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Haptoglobin is a glycoprotein which is synthesized in the liver and circulates in the blood. Haptoglobin is produced typically by hepatocytes but also by other tissues: e.g. skin, lung, and kidney. It is a positive acute phase protein that binds free hemoglobin and removes it from the circulation to prevent kidney injury, and iron loss following hemolysis. The haptoglobin-hemoglobin complex is subsequently removed by the reticuloendothelial system (generally the spleen). As the reticuloendothelial system removes the haptoglobin-hemoglobin complex from the body, haptoglobin levels are reduced in hemolytic anaemias. In the course of binding hemoglobin, haptoglobin sequesters the iron inside hemoglobin, preventing iron-utilizing bacteria from benefitting from hemolysis.
Haptoglobin consists of two A- and two B-chains, connected by disulfide bonds. Three major haptoglobin phenotypes are known to exist (Hp 1-1, Hp 2-1, and Hp 2-2). Hp 1-1 is biologically the most effective in binding free hemoglobin and suppressing inflammatory responses associated with free hemoglobin. Hp 2-2 is biologically the least active, and Hp 2-1 is moderately active. Haptoglobin’s molecular mass ranges from 8-200 kDa.
Reduced levels can be seen in haemolysis and impaired liver function. High levels are a marker for acute or chronic inflammation. Ahaptoglobinemia or hypohaptoglobinemia are caused by mutations in the haptoglobin gene and/or its regulatory regions. Haptoglobin is also linked to diabetic nephropathy, the incidence of coronary artery disease in type 1 diabetes, Crohn's disease, inflammatory disease behavior, primary sclerosing cholangitis, susceptibility to idiopathic Parkinson's disease, and a reduced incidence of Plasmodium falciparum malaria.

Haptoglobin or HP is encoded by the HP gene in humans. Haptoglobin binds free hemoglobin (which is released from erythrocytes) in the blood plasma, therefore inhibits the Hb oxidative activity. The complex that contains Haptoglobin and hemoglobin will then be eliminated mostly through the spleen.

Haptoglogin participates in intestinal permeability, permitting intercellular tight junction disassembly, and controlling the equilibrium among tolerance and immunity to non-self antigens. Haptoglobin has antibacterial activity and takes part in modulating many aspects of the acute phase response. Haptoglobin is processed to yield both alpha and beta chains, which later unite as a tetramer to produce haptoglobin. Haptoglobin binds free hemoglobin (Hb) secreted from erythrocytes In blood plasma with high affinity and thus inhibits its oxidative activity. Further, the haptoglobin-hemoglobin complex is being removed by the reticuloendothelial system.

Haptoglobin-Related Protein also known as HPR, is a primate-specific plasma protein related with apolipoprotein L-I (apoL-I)-containing high-density lipoprotein (HDL) particles which shown to be a part of the innate immune defense. HPR-bound hemoglobin might contribute to the biologic activity of the circulating apoL-I/Hprcontaining HDL particles. HPR is a clinically significant forecaster of recurrence of breast cancer.

Myoglobin is a member of the globin superfamily and can be found in skeletal and cardiac muscles. It is a haemoprotein that contributs to intracellular oxygen storage and transcellular facilitated diffusion of oxygen. Myoglobin has a single-chain globular structure of 153 amino acids, containing a heme prosthetic group (iron-containing porphyrin) in the core around which the remaining apoprotein folds. Myoglobin has 8 alpha helices and a hydrophobic core. Myoglobin’s molecular weight is 16.7 kDa, and it is the primary oxygen-carrying pigment of muscle tissues. The binding of oxygen in myoglobin is different from the cooperative oxygen binding in hemoglobin, since positive collaboration is a property of multimeric/oligomeric proteins only. Instead, the binding of oxygen by myoglobin is uninfluenced by the oxygen pressure in the surrounding tissue. Myoglobin is frequently referred to as having an "instant binding tenacity" to oxygen given its hyperbolic oxygen dissociation curve. Different organisms are able to hold their breaths longer due to high concentrations of myoglobin in their muscle cells. Myoglobin is responsible for the pigments that make meat red. The color of the meat is partly determined by the charge of the iron atom in myoglobin and the oxygen attached to it. Myoglobin is found in Type I muscle, Type II A and Type II B, but it is mostly deemed that myoglobin is not found in smooth muscle. Myoglobin is discharged from damaged muscle tissue (rhabdomyolysis), which contains very high concentrations of myoglobin. Even though the released myoglobin is filtered by the kidneys, it is toxic to the renal tubular epithelium and thus may cause acute renal failure.

