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Lactoferrin is a glycoprotein that belongs to the transferrin family of iron binding proteins. It is found in human breast milk as well as most epithelial surface secretions including tears, nasogastric, saliva, and bronchial. Lactoferrin binds 2 molecules of iron with very high affinity. Lactoferrin inhibits bacterial growth by withholding iron, its N-terminal region is an antimicrobial peptide. Lactotransferrin acts synergistically with lysozyme to potentiate the activity of both proteins. The multifunctional protein lactoferrin has many physiological possible roles. It is often referred to as an innate defense protein and frequently serves as the first line of defense in protection against pathogens. It has been shown to have the ability to bind iron, it is a natural anti-bacterial, anti-fungal and anti-viral, it is an antioxidant and it also has immunomodulatory properties. It has many beneficial properties, which make it a good candidate for a number of product applications. Considerable research is currently going on to explain the various suggested biological functions of lactoferrin.

Lactoferrin is a glycoprotein that belongs to the transferrin family of iron binding proteins. It is found in human breast milk as well as most epithelial surface secretions including tears, nasogastric, saliva, and bronchial. Lactoferrin binds 2 molecules of iron with very high affinity. Lactoferrin inhibits bacterial growth by withholding iron, its N-terminal region is an antimicrobial peptide. Lactotransferrin acts synergistically with lysozyme to potentiate the activity of both proteins. The multifunctional protein lactoferrin has many physiological possible roles. It is often referred to as an innate defense protein and frequently serves as the first line of defense in protection against pathogens. It has been shown to have the ability to bind iron, it is a natural anti-bacterial, anti-fungal and anti-viral, it is an antioxidant and it also has immunomodulatory properties. It has many beneficial properties, which make it a good candidate for a number of product applications. Considerable research is currently going on to explain the various suggested biological functions of lactoferrin.

Lactoferrin is a glycoprotein that belongs to the transferrin family of iron binding proteins. It is found in human breast milk as well as most epithelial surface secretions including tears, nasogastric, saliva, and bronchial. Lactoferrin binds 2 molecules of iron with very high affinity. Lactoferrin inhibits bacterial growth by withholding iron, its N-terminal region is an antimicrobial peptide. Lactotransferrin acts synergistically with lysozyme to potentiate the activity of both proteins. The multifunctional protein lactoferrin has many physiological possible roles. It is often referred to as an innate defense protein and frequently serves as the first line of defense in protection against pathogens. It has been shown to have the ability to bind iron, it is a natural anti-bacterial, anti-fungal and anti-viral, it is an antioxidant and it also has immunomodulatory properties. It has many beneficial properties, which make it a good candidate for a number of product applications. Considerable research is currently going on to explain the various suggested biological functions of lactoferrin.

Lactoferrin is a glycoprotein that belongs to the transferrin family of iron binding proteins. It is found in human breast milk as well as most epithelial surface secretions including tears, nasogastric, saliva, and bronchial. Lactoferrin binds 2 molecules of iron with very high affinity. Lactoferrin inhibits bacterial growth by withholding iron, its N-terminal region is an antimicrobial peptide. Lactotransferrin acts synergistically with lysozyme to potentiate the activity of both proteins. The multifunctional protein lactoferrin has many physiological possible roles. It is often referred to as an innate defense protein and frequently serves as the first line of defense in protection against pathogens. It has been shown to have the ability to bind iron, it is a natural anti-bacterial, anti-fungal and anti-viral, it is an antioxidant and it also has immunomodulatory properties. It has many beneficial properties, which make it a good candidate for a number of product applications. Considerable research is currently going on to explain the various suggested biological functions of lactoferrin.

Luciferase is a general term for the class of oxidative enzymes used in bioluminescence and is distinct from a photoprotein. Luciferase catalyzes a bioluminescent reaction which involves the substrate luciferin as well as Mg2+ and ATP, produces green light with a wavelength of 562 nm. Luciferase from firefly is broadly used as a reporter for studying gene regulation and function, and for pharmaceutical screening.

Luciferase is a general term for the class of oxidative enzymes used in bioluminescence and is distinct from a photoprotein. Luciferase catalyzes a bioluminescent reaction which involves the substrate luciferin as well as Mg2+ and ATP, produces green light with a wavelength of 562 nm. Luciferase from firefly is broadly used as a reporter for studying gene regulation and function, and for pharmaceutical screening.

