FIELD OF THE INVENTION
A process for the in vivo treatment of the bodily fluid of a biological organism wherein said organism is implanted with a device, the bodily fluid is brought into contact with a binding agent within the device and the velocity of at least one of the cellular components of the fluid is reduced.
DESCRIPTION OF RELATED ART
The prior art describes numerous processes detailing the isolation of desired biological targets from bodily fluids. As discussed in the prior art, a biological entity of interest typically is derived from a sample that is removed from a donor, which sample contains a heterogeneous mixture of cells and other biological substances. These substances span a size scale from the macroscopic to the molecular. The heterogeneous sample is subjected to one or more separation and purification procedures in order to obtain a preparation that is enriched with the biological target. Typical heterogeneous samples from which a biological target may be derived include: peripheral whole blood, bone marrow, tumor tissue, sputum, lymphatic fluid, ascites fluid, pleural fluid, spinal fluid, urine, gastro-intestinal fluid, bile, umbilical cord blood, amniotic fluid and so forth. Often, the amount of the biological entity of interest in the sample is negligible. Therefore, the target cell, stem cells, metastatic cancer cells, viruses, prion, and so forth, must be separated and purified from an overwhelming number of very similar, often nearly identical, non-target biological entities and other unwanted biological substances. Methods for separating and purifying cells and other biological entities have been developed. So-called positive separation methods take advantage of immunoaffinity-based technology. In an immunoaffinty-based method, antibody specific for a biological entity, for example a cell-type of interest, is linked to the surface of a solid such as a particle or filtration membrane. The captured cells, that is, cells bound to the solid through bonding to the antibody, are then separated from non-bound cells by filtration, adsorption on a column, partitioning in a magnetic field, centrifugation, and so on.
International application WO09944583 describes an implantable porous device used for isolating and/or stimulating the immune response within an individual that can also be used to sequester immune cells, which can later be introduced to the body. A primary embodiment of this invention is the implantation of a porous/permeable structure contained within an impermeable structure. The porous structure contains an antigen to initiate a humoral immune response. Diseased immune cells can also be sequestered within the device and caused to undergo apoptosis via specific cytokine initiation (p. 12, line 20). Immune cells may then be captured within the porous membrane, the device extracted and the cells later introduced within the body. It is disclosed that immune cells can be isolated and later used for various immunotherapy treatments (p.13-14).
A continuous-flow immunoaffinity method for separating target cells from non-target cells in whole blood withdrawn from a donor is described in U.S. Pat. No. 6,221,315. In this method target cells bind to dense, target cell specific particles that are then centrifuged and, thereby, the target cells are separated from non-bound cells.
A method for isolating metastatic cancer cells from donated blood is described in PCT Publication WO 0220825.
A capillary apparatus and associated immunoaffinity method for separating target cells from cells in a mixture is described in PCT Publication WO 0068689.
In PCT Publication WO 0162895, methods for concentrating and expanding T-cells are described, which methods depend upon binding of T-cells to co-stimulatory ligands attached to a surface. T-cells are derived from circulating blood obtained from an individual by apheresis or leukapheresis. In one embodiment of the disclosed methods, paramagnetic particles having attached ligands specific for the target cell surface moiety that induces cell stimulation are introduced into an animal. As stated in the PCT Publication, a magnetic field may be applied to a discrete region of the animal to induce localization and stimulation of the target cells bound to the particles at the discrete region.
Stem cells are cells capable of both indefinite proliferation and differentiation into specialized cells that serve as a continuous source for new cells for such tissues as blood, myocardium, liver, etc. Hematopoietic cells are rare, pluripotent cells, having the capacity to give rise to all lineages of blood cells. Stem cells undergo a transformation into progenitor cells, which are the precursors of several different blood cell types, including erythroblasts, myeloblasts, monocytes and macrophages. Stem cells have a wide range of potential applications, particularly in the autologous treatment of cancer patients.
Typically, stem cell products (true stem cells, progenitor cells and CD34+cells) are harvested from bone marrow of a donor in a procedure, which may be a painful, and requires hospitalization and general anesthesia. More recently, methods have been developed enabling stem cells and committed progenitor cells to be obtained from donated peripheral blood or peripheral blood collected during a surgical procedure.
Progenitor cells, whether from bone marrow or peripheral blood, can be used to enhance the healing of damaged tissues, such as myocardium damaged by myocardial infarction, as well as enhance hematologic recovery following an immunosuppressive procedure such as chemotherapy.
