a-b and -a chains

Expression system: E. coli
Length: 1-192, Full Length
Activity: Not Tested

Immunoglobulin Kappa is constant region of immunoglobulin light chains. Immunoglobulins, also known as antibodies, are membrane-bound or secreted glycoproteins produced by B lymphocytes. In the recognition phase of humoral immunity, the membrane-bound immunoglobulins serve as receptors which, upon binding of a specific antigen, trigger the clonal expansion and differentiation of B lymphocytes into immunoglobulins-secreting plasma cells. Secreted immunoglobulins mediate the effector phase of humoral immunity, which results in the elimination of bound antigens. The antigen binding site is formed by the variable domain of one heavy chain, together with that of its associated light chain. Thus, each immunoglobulin has two antigen binding sites with remarkable affinity for a particular antigen. The variable domains are assembled by a process called V-(D)-J rearrangement and can then be subjected to somatic hypermutations which, after exposure to antigen and selection, allow affinity maturation for a particular antigen.

Expression system: HEK293 Cells
Length: 23­124, Partial
Activity: Not Tested

Expression system: E. coli
Length: 193-510, Full Length of Mature Protein
Activity: Not Tested

Expression system: P. pastoris (Yeast)
Length: 34-287, Partial
Activity: Not Tested

As a monomeric immunoglobulin that is predominately involved in the secondary antibody response and the only isotype that can pass through the human placenta, Immunoglobulin G (IgG) is synthesized and secreted by plasma B cells, and constitutes 75% of serum immunoglobulins in humans. IgG antibodies protect the body against the pathogens by agglutination and immobilization, complement activation, toxin neutralization, as well as the antibody-dependent cell-mediated cytotoxicity (ADCC). IgG tetramer contains two heavy chains (50 kDa ) and two light chains (25 kDa) linked by disulfide bonds, that is the two identical halves form the Y-like shape. IgG is digested by pepsin proteolysis into Fab fragment (antigen-binding fragment) and Fc fragment ( crystallizable fragment). IgG1 is most abundant in serum among the four IgG subclasses (IgG1, 2, 3 and 4) and binds to Fc receptors (FcγR ) on phagocytic cells with high affinity. Fc fragment is demonstrated to mediate phagocytosis, trigger inflammation, and target Ig to particular tissues. Protein G or Protein A on the surface of certain Staphylococcal and Streptococcal strains specifically binds with the Fc region of IgGs, and has numerous applications in biotechnology as a reagent for affinity purification. Recombinant IgG Fc Region is suggested to represent a potential anti-inflammatory drug for treatment of human autoimmune diseases.

MASP3 is a member of the MASPs involved in mannan-binding lectin (MBL) complement pathway. The MBL pathway is initiated by the binding of MBL to specific carbohydrate structures found on the surface of a variety of microorganisms. Activation of the complement pathway via MBL is initiated by specific MASPs. Three MASPs have been identified and all have domain structures similar to those of C1r and C1s with a heavy chain (chain A) and a light chain (chain B). Chain A is composed of CUB1, EGF, CUB2, CCP1 and CCP2 while chain B corresponds to the catalytic domain found in many serine proteases. MASP1 and MASP3 are two alternatively spliced products of a single gene, which contain the same A chains but entirely different B chains. Distinct MASPs found in different MBL oligomers may have different biological activities. For example, MASP3, found together with MASP2, downregulates the C4 and C2 cleaving activity of MASP2. The protease activity of MASP3 is first revealed here using rhMASP3CD, which is inhibited by serine protease inhibitors such as Ecotin and AEBSF.

Expression system: E. coli
Length: 1-469, Full Length
Activity: Not Tested

Expression system: Baculovirus Insect Cells
Length: 401-693, Partial
Activity: Not Tested

Alpha-2-HS-glycoprotein (AHSG) is a glycoprotein that is composed of two subunits, the A and B chains, belongs to the Cystatin family of proteases inhibitors. It is highly expressed in embryonic cells and adult hepatocytes, and is expressed to a lesser extent in monocytes macrophages. AHSG is an important circulating inhibitor of calcification in vivo, and is downregulated during the acute-phase response. It is involved in several functions, such as endocytosis, brain development and the formation of bone tissue. In addition, AHSG may influence the resolution of inflammation by modulating the phagocytosis of apoptotic cells by macrophages. ASHG blocks TGF-beta-dependent signaling in osteoblastic cells.

