Freund's adjuvant

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Freund's adjuvant is a solution of antigen emulsified in mineral oil and used as an immunopotentiator (booster). The complete form, Freund's Complete Adjuvant (FCA or CFA) is composed of inactivated and dried mycobacteria (usually M. tuberculosis ), whereas the incomplete form (FIA or IFA) lacks the mycobacterial components (hence just the water in oil emulsion). It is named after Jules T. Freund.

Contents

Regulation

Freund's complete adjuvant is effective in stimulating cell-mediated immunity and leads to potentiation of T helper cells that leads to the production of certain immunoglobulins and effector T cells. Its use in humans is forbidden by regulatory authorities, due to its toxicity. In animal research there are also strict guidelines associated with its use, due to its potential for pain and tissue damage. Injections of FCA should be subcutaneous or intraperitoneal, because intradermal injections may cause skin ulceration and necrosis; intramuscular injections may lead to temporary or permanent muscle lesion, and intravenous injections may produce pulmonary lipid embolism.[ citation needed ]

Effects

When administered to diabetes prone non-obese diabetic (NOD) mice, Freund's complete adjuvant (FCA) prevented juvenile-onset diabetes. [1] [2] When combined with spleen cells, FCA was said to have reversed diabetes. [3] In 2006, these claims were confirmed that even without spleen cells FCA can restore insulin producing beta cells in pancreas of NOD mice. [4] Although newspapers have described the 2006 findings as confirming the earlier experiments, [5] a report from NIH was released on November 23, 2006, in Science confirming the participation of spleen cells in reversing end-stage diabetes. [6] [7]

It has also been investigated in an animal model of Parkinson's disease, [8] or as well used in emulsion with Myelin oligodendrocyte glycoprotein (MOG), a peptide inducing Experimental autoimmune encephalomyelitis (EAE) in animal studies for efficacy testing of multiple sclerosis treatments. [9]

Mechanism

FCA is known to stimulate production of tumor necrosis factor, which is thought to kill the T-cells responsible for the autoimmune destruction of the pancreatic beta cells. Still in question is whether the regrowth of functional insulin-producing cells occurs due to differentiation and proliferation of existing pancreatic stem cells, or whether the injected spleen cells re-differentiate to an insulin-producing form. Denise Faustman, whose work has been central to developing the protocol, has suggested that both mechanisms may play a role. However, in experiments to verify and examine her work, Suri reported that DNA-based evidence yielded no sign that spleen cells were needed in pancreatic islet beta cells regeneration after the FCA treatment. [10] In pancreatic islets the β-cells regenerate following Freund's adjuvant treatment. [11] This is related to the induction of Th17 cells by adjuvant treatment and these cells produce Interleukin-22 (IL-22). Pancreatic islets express high levels of IL-22 receptor and IL-22 has been shown to induce islet beta cell regeneration. [12]

See also

Related Research Articles

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Insulin is a peptide hormone produced by beta cells of the pancreatic islets encoded in humans by the insulin (INS) gene. It is the main anabolic hormone of the body. It regulates the metabolism of carbohydrates, fats, and protein by promoting the absorption of glucose from the blood into cells of the liver, fat, and skeletal muscles. In these tissues the absorbed glucose is converted into either glycogen, via glycogenesis, or fats (triglycerides), via lipogenesis; in the liver, glucose is converted into both. Glucose production and secretion by the liver are strongly inhibited by high concentrations of insulin in the blood. Circulating insulin also affects the synthesis of proteins in a wide variety of tissues. It is thus an anabolic hormone, promoting the conversion of small molecules in the blood into large molecules in the cells. Low insulin in the blood has the opposite effect, promoting widespread catabolism, especially of reserve body fat.

<span class="mw-page-title-main">Pancreas</span> Organ of the digestive system and endocrine system of vertebrates

The pancreas is an organ of the digestive system and endocrine system of vertebrates. In humans, it is located in the abdomen behind the stomach and functions as a gland. The pancreas is a mixed or heterocrine gland, i.e., it has both an endocrine and a digestive exocrine function. 99% of the pancreas is exocrine and 1% is endocrine. As an endocrine gland, it functions mostly to regulate blood sugar levels, secreting the hormones insulin, glucagon, somatostatin and pancreatic polypeptide. As a part of the digestive system, it functions as an exocrine gland secreting pancreatic juice into the duodenum through the pancreatic duct. This juice contains bicarbonate, which neutralizes acid entering the duodenum from the stomach; and digestive enzymes, which break down carbohydrates, proteins and fats in food entering the duodenum from the stomach.