Lumican also known as LUM belongs to the small leucine-rich proteoglycan (SLRP) family which comprises decorin, biglycan, fibromodulin, keratocan, epiphycan, and osteoglycin. Furthermore we can see that in these bifunctional molecules, the protein moiety binds collagen fibrils and the highly charged hydrophilic glycosaminoglycans regulate interfibrillar spacings. Lumican is the main keratan sulfate proteoglycan of the cornea however LUM is also distributed in interstitial collagenous matrices throughout the body. Lumican regulates collagen fibril organization and circumferential growth, corneal transparency, epithelial cell migration and tissue repair. Among the diseases associated with LUM is posterior amorphous corneal dystrophy.

Lumican also known as LUM belongs to the small leucine-rich proteoglycan (SLRP) family which comprises decorin, biglycan, fibromodulin, keratocan, epiphycan, and osteoglycin. Furthermore we can see that in these bifunctional molecules, the protein moiety binds collagen fibrils and the highly charged hydrophilic glycosaminoglycans regulate interfibrillar spacings. Lumican is the main keratan sulfate proteoglycan of the cornea however LUM is also distributed in interstitial collagenous matrices throughout the body. Lumican regulates collagen fibril organization and circumferential growth, corneal transparency, epithelial cell migration and tissue repair. Among the diseases associated with LUM is posterior amorphous corneal dystrophy.

Lumican also known as LUM is a part of the small leucine-rich proteoglycan (SLRP) family which comprises decorin, biglycan, fibromodulin, keratocan, epiphycan, and osteoglycin. Furthermore, we can see that in these bifunctional molecules, the protein moiety binds collagen fibrils and the highly charged hydrophilic glycosaminoglycans regulate interfibrillar spacings. Lumican is the main keratan sulfate proteoglycan of the cornea however LUM is also distributed in interstitial collagenous matrices throughout the body. Lumican regulates collagen fibril organization and circumferential growth, corneal transparency, epithelial cell migration and tissue repair.

Mouse Lungkine/CXCL15 (WECHE) belongs to the ELR motif-containing CXC chemokines. The mouse Lungkine gene has been mapped to chromosome 5. The cDNA of mouse Lungkine encodes a 166 amino acids (aa) protein with a 25 aa predicted signal peptide and a 141 aa mature protein with an exceptionally long C-terminal tail which extends beyond beyond the chemokine fold. Lungkine protein is secreted into bronchoalveolar space and is involved in lung-specific neutrophils trafficking. Furthermore, studies in Lungkine knockout mice propose that Lungkine is an imperative mediator of neutrophil migration from the lung parenchyma into the airspace. In addition, Lungkine is chemotactic for bone marrow progenitor cells and modulates hematopoietic cell differentiation. By Northern blot analysis and in-situ hybridization, Lungkine transcripts have only been specifically detected in the adult and fetal lung, and its expression is up-regulated under inflammatory conditions. There is a 35% aa sequence similarity between the mouse Lungkine and the human ENA-78 and a 31% similarity with the human IL-8.

Lxn also known as Latexin is a member of the protease inhibitor I47 (latexin) family. Lxn's function is hardly reversible, non-competitive, as well as potent inhibitor of CPA1, CPA2 and CPA4. Furthermore, Lxn plays a role in inflammation. Among the diseases associated with LXN are endocervicitis and listeriosis.

LY6D encloses 1 UPAR/Ly6 domain and is only expressed at the keratinocyte of stratified squamous epithelia and the outer cell surface of transitional epithelia. LY6D performs as a specification marker at earliest stage specification of lymphocytes between B- and T-cell developments.

Myeloid differentiation antigen Gr1 (Ly6G) is a GPI-anchored protein, which is briefly expressed on monocytes in the bone marrow. The level of the Ly6G expression in the bone marrow completely correlates with granulocyte differentiation and maturation. Ly6G ligation on murine neutrophils inhibits neutrophil recruitment, thus providing the first evidence of a function for the Ly6G molecule. Ly6G is seen primarily on neutrophils, also in a subgroup of eosinophils, differentiating pre-monocytes and plasmacytoid dendritic cells.