A number of immunotherapy strategies for treating cancer patients have been under development. These include (1) adoptive immunotherapy using different types of stimulated autologous cells, (2) systemic transfer of allogeneic lymphocytes, (3) vaccination at a distant site to generate a systemic tumor-specific immune response, and (4) implantation of immune cells directly into a tumor.
In adoptive immunotherapy, cells isolated from peripheral blood withdrawn from a patient are stimulated and then returned to the same patient; thus, the cells are histocompatible. The autologous lymphocytes may be stimulated ex-vivo with tumor-associated antigen to make them tumor-specific (Zarling et al. (1978) Nature 274:269-71 and U.S. Pat. No. 5,192,537) or autologous lymphocytes and killer cells can be stimulated non-specifically as described in U.S. Pat. No. 5,308,626. The entire disclosure of each of these United States patents is hereby incorporated by reference into this specification.
Peripheral blood-derived lymphocytes cultured in the presence of interleukin-2 form lymphokine-activated killer (LAK) cells, which have been used to treat individuals suffering from metastatic melanoma and renal cell carcinoma (Rosenberg (1987) New Engl. J. Med. 316:889-897). LAK cells have also been used to treat brain tumors (Merchant et al. (1988) Cancer 62:665-671 and (1990) J. Neuro. Oncol. 8:173-198).
Another form of adoptive immunotherapy involves the use of autologous tumor-infiltrating lymphocytes (TIL) (Rosenberg et al. (1990) New Engl. J. Med. 323:570-578). Unfortunately, a clinically useful quantity of TILs from a donor can only be obtained and prepared in a limited number of tumor types.
In adoptive transfer of allogeneic lymphocytes, lymphocytes obtained from a donor are used to induce a general level of immune stimulation against tumors (Strausser et al.(1981) J. Immunol. Vol. 127, No. 1, Zarling et al.(1978) Nature 274:269-71 and Kondo et al. (1984) Med Hypotheses 15:241-77).
The third immunotherapy strategy listed above, involves generating an active systemic tumor-specific immune response of host origin by administering a vaccine composition (tumor-antigen vaccines and anti-idiotype vaccines) at a site distant from the tumor.
Another approach involves using tumor cells derived from a donor to be treated (Schirrmacher et al. (1995) J. Cancer Res. Clin. Oncol. 121:487-489 and U.S. Pat. No. 5,484,596).
Autologous tumor cells have been used in combination with allogeneic cytokine-secreting cells in treating cancers, as described in PCT Publication WO 98/16238.
The fourth immunotherapy strategy listed above, intra-tumor implantation, involves delivering effector cells in proximity to a tumor site. Different effector-cell types (syngeneic lymphocytes, non-adherent LAK cells, adherent LAK cells, syngeneic cytotoxic T lymphocytes (CTL) raised against tumor antigens, and allogeneic CTL raised against alloantigens) have shown success in a rat gliosarcoma cell line (Kruse et al. (1990) Proc. Natl. Sci. USA, 87:9377-9381).
The T-cell antigen receptor (TCR) is a multisubunit immune recognition receptor that associates with the CD3 complex and binds to peptides presented by the major histocompatibility complex (MHC) class I and 11 proteins on the surface of antigen-presenting cells (APCs). Binding of TCR to the antigenic peptide on the APC is the central event in T-cell activation. A requirement for MHC-matched APCs as accessory cells for T-cell stimulation is problematic because APCs are relatively short-lived and, therefore, in a long-term culture system they must be continually obtained from a donor and replenished.
The isolation and use of dendritic cells from donated human peripheral blood in immunotherapy methods for treating prostate cancer is described in U.S. Pat. No. 5,788,963.
The use of hematopoietic and cardiac stem cells for regenerating damaged myocardium is described in PCT Publication WO 209650.
The use of human umbilical blood as a source of neural cells for transplantation is described in PCT Publication WO 0166698.
Clearly, a need exists for providing many different endogenous cell-types, infected or uninfected, from human and non-human donors for use in numerous and varied human and veterinary research, diagnostic and therapeutic applications. Endogenous cells from a donor, in general, may be used for genetic screening purposes in birth disorders or in organ replacement therapy.
A need exists for capturing circulating cells, such as cancer cells with the potential to metastasize, viruses, bacteria, prions and other biological entities. This need encompasses research, diagnostics and therapeutics applications in diverse disciplines including, genetics, hematology, microcirculation, oncology, infectious disease, immunology and microbiology.
