Interferons and interleukins are two good examples of it.

Interferons can be produced by infected cells or immune cells in response to infections or tumors. One of their functions is to slow down replication of RNA to slow down the replication of the pathogen or the cancer cells. And interferons also targets other cells to lower their vulnerability against the infection.

Interleukins (or cytokines) are mostly regulators of the immune response. They activate and target immune cells against pathogens or antigens, they control their replication, the production of antibodies and the differentiation of the many immune cells (like memory lymphocytes, useful against a second infection). Cytokines are produced by immune cells but also many other cells in your body and another of their functions is to regulate the immune response to avoid self-immune reactions. A cytokine storm is an acute disproportionate cytokinic response to an infection. That's what caused so many deaths at the begining of the COVID pandemy.