Myeloid differentiation antigen Gr1 (Ly6G) is a GPI-anchored protein, which is briefly expressed on monocytes in the bone marrow. The level of the Ly6G expression in the bone marrow completely correlates with granulocyte differentiation and maturation. Ly6G ligation on murine neutrophils inhibits neutrophil recruitment, thus providing the first evidence of a function for the Ly6G molecule. Ly6G is seen primarily on neutrophils, also in a subgroup of eosinophils, differentiating pre-monocytes and plasmacytoid dendritic cells.

The human Lymphocyte Antigen 6 Complex Locus G6F (LY6G6F) protein is a type I transmembrane protein belonging to the immunoglobin (Ig) superfamily, which contains cell-surface proteins involved in the immune system and cellular recognition. The LY6G6F protein has a role in the downstream signal transduction pathways involving GRB2 and GRB7.

LY86 is vital for effective CD180 cell surface expression and is vastly expressed in B-cells, tonsil and monocytes. LY86 collaborate with TLR4 and CD180 to facilitate the essential immune response to bacterial lipopolysaccharide (LPS) and cytokine production.

Lymphocyte Antigen 9, also known as LY9 is a member of the SLAM family of immunomodulatory receptors, LY9 interacts with the adaptor molecule SAP . LY9 plays a part in adhesion reactions between T lymphocytes and accessory cells via homophilic interaction. LY9 promotes T-cell differentiation into a helper T-cell Th17 phenotype which leads to increased IL-17 secretion; the costimulatory activity requires SH2D1A. Furthermore it also promotes recruitment of RORC to the IL-17 promoter. LY9 is implicated in the maintenance of peripheral cell tolerance through serving as a negative regulator of the immune response. LY9 disables autoantibody responses as well as inhibits IFN-gamma secretion by CD4(+) T-cells. Moreover, LY9 negatively regulate the size of thymic innate CD8(+) T-cells and the development of invariant natural killer T (iNKT) cells. Systemic Lupus Erythematosus is one of the diseases which are associated with LY9.

lysozyme G-like 2 and LYGH (LYG2), is a member of the glycosyl hydrolase 23 family. Lysozyme takes part in human innate immunity by causing bacterial cell lysis. LYG2 contains a SLT domain, a protein domain present in bacterial lytic transglycosylase (SLT) and in eukaryotic lysozymes (GEWL). SLT domain catalyzes the cleavage of the beta-1,4-glycosidic bond between N-acetylmuramic acid (MurNAc) and N-acetyglucosamine (GlcNAc).

Chemokine (C motif) ligand (XCL1) is a small cytokine belonging to the XC chemokine family that is also known as lymphotactin. It is found in high levels in spleen, thymus, intestine and peripheral blood leukocytes, and at lower levels in lung, prostate gland and ovary. Cellular sources for XCL1 include activated thymic and peripheral blood CD8+ T cells. This chemokine attracts T cells. In humans, XCL1 is closely related to another chemokine called XCL2, whose geneis found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

XCL1 is a small cytokine belonging to the XC chemokine family that is also known as lymphotactin. It is located in high levels in spleen, thymus, intestine and peripheral blood leukocytes, and at lower levels in lung, prostate gland and ovary. Cellular sources for XCL1 include activated thymic and peripheral blood CD8+ T cells. This chemokine attracts T cells. In humans, XCL1 is closely related to another chemokine called XCL2, whose gene is found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

XCL1 is a small cytokine belongs to the XC chemokine family that is also known as lymphotactin. XCL1 is found in high levels in spleen, thymus, intestine and peripheral blood leukocytes, and at lower levels in lung, prostate gland and ovary. Cellular sources for XCL1 include activated thymic and peripheral blood CD8+ T cells. This chemokine attracts T cells. In humans, XCL1 is closely related to XCL2, whose gene is found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

XCL1 is a small cytokine belongs to the XC chemokine family that is also known as lymphotactin. XCL1 is found in high levels in spleen, thymus, intestine and peripheral blood leukocytes, and at lower levels in lung, prostate gland and ovary. Cellular sources for XCL1 include activated thymic and peripheral blood CD8+ T cells. This chemokine attracts T cells. In humans, XCL1 is closely related to XCL2, whose gene is found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

Tyrosine-protein kinase Lyn (LYN) belongs to the src family of non-receptor protein tyrosine kinases, which is primarily expressed in haematopoietic tissues. LYN protein is involved in induction of stress-activated protein kinase (SAPK), but not ERK or p38 MAPK, in response to genotoxic agents. LYN protein stimulates SAPK by a MKK7- and MEKK1-dependent mechanism. The LYN - MEKK1 - MKK7 - SAPK pathway is efficient in the induction of apoptosis by genotoxic agents.

