CELLULAR RECOGNITION OF FOREIGNNESS IN 2 INSECT SPECIES, THE AMERICAN COCKROACH AND THE DESERT LOCUST

  • 1 January 1979
    • journal article
    • research article
    • Vol. 36  (4) , 909-914
Abstract
Encapsulation of tissue implants by hemocytes was used as the assay for immune recognition in the insects studied. In hemocytes attach to and encapsulate an object implanted within the hemocoel, it may be assumed the implant is recognized as not-self, lack of encapsulation of tissue implants may be assumed to indicate lack of recognition. The American cockroach, Periplaneta americana, and the desert locust, Schistocerca gregaria, were used both as donors of tissue, and as recipients of tissue implants from various insect species. Allografts were not recognized as foreign and were not encapsulated by hemocytes of either S. gregaria or P. americana, a phenomenon which was frequently reported for other insect species. Hemocytes of S. gregaria recognized and encapsulated a smaller range of xenografts compared with hemocytes of P. americana, and it appears that the acuity of immune recognition by hemocytes differs between S. gregaria and the other species tested. Reasons for the different recognition responses of P. americana and S. gregaria are suggested and discussed with particular reference to the results for Nauphoeta cinerea tissue in P. americana, and Gryllus domesticus tissue in S. gregaria, where at least half the number of implants are totally but weakly encapsulated, and it is suggested that hemocytes do not react to difference unless it surpasses a certain threshold.