Recombinant Protein

The transforming growth factor-β (TGF-β) superfamily comprises over 30 members, including TGF-β, Activin, Inhibin, bone morphogenetic proteins (BMPs), and growth differentiation factors (GDFs). It can be roughly divided into two subfamilies: the TGF-β/Activin/Nodal subfamily and the BMP/GDF/MIS (Müllerian inhibiting substrate) subfamily.

The growth hormone (GH) family comprises pituitary GH, placental lactogens (PLs), and prolactin (PRL)—evolutionarily related hormones that signal through single-pass, class-I cytokine receptors coupled to JAK2-STAT, MAPK, and PI3K cascades.

The first discovery of fetuin-A dates back to 1944 by K. Pedersen in the blood of a fetal calf (hence the name “fetuin”) . Many years later, the independent studies by J.F. Heremans and K. Schmid with W. Burgi in 1960 and 1961, respectively, purified fetuin-A in humans, and hence it is now also known as α2-Heremans-Schmid glycoprotein (AHSG) in recognition of the discoverers.

Transferrin (TRF) is an important glycoprotein in human plasma, mainly synthesized in the liver. It is composed of 679 amino acid residues, with glycose accounting for about 6%. It has two highly homologous domains, the N - terminal and C - terminal. Each domain has a Fe³⁺ binding site and can reversibly bind two Fe³⁺.

The tumor necrosis factor superfamily (TNFSF) is a group of proteins that play a wide and important role in biology. Currently, 19 ligands have been identified in this family, such as TNF-α, TNF-β, CD40L, FasL, TRAIL, RANKL, etc., and 29 receptors correspond to them.

The colony-stimulating factor (CSF) family comprises soluble glycoproteins that govern the survival, proliferation and lineage-specific differentiation of hematopoietic progenitors while activating mature blood cells.

The interferon (IFN) family comprises three classes: type I (IFN-α/β/κ/ε/ω), type II (IFN-γ) and type III (IFN-λ1/2/3).

The vascular endothelial growth factor (VEGF) family comprises five secreted homodimeric glycoproteins—VEGF-A, VEGF-B, VEGF-C, VEGF-D and placental growth factor (PlGF)—that selectively bind to VEGFR-1, -2, -3 and the co-receptors neuropilin-1/2, thereby orchestrating angiogenesis, lymphangiogenesis and vascular permeability.

The Transforming Growth Factor (TGF) family comprises a group of structurally related cytokines, including TGF-βs, bone morphogenetic proteins (BMPs), activins, and inhibins, which play essential roles in embryogenesis, immune regulation, tissue repair, and fibrosis. These proteins signal through heteromeric complexes of type I and type II serine/threonine kinase receptors, leading to the activation of Smad-dependent intracellular pathways.

The Fibroblast Growth Factor (FGF) family comprises a group of structurally related signaling proteins that play crucial roles in embryonic development, cell proliferation, differentiation, migration, angiogenesis, tissue repair, and metabolic regulation. In humans, the FGF family includes 18 canonical members (FGF1–FGF10 and FGF16–FGF23), which are classified into six subfamilies based on sequence homology and functional characteristics.