<span class="mw-page-title-main">Beta cell</span> Type of cell found in pancreatic islets

Beta cells (β-cells) are specialized endocrine cells located within the pancreatic islets of Langerhans responsible for the production and release of insulin and amylin. Constituting ~50–70% of cells in human islets, beta cells play a vital role in maintaining blood glucose levels. Problems with beta cells can lead to disorders such as diabetes.

<span class="mw-page-title-main">Pancreatic islets</span> Regions of the pancreas

The pancreatic islets or islets of Langerhans are the regions of the pancreas that contain its endocrine (hormone-producing) cells, discovered in 1869 by German pathological anatomist Paul Langerhans. The pancreatic islets constitute 1–2% of the pancreas volume and receive 10–15% of its blood flow. The pancreatic islets are arranged in density routes throughout the human pancreas, and are important in the metabolism of glucose.

<span class="mw-page-title-main">Alpha cell</span> Glucagon secreting cell

Alpha cells (α-cells) are endocrine cells that are found in the Islets of Langerhans in the pancreas. Alpha cells secrete the peptide hormone glucagon in order to increase glucose levels in the blood stream.

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<span class="mw-page-title-main">Type 1 diabetes</span> Form of diabetes mellitus

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<span class="mw-page-title-main">Streptozotocin</span> Chemical compound

Streptozotocin or streptozocin (STZ) is a naturally occurring alkylating antineoplastic agent that is particularly toxic to the insulin-producing beta cells of the pancreas in mammals. It is used in medicine for treating certain cancers of the islets of Langerhans and used in medical research to produce an animal model for hyperglycemia and Alzheimer's in a large dose, as well as type 2 diabetes or type 1 diabetes with multiple low doses.

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Biobreeding rat, also known as the BB or BBDP rat, is an inbred laboratory rat strain that spontaneously develops autoimmune Type 1 Diabetes. Like the NOD mice, BB rats are used as an animal model for Type 1 diabetes. The strain re-capitulates many of the features of human type 1 diabetes, and has contributed greatly to the research of T1D pathogenesis.

<span class="mw-page-title-main">PDX1</span> A protein involved in the pancreas and duodenum differentiation

PDX1, also known as insulin promoter factor 1, is a transcription factor in the ParaHox gene cluster. In vertebrates, Pdx1 is necessary for pancreatic development, including β-cell maturation, and duodenal differentiation. In humans this protein is encoded by the PDX1 gene, which was formerly known as IPF1. The gene was originally identified in the clawed frog Xenopus laevis and is present widely across the evolutionary diversity of bilaterian animals, although it has been lost in evolution in arthropods and nematodes. Despite the gene name being Pdx1, there is no Pdx2 gene in most animals; single-copy Pdx1 orthologs have been identified in all mammals. Coelacanth and cartilaginous fish are, so far, the only vertebrates shown to have two Pdx genes, Pdx1 and Pdx2.

<span class="mw-page-title-main">Free fatty acid receptor 2</span> Protein-coding gene in the species Homo sapiens

Free fatty acid receptor 2 (FFAR2), also termed G-protein coupled receptor 43 (GPR43), is a rhodopsin-like G-protein coupled receptor. It is coded by the FFAR2 gene. In humans, the FFAR2 gene is located on the long arm of chromosome 19 at position 13.12. Like other GPCRs, FFAR2s reside on the surface membrane of cells and when bond to one of their activating ligands regulate the function of their parent cells. FFAR2 is a member of a small family of structurally and functionally related GPRs termed free fatty acid receptors (FFARs). This family includes three other receptors which, like FFAR2, are activated by certain fatty acids: FFAR1, FFAR3 (GPR41), and FFAR4 (GPR120). FFAR2 and FFAR3 are activated by short-chain fatty acids whereas FFAR1 and FFAR4 are activated by long-chain fatty acids.

<span class="mw-page-title-main">Insulitis</span> Medical condition

Insulitis is an inflammation of the islets of Langerhans, a collection of endocrine tissue located in the pancreas that helps regulate glucose levels, and is classified by specific targeting of immune cell infiltration in the islets of Langerhans. This immune cell infiltration can result in the destruction of insulin-producing beta cells of the islets, which plays a major role in the pathogenesis, the disease development, of type 1 and type 2 diabetes. Insulitis is present in 19% of individuals with type 1 diabetes and 28% of individuals with type 2 diabetes. It is known that genetic and environmental factors contribute to insulitis initiation, however, the exact process that causes it is unknown. Insulitis is often studied using the non-obese diabetic (NOD) mouse model of type 1 diabetes. The chemokine family of proteins may play a key role in promoting leukocytic infiltration into the pancreas prior to pancreatic beta-cell destruction.

<span class="mw-page-title-main">Neurogenin-3</span> Mammalian protein found in Homo sapiens

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The regenerating protein family often abbreviated as Reg family are a group of small secretory proteins that are involved in the proliferation and differentiation of diverse cell types. In addition they are important in protecting cells from death caused by damage or inflammation.

