“I Effects of Radiation on Living Organisms Project Title: 14, Scope: Radiosensitivity of Immune Responses and Mechanisms of Immune Reactions RX-03-O1-(b) (Cont'd.) resulting from such infections may range from being negligible in some flocks to well over 50% in other flocks. It has also been demonstrated that certain families and lines of chickens are more resistant (or susceptible) to the development of leukemic tumors. That resistance and susceptibility to the avian leukosis in chickens are inherited traits has been demonstrated by Hutt and Cole in selecting over 20 years of sires and dams of families which had a low as well as a high incidence of tumors. However, to date the mechanisms for resistance and susceptibility to leukosis are largely unknown. The proposed studies will utilize genetically inbred leukosis-susceptible and resistant specific pathogen free (SPF) chickens from the University of Massachusetts, Cornell University, and the Federal Regional Poultry Laboratory, East Lansing, Michigan, Two different types of RNA viruses (Type I} - RIF and Type III - T) and one DNA virus (Type II - JM) will be used for inoculation. Gamma and x radiation will be delivered in doses from 10 to 500 rads by whole-body exposure, Avian and mammalian cell cultures will also be irradiated. The antigen-antibody studies will be analyzed by complement fixation, fluorescent-antibody (direct and indirect), immunodiffusion, serum and virus neutralization,and indirect hemoagglutination tests, 15. (Pavlova) Relationship to Other Projects: Related studies at Brookhaven National Laboratory are those of Cronkite, , Chanana, and Joel on Lymphopoiesis and homograft rejection, and of Shellabarger on Radiation-Induced Carcinogenesis. At Argonne National Laboratory, Jaroslow's studies on radiosensitivity of antibody responses, andthe studies of Finkel, Reilly, Greco, Rockus, and Dale on Strontium-90 and angiotensin in mice are related, Studies elsewhere include those of: Loan, Storm, Sloan, and McCune at the University of Missouri, Sevoian at the University of Massachusetts; Jansen, Atomic Energy Board, Pretoria, South Africa; Vos, TNO Radiological Defense Lab., The Netherlands; van Bekkum, Balner, de Vries, van Rood, Radiological Institute, The Netherlands; Micklen, — University of Edinburgh; Betz and Simar, University of Liege, Belgium; Simic, Slivic, Cirkovic, and Petrovic, Boris Kidric Institute of Nuclear Sciences, Beograd, Yougoslavia; Silverman, University of North Carolina; Fitch and Wissle University of Chicago, Meier, Heiniger, Taylor, Chen, Cherry, The Jackson Laboratory; Martin, Mourer, and Benacerraf, Harvard Medical School; and Herzegberg, Stanford University. we 16, nical Progress in FY 1973: Preliminary results with Cottier et al. (University of Bern) concerning cellular kinetics of lymphoid tissues indicate that more time periods during immunization need to be studied, Secondary tetanus antitoxin responses were elicited in normal and irradiated mice (500 rads) and H-3-histidine was injected on day five after booster injections of fluid toxoid and complexes (See Continuation Sheet) [119271 RX-178