LYPLA1 is lysophospholipase which performs on biological membranes to regulate the multifunctional lysophospholipids. LYPLA1 protein hydrolyzes fatty acids from S-acylated cysteine residues in proteins like trimeric G alpha proteins or HRAS and in addition has depalmitoylating activity.

Acyl-protein thioesterase 2 (LYPLA2) is lysophospholipase which acts on biological membranes to regulate the multifunctional lysophospholipids. LYPLA2 may hydrolyze fatty acids from S-acylated cysteine residues in proteins such as trimeric G alpha proteins or HRAS.

Lysophospholipase-like protein 1 (LYPLAL1) is a member of the AB hydrolase 2 family. LYPLAL1 doesn’t exhibit phospholipase nor triacylglycerol lipase activity, able to hydrolyze only short chain substrates as a result of its shallow active site.

Lysostaphin, an endopeptidase specific for the cell wall peptidoglycan of staphylococci, is an extremely potent anti-staphylococcal agent. Lysostaphin is used as a research and diagnostic tool. Because it lyses staphylococci efficiently, it is widely used when preparing staphylococcal DNA or other cellular components for genetic and biochemical studies and for the preparation of protoplasts for transformation. Preparation and analysis of bacterial DNA has become a powerful tool used by clinical and other microbiologists in epidemiological studies aimed at tracing sources of infection or bacterial contamination.

Lysozymeis an antimicrobial enzyme produced by animals that are part of the innate immune system. Lysozyme is a glycoside hydrolase that catalyzes the hydrolysis of 1,4-beta-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in peptidoglycan, which is the major component of gram-positive bacterial cell wall.Lysozymes have primarily a bacteriolytic function - those in tissues and body fluids are associated with the monocyte-macrophage system and enhance the activity of immunoagents.

LYVE-1 has been identified as a major receptor for HA (extracellular matrix glycosaminoglycan hyaluronan) on the lymph vessel wall. The deduced amino acid sequence of LYVE-1 predicts a 322-residue type I integral membrane polypeptide 41% similar to the CD44 HA receptor with a 212-residue extracellular domain containing a single Link module the prototypic HA binding domain of the Link protein superfamily. Like CD44, the LYVE-1 molecule binds both soluble and immobilized HA. However, unlike CD44, the LYVE-1 molecule colocalizes with HA on the luminal face of the lymph vessel wall and is completely absent from blood vessels. Hence, LYVE-1 is the first lymph-specific HA receptor to be characterized and is a uniquely powerful marker for lymph vessels themselves.

LYVE-1 has been identified as a major receptor for HA (extracellular matrix glycosaminoglycan hyaluronan) on the lymph vessel wall. The deduced amino acid sequence of LYVE-1 predicts a 322-residue type I integral membrane polypeptide 41% similar to the CD44 HA receptor with a 212-residue extracellular domain containing a single Link module the prototypic HA binding domain of the Link protein superfamily. Like CD44, the LYVE-1 molecule binds both soluble and immobilized HA. However, unlike CD44, the LYVE-1 molecule colocalizes with HA on the luminal face of the lymph vessel wall and is completely absent from blood vessels. Hence, LYVE-1 is the first lymph-specific HA receptor to be characterized and is a uniquely powerful marker for lymph vessels themselves.

LYVE1 is a selective marker of the lymphatic endothelium & a surface endocytic receptor for both soluble and immobilized hyaluronan, LYVE1 is an extracellular glycosaminoglycan that plays a role in cell adhesion and migration. LYVE1 functions in lympathic hyaluronan transport and is involved in tumor metastasis. Recombinant human LYVE1 was expressed in and purified by conventional chromatography techniques. The normal adult human choroid is endowed with a significant number of LYVE-1 positive macrophages. LYVE-1 is expressed in a reticulum cell neoplasm in an axillary lymph node. This reticulum cell sarcoma is a lymphatic sinus lining cell sarcoma which might represent another subtype of reticulum cell sarcomas.
LYVE-1 immunohistochemistry is a functional method for detecting lymphatics invaded by cancer cells, and detailed examination of the submucosa around the tumor is important for predicting LN metastasis.

