INDUCTION OF ACTH-LIKE AND TNF-ALPHA-LIKE MOLECULES IN THE HEMOCYTES OF CALLIPHORA-VOMITORIA (INSECTA, DIPTERA)

Three basic cell types are described in the hemolymph of newly eclosed adult Calliphora vomitoria: prohemocytes, plasmatocytes, and granular cells. In addition, anucleate cellular fragments with some inclusions are observed, Cell division is found only in the prohemocytes, Plasma tocytes and granular cells are capable of in vitro bacterial phagocyto sis and take part in capsule formation. Adrenocorticotropin hormone (A CTH)-like molecules are found in both cell types. The staining of the plasmatocytes is related to the functional activation of the cells. In deed, positive staining is only observed during capsule formation, sug gesting an induction of ACTH expression, The behaviour of tumor necros is factor (TNF)-alpha-like molecules is similar, In conclusion, these data provide further support for the close, evolutionary relationship between the immune and the neuroendocrine systems.