Role of B-cells in growth hormone-immune interactions.

Cells demonstrating cell surface markers for B-cells tend to be normal in growth hormone (GH)-deficient children. Treatment with pituitary-derived or recombinant human GH, however, produces a significant, albeit transient, decrease in the number of these cells both in vitro and in vivo. Receptors for GH have been detected on numerous cells of the immune system, notably B-cells and monocytes. Recent studies have shown that cells of the immune system are able to produce peptide hormones, such as GH, and studies in the rat (which have yet to be confirmed in humans) suggest that the B-cell is the cell type most involved in this production. These findings suggest that the B-cell has a significant role in the bi-directional communication network between the endocrine and immune systems.