LYVE-1 has been identified as a major receptor for HA (extracellular matrix glycosaminoglycan hyaluronan) on the lymph vessel wall. The deduced amino acid sequence of LYVE-1 predicts a 322-residue type I integral membrane polypeptide 41% similar to the CD44 HA receptor with a 212-residue extracellular domain containing a single Link module the prototypic HA binding domain of the Link protein superfamily. Like CD44, the LYVE-1 molecule binds both soluble and immobilized HA. However, unlike CD44, the LYVE-1 molecule colocalizes with HA on the luminal face of the lymph vessel wall and is completely absent from blood vessels. Hence, LYVE-1 is the first lymph-specific HA receptor to be characterized and is a uniquely powerful marker for lymph vessels themselves.

LZIC is a member of the CTNNBIP1 family. LZIC protein is universally expressed, with largest levels in kidney and up-regulated in various cases of gastric cancers. LZIC has no interaction with CTNNB1.

Leucine Zipper Transcription Factor-Like 1, also known as LZTFL1 is a ubiquitously expressed protein which localizes to the cytoplasm. LZTFL1 interacts with Bardet-Biedl Syndrome proteins (BBS) and during its interaction with BBS protein complexes, regulates protein trafficking to the ciliary membrane. Nonsense mutations in LZTFL1 cause a form of Bardet-Biedl Syndrome; a ciliopathy characterized partly by polydactyly, obesity, cognitive impairment, hypogonadism, and kidney failure. LZTFL1 also acts as a tumor suppressor; possibly by interacting with E-cadherin as well as the actin cytoskeleton and in this manner regulating the transition of epithelial cells to mesenchymal cells.

Granulocyte/Macrophage Colony-Stimulating Factors are cytokines that act in hematopoiesis by controlling the production, differentiation, and function of 2 related white cell populations of the blood, the granulocytes and the monocytes-macrophages. MCSF induces cells of the monocyte/macrophage lineage. MCSF plays a role in immunological defenses, bone metabolism, lipoproteins clearance, fertility and pregnancy.

Granulocyte/Macrophage Colony-Stimulating Factors are cytokines that act in hematopoiesis by controlling the production, differentiation, and function of 2 related white cell populations of the blood, the granulocytes and the monocytes-macrophages. CSF-1 induces cells of the monocyte/macrophage lineage. It plays a role in immunological defenses, bone metabolism, lipoproteins clearance, fertility and pregnancy.

Granulocyte/Macrophage Colony-Stimulating Factors are cytokines that act in hematopoiesis by controlling the production, differentiation, and function of 2 related white cell populations of the blood, the granulocytes and the monocytes-macrophages. CSF-1 induces cells of the monocyte/macrophage lineage. It plays a role in immunological defenses, bone metabolism, lipoproteins clearance, fertility and pregnancy.

Granulocyte/Macrophage Colony-Stimulating Factors are cytokines that act in hematopoiesis by controlling the production, differentiation, and function of 2 related white cell populations of the blood, the granulocytes and the monocytes-macrophages. MCSF induces cells of the monocyte/macrophage lineage. MCSF plays a role in immunological defenses, bone metabolism, lipoproteins clearance, fertility and pregnancy.

Granulocyte/Macrophage Colony-Stimulating Factors are cytokines that act in hematopoiesis by controlling the production, differentiation, and function of 2 related white cell populations of the blood, the granulocytes and the monocytes-macrophages. CSF-1 induces cells of the monocyte/macrophage lineage. It plays a role in immunological defenses, bone metabolism, lipoproteins clearance, fertility and pregnancy.

Granulocyte/Macrophage Colony-Stimulating Factors are cytokines that act in hematopoiesis by controlling the production, differentiation, and function of 2 related white cell populations of the blood, the granulocytes and the monocytes-macrophages. MCSF induces cells of the monocyte/macrophage lineage. MCSF plays a role in immunological defenses, bone metabolism, lipoproteins clearance, fertility and pregnancy.

