Compositions, kits and methods for in vitro antigen presentation, assessing vaccine efficacy, and assessing immunotoxicity of biologics and drugs

A method of detecting an immune response against a vaccine, the method comprising the steps of:

• a) preparing or providing a composition comprising a plurality of charged highly branched polymeric dendrimers each having conjugated thereto at least one universal DR binding peptide and at least one peptide or polypeptide antigen or a nucleic acid encoding the at least one antigen, wherein the at least one universal DR binding peptide and the nucleic acid or at least one peptide or polyeptide antigen are conjugated to the exterior surface of the plurality of charged highly branched polymeric dendrimers such that the at least one universal DR binding peptide specifically binds to professional antigen presenting cells (PAPCs),
• wherein the vaccine comprises the antigen;
• b) obtaining a first sample comprising PAPCs from the subject prior to vaccination of the subject;
• c) dividing the first sample into a first portion of the first sample and a second portion of the first sample;
• d) contacting the first portion of the first sample with the composition under incubation conditions such that the plurality of charged highly branched polymeric dendrimers are taken up by the PAPCs and such that the antigen is processed by the PAPCs and presented by the PAPCs in combination with MHC class II;
• e) washing the first portion of the first sample and the second portion of the first sample;
• f) combining the first portion of the first sample and the second portion of the first sample at two or more ratios, resulting in a first plurality of mixtures;
• g) incubating the first plurality of mixtures for one or more hours;
• h) examining the plurality of mixtures for the presence of at least one molecule or marker that is indicative of an immune response to the vaccine and determining the level of the at least one molecule or marker;
• i) obtaining a second sample comprising PAPCs from the subject after the subject has been vaccinated;
• j) dividing the second sample into a first portion of the second sample and a second portion of the second sample;
• k) contacting the first portion of the second sample with the composition under incubation conditions such that the plurality of charged highly branched polymeric dendrimers are taken up by the PAPCs in the first portion of the second sample and such that the antigen is processed by the PAPCs in the first portion of the second sample and presented by the PAPCs in the first portion of the second sample in combination with MHC class II;
• l) washing the first portion of the second sample and the second portion of the second sample;
• m) combining the first portion of the second sample and the second portion of the second sample at two or more ratios, resulting in a second plurality of mixtures;
• incubating the first plurality of mixtures for one or more hours;
• n) examining the second plurality of mixtures for the presence of the at least one molecule or marker and determining the level of the at least one molecule or marker;
• o) comparing the level of the at least one molecule or marker in the first plurality of mixtures with the level of the at least one molecule or marker in the second plurality of mixtures;
• and
• p) correlating a higher level of the at least one molecular or marker in the second plurality of mixtures than in the first plurality of mixtures with an immune response to the vaccine.