Transferrin is the iron-transport protein of vertebrate serum and donates iron to cells through interaction with a specific membrane receptor, CD71. Transferrin appears to be indispensable for most cells growing in tissue culture.
It is referred to frequently as a growth factor because, in analogy to other growth factor-receptor interactions, proliferating cells express high numbers of transferrin receptors, and the binding of transferrin to their receptors is needed for cells to initiate and maintain their DNA synthesis. Apart from its role as an iron transport protein transferrin acts as a cytokine and has functions that may not be related to its iron-carrying capacity.
Human Transferrin is a crucial component for the cultivation of mammalian cells in-vitro. Human Transferrin is Critical for long-term cells growth in-vitro. Human Transferrin is used as detoxificant in media by binding contaminating metal ions. Human Transferrin is often used as a nutrient in fermentation media for recombinant protein and biopharmaceutical production. Additional common uses of Human Transferrin areMolecular weight, Affinity purification of anti-human transferrin antibodies and also as receptor mediated transfection of molecules such as DNA, into cells.

HBQ1 is a member of the Hemoglobin family. Hemoglobin is a 66.7 kDa protein attached to four iron-binding, methenelinked tetrapyrrole rings (heme). The globin part of Hemoglobin contains 2 alpha chains and 2 beta chains organized as couples creating a tetramer. Every one of the 4 globin chains covalently connects with a heme group. The bonds between alpha and beta chains are frailer than between parallel globin chains, thus creating a cleavage plane which is vital for oxygen binding and release. Relaxation of the alpha1-beta2 cleavage plane results in high affinity for oxygen.

Secretoglobin Family 1D, Member 1 (SCGB1D1) belongs to the lipophilin subfamily, part of the uteroglobin superfamily, and is an ortholog of prostatein (which is the major secretory glycoprotein of the rat ventral prostate gland). SCGB1D1 binds androgens and other steroids. In addition SCGB1D1 binds chemotherapeutic drugs during the prostate cancer treatment. Steroid hormones regulate the SCGB1D1 transcription. SCGB1D1 is secreted into extracellular space. SCGB1D1 gene product represents one component of a heterodimeric molecule found in human tears whose elution profile is consistent with prostatein (which is a tetrameric molecule comprised of 3 peptide components in heterodimers).

Myoglobin is a member of the globin superfamily and can be found in skeletal and cardiac muscles. It is a haemoprotein that contributs to intracellular oxygen storage and transcellular facilitated diffusion of oxygen. Myoglobin has a single-chain globular structure of 153 amino acids, containing a heme prosthetic group (iron-containing porphyrin) in the core around which the remaining apoprotein folds. Myoglobin has 8 alpha helices and a hydrophobic core. Myoglobin’s molecular weight is 16.7 kDa, and it is the primary oxygen-carrying pigment of muscle tissues. The binding of oxygen in myoglobin is different from the cooperative oxygen binding in hemoglobin, since positive collaboration is a property of multimeric/oligomeric proteins only. Instead, the binding of oxygen by myoglobin is uninfluenced by the oxygen pressure in the surrounding tissue. Myoglobin is frequently referred to as having an "instant binding tenacity" to oxygen given its hyperbolic oxygen dissociation curve. Different organisms are able to hold their breaths longer due to high concentrations of myoglobin in their muscle cells. Myoglobin is responsible for the pigments that make meat red. The color of the meat is partly determined by the charge of the iron atom in myoglobin and the oxygen attached to it. Myoglobin is found in Type I muscle, Type II A and Type II B, but it is mostly deemed that myoglobin is not found in smooth muscle. Myoglobin is discharged from damaged muscle tissue (rhabdomyolysis), which contains very high concentrations of myoglobin. Even though the released myoglobin is filtered by the kidneys, it is toxic to the renal tubular epithelium and thus may cause acute renal failure.

Hemoglobin subunit gamma-2 (HBG2), is a member of the globin family. HBG2 belongs to the fetal hemoglobin subunit, which comprised of two alpha chains organized with 2 gamma chains. HBG2 Amplified fetal hemoglobin production in adults and improve the clinical severity of sickle cell disease and beta-thalassemia major.

Hemoglobin Subunit Zeta (Hbz) or Hba-x is a alpha-like hemoglobin and part of the globin family. The protein is expressed and produced in the the yolk sac in early stages of embryonic development. Hemoglobin subunit zeta has 2 pseudogenes and 5 functional genes.

