Drug – bio-affecting and body treating compositions – Antigen – epitope – or other immunospecific immunoeffector – Conjugate or complex
Reexamination Certificate
1998-10-05
2002-09-17
Bansal, Geetha P. (Department: 1642)
Drug, bio-affecting and body treating compositions
Antigen, epitope, or other immunospecific immunoeffector
Conjugate or complex
C435S007200, C435S007210, C435S007240, C435S325000, C435S354000, C435S366000, C435S355000, C435S372300, C435S373000, C435S384000, C530S350000
Reexamination Certificate
active
06451316
ABSTRACT:
TABLE OF CONTENTS
1. INTRODUCTION . . .
2. BACKGROUND OF THE INVENTION . . .
2.1 IMMUNITY AND IMMUNIZATION . . .
2.2 THE IMMUNE RESPONSE . . .
2.3 ADOPTIVE IMMUNOTHERAPY OF CANCER . . .
3. SUMMARY OF THE INVENTION . . .
4. BRIEF DESCRIPTIONS OF DRAWINGS . . .
5. DETAILED DESCRIPTION OF THE INVENTION . . .
5.1 SOURCES OF ANTIGENIC CELLS . . .
5.2 SOURCES OF IMMUNE CELLS . . .
5.2.1 IMMUNE CELLS PRIMED IN VIVO . . .
5.2.2 IMMUNE CELLS PRIMED IN VITRO . . .
5.3 GENERATION OF ANTIGEN-REACTIVE T CELLS . . .
5.4 PREPARATIONS OF HEAT SHOCK PROTEIN-ANTIGEN COMPLEXES . . .
5.4.1 PREPARATION AND PURIFICATION OF HSP 70 PEPTIDE COMPLEXES . . .
5.4.2 PREPARATION AND PURIFICATION OF HSP 90 PEPTIDE COMPLEXES . . .
5.4.3 PREPARATION AND PURIFICATION OF GP96 PEPTIDE COMPLEXES . . .
5.4.4 IN VITRO PRODUCTION OF HSP-ANTIGENIC MOLECULE COMPLEXES . . .
5.5 DETERMINATION OF REACTIVITY OF RESPONDING T CELLS . . .
5.6 REINFUSION OF ANTIGEN-REACTIVE T CELLS . . .
5.7 TARGET INFECTIOUS DISEASES . . .
5.8 TARGET CANCERS . . .
6. EXAMPLES . . .
6.1 MATERIALS . . .
6.2 CHARACTERIZATION OF ANTIGEN-REACTIVE T CELLS
6.3 ANTIGEN RECOGNITION BY CD4+ T CELLS . . .
1. INTRODUCTION
The present invention relates to methods for generating T cells reactive to an antigenic molecule (antigen-reactive T cells) for use in immunotherapy for the treatment and prevention of cancer and infectious diseases. The methods involve immunizing an animal and incubating the immune cells in vitro with a non-covalent complex of a heat shock protein (HSP) and an antigenic molecule. Methods for pulsing antigen presenting cells and/or immune cells with HSP-antigen complexes for the generation of CD4+ antigen-reactive T cells are provided. Methods and compositions are also provided for the treatment and prevention of cancer or infectious disease in a subject comprising administering to the subject antigen-reactive T cells that are expanded in vitro by the present methods.
2. BACKGROUND OF THE INVENTION
2.1 IMMUNITY AND IMMUNIZATION
The immune system protects a host against pathogens by mounting an immune response which is specific to an antigen of an invading pathogen. The objective of immunization is to elicit an early protective immune response by administering to the host an attenuated pathogen, or an antigen associated with a pathogen. This approach has been implemented successfully to prevent a variety of infectious diseases, such as polio, tetanus and diphtheria.
Immunization may be accomplished passively by administering either preformed immunoreactive serum or cells; or actively by presenting a suitable antigenic stimulus to the host's immune system.
Passive immunization is useful for a host who cannot produce antibodies, or for those who might develop disease before active immunization could stimulate antibody production. However, antibodies produced following some infections, particularly those due to mycobacteria, fungi, and many viruses, are not effective in protecting against the infection. Rather, the action of lymphocytes and macrophages largely determines recovery from these diseases.
