316 DIFCO MANUAL 



BAGTO-KAHN BEEF HEART (B223) 



Bacto-Kahn Beef Heart^-^'^**'^ is recommended particularly for the preparation 

 of antigens for use in the Kahn tests for the diagnosis of syphilis and for use in 

 the Kahn Universal Reaction. Dried beef heart, even when stored in the refrig- 

 erator, may undergo changes which render it unsatisfactory for use in preparing 

 antigens for the Kahn procedures, although it continues to be satisfactory for use 

 in the preparation of other antigens. Bacto-Kahn Beef Heart is prepared spe- 

 cifically for use in the preparation of Kahn antigens. No lot is released for dis- 

 tribution until it has been found satisfactory for the preparation of Kahn Stand- 

 ard Antigen and Kahn Sensitized Antigen in Dr. Kahn's laboratory. Bacto-Kahn 

 Beef Heart should be stored in the refrigerator at all times. 



The antigens employed in the Kahn tests are stable. For that reason Bacto- 

 Kahn Beef Heart should be converted into antigen as soon as the material has 

 been received from our laboratories. A description of the method of preparation 

 of Kahn Standard Antigen and Kahn Sensitized Antigen is available upon 

 request. 



iKahn: The Kahn Test, A Practical Guide, SKahn: The Kahn Test, A Practical Guide, 



Chapter 3:1928. Chapter 4:1928. 



3 Kahn: Technique of the Standard Kahn * Am. J. Clin. Path., 17:117:1947. 



Test, Univ. Mich. Press, p. 39, I944- ^ Kahn, Serology with Lipid Antigen, 271:1950. 



BAGTO-GHOLESTEROL ( B224) 



Bacto-Cholesterol is prepared especially for cholesterolizing antigens. It is of 

 the highest purity and is ash free. 



The addition of pure cholesterol to reenforce antigens was first recommended 

 by Sachs. ^ By this means, antigens are rendered more sensitive without increasing 

 their anticomplementary or hemolytic powers. 



Bacto-Cholesterol is also recommended for use as a standard in blood cho- 

 lesterol and other cholesterol determinations. 



^ Klin. Wochschr., Berlin, 48:2066:1911. 



BAGTO-GORN GERM STEROL (B225) 



Bacto-Com Germ Sterol is a highly purified reagent which was developed in 

 cooperation with Dr. Eagle for use as a sensitizing agent in the antigen for his 

 tests. 



This sterol is used in conjunction with Bacto-Cholesterol by Eagle^ in the 

 antigen for his flocculation technique for syphilis. In positive sera the crystalline 

 aggregates are large and readily lend themselves to detection. 



ij. Lab. Clin. Med., 17:787:1932. 



KAHN OVERSENSITIVE GORREGTION SOL'N. (B448) 

 KAHN UNDERSENSITIVE GORREGTION SOL'N. ( B449 ) 



Bacto-Kahn Oversensitive Correction Solution and Bacto-Kahn Undersensitive 

 Correction Solution are used for the correction of oversensitive and under- 

 sensitive alcoholic extracts of Bacto-Kahn Beef Heart in the preparation of Kahn 

 Standard Antigen and Kahn Sensitized Antigen as described by Wheeler, 

 Brandon and Kahn^'- and Wheeler and Brandon.^ 



1 Am. J. Clin. Path., 17:117:1947. 

 ^ Am. J. Clin. Path., 17:130:1947. 



2 Am. J. Clin. Path., 17:770:1947. 



