Cell Therapy


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Related to Cell Therapy: cell theory, Stem cell therapy

Cell therapy

 

Definition


Cell therapy is the transplantation of human or animal cells to replace or repair damaged tissue.

Purpose


The purpose of cell therapy is to introduce cells into the body that will grow and replace damaged tissue. Cell therapy differs from conventional stem cell therapy in that the cells injected into the body in cell therapy are already differentiated (e.g., muscle cells, gland cells), whereas conventional stem cell therapy utilizes undifferentiated, usually embryonic cells. Cell therapy has long been used by alternative medicine practitioners who have claimed great benefits; these have not been replicated by conventional medical practitioners.

Description


The theory behind cell therapy has been in existence for several hundred years. The first recorded discussion of the concept of cell therapy can be traced to Phillippus Aureolus Paracelsus (1493-1541), a German-Swiss physician and alchemist who wrote in his Der grossen Wundartzney (Great Surgery Book) in 1536 that "the heart heals the heart, lung heals the lung, spleen heals the spleen; like cures like." Paracelsus and many of his contemporaries agreed that the best way to treat an illness was to use living tissue to restore the ailing. In 1667, at a laboratory in the palace of Louis XIV, Jean-Baptiste Denis (1640-1704) attempted to transfuse blood from a calf into a mentally ill patient. Since blood transfusion is, in effect, a form of cell therapy, this could be the first documented case of this procedure. However, the first recorded attempt at non-blood cellular therapy occurred in 1912 when German physicians attempted to treat children with hypothyroidism (underactive thyroid gland), with thyroid cells.
In 1931, Dr. Paul Niehans (1882-1971), a Swiss physician, became known as "the father of cell therapy" quite by chance. After a surgical accident by a colleague, Niehans attempted to replace a patient's severely damaged parathyroid glands with those of a steer. When the patient began to rapidly deteriorate before the transplant could take place, Niehans decided to dice the steer's parathyroid gland into fine pieces, mix the pieces in a saline solution, and inject them into the dying patient. He reported that immediately the patient began to improve and, in fact, lived for another 30 years.

Cell therapy as alternative medicine


Cell therapy as performed by alternative medicine practitioners is very different from the controlled research done by conventional stem cell medical researchers. Alternative practitioners refer to their form of cell therapy by several other different names including xenotransplant therapy, glandular therapy, and fresh cell therapy. The procedure involves the injection of either whole fetal xenogenic (animal) cells (e.g., from sheep, cows, pigs, and sharks) or cell extracts from human tissue. Several different types of cells may be administered simultaneously.
Just as Paracelsus's theory of "like cures like," the types of cells that are administered correspond in some way with the organ or tissue in the patient that is failing. In other words, the cells are not species specific, but only organ specific. Alternative practitioners cannot explain how this type of cell therapy works, but proponents claim that the injected cells travel to the similar organ from which they were taken to revitalize and stimulate that organ's function and regenerate its cellular structure. Supporters of cellular treatment believe that embryonic and fetal animal tissue contain active therapeutic agents distinct from vitamins, minerals, hormones, or enzymes. This theory and these claims are rejected by practitioners of conventional medicine.
Proponents of cell therapy claim that it has been used successfully to rebuild damaged cartilage in joints, repair spinal cord injuries, strengthen a weakened immune system, treat autoimmune diseases such as AIDS, and help patients with neurological disorders such as Alzheimer's disease, Parkinson's disease, and epilepsy. Further claims of positive results have been made in the treatment of a wide range of chronic conditions such as arteriosclerosis, congenital defects, and sexual dysfunction. The therapy has also been used to treat cancer patients at a number of clinics in Tijuana, Mexico. Most of these claims are anecdotal. None of these application is supported by well-designed, controlled clinical studies.

