This invention relates to the A3R5.7 (designated A3R5) cell line that supports the detection of HIV-1-specific neutralization by mAbs, sCD4 and polyclonal plasma across wide range of epitopes on the HIV-1 envelope.

Applications and Advantages

• Tool for analysis of neutralization activity in HIV vaccine trials
• Supports an extensive range of HIV-1 clones
• Assay showed greater neutralization sensitivity over the TZM-bl based assay

Innovation Description

Sensitive assays are needed to meaningfully assess low levels of neutralizing antibodies (NAbs) that may be important for protection against the acquisition of HIV-1 infection in vaccine recipients. The current assay of choice uses a non-lymphoid cell line (TZM-bl) that may lack sensitivity owing to over expression of CD4 and CCR5.

Researchers at the Henry M. Jackson Foundation (HJF) and the Walter Reed Army Institute of Research (WRAIR) used transfection of a humanlymphoblastoid cell line (A3.01) to stably express CCR5. The resulting line, designated A3R5, is permissive to a wide range of circulating strains of HIV-1, including HIV-1 molecular clones that express multiple Env subtypes. It supports the detection of HIV-1-specific neutralization by mAbs, sCD4 and polyclonal plasma from multiple subtypes encompassing a range of epitopes on the HIV-1 envelope with sensitivity greater than observed in the TZM-bl line (Fig.1).

Fig. 1 Neutralization sensitivity was significantly greater in the A3R5 cell line compared to TZM-bl against tested virus/sera.

Inventors

• COL(ret.) Jerome H. Kim, MD., WRAIR
• Robert J. McLinden, Ph.D., HJF

Innovation Status

Characterization by flow cytometry and epitope-specific inhibitor neutralization studies has been completed. Please see PLOS ONE 8(11), 2013: e77756

Intellectual Property Status

Licensed as a Biological Material or Research Tool