4()8 LOCAL TLSSUE RKACniVLIY 



j)crl()riiic(l on the same altei noon, i.e., about six or ci,t>lit hours 

 alter tlie trial bleeding. 



A sudden rise or drop in concentration ol the plienonienon- 

 neutralizing antibodies is a conspicuous feature and may be ob- 

 served during various periods of luiinterrupted immunization. 

 Once a drop occurs, continuation of imminiization is frequently 

 valueless. A rest of several Aveeks or months may reestablish the 

 ability of a horse to produce neutralizing antibodies. After the 

 rest period one or more injections are frequently snfficient to 

 bring about a high concentration of antitoxin, ^vhich in turn 

 may promptly drop again after an additional injection. Rises and 

 drops in concentration of the antil)odies can be elicited several 

 times in the same horse by alternating periods of immunization 

 \\'ith periods of rest. The toxic filtrates alone without the aid of 

 vaccines are capable of stimulating the production of neutralizing 

 antibodies as \vell as of agglutinins and precipitins. 



The imminie seriun used for treatment of most of the cases 

 about to be described contained bet^veen looo to 1200 neutraliz- 

 ing iniits per 1 c.c. The serum also showed complete agglutina- 

 tion in dilutions as high as 1:25,600 and markedly precipitated 

 the B. typJiosiis "agar washings" filtrates in dilutions as high as 

 1:32. 



Clinical observations with phenomenon-neutralizing anti- 

 typhoid horse serum: 



Clinical observations were carried out in the Mt. Sinai Hos- 

 pital (N. Y.) and the Charity Hospital, New Orleans, in collabo- 

 ration Avith Drs. Geor"e Baehr and \V. Y. Hollinosworth, Surgeon 

 of the Lhiited States Public Health Service. Seventy-eight cases of 

 typhoid fever received from 100 to 500 c.c. of the immune serum 

 intravenously. If intradermal or ophthalmic tests revealed definite 

 sensitivity no serum was given. Treated patients received a pre- 

 liminary injection of 10 c.c, followed three horns later by 25 c.c. 

 If there ^vere no mito^vard symptoms 50 c.c. 'were administered 

 by slow intra\enous drop. Either of these procedmes \vas repeated 

 at intervals of four to eight hours \vith similar amounts mitil the 

 total dose ^vas introduced. The usual complications of intra\e- 

 nous serum therapy Avere encoimtered and are reported in detail 

 later. 



Effect uJ)on toxemia. Thirty-nine, or 50 per cent of the patients 

 sho\\ed relief from toxemia followino serum. In some of the cases 



