3. ___________ cells have the specialized function of capturing microbial antigens and displaying them to lymphocytes to initiate adaptive immune responses. 

4. When an individual exposed to the antigens of a microbe mounts a response to eradicate the infection and develops resistance to later infection by that microbe, this is known as ____________ immunity. 

6. ____________ granules serve as reservoirs for lysozyme and lactoferrin 

10. These lymphocytes mature in the thymus and are characterized by their CD2 and CD3 markers. 

12. ____________ immunity is the aspect of immunity that is mediated by macromolecules found in extracellular fluids such as secreted antibodies, complement proteins, and certain antimicrobial peptides 

15. Any molecule that is specifically recognize by lymphocytes or antibodies. 

20. These precursors to macrophage-lineage and dendritic cells have a horseshoe-shaped nucleus and produce lysosome and granules. 

21. Granulocytic cells which release histamine during an allergic response 

22. _____________ granules are reservoirs for such enzymes as myeloperoxidase, ß-glucuronidase, elastase, and cathepsin G. 

23. The lymph nodes and spleen are components of the ____________ lymphoid organs. 

24. Helper T-cells express _____, undergo activation by APCs through class II MHC antigen presentation, and produce cytokines. 

28. This is the region of the lymph node known as the “T-cell zone” 

31. __________ immunity is the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to antigen 

33. These cells are characterized by their bi-lobed nucleus, heavily granulated cytoplasm, and involvement in allergic responses and defense against parasites. 

34. Granulocytes with short life span, multi-lobed nucleus, and granules, which phagocytose and kill bacteria directly. 

35. When a naïve individual receives antibodies or cells (e.g. lymphocytes) from another individual already immune to an infection, or protective antibodies that have been synthesized using modern bioengineering techniques, this is called ____________ immunity. 

36. Common progenitor cell; gives rise to all blood cells. 

Down 

1. These lymphocytes mature in the bone marrow, are activated by antigens and T-cell factors, and are characterized by their production of antibodies and presentation of MHC class II antigens.

 2. This category of immunity provides immediate protection. 

5. The thymus and bone marrow are considered ____________ lymphoid organs. 

7. This is the region of the lymph node known as the “B-cell zone” 

8. The most important physiological function of the _____ system is to prevent or eradicate infections. 

9. Small proteins (~8kDa) that attract specific cells to important immunological sites, and sites of inflammation. 

11. These cells all play roles in innate immune responses 

13. These cells are mediators of adaptive immunity. 

14. Cell that protects the body by ingesting harmful foreign particles, bacteria, and dead or dying cells. 

16. Known as the most potent of the APC’s, these cells initiate, and determine the nature of, the T-cell response 

17. Large, granular lymphocytes which kill antibody-decorated cells, virusinfected cell, and tumor cells. 

18. The lymph node site of B-cell proliferation and plasma and memory cell development. 

19. These cells produce antibodies, have reached terminal differentiation, and are characterized by their small nucleus and large cytoplasm, in contrast to the other lymphocytes.

 25. This category of circulating adaptive immune system mediators includes Bcells and T-cells. 

26. Hormone-like proteins that act on cells to activate and regulate the innate and adaptive immune responses. 

27. Large granular cells possessing Fc and C3b receptors, these phagocytic cells initiate inflammatory and acute-phase responses (M1). As well as remove debris, maintain normal tissue function, and facilitate repair (M2) 

29. Killer T-cells express ___________, recognize antigens presented by class I MHC antigens 30. This category of immunity develops slowly and provides specialized defense 32. A large organ that acts like a lymphnode and filters antigens, encapsulated bacteria, and viruses from blood, and removes aged RBC’s and platelets.