Method for inducing a cell-mediated immune response and improved parenteral vaccine formulations thereof

Abstract

A method of inducing either a T H 1 polarised immune response, a T H 2 polarised immune response or a combined T H 1 and T H 2 response to an antigen and associated vaccine formulations are disclosed. A method is provided for inducing a polarised T H 1 response by parenteral administration of microparticles sized such that at least 50% of the microparticles are less than 5 μm, the microparticles containing antigen entrapped or encapsulated by a biodegradable polymer. Additionally, a method is provided for inducing a polarised T H 2 response by parenteral administration of nanoparticles sized such that at least 50% of the nanoparticles are less than 600 nm, the nanoparticles containing antigen entrapped or encapsulated by a biodegradable polymer. Vaccine formulations containing the B. pertussis antigens PTd, FHA or a combination of PTd and FHA are provided.

1 . A method of inducing a T H 2 polarised immune response to an antigen, comprising parenterally administering to a subject nanoparticles sized such that at least 50% of the nanoparticles are less than 600 nm, the nanoparticles comprising the antigen entrapped or encapsulated by a biodegradable polymer. 
     
     
         2 . The method of  claim 1 , wherein the nanoparticles are sized such that at least 50% of the nanoparticles are less than 500 nm. 
     
     
         3 . The method of  claim 1 , wherein the biodegradable polymer comprises a copolymer of lactic acid and glycolic acid or enantiomers thereof. 
     
     
         4 . The method of  claim 1 , wherein the nanoparticles are formed using a coacervation method. 
     
     
         5 . The method of  claim 1 , wherein the antigen comprises a  B. pertussis  antigen. 
     
     
         6 . The method of  claim 1 , wherein the parenteral administration is selected from the group consisting of intraperitoneal administration, subcutaneous administration and intramuscular administration.