Antigenic preparations and isolation of such preparations

Abstract

The present invention provides novel antigenic preparations comprising proteinaceous material associated with adenylate cyclase activity in cultures of B.pertussis, the said preparations being useful as components of acellular whooping cough vaccines. The invention further provides methods for the isolation of such antigenic preparations.

1 . A vaccine formulation for protection against  Bordetella pertussis  which includes an antigenic preparation derived from  B. pertussis  comprising proteinaceous material associated with adenylate cyclase activity (ACAP) together with a pharmaceutically acceptable carrier therefor.  
     
     
         2 . A vaccine formulation as claimed in  claim 1  wherein the said ACAP has a relative molecular weight (MW) of 67,000-73,000.  
     
     
         3 . A vaccine formulation according to  claim 1  wherein the said ACAP has a MW of substantially 69,000.  
     
     
         4 . A vaccine formulation according to  claim 1  wherein the said ACAP has an isoelectric point (pl) of 7.0-7.4 under preparative isoelectric focussing (IEF) conditions.  
     
     
         5 . A vaccine formulation according to  claim 4  wherein the said ACAP has a pl of substantially 7.0.  
     
     
         6 . A vaccine formulation according to  claim 1  wherein the ratio of proline to glutamic acid residues in the said ACAP is substantially 1:1.  
     
     
         7 . A vaccine formulation according to  claim 1  wherein the tyrosine residues contained in the said ACAP are not iodinctable.  
     
     
         8 . A vaccine formulation according to  claim 1  substantially free from intracelluler material derived from  B.pertussis.    
     
     
         9 . A vaccine formulation according to  claim 1  further comprising a pharmaceutically acceptable adjuvant.  
     
     
         10 . A vaccine formulation according to  claim 1  further comprising one or more other antigenic components.  
     
     
         11 . A method for the isolation of an antigenic preparation containing ACAP from  B. pertussis  which comprises treating a culture of  B.pertussis  cells with an aqueous amino acid buffer of pH 2.5-3.5, comprising a hypertonic concentration of said amino acid with respect to the cells, separating the cells from the resulting supernatant and isolating an antigenic preparation containing ACAP from the supernatant.  
     
     
         12 . A method according to  claim 11  wherein the amino acid is selected from glycine and alanine.  
     
     
         13 . A method according to  claim 11  wherein the said isolation from the supernatant comprises ion exchange chromatography.  
     
     
         14 . A method according to  claim 11  wherein the said isolation from the supernatant comprises isoelectric focussing.  
     
     
         15 . A method to either of claims  13  and  14  wherein the said isolation further comprises passage of the isolated material through an immunosorbent column comprising an appropriate monoclonal antibody against the said ACAP.  
     
     
         16 . A vaccine formulation according to any of  claims 1  to  10  wherein the said ACAP is prepared by a method according to any of  claims 11  to  15 .  
     
     
         17 . ACAP.  
     
     
         18 . Proteinaceous material according to  claim 21  characterised in that it has the following properties:- 
 (i) A ratio of proline to glutamic acid of substantially 1:1;  
 (ii) the tyrosine residues are not iodinatable;  
 (iii) substantially free from intracellular,  B.pertussis  material;  
 (iv) a relative molecular weight of 67,000 to 73,000;  
 (v) an isoelectric point of 7.0 to 7.4, and  
 (vi) being acid-labile below a pH of about 3.  
 
     
     
         19  A method for inducing immunity to whooping cough in a susceptible vertebrate host comprising the administration of ACAP as claimed in either of claims  17  and  18 .  
     
     
         20 . A method according to  claim 19  wherein the said ACAP is in the form of a vaccine.  
     
     
         21 . A method according to  claim 19  wherein the said ACAP is in the form of a vaccine and the host is human.