Key Terms

Cell therapy as conventional medicine


Cell therapy in conventional medicine is still in the research and early clinical trial stage. This research is an outgrowth of stem cell research, and is performed in government-regulated laboratories by traditionally trained scientists. Embryonic stem cells are cells taken from an embryo before they have differentiated (specialized) into such specific cell types as muscle cells, nerve cells, or skin cells. In laboratory test tube and animal experiments, stem cells often can be manipulated into differentiating into specific types cells that have the potential to replace differentiated cells in damaged organs. For example, in early 2008, researchers at the Diabetic Research Institute at the University of Miami in Florida were able to convert embryonic stem cells into insulin-producing cells and use them to treat insulin-dependent diabetes in mice.
Stem cells also have been found in bone marrow, and work is underway to see if other cells can be manipulated into transforming into differentiated cells. In January 2009, researchers at Northwestern University's Feinberg School of Medicine in Chicago announced that they had used a patient's own bone marrow stem cells to improve early symptoms of multiple sclerosis. Researchers noted improvement only in patients with early symptoms; in earlier research those with advanced symptoms had not improved. Other researchers are working on treating symptoms of muscular dystrophy with fully differentiated myoblasts (a kind of muscle cell) with mixed results. Still other are working with using cartilage cells (chondrocyte cells) to repair cartilage in joints such as the knee.
Stem cell therapy has potential to treat a wide range of diseases and disorders, but it is, for the most part, still in the test tube and animal research stage of development. Because of the ethical questions raised when the harvesting of stem cells destroys embryos, the United States has placed restrictions on some human stem cell research. These restrictions, however, do not apply to research that does not destroy embryos. However, much stem cell research is being carried out in other countries, especially Thailand, South Korea, and China, where fewer restrictions are placed on obtaining human stem cells for experimentation. A list of FDA-approved clinical trials involving stem cell therapy can be found at http://www.clinicaltrials.gov.

Preparations


Alternative practitioners use several processes to prepare cells for use. One procedure involves extracting cells from the patient and then culturing them in a laboratory until they multiply to the level needed for transplantation back into the same patient. Another procedure uses freshly removed fetal animal tissue that has been processed and suspended in a saline (salt water) solution. The preparation of fresh cells then may be either injected immediately into the patient or preserved by being freeze-dried or deep-frozen in liquid nitrogen before being injected. Injected cells may or may not be tested for pathogens, such as bacteria, viruses, or parasites, before use. Conventional cell therapy researchers work in laboratories where the growing environment of the cells is highly controlled and monitored to prevent contamination.

Precautions


Many forms of cell therapy in the United States are highly experimental procedures. Patients should approach any cell therapy treatments with extreme caution, inquire about their proven efficacy and legal use in the United States or their home country, and should only accept treatment only from a licensed physician who should educate the patient completely on the risks and possible side effects involved with cell therapy. These same cautions apply for patients interested in participating in FDA-approved clinical trials of cell therapy treatments.

Side effects


Because cell therapy encompasses a wide range of treatments and applications and many of these treatments are unproven and highly experimental, the full range of possible side effects of the treatments is not yet known. Anaphylactic shock, immune system reactions, and encephalitis are just a few of the known reported side effects in some patients to date.
Patients undergoing cell therapy treatments which use cells transplanted from animals or other humans run the risk of cell rejection, in which the body recognizes the cells as a foreign substance and uses immune system cells to attack and destroy them. Some forms of cell therapy use special coatings on the cells in an attempt to trick the immune system into recognizing the new cells as native to the body. There is also the chance of the cell solution transmitting a bacterial, viral, fungal, or parasitic infection to the patient. Careful screening and testing of cells for pathogens can reduce this risk.

Research and general acceptance


Cell therapy as alternative healers practice it is generally rejected as effective by the traditionally-trained scientific community. Most of the claims made for these therapies are based on anecdotal evidence and are not backed by controlled clinical trials. While some mainstream cell therapy procedures have shown some success in clinical studies, others are still largely unproven, including cell therapy for cancer treatment. Until large, controlled human clinical studies are performed on cell therapy procedures, they will remain fringe treatments.

For Your Information

Resources


Books

  • Steenblock, David and Anthony G. Payne.Umbilical Cord Stem Cell Therapy: The Gift of Healing from Healthy Newborns. Laguna Beach, CA: Basic Health Publications, 2006.

