| | \ 40 | Antibody response. Three years after exposure a _ duced bone marrow reserve and therefore reduced immunological reserve. The apparentrecentrecov- ery of hemopoiesis in the exposed people to control levels may indicate an improvement in their immunological status. Table 18 shows that reductions in lymphocytes andplatelets and an increase in sedimentation rates were correlated with increasing age in the Marshallese. Immunoprotens, Immunoelectrophoretic analysis of serum proteins in 1962 showed neither a paraproteinemia nora typical picture of antibody de- The antibody titers appeared somewhatlowerin the exposed people. !0 The older people had higher levels of gamma globulins but slightly decreased albumin levels (1969).13.59.60 Immunodiffusion studies showed that the rise in gamma globulin levels was paraileled by an increase in immunoglobulin.t The increase in IgG moiety was the most pronounced, and it showedsignificant correlation with age (r =0.78). The increase in K light chains was also significantly correlated with age. The immunoglobulin levels were more depressed in the exposed group, particularly those-of IgG, IgA, and L light chains (Table 18). However, by 1974 the gammaglobulin levels in the exposed people were nearly the sameas in the unexposed (Table 19). Lymphocytefunction. Tests on the phytohemagglutinin (PHA) stimulation of lymphocytes cul*Dr. R.D. Stoner at BNL did these analyses. **Drs. R. Butler and A. Hassig at the Swiss Red Cross Labora- tory did these analyses. *These studies were done by Drs. J.L. Fahey and R. Woods of the National Cancer Immunoglobulin Center. T , i 7 0 | ~ r=0.99"* ¥=0.51 +0.38 x+0.01 x? | 601 = 50t- — . - | 4 1 i 30 -— “Coefficient for age | correlation of each cnterion used to weight scores before surmming | 20 = 7 | 10 ~ ol | **Correlation with age | ! +0 significant at 1% level 50 | 60 70 4 ! 80 | | Age ficiency syndrome, but a high frequency of some of the immunoglobulins was noted.!0** Complement fixation studies showed the Marshallese to have antibodies to most viruses except Asian influenza (an epidemicofthis disease later occurred in 1972). T error means 70Percent aging recovery of leukocytes was believed to reflect re- ] e@ Unexposed ' mary and secondarytetanus toxoid inoculations, with a mouse used for toxin-antitoxin assay of I = Combined with standard 80) number of exposed and unexposed Rongelap people weretested for antibody responseto pri- serum.5* The difference between the exposed and unexposed groups was notsignificant. Blood cell changes. The persistent lag in complete Tr Combined weighted data* > Exposed s duced immunological surveillance. Our interest in immunological capacitv is related also to the consideration that impairmentof immunity is thought to be associated with the aging process. Figure 23. Biological age scores. !* tured from peripheral blood showed a definite decrease of responsiveness with increasing age of the individual (Table 18 and Figure 24) but no def- inite difference between exposed and unexposed groups.59.69 In a more recent study, acetylation of nuclei of PHA-treated lymphocytes was measured at various times as a function of lymphocyte transformation and of aging.) Decreased acetylation of nuclei is associated with increasing age and1s roughly parallel to the decrease in lymphocyte transformation. Total acetate incorporation in the nuclei during the first hour of culture was correlated with acetylation of histones, but by 20 hr acetylation of other nuclear materials had also occurred. Chromosome counts. In 1969 chromosome counts were made on PHA-stimulated lymphocytes cultured from peripheral blood from 78 unexposed and 27 exposed Rongelap people.*? Both hypodiploid and polyploid levels were found to be related to the subject’s age. Females >>50 and exposed males >50 had ~1.5 times as many hypodiploids as did the younger subjects; polyploid levels were sharply reduced in all subjects >50. Hv-