Progenitor cell preservation factors and methods for and products of their use

Abstract

Disclosed is the FRIL family of progenitor cell preservation factors and nucleic acids encoding the same. FRIL family members preserve progenitor cells both in vivo and ex vivo. FRIL family members find use as therapeutics for alleviating and/or reducing the hematopoietic progenitor cell-depleting activity of many cancer therapeutics. FRIL family members are also useful for isolating rare, primitive progenitor cells.

1 - 61 . (canceled)  
     
     
         62 . A method for alleviating or reducing the hematopoietic progenitor cell-depleting activity of a therapeutic treatment in a patient, comprising administering to the patient a therapeutically effective amount of a pharmaceutical composition prior to administration of the therapeutic treatment to the patient, wherein the pharmaceutical formulation comprises: 
 (a) a pharmaceutically acceptable carrier; and    (b) a protein that: 
 (1) binds to a normally glycosylated FLT3 receptor;  
 (2) has at least 95% amino acid sequence identity to an amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 6, and SEQ ID NO:8; and  
 (3) preserves hematopoietic progenitor cells.  
   
     
     
         63 . The method of  claim 62 , wherein the patient is human.  
     
     
         64 . The method of  claim 63 , wherein the patient has cancer.  
     
     
         65 . The method of  claim 62 , wherein the therapeutic treatment is selected from the group consisting of a radiotherapeutic, a chemotherapeutic, or a combination of a radiotherapeutic and a chemotherapeutic.  
     
     
         66 . The method of  claim 65 , wherein the chemotherapeutic is selected from the group consisting of cytarabine, doxorubicin, and 5-fluorouracil.  
     
     
         67 . The method of  claim 62 , wherein the protein is a recombinant protein.  
     
     
         68 . A method for preserving progenitor cells ex vivo, comprising contacting a population of cells comprising at least one progenitor cell with an effective amount of a pharmaceutical composition for an effective period of time, wherein the progenitor cells in the population are rendered quiescent, wherein the pharmaceutical formulation comprises: 
 (a) a pharmaceutically acceptable carrier; and    (b) a protein that: 
 (1) binds to a normally glycosylated FLT3 receptor;  
 (2) has at least 95% amino acid sequence identity to an amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 6, and SEQ ID NO:8; and  
 (3) preserves hematopoietic progenitor cells.  
   
     
     
         69 . The method of  claim 68 , wherein the progenitor cells are from a human.  
     
     
         70 . The method of  claim 68 , wherein the population of cells is bone marrow cells.  
     
     
         71 . The method of  claim 68 , wherein the non-progenitor cells in the population of cells differentiate or die.  
     
     
         72 . The method of  claim 68 , wherein the population of cells is removed from a cancer patient prior to treatment of the cancer patient with a therapeutic treatment having a hematopoietic progenitor cell-depleting activity.  
     
     
         73 . The method of  claim 72 , wherein the therapeutic treatment is selected from the group consisting of a radiotherapeutic, a chemotherapeutic, or a combination of a radiotherapeutic and a chemotherapeutic.  
     
     
         74 . The method of  claim 73 , wherein the chemotherapeutic is selected from the group consisting of cytarabine, doxorubicin, and 5-fluorouracil.  
     
     
         75 . The method of  claim 68 , wherein the protein is a recombinant protein.  
     
     
         76 . A method for preserving progenitor cells in vivo, comprising administering to a patient an effective amount of a pharmaceutical composition for an effective period of time, wherein the progenitor cells in the patient are rendered quiescent, wherein the pharmaceutical formulation comprises: 
 (a) a pharmaceutically acceptable carrier; and    (b) a protein that: 
 (1) binds to a normally glycosylated FLT3 receptor;  
 (2) has at least 95% amino acid sequence identity to an amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 6, and SEQ ID NO:8; and  
 (3) preserves hematopoietic progenitor cells.  
   
     
     
         77 . The method of  claim 76 , wherein the patient is human.  
     
     
         78 . The method of  claim 77 , wherein the patient is a cancer patient.  
     
     
         79 . The method of  claim 76 , wherein the effective amount of the pharmaceutical composition is administered prior to the treatment of the patient with a therapeutic treatment having a hematopoietic progenitor cell-depleting activity.  
     
     
         80 . A method for identifying a progenitor cell, comprising contacting a candidate cell with a FRIL family member molecule, wherein binding of the candidate cell to the FRIL family member molecule identifies the candidate cell as a progenitor cell, wherein the FRIL family member molecule comprises a protein that: 
 (1) binds to a normally glycosylated FLT3 receptor;    (2) has at least 95% amino acid sequence identity to an amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 6, and SEQ ID NO:8; and    (3) preserves hematopoietic progenitor cells.    
     