There exists a need for obtaining cellular samples from donors that are enriched in the desired biological target. Because a heterogeneous sample contains a negligible amount of a biological entity of interest, the limits of separation methods to provide viable and potent biological target in sufficient purity and amount for research, diagnostic or therapeutic use are often exceeded. Because of the low yield after separation and purification, some cell-types, such as stem cells, progenitor cells and immune cells (particularly T-cells) must be placed in long-term culture systems under conditions that enable cell viability and clinical potency to be maintained and under which cells can propagate (cell expansion). Such conditions are not always known. In order to obtain a sufficient amount of a biological target, a large amount of a sample, such as peripheral blood, must be obtained from a donor at one time, or samples must be withdrawn multiple times from a donor and then subjected to one or more lengthy, expensive, and often low-yield separation procedures to obtain a useful preparation of the biological target. Taken together, these problems place significant burdens on donors, separation methods, laboratory personnel, clinicians and patients. These burdens significantly add to the time and costs required to isolate the desired cells.
There exists a need for obtaining cells from non-humans, which cells comprise particular antigens or antibodies of interest. The transcription and translation levels of any number of constituents, mechanical properties, in vitro memory properties or genetic properties of cells can be analyzed. Capturing immune cells, stem cells and committed progenitor cells, and metastatic cancer cells, blood borne viruses are of particular interest.
There exists a need for devitalizing circulating cells to minimize their potential to induce or promote disease in the host.
It is an object of this invention to provide a sample directly from a donor, which sample is enriched or sufficiently enriched with biological target.
It is an object of this invention to provide an implantable target specific capture device that enables easy and repeated access in order to obtain samples when desired, without requiring removal of the device from a donor, which samples are enriched with the target of interest.
It is an object of this invention to provide a capture device that could be configured to simultaneously capture multiple targets (e.g. multiple types of metastatic cancer cells).
It is an object of this invention to provide a capture device that could be easily modified to enable it to capture different types of cells.
It is an object of this invention to provide a capture device that could capture, sequester, and maintain the viability of the captured cells until the cells are harvested.
It is an object of this invention to provide a capture device that could devitalize (i.e. destroy) the captured cells, such as metastatic cancer cells or HIV-infected cells, particularly without the need for additional interactions from the host.
These and other objects afforded by the methods and implantable target specific capture devices of the invention will become evident upon consideration of the following drawings, summary and detailed description.
BRIEF SUMMARY OF THE INVENTION
In accordance with one embodiment of the invention, there is provided a process for treating biological targets within the fluid of an organism comprising the steps of (1) feeding the fluid into a chamber which is comprised of a target specific binding agent, (2) modifying the flow dynamics of the fluid, and (3) allowing the biological target to bind with the target specific binding agent.
DEFINITION OF TERMS
As described herein, several terms are given specific meaning within the context of this writing. These terms are hereby defined as follows:
As described herein, the term “in-vivo device” refers to a device that attaches to fluid flow systems within the body, such as a vein or an artery. Portions of the device may be located outside the body and connected to the internal flow system by connections through the skin.
The term “biological target” refers to any endogenous infected or uninfected cell, or similar biological particles, including metastatic cancer cells and HIV infected cells, or virus, or bacterium, or prion, or other biological entity of interest that may be present in a fluid of a human or non-human donor. Endogenous cells include but are not limited to, subsets of cells within a defined cell family, for example a B-lymphocyte or a T-lymphocyte in the lymphocyte family, or a cytolytic T-lymphocyte in the T-lymphocyte family, or an entire family of cells, such as the lymphocyte family. Examples of other endogenous cells are fibroblasts, neuroblasts, hematopoietic stem cells, hematopoietic progenitor cells (CD34+cells), mesenchymal stem cells, dendritic cells, cytolytic T-cells (CD8+cells), other leukocyte populations, pluripotent stem cells, multi-potent stem cells, embryonic cells or islet cells. Biological targets include populations of cells having distinct phenotypic characteristics: B-cells, T-cells, NK cells, other blood cells, neuronal cells, glandular (endocrine) cells, bone forming cells (osteoclasts, etc.), germ cells (e.g., oocytes), epithelial cells lining reproductive organs, trophoblastic and placental cells in amniotic fluid and mesenchymal progenitor, neuronal progenitor, neuroectodermal cells. A biological target such as a leukocyte, stem cell or an insoluble protein may be in suspension within a fluid of a donor or it may be dispersed as a microscopic colloid, such as a large soluble protein or it may be in true molecular solution, such as a small molecule.