Granulocyte/Macrophage Colony-Stimulating Factors are cytokines that act in hematopoiesis by controlling the production, differentiation, and function of 2 related white cell populations of the blood, the granulocytes and the monocytes-macrophages. CSF-1 induces cells of the monocyte/macrophage lineage. It plays a role in immunological defenses, bone metabolism, lipoproteins clearance, fertility and pregnancy.

Mycobacterium tuberculosis, a member of the Mycobacteriaceae family, is an important infectious pathogenic bacteria and the cause for most cases of tuberculosis. It is the second common cause of death from an infectious disease in the world. Diagnosis using patient’s specimen culture of M. tuberculosis are still considered gold standard, but it is expensive and time-consuming. RV-1681 is a protein released from M. tuberculosis on infected organ, which filtrates through into the urine after circulating in the blood flow, to the kidney.RV-1681 is considered to be a reliable marker for M. tuberculosis diagnosis allowing easy low cost and time saving urine testing to screen large population for M. tuberculosis infection.

Mycoplasma pneumonia is part of the atypical pneumonia subtype which is caused by the bacteria M. pneumoniae. Mycoplasma pneumonia affects individuals younger than 40. It makes up 15 - 50% of all pneumonia cases in adults and especially in school-aged children. People at great risk for mycoplasma pneumonia comprise of those living or working in busy areas such as schools and homeless shelters, although many people who contract mycoplasma pneumonia have no identifiable risk factor. P1, P30, and P116 of mycoplasma pneumonia membrane proteins have been recognized as adhensive factors, P1 is considered as a main adhension protein of the organism colonization.

Mycoplasma pneumonia is part of the atypical pneumonia subtype which is caused by the bacteria M. pneumoniae. Mycoplasma pneumonia affects individuals younger than 40. It makes up 15 - 50% of all pneumonia cases in adults and especially in school-aged children. People at great risk for mycoplasma pneumonia comprise of those living or working in busy areas such as schools and homeless shelters, although many people who contract mycoplasma pneumonia have no identifiable risk factor. P1, P30, and P116 of mycoplasma pneumonia membrane proteins have been recognized as adhensive factors, P1 is considered as a main adhension protein of the organism colonization.

Mycoplasma pneumonia is part of the atypical pneumonia subtype which is caused by the bacteria M. pneumoniae. Mycoplasma pneumonia affects individuals younger than 40. It makes up 15 - 50% of all pneumonia cases in adults and especially in school-aged children. People at great risk for mycoplasma pneumonia comprise of those living or working in busy areas such as schools and homeless shelters, although many people who contract mycoplasma pneumonia have no identifiable risk factor. P1, P30, and P116 of mycoplasma pneumonia membrane proteins have been recognized as adhesive factors, P1 is considered as a main adhesion protein of the organism colonization.

M2 autoantigen is a key mark of antimitochondrial autoantibodies (AMA), a typical serological feature in patients suffering from primary biliary cirrhosis (PBC) which is a serious autoimmune liver disease accompanied by damage to intrahepatic bile ducts. Molecular definition of the M2 antigen has displayed it as no less than 3 separate target proteins. The M2 role is like the so-called E2 subunits (or dihydrolipoamide transferases) of different mitochondrial dehydrogenase complexes:
*pyruvate dehydrogenase complex.
*branched chain 2-oxo-acid dehydrogenase complex.
*2-oxoglutarate dehydrogenase complex.
Biochemically, these complexes catalyze the oxidative decarboxylation of various alpha-keto-acid substrates and systematically engage with a prosthetic lipoamide group; they are situated in the mitochondrial matrix in association with the inner membrane. The most well-known reactivity of AMA positive PBC sera is against PDC-E2. Some patients have AMA which reacts with PDC-E2 alone (95%), but most patients also show reactivity against OGDC-E2 (39-88%) and/or BCOADC-E2 (53-55%). Actually, patients can be found with reactivity only against OGDC-E2 and/or BCOADC-E2 and no PDC-E2 autoantibodies. These patients will be overlooked in assays based on natural source-derived, predominantly PDC-E2-containing M2 antigen preparations.