Periodicals

  • Pollack, Andrew. "Stem Cell Therapy Controls Diabetes in Mice." New York Times. February 21, 2007 [cited February 2, 2009] http://www.nytimes.com/2008/02/21/health/research/21stem.html.

Websites

  • "Cellular Therapy." Quackwatch. 2003 [cited February 2, 2009]. http://www.quackwatch.com/01QuackeryRelatedTopics/Cancer/cellular.html.

  • " Multiple Sclerosis 'Reversed' with Stem Cell Therapy." New Scientist Health. January 30, 2009 [cited February 2, 2009]. http://www.newscientist.com/article/dn16509-multiple-sclerosis-reversed-with-stem-cell-therapy.html.

Organizations

  • Alternative Medicine Foundation. P. O. Box 60016, Potomac, MD 20859. (301) 340-1960. http://www.amfoundation.org.

  • Center for Cell and Gene Therapy. Baylor College of Medicine. One Baylor Place N1002, Houston, TX 77030 (713) 798-1246. http://www.bcm.edu/genetherapy.

Cell therapy
Alternative-Fringe medicine
(1) Live cell therapy
(2) The injection of cellular material from organs, foetuses, or embryos of animals to stimulate healing, counteract the effects of ageing, and treat a variety of degenerative diseases such as arthritis, Parkinson’s disease, atherosclerosis, and cancer; methods include the use of live cells, freeze-dried cells, cells from specific organs, and whole embryo preparations
Molecular medicine
(1) Gene therapy, see there
(2) Stem cell therapy
Quackery Sicca cell treatment

cell

1. the basic structural unit of living organisms.
2. a small more or less enclosed space.
All living cells arise from other cells, either by division of one cell to make two, as in mitosis and meiosis, or by fusion of two cells to make one, as in the union of the sperm and ovum to make the zygote in sexual reproduction.
All cells are bounded by a structure called the cell membrane or plasma membrane, which is a lipid bilayer composed of two layers of phospholipids. Each layer is one molecule thick with the charged, hydrophilic end of the lipid molecules on the surface of the membrane and the uncharged hydrophobic fatty acid tails in the interior of the membrane.
Cells are divided into two classes, eukaryotic cells and prokaryotic cells:
Eukaryotic cells have a true nucleus, which contains the genetic material, composed of the chromosomes, each of which is a long linear deoxyribonucleic acid (DNA) molecule associated with protein. The nucleus is bounded by a nuclear membrane, which is composed of two lipid bilayer membranes.
Prokaryotic cells, the bacteria, have no nucleus, and their genetic material, consisting of a single circular naked DNA molecule, is not separated from the rest of the cell by a nuclear membrane.
Eukaryotic cells are larger and more complex than prokaryotic cells. They also have membrane-bounded structures, such as mitochondria, chloroplasts, Golgi apparatus, endoplasmic reticulum and lysosomes, that prokaryotic cells lack.
The contents of a cell are referred to collectively as the protoplasm. In eukaryotic cells the contents of the nucleus are referred to as nucleoplasm and the rest of the protoplasm as the cytoplasm.
The lipid bilayer of eukaryotic cells is impermeable to many substances, such as ions, sugars and amino acids; however, membrane proteins selectively move specific substances through the cell membrane by active or passive transport. Water, gases such as oxygen and carbon dioxide, and nonpolar compounds pass through the cell membrane by diffusion. Materials can also be engulfed and taken into the cell enclosed in a portion of the cell membrane. This is called phagocytosis when solids are ingested and pinocytosis when liquids are ingested. The reverse process is called exocytosis. All of these processes permit the cell to maintain an internal environment different from its exterior. See also body fluids.
The cells of the body differentiate during development into many specialized types with specific tasks to perform. Cells are organized into tissues and tissues into organs. Embedded in the cell membrane are a wide range of molecules that vary with the cell type and are typically composed of proteins or glycoproteins that have a cytoplasmic transmembrane and external domains. These molecules serve as cell receptors and are involved in signal transduction for a wide range of ligands, including hormones, cytokines and incidentally serve as receptors for viruses and drugs.
See also betz cells, gaucher's cells, golgi's cells, hela cells, hürthle cell, kupffer's cells, merkel cell, mesangial cell, neuroendocrine cell.
Enlarge picture
Structure of the cell as seen by light microscopy. By permission from Guyton R, Hall JE, Textbook of Medical Physiology, Saunders, 2000

