Neutrophil Inhibitory Factor (NIF)

Specification

• Cat#: THP-0240
• Product Name: Neutrophil Inhibitory Factor (NIF)
• Description: Neutrophil inhibitory factor (NIF) of the dog hookworm, Ancylostoma caninum, is a 41 kDa secreted glycoprotein that is thought to allow the hookworm to evade the innate immune defenses of the host.
• Species: A. caninum
• Molecular Weight: Predicted Molecular Mass: 30 kDa SDS-PAGE: 55-65 kDa, reducing conditions
• Source: Mouse myeloma cell line
• Introduction: NIF interacts with the leukocyte integrin alpha M beta 2 (CD11b/CD18, also called Mac-1), thus inhibiting mammalian neutrophil adhesion to endothelium. The A. caninum NIF cDNA encodes 257 amino acids (aa) including a 17 aa signal sequence and a 240 aa mature protein with 10 cysteine residues and 7 potential N-linked glycosylation sites. Incubation of mammalian neutrophils with NIF does not appear to be toxic, but does result in rapid, cation‑dependent, reversible inhibition of alpha M beta 2-mediated adhesion and degranulation. The NIF binding site within the alpha M beta 2 I-domain interferes with activation‑dependent adhesion sites of ligands including ICAM-1/CD54, complement component C3b, and fibrinogen. In mouse or guinea pig inflammatory lung injury models, administration of NIF prevented neutrophil-dependent vascular injury.
• Purity: >95%, by SDS-PAGE under reducing conditions and visualized by silver stain
• Biological Activity: Measured by its ability to inhibit the adhesion of PMA-activated human neutrophils. The ED50 for this effect is 0.1-0.4 μg/mL. Also measured by its ability to bind Recombinant Human Integrin alpha M beta 2 in a functional ELISA.
• Reconstitution: Reconstitute at 200 μg/mL in PBS.
• Application: NIF interacts with the leukocyte integrin alpha M beta 2 (CD11b/CD18, also called Mac-1), thus inhibiting mammalian neutrophil adhesion to endothelium.