Ekspresi Protein Resuscitation promoting factor-D Mycobacterium tuberculosis pada sel CHO-K1 secara in-vitro

  • Wahyu Agung Pratama
  • Andriansjah Rukmana
  • Fithriyah Sjatha
Keywords: Resuscitation promoting factor-D, Mycobacterium tuberculosis, sel CHO-K1, transfeksi, immunostaining

Abstract

Abstrak Protein Resuscitation promoting factor–D (Rpf-D) merupakan protein transmembran dari Mycobacterium tuberculosis dan dieskpresikan pada fase reaktivasi infeksi laten menjadi aktif. Protein Rpf-D tersusun atas 154 asam amino berukuran 16 kDa yang dikode oleh 456 basa dari famili gen-Rpf. Pada studi sebelumnya, kami telah berhasil mengklona gen rpfD dari Mycobacterium tuberculosis strain Beijing kedalam plasmid pcDNA3.1, dikenal sebagai pcDNA3.1-rpfD. Dalam studi ini, kami mentransfeksi sel mamalia CHO-K1 dengan plasmid rekombinan pcDNA3.1-rpfD dan dilanjutkan dengan pewarnaan imunologis menggunakan serum mencit yang telah diimunisasi dengan pcDNA3.1-rpfD sebagai vaksin DNA. Hasil pewarnaan menunjukkan bahwa protein RpfD mampu diekspresikan pada sel mamalia. Selain itu, protein rekombinan yang diekspresikan ini terbukti bersifat imunogenik dan mampu menginduksi respon imun humoral pada hewan uji mencit Balb/C berupa IgG1, IgG2a, IgG2b dan IgG3. Hasil penelitian ini menunjukan potensi pemanfaatan protein rekombinan RpfD untuk penelitian lanjutan pengembangan vaksin ataupun uji diagnosis tuberkulosis.

Kata kunci: Resuscitation promoting factor-D, Mycobacterium tuberculosis, sel CHO-K1, transfeksi, immunostaining

Abstract Resuscitation promoting factor-D (Rpf-D) protein is known as a component of Mycobacterium tuberculosis cell wall which highly expressed in reactivation state of latent tuberculosis to turn in to an active infection. Rpf-D protein is a small protein consist of 154 amino acids encoded by 465 nucleotides in Rpf-gene family and having 16 kDa in size. In our previous study, we had successfully cloned Rpf-D gene of Mycobacterium tuberculosis Beijing strain into pcDNA3.1 plasmid expression system, which named as pcDNA3.1-rpfD later on. In this study, we transfect pcDNA3.1-rpfD into CHO-K1 mammalian cell line followed by immunostaining using mice sera immunized with pcDNA3.1-rpfD as DNA vaccine. Our result shows that our recombinant pcDNA3.1-rpfD construct can express recombinant RpfD protein in mammalian cells. On the other hand, this expressed recombinant protein has been proven to be immunogenic and able to induce a humoral immune response in Balb/C mice especially IgG1, IgG2a, IgG2b, and IgG3. Our study has shown the potency of recombinant RpfD protein which can be further developed as vaccine or diagnostic approach for tuberculosis.

Keywords: Resuscitation promoting factor-D, Mycobacterium tuberculosis, CHO-K1 cells, transfection, immunostaining

Published
2020-09-29
Section
Articles