accessory c's
macrophages involved in the processing and presentation of antigens making them immunogenic.
acinar cell, acinous cell
any of the cells lining an acinus, especially applied to the zymogen-secreting cells of the pancreatic acini.
adherent cell
one that adheres to the glass or plastic container in cell cultures, to form the monolayer. See also cell culture.
alpha c's
1. cells in the islets of Langerhans that secrete glucagon.
2. acidophilic cells of the anterior pituitary.
APUD c's
argentaffin c's
enterochromaffin cells containing cytoplasmic granules capable of reducing silver compounds, located throughout the gastrointestinal tract, chiefly in the basilar portions of the gastric glands and the crypts of Lieberkühn. They secrete serotonin.
band cell
an immature neutrophil in which the nucleus is not lobulated but is in the form of a continuous band, horseshoe shaped, twisted or coiled. Called also band-form granulocyte and stab cell.
basal cell
an early keratinocyte, present in the basal layer of the epidermis.
basket c's
cells in the cerebellar cortex whose axons carry basket-like groups of fibrils which enclose the cell body of each Purkinje cell.
beta c's
1. basophilic cells in the pancreas that secrete insulin and make up most of the bulk of the islets of Langerhans; they contain granules that are soluble in alcohol.
2. basophilic cells of the anterior pituitary.
blood cell
one of the formed elements of the blood. See also blood.
cell body
the nucleus of the cell and the adjacent cytoplasm in cells which have processes, e g. neurons which consist of a cell body, an axon and dendrites.
bone cell
a nucleated cell in the lacunae of bone. Called also osteocyte.
cartilage cell
chondrocyte.
chromaffin c's
cells whose cytoplasm shows fine brown granules when stained with potassium bichromate, occurring in the adrenal medulla and in scattered groups in various organs and throughout the body.
cleavage cell
any of the cells derived from the fertilized ovum by mitosis; a blastomere.
cell culture
cell cycle
see cell cycle.
daughter cell
a cell formed by division of a mother cell.
cell dehydration
fluid loss from cells due to elevation of the osmotic pressure of blood and tissue fluid; a potent stimulus to thirst.
dendritic cell
macrophage-like cells with long, filamentous processes located in the cortex of lymph nodes and the skin. Important in antigen trapping, processing and presentation. See also langerhans' cell.
cell differentiation
the process whereby cells become specialized usually with concurrent loss of reproductive capacity.
embryonic stem cell
a stem cell of fetal origin. See stem cell (below).
epithelioid cell
enlarged macrophages with enlarged lysosomes and much endoplasmic reticulum. May fuse to form multinucleated giant cell (below).
epsilon cell
one of the groups of acidophilic cells in the adenohypophysis. Contains granules that stain with azocarmine dye.
foam cell
a cell with a vacuolated appearance due to the presence of complex lipoids; seen in xanthoma.
cell fusion
see syncytial giant cell.
ganglion cell
a large nerve cell, especially one of those of the spinal ganglia.
germ cell
see germ cell.
giant cell
a very large, multinucleate cell; applied to megakaryocytes of bone marrow, to giant cells formed by coalescence and fusion of macrophages occurring in infectious granulomas and about foreign bodies, and to certain cancer cells.
glial c's
neuroglial cells.
goblet cell
a unicellular mucous gland found in the epithelium of various mucous membranes, especially that of the respiratory passages and intestines.
granular cell
one containing granules, such as a keratinocyte in the stratum granulosum of the epidermis, when it contains a dense collection of darkly staining granules.
gustatory cell
see taste bud.
heart failure c's, heart lesion c's
iron-containing, rust-colored macrophages found in the pulmonary alveoli in congestive heart failure.
helmet cell
schistocyte.
helper cell
a subset of T lymphocytes which cooperate with B and other T lymphocytes for the synthesis of antibodies to many antigens; they play an integral role in immunoregulation.
hybrid cell
a mononucleate cell produced from a binucleate heterokaryon after the latter undergoes mitosis. Such cells are initially unstable, tending to lose randomly some of the double complement of chromosomes. Used for mapping genes to particular chromosomes. See also heterokaryon, hybridoma.
immunologically competent cell