IL15RA is a high-affinity receptor for interleukin-15. Il15ra associates as a heterotrimer with the IL-2 receptor beta and gamma subunits to initiate signal transduction. It can signal both in cis and trans where IL15R from one subset of cells presents IL15 to neighboring IL2RG-expressing cells. Il15ra is expressed in special cells including a wide variety of Tand B cells and non-lymphoid cells.IL-15 is a cytokine that regulates T cell and natural killer cell activation and proliferation. IL-15 binds to the alpha subunit of the IL-15RA with high affinity. IL-15 also binds to the beta and gamma chains of the IL-2 receptor, but not the alpha subunit of the IL2 receptor. IL-15 is structurally and functionally related to IL-2. Both cytokines share some subunits of receptors, allowing them to compete for and negatively regulate each other's activity. The number of CD8+ memory T cells is controlled by a balance between IL-15 and IL-2. Despite their many overlapping functional properties, IL-2 and IL-15 are, in fact, quite distinct players in the immune system. IL-15 is constitutively expressed by a wide variety of cell types and tissues, including monocytes, macrophages and DCs. The enhanced activity of the IL-15N72D:IL-15RαSu Fc complex is likely the result of the increased binding activity of IL-15N72D to IL-15Rβγ c , optimized cytokine trans-presentation by the IL-15RαSu domain, the dimeric nature of the cytokine domain and its increased in vivo half-life compared to IL-15. These findings indicate that this IL-15 superagonist complex could serve as a superior immunostimulatory therapeutic agent.

Immunoglobulin lambda constant region is constant region of immunoglobulin light chains. Immunoglobulins, also known as antibodies, are membrane-bound or secreted glycoproteins produced by B lymphocytes. In the recognition phase of humoral immunity, the membrane-bound immunoglobulins serve as receptors which, upon binding of a specific antigen, trigger the clonal expansion and differentiation of B lymphocytes into immunoglobulins-secreting plasma cells. IGLC2 is 105 amino acids (aa) in length. It contains one Ig-like domain (aa 7-100) and generates a disulfide bond with an IgH chain via Cys104.

INSL4 (Insulin-Like 4) is a Protein Coding gene. An important paralog of this gene is RLN1. INSL4 encodes a precursor that undergoes post-translational cleavage to produce 3 polypeptide chains, A-C, that form tertiary structures composed of either all three chains or just the A and B chains. INSL4 is a member of the insulin family, which includes insulin, IGF-I, IGF-II, relaxin, and INSL3.INSL4 distribution was tissue- and cell-specific. Indeed, INSL4 mRNA was most abundant in syncytiotrophoblast cells. In fetal tissues, INSL4 mRNA was identified in the perichondrium of all four limbs, vertebrae, and ribs. Diseases associated with INSL4 include Placenta Accreta and Chromosome 9P Deletion Syndrome.

Complement Component 1, q subcomponent (C1q) associates with C1r and C1s in order to yield the first component of the serum complement system. Deficiency of C1q has been associated with lupus erythematosus and glomerulonephritis. C1q is composed of 18 polypeptide chains: six A-chains, six B-chains, and six C-chains. Southern blot analysis of chromosomal DNA from vertebrate species demonstrated highest similarity between the C1qB genes, followed by C1qC and finally C1qA. Sequence comparison of C1q from three different species have shown that the B chains have the strongest similarity. C1q was already present at embryonic day 14 (E14) and showed little change in abundance through six weeks postnatal. At E16, C1qB mRNA was present at high abundance in putative microglia macrophages in cortical marginal and intermediate zones, and hippocampal analge.

Lactotransferrin is a member of the transferrin family that transfer iron to the cells and control the level of free iron in the blood and external secretions. Lactotransferrin is a secreted protein and contains two transferrin-like domains. Lactotransferrin can be cleaved into the following four chains: Kaliocin-1, Lactoferroxin-A, Lactoferroxin-B, and Lactoferroxin-C. Lactoferroxin A, Lactoferroxin B, and Lactoferroxin C have opioid antagonist activity. Lactoferroxin A shows preference for mu-receptors, while Lactoferroxin B and Lactoferroxin C have somewhat higher degrees of preference for kappa-receptors than for mu-receptors. LTF has antimicrobial activity (bacteriocide, fungicide) and is part of the innate defense, mainly at mucoses.

