recombinant mycobacterium tuberculosis fusion protein (EC)

**Recombinant Mycobacterium tuberculosis fusion protein (EC)** is a diagnostic skin test reagent developed by **Anhui Zhifei Longcom Biopharmaceutical** for the detection of *Mycobacterium tuberculosis* infection. The product is a recombinant fusion protein expressed in Chinese Hamster Ovary (CHO) cells, consisting of two highly specific antigens: **Early Secretory Antigenic Target 6 (ESAT-6)** and **Culture Filtrate Protein 10 (CFP-10)**. These antigens are encoded within the region of difference 1 (RD1) of the *M. tuberculosis* genome, which is absent in all *Mycobacterium bovis* BCG strains and most non-tuberculous mycobacteria (NTM). Consequently, the EC skin test can accurately differentiate between TB infection and BCG vaccination, addressing a major limitation of the traditional Tuberculin Purified Protein Derivative (PPD) test. Administered via **intradermal injection**, the protein triggers a delayed-type hypersensitivity (DTH) reaction in sensitized individuals, which is measured by the diameter of induration after 48 to 72 hours. It was approved by the China National Medical Products Administration (NMPA) in 2020 and is marketed under the brand name **Yika**.

Brand names

YikaEkubai

Other names

EC skin testRecombinant Mycobacterium tuberculosis fusion protein (EC) (CHO Cell)ESAT-6/CFP-10 fusion protein