Active immunization may be achieved with either viable or non-viable antigenic agents. Viable agents are generally preferred because the immune response provoked is more reliable and long-lived. However, viable vaccines may cause serious illness in an immunologically incompetent host, such as patients receiving corticosteroids, alkylating drugs, radiation or immunosuppressants. The use of attenuated strains always carries the risk that the attenuated agent may recombine with host DNA and mutate into a virulent strain. See generally, Ada, G. L., 1989, Chapter 36, in
Fundamental Immunology
, 2nd edition, ed. Paul W. E., Raven Press, New York, pp. 985-1032; Cohen, S. N., 1987, Chapter 37, in
Basic and Clinical Immunology
, 6th edition, ed. Stites, Stobo and Wells, Appleton and Lange, pp. 669-689.
2.2 THE IMMUNE RESPONSE
Cells of the immune system arise from pluripotent stem cells through two main lines of differentiation: a) the lymphoid lineage producing lymphocytes (T cells, B cells, natural killer cells), and b) the myeloid lineage (monocytes, macrophages and neutrophils, as well as accessory cells including dendritic cells, platelets and mast cells). In the circulatory system and secondary lymphoid organs of an adult animal, lymphocytes recirculate and search for invading foreign substances.
Pathogens and antigens tend to be trapped in secondary lymphoid organs, such as the spleen and the lymph nodes, where antigens are taken up or “captured” by antigen-presenting cells (APCs). The antigen presenting cells serve to display peptides and antigens to the immune cells by placing these peptides on the surface of the APC in association with a major histocompatibility complex (MHC) molecule. The process of antigen capture may occur by phagocytosis of exogenous proteins or by directed transport of proteins within the cell. Alternately, antigens may be derived from proteins synthesized within the cell. Next, antigens are processed into antigenic peptides by proteolytic degradation within the APC. The antigenic peptides are further complexed with a MHC molecule for presentation at the cell surface. Once an antigenic peptide is displayed by an MHC molecule on the antigen presenting cell (APC) surface, a cell-mediated immune reaction may follow which requires an interaction between the APC and a T cell. This interaction can trigger several effector pathways, including activation of T cells, and stimulation of T cell production of cytokines.
Interaction of an APC with a T cell is determined by several major components. These components include a) the T cell surface marker, b) the class of MHC molecule, and c) the T cell receptor (TCR).
T cells can be subdivided by their expression of surface markers CD4 and CD8. T cells expressing CD8 are often known as suppressor or cytotoxic cells. T cells expressing CD4 are often known as helper or inducer T cells. However, the CD8/CD4 dichotomy refers to the pattern of MHC association and antigen recognition. The CD8/CD4 nomenclature does not distinguish between cytotoxic and non-cytotoxic cells. The CD4 molecule binds to conserved structures of the class II MHC molecule. The CD8 molecule binds to conserved structures of class I MHC molecule.
The second factor important in APC/T cell interaction is the MHC. As indicated supra, the CD4 and CD8 molecules bind to the conserved structures of class II and class I MHC molecules, respectively. Class I and class II MHC molecules are the most polymorphic proteins known and play a major role in the immune system in the recognition of self and non-self. The heterogeneity of MHC molecule is observed at the level of haplotype or the combination of classes I and II MHC molecules encoded on a single chromosome. In the human, three distinct genetic loci designated, HLA-A, HLA-B and HLA-C, have been identified encoding class I molecules. Similarly, the three distinct loci encoding class II MHC molecules include HLA-DP, HLA-DR, and HLA-DQ. The multiple loci of MHC genes contribute to the complexity of self and non-self recognition process.
The third component important in APC/T cell interactions is the T-cell receptor (TCR). The TCR is responsible for the antigenic specificity of the T cell, and may only bind antigenic peptide that is associated with the polymorphic determinants of an MHC. Because the binding of the T-cell receptor is specific for a complex comprising an antigenic peptide and the polymorphic portion of the MHC molecule, T cells may not respond or respond poorly when an MHC molecule of a different genetic type is encountered. This specificity of binding results in the phenomenon of MHC-restricted T-cell recognition and T-cell cytotoxicity.
In pathogen-infected cells, proteins of the pathogens are degraded inside the cell. Some of the resulting peptides are transported into the lumen of the endoplasmic reticulum and may form complexes with class I MHC molecules. It has been previously shown that the pathogenic antigens can be chaperoned by heat shock p
Bansal Geetha P.
Pennie & Edmonds LLP
University of Conneticut Health Center
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