     
         81 . The method of  claim 80 , wherein the candidate cell is in a population of cells.  
     
     
         82 . The method of  claim 80 ,wherein the candidate cell is from a human.  
     
     
         83 . A progenitor cell identified by the method of  claim 80 .  
     
     
         84 . A method for identifying a member of the FRIL family of progenitor cell preservation factors, comprising contacting a candidate compound with a glycosylated extracellular domain of an FLT3 receptor, wherein the glycosylation pattern of the extracellular domain of the FLT3 receptor is the same as the glycosylation pattern of an extracellular domain of a normally glycosylated FLT3 receptor, wherein a candidate compound that binds the glycosylated extracellular domain of the FLT3 receptor is identified as a FRIL family member.  
     
     
         85 . The method of  claim 84 , wherein the candidate compound is a lectin.  
     
     
         86 . The method of  claim 85 , wherein the lectin is synthetic.  
     
     
         87 . The method of  claim 85 , wherein the lectin is from a legume.  
     
     
         88 . A method for isolating a population of progenitor cells, comprising contacting a population of cells with a plurality of FRIL family member molecules, and separating the unbound cells, wherein the cells bound to the FRIL family member molecules are an isolated population of progenitor cells, wherein the FRIL family member molecules comprise a protein that: 
 (1) binds to a normally glycosylated FLT3 receptor;    (2) has at least 95% amino acid sequence identity to an amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 6, and SEQ ID NO:8; and    (3) preserves hematopoietic progenitor cells.    
     
     
         89 . The method of  claim 88 , wherein the isolated population of progenitor cells is from a human.  
     
     
         90 . The method of  claim 88 , wherein the FRIL family member molecules are detectably labeled.  
     
     
         91 . The method of  claim 88 , wherein the FRIL family member molecules are immobilized on a solid support.  
     
     
         92 . The method of  claim 91 , wherein the solid support is a bead.  
     
     
         93 . The method of  claim 92 , wherein the bead is magnetic.  
     
     
         94 . The method of  claim 88 , wherein the unbound cells are separated by applying a magnet to the population of cells contacted with the FRIL family member molecules immobilized on the magnetic bead.  
     
     
         95 . The method of  claim 93 , wherein the population of cells bound to the FRIL family member molecules immobilized on a magnetic bead are rinsed with a physiologically acceptable solution while the magnet is applied.  
     
     
         96 . The method of  claim 91 , wherein the solid support is the bottom of a tissue culture plate.  
     
     
         97 . The method of  claim 88 , wherein the isolated population of progenitor cells is a population of hematopoietic progenitor cells.  
     
     
         98 . The method of  claim 88 , wherein the population of cells is selected from the group consisting of whole blood, umbilical cord blood, bone marrow cells, and fetal liver cells.  
     
     
         99 . The method of  claim 88 , wherein the population of cells is a sorted population of cells, wherein a cell of the sorted population does not express a cell surface molecule selected from the group consisting of CD11b, CD11c, and CD38.  
     
     
         100 . The method of  claim 99 , wherein the sorted population of cells is sorted by flow cytometry or by magnetic bead selection.  
     
     
         101 . An isolated population of progenitor cells isolated by the method of  claim 88 .  
     
     
         102 . The isolated population of progenitor cells of  claim 101 , wherein the isolated population of progenitor cells is from a human.  
     
     
         103 . The cells of  claim 101 , wherein the cells of the isolated population of progenitor cells do not express CD34.  
     
     
         104 . The cells of  claim 101 , wherein the cells of the isolated population of progenitor cells express a receptor tyrosine kinase selected from the group consisting of from FLK1, FLT1, FLT3, FLT4, and Kit.  
     
     
         105 . The cells of  claim 101 , wherein the cells of the isolated population of progenitor cells express a cell surface molecule selected from the group consisting of CD11b and CD11c.  
     
     
         106 . The isolated population of progenitor cells of  claim 101 , wherein the cells of the isolated population of progenitor cells express FLT3.  
     
     
         107 . The isolated population of progenitor cells of  claim 101 , wherein the cells of the isolated population of progenitor cells are selected from the group consisting of hemangioblasts, a messenchymal stem cells, bone progenitor cells, hepatic progenitor cells, endothelial progenitor cells, hematopoietic progenitor cells, embryonal stem cells, brain progenitor cell, and dendritic progenitor cells.  
     
     
         108 . The isolated population of progenitor cells of  claim 101 , wherein the cells of the isolated population of progenitor cells are hematopoietic progenitor cells.  
     
     
         109 . The isolated population of progenitor cells of  claim 101 , wherein transplantation of isolated population of progenitor cells into an animal lacking a population of hematopoietic progenitor cells sufficient to enable survival of the animal reconstitutes the animal, wherein the transplanted animal survives.