Production of biological carriers for induction of immune response and inhibition of viral replication

Abstract

This application provides a method to form non-infectious Biological Carrier that may be used to deliver signals to cells either in vitro or in vivo. The Biological Carriers are inactivated virus particles that have been specifically modified to give biological properties different from the virus particles deriving from an unmodified host cell that (i) expresses at least one co-stimulatory molecule and (iia) at least one antigen that can initiate an immune response, and/or (iib) express surface molecules that suppress viral replication.

1 . A method of activating a naïve T-lymphocyte to an antigen which comprises contacting the T-lymphocyte with a non-infectious biological carrier comprising
 a Human Immunodeficiency Virus (HIV) viral or viral-like particle that   (i) presents at least one exogenous antigen incorporated into said particle such that said at least one antigen initiates an immune response;   (ii) also expresses at least one exogenous antigen fragment bound to a primary host cell surface molecule selected from MHC I and MHC II; and   (iii) also expresses at least one B7 molecule as a co-stimulatory molecule.   
   
   
       2 . A method of inhibiting virus expression, independent of mechanism, which comprises contacting cells with a non-infectious biological carrier comprising
 a Human Immunodeficiency Virus (HIV) viral or viral-like particle that   (i) presents at least one exogenous antigen incorporated into said particle such that said at least one antigen initiates an immune response;   (ii) also expresses at least one exogenous antigen fragment bound to a primary host cell surface molecule selected from MHC I and MHC II; and   (iii) also expresses at least one B7 molecule as a co-stimulatory molecule.   
   
   
       3 . A method for determining the state of activation of a T-lymphocyte population to a particular antigen by contacting the T-lymphocyte population with a non-infectious biological carrier comprising
 a Human Immunodeficiency Virus (HIV) viral or viral-like particle that   (i) presents at least one exogenous antigen incorporated into said particle such that said at least one antigen initiates an immune response;   (ii) also expresses at least one exogenous antigen fragment bound to a primary host cell surface molecule selected from MHC I and MHC II; and   (iii) also expresses at least one B7 molecule as a co-stimulatory molecule.   
     and observing any change in an indicator of the state of activation of T-lymphocytes in the T-lymphocyte population.