Challenges in Designing HIV Env Immunogens for Developing a Vaccine - Structure-Based Study of Viral Replication - page 362

was achieved. 186 Similar observations were made with a DNA prime
and rAdeno virus boost regimen by Letvin and colleagues. 187 In a
proof of concept study, we immunized a group of rabbits with HIV-
1 Envs derived from subtype-B and subtype-C isolates either alone or
in combination in a DNA prime and protein boost regimen. All of the
animals immunized either alone or with the bivalent B and C vaccine
induced comparable levels of antibody responses against subtype-B
and subtype-C envelope proteins in ELISA. The antibodies induced
in the bivalent group were able to neutralize both homologous sub-
type-B and subtype-C isolates as well as other B and C strains. 150
Acknowledgments
We would like to thank Dr Rino Rappuoli, Vice President, Novartis
Vaccines and Diagnostics, Inc. for his encouragement and support of
the HIV vaccine development project, and Dr Susan Barnett (HIV
Project Leader) and Dr Jeffrey Ulmer (Head, Immunology and Cell
Biology) for their valuable contributions. We would also like to thank
K.C. Egan for their expert editorial help and Mike Peterson for
administrative help and support. HIV vaccine work is supported by
NIAID-NIH contracts and grants (AI-95367; I-AI-05396 and
5 PO1 AI48225-03), as well as the Discovery Fund.
References
1. UNAIDS/WHO. (2004) 2004 Report on the global AIDS epidemic.
Online.
2. Mascola JR, Mathieson BJ, Zack PM, et al . (1993) Summary report:
workshop on the potential risks of antibody-dependent enhancement
in human HIV vaccine trials. AIDS Res Hum Retroviruses 9 :
1175-1184.
3. Mascola JR, Snyder SW, Weislow OS, et al . (1996) Immunization with
envelope subunit vaccine products elicits neutralizing antibodies
against laboratory-adapted but not primary isolates of human immun-
odeficiency virus type 1. The National Institute of Allergy and
Infectious Diseases AIDS Vaccine Evaluation Group. J Infect Dis 173 :
340-348.