IL15RA is a high-affinity receptor for interleukin-15. Il15ra associates as a heterotrimer with the IL-2 receptor beta and gamma subunits to initiate signal transduction. It can signal both in cis and trans where IL15R from one subset of cells presents IL15 to neighboring IL2RG-expressing cells. Il15ra is expressed in special cells including a wide variety of Tand B cells and non-lymphoid cells.IL-15 is a cytokine that regulates T cell and natural killer cell activation and proliferation. IL-15 binds to the alpha subunit of the IL-15RA with high affinity. IL-15 also binds to the beta and gamma chains of the IL-2 receptor, but not the alpha subunit of the IL2 receptor. IL-15 is structurally and functionally related to IL-2. Both cytokines share some subunits of receptors, allowing them to compete for and negatively regulate each other's activity. The number of CD8+ memory T cells is controlled by a balance between IL-15 and IL-2. Despite their many overlapping functional properties, IL-2 and IL-15 are, in fact, quite distinct players in the immune system. IL-15 is constitutively expressed by a wide variety of cell types and tissues, including monocytes, macrophages and DCs.

Expression system: Baculovirus Insect Cells
Length: 1-342, Full Length
Activity: Not Tested

As a monomeric immunoglobulin that is predominately involved in the secondary antibody response and the only isotype that can pass through the human placenta, Immunoglobulin G (IgG) is synthesized and secreted by plasma B cells. IgG antibodies protect the body against the pathogens by agglutination and immobilization, complement activation, toxin neutralization, as well as the antibody-dependent cell-mediated cytotoxicity (ADCC). IgG tetramer contains two heavy chains (50 kDa ) and two light chains (25 kDa) linked by disulfide bonds, that is the two identical halves form the Y-like shape. IgG is digested by pepsin proteolysis into Fab fragment (antigen-binding fragment) and Fc fragment ( crystallizable fragment). IgG1 is most abundant in serum among the four IgG subclasses (IgG1, 2, 3 and 4) and binds to Fc receptors (FcγR ) on phagocytic cells with high affinity.

Carboxypeptidase A1 (CPA1) is secreted as a pancreatic peptidase that comes from the precursor form of inactive procarboxypeptidase. CPA1 comprises a signal peptide, a pro region and a mature chain, and can be activated after cleavage of the pro peptide. It has a free C-terminal carboxyl group, with the preference of residues with aromatic or branched aliphatic side chains. CPA1 cleaves the C-terminal amide or ester bond of peptides and involves in zymogen inhibition. Three different forms of human pancreatic procarboxypeptidase A have been isolated. In contrast to procarboxypeptidase B which was always secreted by the pancreas as a monomer, procarboxypeptidase A occurs as a monomer and or associated to one or two functionally different proteins, such as zymogen E.

Ubiquitin-Conjugating Enzyme Variant 1a (UBE2V1) is a member of the Ubiquitin-conjugating (E2) enzyme family. The E2 catalytic core domain of UBE2V1 lacks an active site cysteine residue, rendering it catalytically inactive on its own. However, in the cytoplasm UBE2V1 is able to form a catalytically active complex with UBE2N Ubc13, which mediates the synthesis Lys63-linked Ubiquitin chains and is required for NF-kappa B activation. UBE2V1 is required for UBE2N (Ubc13) UBE2V1 Complex-dependent Lys63-linked Ubiquitin chain formation. More specifically, UBE2V1 orients the Ubiquitin molecule to favor linkage at Lys63 via a non-covalent interaction with the Ubiquitin molecule. The UBE2V1-UBE2N heterodimer catalyzes the synthesis of non-canonical poly-ubiquitin chains that are linked through Lys63. This type of poly-ubiquitination activates IKK and does not seem to involve protein degradation by the proteasome. UBE2V1 plays a role in the activation of NF-kappa-B mediated by IL1B, TNF, TRAF6, and TRAF2. It mediates transcriptional activation of target genes. UBE2V1 also controls the progress through the cell cycle and differentiation, the error-free DNA repair pathway and contributes to the survival of cells after DNA damage.

Expression system: E. coli
Length: 655-1213, Partial
Activity: Not Tested