mes aaeye tree 168 POTTINER RADTATIONS ENDL ACTA AN MFASIMER BY -SPINOLIMIICAL CHANGES THA MANAUALLENE POPULATION RATED TH RADLOACTEIVE FALIAHIE AUREMT A, GOMANED Medhtvel Uepaitewat, Aroukhaven Naliened Laboratory, Upton, Wo. LUST? Imminnlogical ceeprerence was evaluated lo teat radfat lon- induced aning in @ Marshall Teland population of 45 penpis who had received 17> rade of ganas radiation 15 years before as a result of exposure te redinactive fallout. The results were compared in_ 150 unezposed Harahalicee Living on the name Leland, Electenphoretic studtes and unexposed populetiona. in the exposed however, showed an increase in albumen and aignif icant depreaaton of gamma and alpha globulins in the exposed group. Imeunediffusion studies showed the [gd and to a leaser extent the [sG moieties and also the L light chains were below unexposed levels. Thean Cindings were interpreted to Undicate reduction in temenological teserves, The tenlency wan (or the depression of these moteticn Co be relatively qreater in the alder groupe. Tha percent transiarmetion of cultured peripheral blood tymphocyt--« fallowing phytohemag luttia atimulation wae found to show depression with age in both exposed The rasuits were not significantly different from those in the unexposed gtoup, Peripheral blood levele of thrombocytes and houteophils were depressed in the cider exposed Harshatlese compared with unexposad groups of the same age. In spite of the above findiags loss of imeunological capacity in che exposed population hae not been apparent based on comparison of Incidence and severity of dicoases ta the exposed coupared with the wexpesed grouse.