Strong T cell type-1 immune responses to HIV-1 Tat (1-72) protein-coated nanoparticles

Vaccine. 2004 Jun 30;22(20):2631-40. doi: 10.1016/j.vaccine.2003.12.013.

Abstract

A significant emphasis has been placed on the development of adjuvants and/or delivery systems to improve both antibody production and cell-mediated immune responses. We previously reported on a novel anionic nanoparticle, which led to enhanced humoral and T helper type-1 (Th1) biased immune responses in mice when coated with cationized model antigen. Tat (1-72) is a conserved regulatory HIV-1 protein. It was hypothesized that HIV vaccine strategies employing Tat (1-72) may be a promising approach. Although previous reports have suggested that Tat (1-86) may be immunosuppressive, it was demonstrated in this present study that Tat (1-72) was not immunosuppressive when co-administered to mice with ovalbumin (OVA). Tat (1-72) was coated on novel anionic nanoparticles. BALB/c mice were immunized with Tat (5 microg)-coated nanoparticles (15 microg) by subcutaneous injection on days 0 and 14. Antibody and cytokine release were determined on day 28 and compared to Tat (5 microg) adjuvanted with Alum (15 microg) as a Th2 control, Tat (5 microg) adjuvanted with Lipid A (50 microg) as a Th1 control. Immunization of BALB/c mice with Tat-coated nanoparticles resulted in antibody levels (IgG and IgM) comparable to those elicited from Tat and Alum. However, Tat-coated nanoparticles led to a Th1 biased immune response. The IFN-gamma release from splenocytes with Tat-coated nanoparticles was comparable to that from mice immunized with Tat and Lipid A, and 3.3-fold greater than that from mice immunized with Tat and Alum. These studies warrant further investigation of these nanoparticles to enhance both antibody and cellular-based immune responses.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • AIDS Vaccines / immunology*
  • Animals
  • Animals, Genetically Modified
  • Immunoglobulin G / blood
  • Immunoglobulin M / blood
  • Mice
  • Mice, Inbred BALB C
  • Nanotechnology
  • Particle Size
  • T-Lymphocytes / immunology*

Substances

  • AIDS Vaccines
  • Immunoglobulin G
  • Immunoglobulin M
  • human immunodeficiency virus type 1 Tat vaccine