Immune System

6. Location where T cells mature
7. Large protein molecules produced by plasma cells to bind specific antigens
9. Specialized macrophages in the liver
10. Surface molecule used by cells to display antigen fragments for recognition
14. Term for swelling, redness, heat, and pain — classic signs of this immune response
15. Term for the immune system’s ability to distinguish self from non-self
16. Enzyme-containing vesicle that fuses with a phagosome to digest pathogens
17. Process of engulfing and destroying pathogens by immune cells
19. Chemical released by mast cells that causes vasodilation and swelling during inflammation
20. Substance that triggers an immune response when recognized as foreign
21. Innate immune cells that kill infected or cancerous cells without prior sensitization
23. Process of a neutrophil squeezing through a capillary wall during inflammation
25. First antibody produced in a primary immune response

1. These proteins, when activated, can form a membrane attack complex
2. Chemical messengers released by helper T cells to activate other immune cells
3. Antiviral proteins secreted by virus-infected cells that help protect neighboring cells
4. This T cell coordinates immune responses by activating both B and T cells
5. Small molecule that is not immunogenic unless attached to a larger carrier
8. Cells that remain after infection to provide faster response upon re-exposure
11. This type of lymphocyte directly attacks infected or cancerous cells
12. Proteins that form pores in the membranes of target cells leading to cytolysis
13. Proteins that coat pathogens to enhance phagocytosis
18. Type of immunity you are born with that provides the first line of defense
22. This complement process tags pathogens to make them easier to phagocytose
24. Class of antibodies that crosses the placenta to provide passive immunity to the fetus