Immunization strategies for high affinity immune response (106.48)

In the field of hybridoma development immunization strategies involving varied mouse strains, adjuvants and immunogens have been widely reported with diverse results. We describe here studies completed to evaluate two arms of the immunization strategy - adjuvant selection and hapten-to-carrier ratio. First, Titanium Powder Adjuvant (TPA) and 2-Dose Adjuvant (2DA) were evaluated vs. our standard adjuvant, Adjulite Freund’s Adjuvant (AFA), for resulting antibody titer and affinity by immunizing with either insulin or hepatitis B surface antigen (HBsAg). Second, mice were immunized with the hapten neopterin linked to BSA using a 23:1 or 4:1 coupling ratio. CAF1/J and RBF/DnJ mice were employed for both studies. Adjuvant study results showed a higher titer and higher affinity response using AFA vs. TPA. While all mice immunized with HBsAg developed an immune response, those immunized using AFA showed a significantly higher average relative affinity than those immunized using TPA. Additionally, for CAF1/J mice immunized with insulin, only those using AFA developed an immune response. The 2DA mice yielded a relative affinity similar to the AFA mice. In the hapten-to-carrier ratio study mice immunized with hapten coupled using a 4:1 ratio yielded a significantly higher average affinity. We continue to evaluate all arms of the immune response strategy to ensure a high affinity immune response by testing new adjuvants and animal models.