Protein d - an igd-binding protein of haemophilus influenzae

Abstract

A novel surface exposed protein of Haemophilus influenzae or related Haemophilus species is described. The protein named protein D is an Ig receptor for human IgD and has an apparent molecular weight of 42,000. Protein D can be detected in all of 116 encapsulated and non-encapsulated isolates of H. influenzae studied. The protein from all strains shows in addition to the same apparent molecular weight immunogenic similarities since protein D from all strains interacts with three different mouse monoclonal antibodies and monoclonal human IgD. A method for purification of protein D is described. Cloning of the protein D gene from H. influenzae in E. coli is described as well as the nucleotide sequence and the deduced amino acid sequence.

1 - 16 . (canceled) 
     
     
         17 . A hybridoma cell capable of producing a monoclonal antibody to an immunogenic portion of a surface exposed protein of  Haemophilus influenzae  or related  Haemophilus  species, said protein having an apparent molecular weight of 42,000 and a capacity of binding human IgD. 
     
     
         18 . A purified antibody which is specific to an immunogenic portion of a surface exposed protein of  Haemophilus influenzae  or related  Haemophilus  species, said protein having an apparent molecular weight of 42,000 and a capacity of binding human IgD. 
     
     
         19 . A method of detecting the presence of  Haemophilus influenzae  or related  Haemophilus  species in a sample by contacting said sample with the antibody of  claim 18  in the presence of an indicator. 
     
     
         20 - 22 . (canceled)