Comprehensive immunogenetics / W.H. Hildemann, E.A. Clark, R.L. Raison.

  • Hildemann, W. H., 1927-
Date:
[1981], ©1981
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Comprehensive immunogenetics / W.H. Hildemann, E.A. Clark, R.L. Raison. Source: Wellcome Collection.

    337/392 (page 317)
    Immunorecognition and ImmuriiKompctcnce in Invertebrates 317 same organism show parallel development in actively immunized wax moth larvae of the order Lepidoptera. The promptness and short duration of these immune responses are noteworthy, since selective reactivity appears within hours and then disappears after several days. Indeed, this timing alone could be viewed as evidence against vertebrate-type adaptive immunity in arthro¬ pods. However, other examples tend to counteract the view that arthropods lack immunologic potential altogether. Spiny lobsters immunized with a Gram-negative bacterium isolated from their own normal intestinal flora soon produce a typical nondialyzable bactericidin. Cross-reactions are found with other Gram-negative organisms, but not with Gram-positive bacteria. Higher bactericidin titers are elicited by secondary injections of the same antigen, whereas various unrelated substances do not provoke bactericidin responses. In American cockroaches, injection of Tetrahymena yielded a specifically im¬ mune hemolymph after three days, capable of immobilizing suspensions of these ciliates. This hemolymph also passively protected naive cockroaches from otherwise lethal doses of Tetrahymena. Immobilizing activity resided in a particular protein band isolated by disc-gel electrophoresis. Regular acceptance of imaginäl disc and ovarian allografts in larval Droso- phila has been known since the classic studies of Beadle and Ephrussi in 1935. Among cockroaches, skin allografted between nymphs or from adults to nymphs retained its integrity through successive molts. Even supernumerary legs allografted between larval house crickets have persisted through molting to the adult stage. Given the immature larval state of the recipients in these experiments, acquired tolerance could be implicated. However, orthotopic al¬ lografts of legs between adult crayfish have regularly been found to remain viable for many weeks at 25° C, even after molting. Absence of allograft en¬ capsulation in several species of insects where xenografts do elicit this response to foreignness could be interpreted as a lack of subtle immunorecognition by participating leukocytes or hemocytes. Yet other studies reveal a reproducible distinction between allograft and isograft reactions leading to the opposite conclusion, at least with Hymenoptera. Definitive transplantation studies in adult arthropods, including tests for selective memory, are still lacking. If weak histoincompatibilities are the rule in arthropods, their detection could require a species with a long life span—months rather than just weeks. At this juncture, the very existence of discriminating adaptive immunity in arthropods is in doubt. Orthotopic tissue grafting has proved quite difficult in many mollusks for technical reasons. Certain species of snails can effectively distinguish among isografts, allografts, and xenografts, but quantitative studies including tests of memory by repeat grafting have yet to be reported. A preliminary study of tissue transplantation in scallops suggested better survival of autografts than of similar heterotopic allografts, but no conclusions were drawn because of technical shortcomings. Some cellular immunocompetence in oysters is sug¬ gested by studies revealing immune elimination of bacteriophage. As in other invenebrates, the capacity of mollusks to synthesize immunoglobulin anti-