Methods of using mutant flt3-ligand polypeptides to induce cellular expansion
AssigneeImmunex Corporation
InventorsThomas J. Graddis, Jeffrey T. McGrew
Life of this patent
Estimating the term…
Abstract
A screening method for identifying mutant polypeptides having at least one amino acid difference from a wild type protein involved in a receptor-ligand interaction is disclosed. Also disclosed are mutant polypeptides of the hematopoietic growth factor flt3-Ligand (flt3-L) identified using this method, nucleic acids encoding these flt3-L mutant polypeptides, and methods of treatment involving in vitro and in vivo use of the mutant polypeptides and nucleic acids.
Claims54
A method of inducing cellular expansion, comprising the steps of:
- isolating a population of cells to be expanded;
- and
- exposing said cells to a soluble mutant flt3-L polypeptide to produce an expanded cell population, wherein said polypeptide comprises a substitution at one or more residues corresponding to amino acid position 24 of the full length human wild type flt3-L polypeptide (SEQ ID NO:1) or amino acid positions 8–15, 81–87 or 116–124 of the mature human wild type flt3-L polypeptide (SEQ ID NO:18), wherein the mutant flt3-L polypeptide exhibits increased biological activity relative to full length wild type (SEQ ID NO:1) or mature human wild type (SEQ ID NO:18) flt3-L polypeptide.
A method of expanding a population of cells in vivo, comprising the step of administering to a subject a pharmaceutical composition of a soluble mutant flt3-L polypeptide sufficient to induce the expansion of a target cell population, wherein said polypeptide comprises a substitution at one or more residues corresponding to amino acid position 24 of the full length human wild type flt3-L polypeptide (SEQ ID NO:1) or amino acid positions 8–15, 81–87 or 116–124 of the mature human wild type flt3-L polypeptide (SEQ ID NO:18), wherein the mutant flt3-L polypeptide exhibits increased biological activity relative to full length wild type (SEQ ID NO:1) or mature human wild type (SEQ ID NO:18) flt3-L polypeptide.
A method for transplanting hematopoietic stem cells, progenitor cells or both hematopoietic stem cells and progenitor cells in a patient in need thereof, comprising:
- (a) administering a therapeutically effective amount of a pharmaceutical composition comprising a soluble flt3-L mutant polypeptide to the patient to expand the hematopoietic stem cells, progenitor cells or both in the patient, wherein said polypeptide has a substitution at one or more residues corresponding to amino acid position 24 of the full length human wild type flt3-L polypeptide (SEQ ID NO:1) or amino acid positions 8–15, 81–87 or 116–124 of the mature human wild type flt3-L polypeptide (SEQ ID NO:18) wherein the mutant flt3-L polypeptide exhibits increased biological activity relative to full length wild type (SEQ ID NO:1) or mature human wild type (SEQ ID NO:18) flt3-L polypeptide;
- (b) collecting said expanded hematopoietic stem cells, progenitor cells or both from the patient;
- and
- (c) transplanting said cells collected in step (b) to the patient.
A method for transplanting hematopoietic stem cells, progenitor cells or both hematopoietic stem cells and progenitor cells in a patient in need thereof, comprising:
- (a) collecting hematopoietic cells, progenitor cells or both from the patient;
- (b) administering ex vivo an effective amount of a composition comprising a soluble flt3-L mutant polypeptide to said cells collected in step (a) to expand the hematopoietic stem cells, progenitor cells or both, wherein said polypeptide has a substitution at one or more residues corresponding to amino acid position 24 of the full length human wild type flt3-L polypeptide (SEQ ID NO:1) or amino acid positions 8–15, 81–87 or 116–124 of the mature human wild type flt3-L polypeptide (SEQ ID NO:18) wherein the mutant flt3-L polypeptide exhibits increased biological activity relative to full length wild type (SEQ ID NO:1) or mature human wild type (SEQ ID NO:18) flt3-L polypeptide;
- and
- (c) transplanting said expanded hematopoietic stem cells, progenitor cells or both to the patient.
Dependencies are inferred from the claim text.