interstitial c's
the cells of the connective tissue of the ovary or of the testis (Leydig's cells) which furnish the internal secretion of those structures, i.e. testosterone.
islet c's
cells composing the islets of Langerhans in the pancreas. See alpha cells, beta cells (above).
juxtaglomerular c's
specialized cells, containing secretory granules, located in the tunica media of the afferent glomerular arterioles. They cause aldosterone production by secreting the enzyme renin and play a role in the regulation of blood pressure and fluid balance.
K c's, killer c's
T lymphocytes or null lymphocytes that have cytotoxic activity against target cells coated with specific IgG antibody.
lacis cell
accumulation of cells between the arterioles at the glomerular hilus. Called also granular cell.
lacunar cell
precursor of the malignant interdigitating reticular cell in Hodgkin-like lymphoma in humans.
LE cell
a mature neutrophilic polymorphonuclear leukocyte characteristic of lupus erythematosus. See also lupus erythematosus (le) cell.
Leydig's c's
interstitial cells of the testis, which secrete testosterone.
cell line
lutein c's
the plump, pale-staining, polyhedral cells of the corpus luteum.
lymph cell
lymphocyte.
lymphoid c's
lymphocytes and plasma cells.
mast cell
a connective tissue cell that has basophilic, metachromatic cytoplasmic granules that contain histamine, heparin, hyaluronic acid, slow-reacting substance of anaphylaxis (SRS-A), and, in some species, serotonin. Have Fc receptors specific for IgE in the cell membrane.
cell-mediated immune reaction
see cellular immunity.
cell migration
movement of cells from their place of origin to other tissues; one of the fundamental processes of development.
microglial cell
see microglia. See also neuroglia cells (below).
milk cell count
mother cell
a cell that divides to form new, or daughter, cells.
Mott cell
a plasma cell with large, clear cytoplasmic pockets.
natural killer c's, NK c's
cells capable of mediating cytotoxic reactions without themselves being specifically sensitized against the target.
nerve cell
any cell of the nervous system; a neuron.
cell nests
neuroglia c's, neuroglial c's
null c's
lymphocyte-like cells that lack specific antigen receptors and other surface markers characteristic of B and T lymphocytes; they include K and NK cells; their numbers are elevated in active systemic lupus erythematosus and other disease states.
olfactory c's
a set of specialized cells of the mucous membrane of the nose; the receptors for smell.
parafollicular c's
see c cell.
Pick's c's
round, oval or polyhedral cells with foamy, lipid-containing cytoplasm found in the bone marrow and spleen in Niemann-Pick disease.
plasma cell
a spherical or ellipsoidal cell with a single, eccentrically placed nucleus containing dense masses of chromatin in a wheel-spoke arrangement, an area of perinuclear clearing which contains the Golgi apparatus, and generally abundant cytoplasm. Plasma cells are produced by cell division of B lymphocytes following antigen stimulation and are involved in the synthesis and release of antibody. Called also plasmacyte and plasmocyte.
prickle cell
a dividing keratinocyte of the prickle-cell layer of the epidermis, with delicate radiating process connecting with other similar cells.
prokaryotic cell
Purkinje's c's
large branching cells of the middle layer of the cerebellar cortex.
red cell, red blood cell
erythrocyte.
Reed-Sternberg c's
giant histiocytic cells, typically multinucleate, which are the common histological characteristic of Hodgkin's disease in humans.
reticular c's
the cells forming the reticular fibers of connective tissue; those forming the framework of lymph nodes, bone marrow and spleen. They are weakly phagocytic, stromal in origin and are distinct from the monocyte-macrophage system.
reticuloendothelial cell
Schwann cell
any of the large nucleated cells whose cell membrane spirally enwraps the axons of myelinated peripheral neurons supplying the myelin sheath between two nodes of Ranvier.
Sertoli c's
elongated cells in the tubules of the testes to which the spermatids become attached; they provide support, protection and, apparently, nutrition until the spermatids are transformed into mature spermatozoa.
sickle cell
a crescentic or sickle-shaped erythrocyte seen in some humans and deer. The abnormal shape caused by the presence of varying proportions of hemoglobin S.
signet-ring cell
