title: Immunological and biological identification of tumour necrosis-like factor in sponges: endotoxin that mediates necrosis formation in xenografts.
abstract: Xenografts of the sponge Geodia cydonium in its closely related species G. rovinjensis resulted in a rapid rejection of the graft within a period of 5 days. We identified an immunoreactive tumour necrosis factor (TNF)-like activity in the xenograft (Mr of 30,000) two days after grafting. In-vivo injection of 5 micrograms human recombinant TNF-alpha induced cytotoxicity in sponge cells in the same pattern and time course as during natural xenograft rejection. Anti-TNF-alpha polyclonals were found to react with xenograft extracts, by Western blot analysis, as from day 2 after grafting. Using ELISA we detected the TNF-like activity from day 2 after grafting with peak levels at days 4 and 5, where the amount was 0.72 ng/micrograms tissue DNA. By day 1, gp27 (inhibitory aggregation factor) is already formed in the xenograft. In-vitro experiments on isolated G. cydonium cells showed that addition of purified gp27 induced the production of the TNF-like activity (up to 13.5 ng/ml). Evidence is presented that gp27 is a product of the gp180 lectin receptor. We conclude that gp27 induces TNF-like factor production, resulting in destruction and dissolution of the xenograft after 5 days.
authors.affiliation: Institut für Physiologische Chemie, Universität, Mainz, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Pfeifer
authors.forename: H C
authors.initials: HC
authors.lastname: Schröder
authors.forename: B
authors.initials: B
authors.lastname: Rinkevich
authors.forename: G
authors.initials: G
authors.lastname: Uhlenbruck
authors.forename: F G
authors.initials: FG
authors.lastname: Hanisch
authors.forename: B
authors.initials: B
authors.lastname: Kurelec
authors.forename: P
authors.initials: P
authors.lastname: Scholz
authors.forename: W E
authors.initials: WE
authors.lastname: Müller
mesh_terms: D000818:Animals; D016923:Cell Death / Q000502:physiology; D004731:Endotoxins / Q000494:pharmacology*; D004797:Enzyme-Linked Immunosorbent Assay; D005109:Extracellular Matrix / Q000502:physiology; D006023:Glycoproteins / Q000502:physiology*; D007267:Injections; D007369:Interferon Inducers / Q000378:metabolism; D008970:Molecular Weight; D009336:Necrosis; D011161:Porifera / Q000737:chemistry*; D014183:Transplantation, Heterologous / Q000473:pathology*; D014409:Tumor Necrosis Factor-alpha / Q000008:administration & dosage / Q000032:analysis*
chemical_list: D004731:Endotoxins; D006023:Glycoproteins; D007369:Interferon Inducers; D014409:Tumor Necrosis Factor-alpha