigen on MHC I.
- 5. B Cell Receptor; a Y-shaped transmembrane protein on B cells that binds directly to intact antigens.
- 8. CD4+ T cell that acts as the "conductor" of the immune system; recognizes antigen on MHC II and activates other immune cells.
- 10. The specific, small portion of an antigen that is recognized and bound by an antibody or T cell receptor.
- 12. Lymphocyte that matures in the bone marrow and is responsible for the humoral immune response; produces antibodies.
- 14. Transfer of pre-formed antibodies to a patient; provides immediate but temporary protection with no memory cell formation.
- 18. Long-lived B or T cell that remains after an infection; enables a faster, stronger response upon re-exposure to the same pathogen.
- 20. Major Histocompatibility Complex; host cell surface proteins that display antigen fragments for T cell recognition.
- 21. Historical method of immunization using dried smallpox scabs or pustule material; practiced before modern vaccination.
- 22. Immunity Vertebrate-only immune response characterized by high specificity and immunological memory; slower to develop than innate immunity.
- 24. Response Arm of adaptive immunity mediated by B cells and antibodies; defends against pathogens in body fluids.
Down
- 1. T cell that modulates the immune response to prevent overactivity and limit chronic inflammation; acts as a "brake" system.
- 3. T Cell Receptor; a protein on T cells that recognizes antigen fragments only when they are presented on MHC molecules.
- 4. Artificial active immunization; introduction of antigen (or weakened/killed pathogen) to stimulate a primary response and induce memory cells.
- 6. Response Arm of adaptive immunity mediated by T cells; defends against pathogens inside cells, such as viruses.
- 7. Any substance (often a pathogen protein or polysaccharide) that can elicit a response from a B cell or T cell.
- 9. A type of white blood cell (20-40% of leukocytes) that is the key player in adaptive immunity; includes B cells and T cells.
- 11. Differentiated B cell that functions as an antibody factory; actively secretes large quantities of antibodies.
- 13. Soluble form of the B cell receptor; also called immunoglobulin (Ig); binds to antigens to mark them for destruction.
- 15. Presentation The process by which a cell displays antigen fragments on its surface using MHC molecules for recognition by T cells.
- 16. Class of MHC found on all nucleated cells; presents endogenous antigens (from inside the cell) to cytotoxic T cells.
- 17. Immunity Fast-acting, non-specific immune response found in all animals; lacks memory and uses a limited set of receptors.
- 19. Class of MHC found on antigen-presenting cells (APCs) such as macrophages, dendritic cells, and B cells; presents exogenous antigens to helper T cells.
- 23. Lymphocyte that matures in the thymus and is responsible for cell-mediated immunity; includes helper, cytotoxic, and regulatory types.