Stimulation of the nucleic acid sensing TLRs that reside in endosomal membranes induces the production of a different cytokine response than is produced by stimulation of the plasma membrane TLRs. In part, this distinction is based on the different adapter proteins used by the nucleic acid sensing TLRs, leading to the activation of IRF factors. The cytokine response following stimulation of nucleic acid-sensing TLRs is characterized by production of:

Correct Answer: A

Rationale: Endosomal TLRs (e.g., TLR-3/7/9) produce type I interferon via IRF; TNF-α , peptides , or chemokines are plasma TLR-related.

Correct Answer: B

Rationale: Acquired immunity develops from prior exposure, such as through vaccination, which stimulates the immune system to remember pathogens.

Correct Answer: C

Rationale: Adaptive immunity relies on a vast lymphocyte repertoire, each specific to a unique antigen, not changing specificity or stem cell-driven receptors.

Correct Answer: C

Rationale: Autoimmune responses harm self-tissues, unlike inflammatory, humoral, or complement responses, which are typically beneficial.

Correct Answer: D

Rationale: Interleukins are cytokines acting between leukocytes, a broad term encompassing lymphokines (lymphocyte-derived) and others.