title: Coelomocyte locomotion in the sipunculan Themiste petricola induced by exogenous and endogenous chemoattractants: role of a CD44-like antigen--HA interaction.
abstract: Cell migration is a key event in the invertebrate immuno-defense system. Microbial products like lipopolysacharide (LPS) and formyl-methyl-leucyl-phenylalanine (fMLP) promote cell recruitment to sites of infection. In mammals, complement activation by factors such as zymosan induces C5a production, which influences leukocyte migration. The endogenous factor hyaluronic acid (HA), an extracellular matrix component, also promotes cell migration through its receptor CD44. We evaluated whether coelomocytes from the sipunculan worm T. petricola migrated towards LPS, fMLP, or zymosan treated plasma (ZTP) and if HA was involved in coelomocyte migration and adhesion. We also evaluated if antibodies specific for mouse HA receptor CD44 inhibited any of the effects induced by HA. Using microchemotaxis chambers we found that coelomocytes migrated towards exogenously and endogenously derived chemoattractants. We also observed that HA was a potent chemotactic signal and that coelomocytes adhered strongly to plates coated with LMW-HA but not with HMW-HA. In addition we found that these HA mediated effects were blocked by the monoclonal antibody IM7 directed to mouse CD44, suggesting that a CD44-like cross-reactive antigen might play a role in HA mediated coelomocyte locomotion.
authors.affiliation: Department of Immunology, IDEHU-National Research Council (CONICET), School of Pharmacy and Biochemistry, University of Buenos Aires (UBA), Argentina.
authors.forename: Paula V
authors.initials: PV
authors.lastname: Cabrera
authors.forename: Guillermo
authors.initials: G
authors.lastname: Blanco
authors.forename: Glenda
authors.initials: G
authors.lastname: Ernst
authors.forename: Elida
authors.initials: E
authors.lastname: Alvarez
authors.forename: Edwin L
authors.initials: EL
authors.lastname: Cooper
authors.forename: Silvia
authors.initials: S
authors.lastname: Hajos
mesh_terms: D000818:Animals; D002465:Cell Movement; D002630:Chemotactic Factors / Q000494:pharmacology* / Q000502:physiology*; D004347:Drug Interactions; D018960:Hyaluronan Receptors / Q000502:physiology; D006820:Hyaluronic Acid / Q000502:physiology; D009348:Nematoda / Q000166:cytology* / Q000187:drug effects* / Q000502:physiology
chemical_list: D002630:Chemotactic Factors; D018960:Hyaluronan Receptors; D006820:Hyaluronic Acid