The term “target specific binding agent” refers to a molecule or fragment of a molecule that binds to a particular biological target. A target specific binding agent may bind a cell surface moiety, such as a receptor, an antigenic determinant, an integrin, a cell adhesion molecule, or other moiety present on a cell-type of interest. A binding agent may be specific for a region of a protein, such as a prion, a capsid protein of a virus or some other viral protein, and so on. A target specific binding agent may be a protein, peptide, antibody, antibody fragment, a fusion protein, synthetic molecule, an organic molecule (e.g., a small molecule), or the like. In general, a target specific binding agent and its biological target refer to a ligand/anti-ligand pair. Accordingly, these molecules should be viewed as a complementary/anti-complementary set of molecules that demonstrate specific binding, generally of relatively high affinity. Cell surface moiety-ligand pairs include, but are not limited to, T-cell antigen receptor (TCR) and anti-CD3 mono or polyclonal antibody, TCR and major histocompatibility complex (MHC)+antigen, TCR and super antigens (for example, staphylococcal enterotoxin B (SEB), toxic shock syndrome toxin (TSST), etc.), B-cell antigen receptor (BCR) and anti-immunoglobulin, BCR and LPS, BCR and specific antigens (univalent or polyvalent), NK receptor and anti-NK receptor antibodies, FAS (CD95) receptor and FAS ligand, FAS receptor and anti-FAS antibodies, CD54 and anti-CD54 antibodies, CD2 and anti-CD2 antibodies, CD2 and LFA-3 (lymphocyte function related antigen-3), cytokine receptors and their respective cytokines, cytokine receptors and anti-cytokine receptor antibodies, TNF-R (tumor necrosis factor-receptor) family members and antibodies directed against them, TNF-R family members and their respective ligands, adhesion/homing receptors and their ligands, adhesion/homing receptors and antibodies against them, oocyte or fertilized oocyte receptors and their ligands, oocyte or fertilized oocyte receptors and antibodies against them, receptors on the endometrial lining of uterus and their ligands, hormone receptors and their respective hormone, hormone receptors and antibodies directed against them, and others. Other examples may be found by reference to U.S. Pat. No. 6,265,229; U.S. Pat. No. 6,306,575 and WO 9937751.
The term “enriched” means that the amount of biological target contained in a unit volume of donor fluid from which it is derived is less than the amount contained after release from an implanted target specific capture device or multiple devices and reconstitution into an identical volume of suitable liquid medium. The term “sufficiently enriched” means there is a sufficient amount of biological target within an implanted device or multiple devices such that the biological target may be used directly in a research, diagnostic or therapeutic application for which it is intended, or there is a sufficient amount of biological target so as to significantly reduce the amount of sample required to obtain a useful preparation using conventional separation and purification methods such as those noted earlier.
The term “bio-active agent” includes, for example, cytokines or any substance that may either induce or reduce cell viability or potency. A bio-active agent may be a peptide, a nucleic acid, a protein, a small organic molecule, an antithrombogenic agent, an antibiotic, an antibacterial agent, an antiviral agent, a heparin, a prostaglandin, urokinase, streptokinase, a polysaccharide, a sulfated polysaccharide, an albumin, a pharmaceutical agent, a growth factor, an antibody, an adhesion factor, an integrin, or any combination, derivative or modification thereof.
The term “fluid communication” means that two objects A and B are related such that a pathway, conduit, channel or passageway exists between objects A and B enabling a volume element of fluid at a locus of A to flow, move, pass, be conducted or transported, along the pathway, conduit, channel or passageway to a locus b of object B. The pathway, conduit, channel or passageway may be linear, non-linear, convoluted, or be of any form as long as a volume element of fluid can pass from object A to object B.
The term “capture zone” refers to any region or locus of an implantable device that comprises target specific binding agent immobilized thereto or therein. If the construction of a capture zone is such that it forms a volume element, the volume element may comprise any natural or synthetic polymer, fiber, diatomaceous earth, glass, metal, colloid, or plastic, and so on, or any combination thereof that may or may not be biodegradable or that may be biodegradable in one embodiment and non- biodegradable in another embodiment or vice versa. The natural or synthetic polymer, fiber, diatomaceous earth, glass, metal, colloid, or plastic, and so on, may be integral with the material substance that forms the capture zone or it may not be integral with it. The natural or synthetic polymer, fiber, diatomaceous earth, glass, metal, colloid, or plastic, and so on, may be particulate, such as in the form of spherical or substantially spherical beads. It may be laminar, in the form of multiple sheets, corrugated, smooth, fibrous, fiber bundles, porous, or of uniform or non-uniform shape and size, or any combination thereof. Biological target specific binding agent, and/or bio-active agent may be immobilized directly to the material substance forming a capture zone or a material substance on a surface or within a volume element of the capture zone.