a cell in which the nucleus has been pressed to one side by an accumulation of intracytoplasmic mucin.
somatic c's
the cells of the body other than the germ cells.
cell sorting
see fluorescence-activated cell sorter.
cell specialization
conversion of a simple cell type into a specialized cell type capable of a special function, e.g. a secretory cell; a major part of the growth of an embryo and the differentiation of basic mesenchymal tissue into specialized organs.
spindle cell
spindle shaped cells of the dermis or subcutis; principal component of spindle cell tumors.
spur cell
spiculed mature erythrocyte.
squamous c's
flat, scalelike epithelial cells.
stab cell
see band cell (above).
stellate cell
any star-shaped cell, as a Kupffer cell or astrocyte, having many filaments extending in all directions.
stem cell
1. any precursor cell.
2. a primitive hematopoietic cell that is capable of self-replicating or differentiating into precursor cells of erythrocytes or any of the leukocytes.
stipple cell
an erythrocyte containing granules that take a basic or bluish stain with Wright's stain.
suppressor c's
a not well defined subset of T lymphocytes that are reported to inhibit antibody and cell-mediated immune responses. They may play a role in immunoregulation, and are believed to be abnormal in various autoimmune and other immunological disease states. See also T lymphocytes.
target cell
1. an abnormally thin erythrocyte showing, when stained, a dark center and a peripheral ring of hemoglobin, separated by a pale, unstained zone containing less hemoglobin; seen in various anemias and other disorders. Called also codocyte.
2. any cell selectively affected by a particular agent, such as a hormone or drug.
3. cell containing nonself antigens in its cell membranes that is a target for nonimmune and immune cytolysis, e.g. virus-infected or tumor cell.
taste c's
cells in the taste buds associated with the nerves of taste.
cell therapy
see glandular therapy.
totipotential cell
an embryonic cell that is capable of developing into any type of body cell.
Türk's cell
a lymphocyte with increased basophilia.
visual c's
the neuroepithelial elements of the retina.
white cell, white blood cell
leukocyte.
References in periodicals archive ?
Stem cell therapy must undergo a range of stringent regulations before approval and commercialization.
4 million), these programs have the potential to accelerate the growth of the cell therapy industry to generate health and wealth," said CEO Keith Thompson of the Cell Therapy Catapult.
Currently, there are nearly 17 approved cell therapy products in the USA, 12 in Europe and 8 in other parts of the world like S.
The number of companies involved in cell therapy has increased remarkably during the past few years.
The research team also interviewed parents, finding 21 (11 percent) who said their children had received cell therapy at some point in their lives.
The stem cell therapy market is niche industry with a growing number of global and local companies involved in the development and commercialization of stem cell therapy products.
Moreover, development of advanced genomic methods for stem cell analysis and high number of ongoing research activities are further fueling the growth of the stem cell therapy market in North America.
In addition, based on the therapeutic applications, the global stem cell therapy market is segmented into eye diseases, metabolic diseases, GIT diseases, musculoskeletal disorders, immune system diseases, CNS diseases, CVS diseases, wounds and injuries, and others.
The goal of this report is to review the market for cell therapy products using screening reagents and instruments for analysis of individual components in tissue samples, blood, serum or plasma.
Progenitor Cell Therapy, LLC, a leading full-service provider for the contract development and manufacture of cell therapies, and Invitrogen Corporation (Nasdaq:IVGN), a global leader in life sciences, today announced they have entered into a strategic comarketing and development relationship.
In all likelihood, the PLX technology is immunologically privileged and offers a significant advantage to patients facing immune reactions to cell therapy such as autoimmune disorders.
OTCBB:PLRS), a cell therapy company dedicated to the commercialization of stem cell products, today announced that it has submitted a Pre-Investigational New Drug (Pre-IND) document to the Food and Drug Administration (FDA) for PLX-I, the Company's first product.