Myoglobin, mitochondrial precursor is a cytosolic oxygen-binding protein in charge of the storage and diffusion of oxygen within myocytes. The largest expression of MB is in the skeletal and cardiac muscle. MB operates in various functions in muscular oxygen supply, such as oxygen storage, facilitated diffusion, and myoglobin-mediated oxidative phosphorylation.

Hemoglobin subunit zeta (HBZ) is part of the globin family. Hemoglobin Zeta is alpha-like hemoglobin. The HBZ polypeptide is synthesized in the yolk sac of the early embryo, while alpha-globin is produced throughout fetal and adult life.

The gamma globin genes which are HBG1 and HBG2, usually expressed in the fetal liver, spleen and bone marrow. 2 gamma chains together along with 2 alpha chains comprise fetal hemoglobin (HbF) which is normally replaced by mature hemoglobin (HbA) at birth. Gamma chain production continues into adulthood in several beta-thalassemias and linked situations. The two types of gamma chains differ at residue 136 where glycine is found in the G-gamma product (HBG2) and alanine is found in the A-gamma product (HBG1). The former is predominant at birth.

Myoglobin is a member of the globin superfamily and exists in skeletal and cardiac muscles. Myoglobin is a haemoprotein that contributs to intracellular oxygen storage and transcellular facilitated diffusion of oxygen. Myoglobin is frequently referred to as having an "instant binding tenacity" to oxygen given its hyperbolic oxygen dissociation curve. Different organisms are able to hold their breaths longer due to high concentrations of myoglobin in their muscle cells. Myoglobin is responsible for the pigments that make meat red. The color of the meat is partly determined by the charge of the iron atom in myoglobin and the oxygen attached to it. Myoglobin is found in Type I muscle, Type II A and Type II B, but it is mostly deemed that myoglobin is not found in smooth muscle.

Uteroglobin (SCGB1A1) which belongs to the Secretoglobin (SCGBs) superfamily, is a multifunctional protein that exerts anti-inflammatory and anti-tumorigenic effects by binding small hydrophobic molecules such as phospholipids and prostaglandins. Uteroglobin is involved in numerous functions including anti-inflammation, inhibition of phospholipase A2 and the sequestering of hydrophobic ligands. SCGB1A1 is expressed by Clara cells, the non-ciliated, non-mucous secretory cells predominant in lung bronchioles, and by other epithelia which communicate with the external environment. On top of sequestering pro-inflammatory mediators and carcinogens, Uteroglobin is implicated in the inhibition of cell migration and invasion, platelet aggregation, and T cell differentiation. SCGB1A1 gene defects are associated with a susceptibility to asthma.

Myoglobin is a member of the globin superfamily and can be found in skeletal and cardiac muscles. It is a haemoprotein that contributs to intracellular oxygen storage and transcellular facilitated diffusion of oxygen. Myoglobin has a single-chain globular structure of 153 amino acids, containing a heme prosthetic group (iron-containing porphyrin) in the core around which the remaining apoprotein folds. Myoglobin has 8 alpha helices and a hydrophobic core. Myoglobin’s molecular weight is 16.7 kDa, and it is the primary oxygen-carrying pigment of muscle tissues. The binding of oxygen in myoglobin is different from the cooperative oxygen binding in hemoglobin, since positive collaboration is a property of multimeric/oligomeric proteins only. Instead, the binding of oxygen by myoglobin is uninfluenced by the oxygen pressure in the surrounding tissue. Myoglobin is frequently referred to as having an "instant binding tenacity" to oxygen given its hyperbolic oxygen dissociation curve. Different organisms are able to hold their breaths longer due to high concentrations of myoglobin in their muscle cells. Myoglobin is responsible for the pigments that make meat red. The color of the meat is partly determined by the charge of the iron atom in myoglobin and the oxygen attached to it. Myoglobin is found in Type I muscle, Type II A and Type II B, but it is mostly deemed that myoglobin is not found in smooth muscle. Myoglobin is discharged from damaged muscle tissue (rhabdomyolysis), which contains very high concentrations of myoglobin. Even though the released myoglobin is filtered by the kidneys, it is toxic to the renal tubular epithelium and thus may cause acute renal failure.

Cytoglobin is a globin protein found in the brain and is mainly utilized in marine mammals. CYGB acts a a protector under conditions of hypoxia. The suggested function of CYGB is the modulation of oxygen and nitric oxide metabolism or scavenging free radicals within a cell.

