Question

what is the difference between Opsonins and cytokines?

Answer 1

Opsonins

Cytokines

An opsonin is any molecule that enhances phagocytosis by marking an antigen for an immune response or marking dead cells for recycling. Opsonins aid the immune system by marking the dead and self dying cells for clearance by macrophages and neutrophils,activate complement proteins and target cells for destruction through the action of natural killer (NK) cells. Opsonins bind to the target cells where the negative charges in the cell membranes makes it difficult for two cells to come together. By binding to these cells they boost the kinetics of phagocytosis by favoring interaction between the opsonin and cell surface receptors on immune cells.

Cytokines are broad and loose category of small proteins which act as immunomodulating agents in autocrine signaling,paracrine signaling and endocrine signaling. Cytokines act through the receptors and modulate the balance between humoral and cell-based immune responses and they regulate the maturation,growth and responsiveness of particular cell populations. Cytokines are important specifically in host responses to infection,immune responses,inflammation,trauma,sepsis,cancer and reproduction.

From the above it is seen that Opsonins are those which help in clearing the dead cells ,thereby aiding the immune system ,whereas Cytokines are those which modulate the immune response or functioning of the immune system.

Though they have different functions, both opsonins and cytokines aid to have a healthy immune system.