Enhanced Expansion of Tumor-Infiltrating Lymphocytes for Adoptive Cell Therapy

Abstract

Disclosed herein is a method for ex vivo expanding tumor-infiltrating lymphocytes for use in adoptive cell therapy (ACT). The method involves culturing tumor fragments from the subject in a culture medium containing IL-2 and a 41BB agonist in an amount effective to expand tumor-infiltrating lymphocytes with enriched tumor-reactivity and specificity. Also disclosed is a method for treating a tumor in a subject that involves treating the subject with nonmyeloablative lymphodepleting chemotherapy, and administering tumor-infiltrating lymphocytes expanded by the disclosed methods.

1 . A method for ex vivo expanding tumor-infiltrating lymphocytes for use in adoptive cell therapy (ACT), comprising culturing tumor fragments from the subject in a culture medium comprising IL-2 and a 41BB agonist in an amount effective to expand tumor-infiltrating lymphocytes with enriched tumor-reactivity and specificity, wherein the 41BB agonist is present in the culture medium at day 0 of the culture. 
     
     
         2 . The method of  claim 1 , wherein the 41BB agonist comprises a recombinant human 4-1BB, or a fragment or variant thereof capable of ligating 41BB on T-cell. 
     
     
         3 . The method of  claim 1 , wherein the 41BB agonist comprises an agonistic anti-4-1BB antibody capable of ligating 41BB on T-cells to induce its co-stimulatory activity. 
     
     
         4 . The method of  claim 1 , wherein the culture medium further comprises a checkpoint inhibitor. 
     
     
         5 . The method of  claim 4 , wherein the checkpoint inhibitor comprises an anti-PD-1 antibody, anti-PD-L1 antibody, anti-CTLA-4 antibody, or a combination thereof. 
     
     
         6 . A method for treating a tumor in a subject comprising the steps of:
 a) expanding tumor-infiltrating lymphocytes from a tumor fragment from the subject using the method of  claim 1 ,   c) treating the subject with nonmyeloablative lymphodepleting chemotherapy, and   d) administering the tumor-infiltrating lymphocytes to the subject.   
     
     
         5 . The method of  claim 1 , wherein the cancer is a solid tumor. 
     
     
         6 . The method of  claim 1 , wherein the cancer is selected from the group consisting of melanoma, ovarian cancer, breast cancer, and colorectal cancer. 
     
     
         7 . The method of  claim 1 , wherein the cancer is metastatic. 
     
     
         8 . The method of  claim 1 , wherein the cancer is recurrent. 
     
     
         9 . The method of  claim 1 , wherein the subject is a human. 
     
     
         10 . The method of  claim 1 , wherein the culture medium is replaced with a new medium containing the 41BB agonist every two to three days. 
     
     
         11 . The method of  claim 3 , wherein the anti-4-1BB antibody is present in the medium at a concentration of about 0.5 to about 10 μg/ml. 
     
     
         12 . The method of  claim 3 , wherein the anti-4-1BB antibody is present in the medium at a concentration of about 10 μg/ml.