The mammaglobin gene was first identified using a differential screening approach directed at the isolation of novel, human breast cancer-associated genes. Mammaglobin encodes a 10 kDa glycoprotein and is distantly relaetd to a family of epithelial secretory proteins that includes rat estramustine-binding protein/prostatein and human Clara cell 10 kDa protein (CC10)/uteroglobin. Mammaglobin, a mammary-specific member of the uterglobin family, is known to be overexpressed in human breast cancer. Studies suggest that mammaglobin is one of the first relatively mammary-specific and mammary-sensitive markers (85%). Mammaglobin may be valuable used in a panel with BRST-2 (GCDFP-15) and ER in evaluating tumors of unknown primary sites.
SCGB2A2 (the mammaglobin gene) is located on chromosome 11, at locus 11q13. SCGB2A2 is member of the secretoglobin superfamily of which is a group of small dimeric secreted and sometimes glycosylated proteins. Expressed mainly in mucosa, secretoglobins appear to be involved in cell signalling, immune response, chemotaxis, and might also serve as transporters for steroid hormones in humans.

Uteroglobin (SCGB1A1) which belongs to the Secretoglobin (SCGBs) superfamily, is a multifunctional protein that exerts anti-inflammatory and anti-tumorigenic effects by binding small hydrophobic molecules such as phospholipids and prostaglandins. Uteroglobin is involved in numerous functions including anti-inflammation, inhibition of phospholipase A2 and the sequestering of hydrophobic ligands. SCGB1A1 is expressed by Clara cells, the non-ciliated, non-mucous secretory cells predominant in lung bronchioles, and by other epithelia which communicate with the external environment. On top of sequestering pro-inflammatory mediators and carcinogens, Uteroglobin is implicated in the inhibition of cell migration and invasion, platelet aggregation, and T cell differentiation. SCGB1A1 gene defects are associated with a susceptibility to asthma.

HBsAg is the surface antigenof the Hepatitis-B-Virus (HBV). The capsidof a virus has different surface proteins from the rest of the virus. The antigen is a protein that binds specifically on one of these surface proteins. It is commonly referred to as the Australian Antigen.

Alpha-hemoglobin stabilizing protein (AHSP) is an erythroid-specific protein that acts as a chaperone to prevent the aggregation of A-hemoglobin during normal erythroid cell development. AHSP specifically protects free A-hemoglobin from precipitation in live cells and in solution. AHSP is expected to modulate pathological states of alpha-hemoglobin excess such as beta-thalassemia. Furthermore, AHSP promotes alpha globin chain stability in human erythropoiesis. In addition, the AHSP stabilizes the alpha-Hb chain, thus avoiding its precipitation and its ability to generate ROS, which is implicated in cell death. AHSP is expressed in blood and bone marrow. AHSP subunit is a monomer, it forms a heterodimer with free alpha-hemoglobin. On the other hand, AHSP does not bind beta-hemoglobin nor alpha2beta2 hemoglobin A. AHSP is downregulated in TSEs (transmissible spongiform encephalopathies).

Thyroglobulin (TG) represents one of the main autoantigenic targets in autoimmune thyroid disease of humans. TG is a large globular dimeric glycoprotein with a total molecular weight of 660 kDa, which occupies a key precursor role in the biosynthesis of the thyroid hormones. Approximately 75% of the total protein content of the thyroid follicle consists of TG. The thyroid gland uses the Thyroglobulin in order to produce the thyroid hormones thyroxine (T4) and triiodothyronine (T3). Thyroglobulin is produced by the thyroid epithelial cells (thyrocytes) which form spherical follicles. Thyroglobulin is subsequently secreted and stored in the follicular lumen.
Patients with Hashimoto's thyroiditis or Graves' disease, frequently develop antibodies against Thyroglobulin. Tg-specific antibodies help in the diagnosis of the above diseases, however they also may be present in apparently healthy euthyroid individuals. Blood Thyroglobulin levels can be used as a tumor marker for certain kinds of thyroid cancer, and the may also be elevated in cases of Graves' disease.

Neuroglobin, 151 amino acid residue protein, mainly expressed in vertebrate brain and retina, is a recently identified member of the globin superfamily. Augmenting O (2) supply, neuroglobin promotes survival of neurons upon hypoxic injury, potentially limiting brain damage. Moreover, neuroglobin may be a novel oxidative stress-responsive sensor for signal transduction in the brain. Neuroglobin expression is increased by neuronal hypoxia in vitro and focal cerebral ischemia in vivo, and neuronal survival after hypoxia is reduced by inhibiting neuroglobin expression with an antisense oligodeoxynucleotide and enhanced by neuroglobin overexpression.