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PubMed · 11683574

Overcoming original (antigenic) sin.

D E Anderson·M P Carlos·L Nguyen·J V Torres
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Abstract

Original antigenic sin describes a phenomenon in which the antibody response elicited in an individual after a secondary viral infection reacts more strongly to the viral variant that originally infected the individual. As T helper cells play critical roles in promoting antibody responses, a similar phenomenon may hold true for T helper cell responses. This concept is particularly relevant to the development of vaccines against viruses such as human immunodeficiency virus and hepatitis C virus, in which myriad viral variants are present throughout the human population. We have compared the effects of priming the immune system with a single peptide epitope or with a cocktail of related peptides based on the epitope. Our data demonstrate that immunization with multiple peptide variants expands a more broadly reactive and durable T helper cell response than does immunization with a single peptide. This vaccine strategy may circumvent original antigenic sin.

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AIDS VaccinesAmino Acid SequenceAnimalsHIV Envelope Protein gp120HIV-1ImmunizationImmunologic MemoryMiceMice, Inbred BALB CMolecular Sequence DataT-LymphocytesT-Lymphocytes, Helper-InducerJournal Article

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D E Anderson, M P Carlos, L Nguyen, J V Torres. 2001. Overcoming original (antigenic) sin.. https://doi.org/10.1006/clim.2001.5114

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