In situ immunization

Abstract

The arming of activated T cells (ATC) with BiAbs can overcome major barriers for successful adoptive immunotherapy. The BiAb approach takes the advantage of the targeting specificity of monoclonal antibodies and the cytotoxic capacity of T cells to lyse tumors. Arming of ATC with BiAb makes every T cell an antigen-specific CTL and infusions of such cells will markedly increase the effective precursor frequency of CTL in the cancer patient. Furthermore, the ability of such armed ATC to kill multiple times without rearming with BiAb, secrete tumoricidal cytokines, secrete chemokines, and survive in patients for up to 8 days after the last infusion or in Beige/SCID mice for over 13 weeks after cessation of treatment. The persistence of cells in the Beige/SCID after infusion show long-term survival capability in the host. Re-stimulation of armed ATC after 3 cycles of cytotoxicity with tumor cells resulted in the secretion of interferon gamma indicating the development of tumor specific immune responses in the population of cells that have been exposed multiple times to antigen. In summary, armed ATC can act as a cytotoxic “drug”, kill multiple times (direct killing), divide after killing (increasing the effector:target ratio in vivo), secrete tumoricidal cytokines (indirectly killing), secrete chemokines at the tumor site (recruit naive T cells and antigen-presenting cells to immunize the patient to tumor lysate) and persist in patients and animal models for weeks to months (long-term survival).

1 . A method for treatment of a patient suffering from cancer, said method comprising the steps of:
 (a) isolating peripheral blood mononuclear cells comprising T cells;   (b) activating the T cells by ex vivo stimulation, and expanding said activated T cells;   (c) arming of activated T cells with bispecific antibodies capable of binding to the T cell receptor complex of a T cell and/or Fc-receptor positive cells, and to tumor-associated antigens on a tumor cell, wherein the bispecific antibodies redirect the activated T cells to kill the tumor cells by binding to the tumor cells and triggering the secretion of tumoricidal cytokines and chemokines; and,   (d) infusing a composition comprising the armed, activated T cells into the patient in a therapeutically effective amount able to
 (i) target and contact multiple tumor cells with the armed activated T cells to which the bispecific antibody remains bound and 
 (ii) kill the tumor cells by secreting cytokines. 
   
     
     
         2 . The method of  claim 1 , wherein said method further comprises co-infusing intravenously or co-injecting into a tumor arterial supply or tumor site a composition of dendritic cells with the armed, activated T cells. 
     
     
         3 . (canceled) 
     
     
         4 . The method of  claim 2 , wherein the armed, activated T cells are coinfused with IL-2, IL-12, GM-CSF or other immune augmenting cytokines. 
     
     
         5 . (canceled) 
     
     
         6 . The method according to  claim 1 , wherein the bispecific antibody is comprised of two monoclonal antibodies. 
     
     
         7 . The method according to  claim 6 , wherein each of the specificities of said bispecific antibody are directed to a tumor antigen and the T cell receptor complex. 
     
     
         8 . The method according to  claim 6 , wherein the monoclonal antibodies are chemically heteroconjugated to form the bispecific antibody. 
     
     
         9 . The method according to  claim 1 , wherein the bispecific antibody is comprised of monoclonal antibodies directed to any tumor associated antigen. 
     
     
         10 . The method according to  claim 1 , wherein the anti-T cell receptor monoclonal antibody component of said bispecific antibody is directed against CD3 of the T cell receptor complex. 
     
     
         11 . The method according to  claim 1 , wherein the T cell-mediated cytotoxicity of a tumor occurs in immunosuppressed patients. 
     
     
         12 . The method according to  claim 1 , wherein T cell-mediated cytotoxicity occurs in patients susceptible to, or suffering from diseases associated with abnormal cellular proliferation or growth. 
     
     
         13 . The method according to  claim 1 , wherein the armed T cell can be frozen and thawed for use in a patient in need of such therapy. 
     
     
         14 . The method according to  claim 1 , wherein the T cell is armed with a bispecific antibody dose of between about 0.5 ng per million T cells to between about 500 ng per million T cells. 
     
     
         15 . The method of  claim 14 , wherein the arming dose is optimized for each individual patient by titrating a thawed aliquot of the patients activated T cells to achieve a percent specific cytotoxicity level at an effector to target ratio from between about 25:1 to at least about 30% against a tumor target. 
     
     
         16 . The method of  claim 15 , wherein the infusing dose is at least about 2 billion armed T cells. 
     
     
         17 . The method of  claim 15 , wherein the patient receives at least about four infusions. 
     
     
         18 . The method according to  claim 1 , wherein the T cell is CD3/CD8 positive. 
     
     
         19 . The method according to  claim 1 , wherein the T cell is a CD3/CD4 positive cell. 
     
     
         20 . The method according to  claim 1 , wherein the armed T cells from a patient can be co-administered with other forms of therapy and/or immunocompetent nave T cells, and immunocompetent nave B cells. 
     
     
         21 - 89 . (canceled) 
     
     
         90 . A method for treatment of a patient suffering from cancer, said method comprising the steps of:
 (a) isolating peripheral blood mononuclear cells comprising T cells;   (b) activating of the T cells by ex vivo stimulation and expanding of said activated T cells;   (c) arming of activated T cells with bispecific antibodies capable of binding to the T cell receptor complex of a T cell and/or Fc-receptor positive cells, and to tumor-associated antigens on a tumor cell, wherein the bispecific antibodies redirect the activated T cells to kill the tumor cells by binding to the tumor cells and triggering the secretion of tumoricidal cytokines and chemokines; and,   (d) infusing a composition comprising the armed, activated T cells into the patient in a therapeutically effective amount able to
 (i) target and contact multiple tumor cells with the armed activated T cells to which the bispecific antibody remains bound and 
 (ii) kill the tumor cells by secreting cytokines. 
   
     
     
         91 . The method of  claim 90 , wherein the armed, activated T cells are coinfused with IL-2, IL-12, GM-CSF or other immune augmenting cytokines. 
     
     
         92 . The method according to  claims 91 , wherein the bispecific antibody is comprised of two monoclonal antibodies. 
     
     
         93 . The method according to  claim 92 , wherein each of the specificities of said bispecific antibody are directed to a tumor antigen and the T cell receptor complex. 
     
     
         94 . The method of  claim 90 , wherein the autologous cells induce the proliferation of T cells specific for different epitopes on the tumor cell. 
     
     
         95 . The method of  claim 90 , wherein the bispecific antibody remains bound to the armed T cell allowing the armed T cell to target and kill multiple target cells which the armed T cell recognizes the desired antigens on the target cells. 
     
     
         96 - 105 . (canceled)