W. H. MANWARING 991 



d) Cafe.— Cats may be sensitized at times sufficiently to give lethal anaphylaxis, 

 by the doses and methods used in rabbit anaphylaxis.' 



e) Rats. — Parker and Parker' have recently sensitized 100 200-gm. white rats 

 by single intraperitoneal injections with i-cc. sheep serum, also by three intraperi- 

 toneal injections of 0.5-cc. sheep serum, given at three-day intervals. Maximum 

 sensitization was observed between seven to eighteen days after the final sensitizing 

 doses. Small rats are apparently incapable of sensitization. 



/) Mice. — White mice may be sensitized by repeated intraperitoneal injections 

 with 0.3-0. 5-cc. horse serum.3 The height of the sensitization is reached in about 

 twenty-one days. 



g) Pigeons. — Gahringer^ reports sensitization of pigeons, at times sufficiently 

 high to give lethal anaphylaxis, by a single intravenous injection with 0.2 5-cc. dog 

 serum. Slight sensitization was observed as early as the fourth day after the injec- 

 tion, with maximum sensitization about the fourteenth day. After the twentieth day 

 the sensitization gradually decreased, practically disappearing by the seventieth day. 



h) Monkeys. — Zinsser^ reports slight sensitization of monkeys, following multiple 

 intravenous injections with egg white. 



i) Frogs. — Friedberger and Mita^ report lethal sensitization of summer frogs fol- 

 lowing a single intravenous (abdominal vein) or intralymphatic (dorsal lymph sac) 

 injection of 0.1-0.5-cc. sheep serum. The frogs were tested after an incubation period 

 of one to four weeks. Winter frogs are apparently not capable of sensitization. 



PASSIVE SENSITIZATION 



a) Guinea pigs. — Normal guinea pigs may be passively sensitized sufficiently to 

 give lethal anaphylaxis, by a subcutaneous, intraperitoneal, or intravenous injection 

 with a sufficiently large dose of the serum, defibrinated blood or whole blood of an 

 actively sensitized or an actively immunized guinea pig. Slight hypersensitiveness is 

 usually demonstrable after a latent period of from six to ten hours, and lethal sen- 

 sitization in about twenty-four hours. Kellaway and Cowell^ found that maximum 

 sensitization is not reached before the fourth to the sixth day. Homologous passive 

 sensitization usually disappears spontaneously in about thirty days. 



Passive sensitization of guinea pigs is at times possible with the serum or tissue 

 products of other animal species. Thus, guinea pigs may be sensitized even sufficient- 

 ly to give lethal anaphylaxis,* by subcutaneous, intraperitoneal, or intravenous in- 

 jections with rabbit antiserum. They cannot be sensitized, however, with rat anti- 

 serum.' 



' Manwaring, W. H. : Ztschr.f. Immiinitatsforsch. 21. exper. Therap., 8, i. 19 ro; Schultz, W. H.: 

 J. Pharmacol. b° Exper. Therap., 3, 299. 191 1; Drinker, C. K., and Bronfenbrenner, J.: loc. ci'L 

 ' Parker, J. T. and F.: /. Med. Research, 44, 263. 1924. 



3 Schiemann, O., and Meyer, H.: Ztschr.f. Hyg. u. Infektionskrankh., 106, 607. 1926. 

 ^ Gahringer, J. E.: /. Immunol., 12, 477. 1926. 

 5 Zinsser, H.: Proc. Soc. Exper. Biol, b" Med., 18, 57. 1920. 



* Friedberger, E., and Mita, S.: Ztschr.f. Immiinitdtsforsch. n. exper. Therap., lo, 362. 191 1. 

 ' Kellaway, C. H., and Cowell, S. J.: Brit. J. Exper. Path., 4, 255. 1923. 



* Doerr, R., and Russ, V. K.: Ztschr.f. Immunitatsforsch. u. exper. Therap., 2, 109. 1909. 

 9 Parker, J. T. and F.: loc. cit. 



