Immunology 341 Final Exam Concepts

Which of the following statements is NOT correct? A.) Sites where PRRs can be expressed include the cell surface, within endosomes, in the cytoplasm, and as secreted molecules that circulate the blood B.) DAMPs are released when host cells undergo necrosis C.) TLRs are a type of PRR that is expressed by all cells of the body D.) Signaling adaptors lead to the activation of different cellular responses after recognition of PAMPs by PRRs E.) PAMPs and DAMPs both alert the immune system to the presence of a threat - correct answerC What leads to the greatest amplification of the complement cascade? - correct answercomplement activation via the classical pathway What are the functions of the myeloid cells? - correct answer- mediate phagocytosis - mediate granule release - respond immediately to challenge - transport antigens to lymph nodes What are outcomes of the complement activation? - correct answer- increased neutrophil entry into tissues - increased phagocytosis - proteolytic cleavage - bacterial lysis What does VDJ recombination accomplish? - correct answerincreases the diversity of the variable regions of antigen receptors What plays an important role in promoting the resolution of inflammation? - correct answer- microbial clearance by infiltrating neutrophils - switch in lipid mediator biosynthesis to the production of resolvins - production of inhibitory factors by macrophages at the site of inflammation - ingestion of apoptotic cells by phagocytes Which of these events is NOT associated with the presentation of endogenous antigens? A.) Endosomes fuse with lysosomes to initiate protein breakdown B.) TAP shuttles peptides into the endoplasmic reticulum (ER) C.) An immunoproteasome is used for to generate peptides D.) Tapasin binds to MHC class I molecules to bring them into close proximity with TAP E.) MHC class I molecules are transported from the ER to the cell surface - correct answerA Which types of PAMP is most likely to require internalization into an endosome for recognition? - correct answerbacterial DNA What are the characteristics of dendritic cells (DCs)? - correct answer- detect threats via PRRs - produce factors that activate lymphocytes - become highly motile after antigen uptake - reside throughout the body near epithelial surfaces Describe the difference of recognition of antigens by TCRs but NOT by BCRs. - correct answerTCRs require the participation of another cell in order to recognize antigens What is primarily responsible for antigen recogntion by a BCR? - correct answera close match between an epitope and the antigen-binding site What are the characteristics of chronic inflammation? - correct answer- presence of high grade fever - presence of fibrotic deposits (scarring) in tissues - slow and protracted onset - associated with pathology of many disease You scratch yourself on the back of the hand slightly breaking the skin, and within a few seconds you notice that there is swelling in the area immediately around where you scratched yourself. What is the most likely explanation for this swelling? - correct answerhistamine is being released by mast cells and macrophages in the tissue near the wound site What is the role of cytokines secreted by macrophages during acute inflammation? - correct answerthey activate systemic responses such as fever and production of acute phase proteins by the liver What are the results from PAMPs binding to PRRs on a DC? - correct answer- processing of ingested proteins to product peptide fragments - presentation of peptide antigens at the cell surface of the DC by MHC class II molecules - migration of DCs to lymph nodes - up-regulation of co-stimulatory molecules on the surface of the DC Which of the following statements is NOT correct? A.) Macrophages carry out phagocytosis B.) B lymphocytes mediate granule release C.) Neutrophils carry out phagocytosis D.) Mast cells release granules containing potent mediators of inflammation E.) Natural killer cells are lymphocytes that mediate innate immune functions - correct answerB