Method for producing porcine alpha-interferon

Abstract

The invention relates to a method for producing porcine alpha-interferon, and belongs to the field of the treatment of porcine infection diseases. The invention mainly provides a method for secreting, separating and purifying interferon simply, and aims to simplify a production process, reduce production cost and obtain a recombinant porcine alpha-interferon product with high activity and high stability. The production method comprises the following steps of: producing interferon by using a mixture of methanol; purifying the interferon by multiple-effect ultrafiltration; and making ultrafiltration membranes with different molecular weight cutoff according to the molecular weight of the interferon into a filter, and filtering, so that impure protein and impurities of which the molecular weight is greater than that of the interferon and foreign protein, inorganic salt and water of which the molecular weight is smaller than that of the interferon in a fermentation liquor are removed, and only the interferon and little water are reserved; and freezing and drying to obtain an interferon finished product which is high in purity, activity and stability.

Description

technical field [0001] The invention belongs to the field of treating porcine infectious diseases, and mainly provides an efficient and simple interferon secretion, separation and purification method. Background technique [0002] Interferon was first divided into type Ⅰ and type Ⅱ. Type Ⅰ was once called leukocyte interferon, and type Ⅱ was once called fibroblast interferon. Later, it was found that there are two components in type I interferon. Although they share receptor components, the structure of the two is different and the immunogenicity is completely different, so type I is divided into two types: α and β. Among them, IFN-α is a family of 20 structurally related polypeptides with a molecular weight of about 18KDa, each encoded by an independent gene; IFN-β is a single gene product, a glycoprotein with a molecular weight of 20KDa. Later, type II was designated as γ type. IFN-γ is a glycoprotein composed of subunits of about 21-24KDa in the form of homologous double...

AI Technical Summary

Problems solved by technology

There are following deficiencies in cell crushing: first, the cost is high and the operation is complicated; second, the cell crushing process has a certain effect on interferon, which affects the activity and stability of interferon; Miscellaneous proteins and other impurities are mixed in interferon and are difficult to separate, which reduces the purity and biological activity of interferon products

If Escherichia coli is used as the expression system, the destruction of the bacteria will cause the endotoxin to be mixed in the interferon, which will pose a certain risk to the safety of the drug

If the interferon is recovered from the fermentation broth, the salting-out method is usually adopted, and the salting-out method has the following disadvantages: one is that the salting-out method has no selectivity, and miscellaneous proteins will also be precipitated and mixed in the interferon, making the interferon purity The second is that the salting-out method has a certain impact on the activity of interferon, and some interferon loses its activity due to the destruction of the structure during the precipitation process.