Desensitization immunotherapy administers allergen in controlled amounts and stimulates T regulatory cell populations. Which of the following is not a correct statement about this therapy?ANSWERRegulatory T cells stimulate T helper 1 cells.The level of IgG is increased as a result of the desensitization immunotherapy.As a result of the controlled injection of the allergen, the number of IgE molecules is increased.Regulatory T cells discourage T helper 2 cell activity.

In type I hypersensitivities, allergen exposure triggers the immune system to produce __________. This is called the __________.ANSWERIgG; postsensitization exposureIgE; degranulationplasma cells; postsensitizing exposureIgE; sensitizing exposure

An activated T helper cell becomes either an effector T helper cell or a memory T helper cell. What is the function of the effector T helper cell?ANSWER“Remember” the specific antigen and respond next time it is encounteredDestroy infected cells, cancer cells, and transplanted tissueRelease factors that help T cytotoxic cell and B cell activationRelease antibodies

An activated T helper cell becomes either an effector T helper cell or a memory T helper cell. What is the function of the effector T helper cell?ANSWERRelease factors that help T cytotoxic cell and B cell activationRelease antibodiesDestroy infected cells, cancer cells, and transplanted tissue“Remember” the specific antigen and respond next time it is encountered

Which of the following is the primary activation signal to fully activate T helper cells?ANSWERThe TCR/MHC/antigen interaction is assisted by CD8 on the surface of T helper cells.The B7 protein on the APC cell surface interacts with CD28 on the surface of T helper cells.The TCR of the T helper cell interacts with the MHC I–antigen complex.The T-cell receptor (TCR) of the T helper cell interacts with the MHC II–antigen complex.

Match the immune tolerance mechanisms in Group I with their respectiveoutcomes in Group II.Group I Group IIP. Anergy 1. Elimination of activated T-cellsafter antigen clearanceQ. Activation-induced cell death 2. Inhibition of auto-reactive T-cells atperipheryR. Receptor editing 3. Unresponsiveness to antigens due tolack of co-stimulatory moleculesS. Regulatory T-cells 4. Elimination of auto-reactive B-cells(A) P-3, Q-1, R-4, S-2(B) P-4, Q-3, R-1, S-2(C) P-3, Q-4, R-2, S-1(D) P-3, Q-2, R-4, S-1