Fluorescence resonance energy transfer screening assay for the identification of HIV-1 envelope glycoprotein-medicated cell

Abstract

This invention provides: agents determined to be capable of specifically inhibiting the fusion of a macrophage-tropic primary isolate of HIV-1 to a CD4 + cell, but not a T cell-tropic isolate of HIV-1 to a CD4 + cell; and agents determined to be capable of specifically inhibiting the fusion of a T cell-tropic isolate of HIV-1 to a CD4 + cell, but not a macrophage-tropic primary isolate of HIV-1 to a CD4+ cell. This invention also provides: agents capable of specifically inhibiting the fusion of a macrophage tropic primary isolate of HIV-1 with a CD+ cell susceptible to infection by a macrophage-tropic primary isolate of HIV-1; and agents capable of specifically inhibiting the fusion of a T cell-tropic isolate of HIV-1 with a CD4 + cell susceptible to infection by a T cell-tropic isolate of HIV-1. The agents include but are not limited to antibodies. This invention further provides: methods of inhibiting fusion of a macrophage-tropic primary isolate of HIV-1 with a CD4 + cell susceptible to infection by a macrophage-tropic primary isolate of HIV-1 which comprises contacting the CD4 + cell with an amount of an agent capable of specifically inhibiting such fusion so as to thereby inhibit such fusion; and methods of inhibiting fusion of a T cell-tropic isolate of HIV-1 with a CD4 + cell susceptible to infection by a T cell-tropic isolate of HIV-1 which comprises contacting the CD4 + cell with an amount of an agent capable of specifically inhibiting such fusion so as to thereby inhibit such fusion.

1 - 6 . (canceled) 
   
   
       7 . A method for determining whether an HIV-1 test isolate is a macrophage-tropic HIV-1 isolate, which comprises:
 (a) contacting a first CD4+ cell susceptible to infection by a macrophage-tropic HIV-1 isolate with an envelope glycoprotein of the HIV-1 test isolate;   (b) determining whether the envelope glycoprotein fuses to the first CD4+ cell;   (c) contacting a second CD4+ cell susceptible to infection by a T cell-tropic HIV-1 isolate with the envelope glycoprotein of the HIV-1 test isolate; and   (d) determining whether the envelope glycoprotein fuses to the second CD4+ cell,   
     wherein fusion in step (b) but not in step (d) indicates that the HIV-1 test isolate is a macrophage-tropic isolate of HIV-1. 
   
   
       8 . The method of claim  1 , wherein the HIV-1 envelope glycoprotein is present on the surface of a cell. 
   
   
       9 . The method of claim  1  or claim  2 , wherein the first CD4+ cell is the same type of cell as the second CD4+ cell. 
   
   
       10 . The method of claim  1  or claim  2 , wherein the first CD4+ cell susceptible to infection by a macrophage-tropic HIV-1 is a PM1 cell, a primary human T lymphocyte, or a primary human macrophage. 
   
   
       11 . The method of claim  1  or claim  2 , wherein the second CD4+ cell susceptible to infection by a T cell-tropic HIV-1 is a HeLa-CD4 cell, a primary human T lymphocyte, a human T cell line, a PM1 cell, or a C8166 cell. 
   
   
       12 . The method of claim  1  or claim  2 , wherein the envelope glycoprotein of the macrophage-tropic HIV-1 isolate is an HIV-1 JR-FL  gp120/gp41 envelope glycoprotein. 
   
   
       13 . The method of claim  1  or claim  2 , wherein the envelope glycoprotein of the macrophage-tropic HIV-1 isolate is HIV-1 JR-FL  gp120/gp41 envelope glycoprotein expressed in a cell.