IFN-alpha 4/IFNA4 Protein, Human (sf9, His)

IFN-alpha 4 (IFNA4), belongs to type I interferon family, is produced by macrophages with antiviral activities^[1]. IFN-alpha 4/IFNA4 Protein, Human (sf9, His) contains 189 a.a. (M1-D189), produced in Sf9 insect cells cells with a C-terminal His-tag.

IFN-alpha 4 (IFNA4; IFN-α4), belongs to the alpha/beta interferon (IFN) family, is produced by the macrophages with antiviral activities. Interferon (IFN) is originally identified as a substance ‘interfering’ with viral replication in vitro. IFN-α/β and related molecules are classified as type I IFNs, as for the other two types of type II IFN (IFN-γ) and type III IFNs (IFN-λ), respectively^[1].
Interferon alpha (IFNa) shows significant biological activity in various cancers, paticularly haematological malignancies such as hairy cell leukaemia and chronic myelogenous leukaemia^[2].
IFN-alpha 4 is the subtypes dominates in IFN-alpha, whose the response with IFNA5, IFNA7, and IFNA14 accounting for up to 85% of the subtypes expressed by Peripheral blood mononuclear cells (PBMCs)^[3].
IFN-alpha 4 is promoted by interferon (IFN) regulatory factors (IRFs), especially IRF-1 and IRF-7^[5][6]. And it exhibits function by inhibiting virus RNA replication and enhances human natural killer cytotoxicity against virus^[4][7].
As for a wildly use of IFN in animal model, the sequence of amino acids in IFNA4 protein of human is very different from mouse (57.07%) and rat (57.98), respectively.

IFN-alpha 4 exerts function by enhancing human natural killer cytotoxicity in a dose-dependent manner^[4].
IFN-alpha 4 is exclusively activated by IRF-7 and not by IRF-3 in human embryonic kidney 293 cells. IRF-7 is induced by IFN, lipopolysaccharide, and virus infection which has been first described to bind and repress the Qp promoter region of the Epstein-Barr virus (EBV) EBNA-1 gene^[6].
IFN-alpha 4 variant results in significantly decrease of the suppressive effects on HCV RNA replication in HuH-7 cells^[7].

Human

Sf9 insect cells

C-His

P05014 (C24-D189)

3441  [NCBI]

Approximately 20 kDa

Greater than 88% as determined by reducing SDS-PAGE

<1 EU/μg, determined by LAL method.

• [1]. Zhang SY, et al. Inborn errors of interferon (IFN)-mediated immunity in humans: insights into the respective roles of IFN-alpha/beta, IFN-gamma, and IFN-lambda in host defense. Immunol Rev. 2008 Dec;226:29-40.  [Content Brief]

  [2]. Raj NB, et al. Identification of a novel virus-responsive sequence in the promoter of murine interferon-alpha genes. J Biol Chem. 1991 Jun 15;266(17):11360-5.  [Content Brief]

  [3]. Li Y, et al. Expression Pattern of Individual IFNA Subtypes in Chronic HIV Infection. J Interferon Cytokine Res. 2017 Dec;37(12):541-549.  [Content Brief]

  [4]. Verhagen A, et al. Comparison of augmentation of human natural killer cell cytotoxicity by interferon-alpha subtypes. Nat Immun Cell Growth Regul. 1990;9(5):325-33.  [Content Brief]

  [5]. Au WC, et al. Identification of a member of the interferon regulatory factor family that binds to the interferon-stimulated response element and activates expression of interferon-induced genes. Proc Natl Acad Sci U S A. 1995 Dec 5;92(25):11657-61.  [Content Brief]

  [6]. Lin R, et al. Selective DNA binding and association with the CREB binding protein coactivator contribute to differential activation of alpha/beta interferon genes by interferon regulatory factors 3 and 7. Mol Cell Biol. 2000 Sep;20(17):6342-53.  [Content Brief]

  [7]. Xiao CX, et al. Exome sequencing identifies novel compound heterozygous IFNA4 and IFNA10 mutations as a cause of impaired function in Crohn's disease patients. Sci Rep. 2015 May 22;5:10514.  [Content Brief]