Which of these is false regarding cytokines:: (A) Mediators of inflammation, (B) Does not mediate specific reactions, (C) Produced by macrophages, (D) Are soluble proteins
Answer is B. Cytokines mediate their effects by binding to specific high-affinity receptors on their target cells. Specific cytokines mediate specific reactions.

Other important characteristics of cytokines

Cytokines are soluble proteins produced by a wide variety of hematopoietic and non-hematopoietic cells.
They are short acting.

They are required for

Regulation of growth
Activation of the immune system
Mediation of inflammatory response