<span class="mw-page-title-main">Brockmann body</span> Endocrine organ in some teleost fish

Brockmann body is an endocrine organ in some teleost fish, and is composed of a collection of islet tissues. The islet tissues are in turn composed of endocrine cells which are the principal sites of insulin synthesis. They are distributed around the spleen and the large intestine. They also secrete other hormones such as glucagon and somatostatin. Hence, Brochmann body is the centre of control of blood glucose level in these fishes. Glucagon is also produced from the intestine, but Brockmann body is the major source. Increased level of glucose stimulate the Brockmann body to release insulin, while inhibiting glucagon. Somatostatin released from Brockmann body inhibits cells to produce insulin and glucagon. In addition it inhibits release of growth hormone from the pituitary. It is named after a German physician Heinrich Brochmann who discovered it in 1848.

<span class="mw-page-title-main">Pancreatic progenitor cell</span>

Pancreatic progenitor cells are multipotent stem cells originating from the developing fore-gut endoderm which have the ability to differentiate into the lineage specific progenitors responsible for the developing pancreas.

<span class="mw-page-title-main">Pancreatic islet macrophage</span>

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References

  1. Sadelain, MW; Qin, HY; Lauzon, J; Singh, B (1990), "Prevention of type I diabetes in NOD mice by adjuvant immunotherapy", Diabetes, 39 (5): 583–589, doi:10.2337/diabetes.39.5.583, PMID   2139617
  2. Qin, HY; Sadelain, MW; Hitchon, C; Lauzon, J; Singh, B (1993), "Complete Freund's adjuvant-induced T cells prevent the development and adoptive transfer of diabetes in nonobese diabetic mice", J. Immunol., 150 (5): 2072–2080, doi: 10.4049/jimmunol.150.5.2072 , PMID   8436836, S2CID   9779509
  3. Kodama, S; Kühtreiber, W; Fujimura, S; Dale, EA; Faustman, DL (2003), "Islet Regeneration During the Reversal of Autoimmune Diabetes in NOD Mice", Science, 302 (5648): 1223–1227, Bibcode:2003Sci...302.1223K, doi:10.1126/science.1088949, PMID   14615542, S2CID   897696
  4. Couzin, J. (2006), "Diabetes Studies Conflict on Power of Spleen Cells", Science, 311 (5768): 1694, doi: 10.1126/science.311.5768.1694 , PMID   16556811, S2CID   10334900
  5. Kolata, G. (March 24, 2006), "A Controversial Therapy for Diabetes Is Verified", The New York Times, retrieved May 3, 2010
  6. New data from NIH lab confirms protocol to reverse type 1 diabetes in mice, BiologyNewsNet, November 2006
  7. Philip E. Ross, Putting Up with Self, Scientific American, November 12, 2006
  8. Armentero MT, Levandis G, Nappi G, Bazzini E, Blandini F (2006), "Peripheral inflammation and neuroprotection: systemic pretreatment with complete Freund's adjuvant reduces 6-hydroxydopamine toxicity in a rodent model of Parkinson's disease", Neurobiol. Dis., 24 (3): 492–505, doi:10.1016/j.nbd.2006.08.016, PMID   17023164, S2CID   7076941.
  9. Bittner, Stefan; Afzali, Ali M.; Wiendl, Heinz; Meuth, Sven G. (2014-04-15). "Myelin Oligodendrocyte Glycoprotein (MOG35-55) Induced Experimental Autoimmune Encephalomyelitis (EAE) in C57BL/6 Mice". Journal of Visualized Experiments (86): 51275. doi:10.3791/51275. ISSN   1940-087X. PMC   4172026 . PMID   24797125.
  10. Suri, A; Calderon, B; Esparza, TJ; Frederick, K; Bittner, P; Unanue, ER (2006), "Immunological Reversal of Autoimmune Diabetes Without Hematopoietic Replacement of β Cells", Science, 311 (5768): 1778–1780, Bibcode:2006Sci...311.1778S, doi:10.1126/science.1123500, PMID   16556846, S2CID   42150301
  11. Huszarik, K; Wright, B; Keller, C; Nikoopour, E (2010). "Adjuvant immunotherapy increases beta cell regenerative factor Reg2 in the pancreas of diabetic mice". J. Immunol. 185 (9): 5120–9. doi: 10.4049/jimmunol.1001596 . PMID   20876350.
  12. Hill, T; Krougly, O; Nikoopour, E; Bellemore, S (2013). "The involvement of interleukin-22 in the expression of pancreatic beta cell regenerative Reg genes". Cell Regeneration. 2 (1): 1–11. doi: 10.1186/2045-9769-2-2 . PMC   4230743 . PMID   25408874.