a pe ae frat VM Ps 9 oP — Jamary 21, 1959 Vi TO: Dr. Nethan Smith, “edtatrics FROM: B41) Stone, Genstics sUcJECT: Possible investigations with individuals who have hed neonstal exchange transfusions. 1. Sxamine blood types for mosaicism (chimerism): Since whole blood is generally use exchange transfusions, 8 possible that some celle are tranaplanted to the host which can maintain themse’ves as part of the hemapoietic system. A careful study of the blood type of the host wight reveal chimerien of the cells. It would be advantageous to heve the blood type of the donor ss well as a complete battery of human blood tyning reagents. Starch electrophoresis could be done to lock for chimeriam of serum sudstances. 2. Try skin homotransvlants: If chimeriem exists, skin transplants shoul? take. Algo, if tolerance were engendered and maintained, skin grafte should take. It would require skin from the donor. 3 Hegponse to jmmunigation with blood: If the host were made tolerant to tyre specific antigens of the blood, he may fail to respond following immnisa-~ tion with blood from the donor of en individual with similar blood tyve. ie ms OF meranologies] o wtence: If there were some Teencralized™ tolerance ona result of the trenafusion, the host may be less competent immmologically then his contemporaries. A study of his responses to immnizations, vaccinations, etc. might reveal an effect. 5. Exemination of serum for neturally oceurring antibodies: “Sinee blood com- vetible for the 25O groups is likely to be used, it is doubtfnl thet tolerance would be engendered for any of these antizens (also true for #3 above). However, there is a possibility thet the neturally oscurring anti- bodies were inhibited. Controls for these observations might be sibs of the hosts. In my opinion, all of thear observations could be made here. We conid attempt at least a preliminary exemination of the blood. The transn’ants and (mmwmize- tions would, of course, require the services of a person from the Medios’ ‘School. mb | ‘HCO BDIVOLF