The term “immobilized”, within the context of the present invention, means rigidly or substantially localized at a site, region or locus by way of covalent or non-covalent bonding or encapsulation. Numerous methods and materials for immobilizing molecules to substrates are well known to skilled artisans. For example, see: U.S. Pat. No. 4,980,299; U.S. Pat. No. 4,284,553; U.S. Pat. No. 6,365,418; U.S. Pat. No. 5,399,501 and U.S. patent application Ser. No. 2001 0044655. Encapsulation of biological substances is also well known to skilled artisans and is well documented. For example, see: U.S. Pat. No. 5,227,298; U.S. Pat. No. 5,053,332; U.S. Pat. No. 4,997,443; U.S. Pat. No. 4,971,833; U.S. Pat. No. 4,902,295; U.S. Pat. No. 4,798,786; U.S. Pat. No. 4,673,566; U.S. Pat. No. 4,647,536; U.S. Pat. No. 4,409,331; U.S. Pat. No. 4,392,909; U.S. Pat. No. 4,352,883; U.S. Pat. No. 4,663,286; and U.S. Pat. No. 5,643,569.
The term “chemical attractant” or “chemoattractant” means a substance capable of luring a biological target that is capable of migration to the capture zone. One or more chemical attractants may be included in a target specific capture device. Reference may be had, e.g., U.S. Pat. No. 6,419,917; U.S. Pat. No. 6,274,342; U.S. Pat. No. 6,458,349; U.S. Pat. No. 6,320,023; and U.S. Pat. No. 6,207,144.
The term “bio-compatible” means not toxic or not known to be toxic to a living being.
The term “implantable device” refers to any article that may be used within the context of the methods of the invention for changing the concentration of a cell of interest in vivo. An implantable biological target capture device may be, inter alia, a stent, catheter, cannula, capsule, patch, wire, infusion sleeve, fiber, shunt, graft, and so on. An implantable biological target specific capture device and each component part thereof may be of any bio-compatible material composition, geometric form or construction as long as it is capable of being used according to the methods of the invention. The literature is replete with publications that teach materials and methods for constructing implantable devices and methods for implanting such devices, including: U.S. Pat. No. 5,324,518; U.S. Pat. No. 5,976,780; U.S. Pat. No. 5,980,889; U.S. Pat. No. 6,165,225; U.S. Patent Publication 2001 0000802; U.S. Patent Publication 2001 0001817; U.S. Patent Publication 2001 0010022; U.S. Patent Publication 2001 0044655; U.S. Patent Publication 2001 0051834; U.S. Patent Publication 2002 0022860; U.S. Patent Publication 2002 0032414; EP 0809523; EP 1174156; EP 1101457; WO 9504521.
The term “anti-thrombogenic” or “anticoagulant” means the ability to counteract the tendency for an organism's blood to clot or coagulate, called thrombosis.
The term “devitalizing” refers to the ability of a substance to kill or incapacitate a cell such that it is no longer capable of acting in a functional capacity. A “devitalized” cell is unable to function in the same manner it did before devitalization. For example, a metastatic cancer cell could be devitalized not only by killing the cell via lysis, necrosis, or programmed cell death, but could be made to be no longer able to divide. Similarly, an immune cell, such as an activated T cell, may not only be killed via lysis, necrosis, or programmed cell death, but may be forced to no longer be activated.
The term “activating” refers to the ability of a bio-active agent to impart additional functionality to a biological target. The functionality is not expressed by the biological target until after it has been acted upon by the bio-active agent. By way of illustration, T cells may be activated.
The term “differentiate” refers to the process of causing one cell type to change into another cell type. For example, a stem cell may differentiate into a specialized cell type.
The term “morphological characteristic” refers to the properties of a biological target that gives rise to its function. For example, changing the morphological characteristics of a biological target means to change its properties such that it is devitalized, activated, or differentiated.
“Cell holding binding” means binding of a biological target such that the target is no longer able to leave a capture zone. The duration of the binding may be temporary or it may be permanent.
The term “margination” refers to the migration of a biological target from a position in its carrier fluid to the wall of the channel that carries the fluid. The concentration of marginated biological targets will be enriched near the walls of the channel. An agent is deemed to be margined when its translational velocity is below the critical hydrodynamic velocity (Vcrit) at a radial position one cell radius from the channel wall. The critical hydrodynamic velocity for a given tube may be calculated from the Navier-Stokes equation:
Vcrit=(2Q/D2)ε(2−ε) where ε=Dcell/Dchannel. One means for measuring the translation velocity of an agent is taught elsewhere in this specification.
The term “flow dynamics” refers to the wall shear rate, the flow rate, and the translational velocity of a specified particle within a moving fluid. To modify the flow dynamics, at least one of the aforementioned properties must be altered.