독일 연구진 "보톡스" 내성 가능성 발표, 요즘 "2세대" 톡신 "제오민(Xeomin)"이 인기..
보톡스(보톡스R)의 순수한 톡신은 150키로달톤(kDa)에 불과하다.
효과를 나타내는 톡신은 150kDa 로 충분하지만 불필요한 단백질이 함유되어 톡신의 입자당의 무게는 900달톤(kDa)의 제품으로 출시된다.
이런 불필요한 단백질은 우리몸에서 이물질로 인식을 하게되어 항체가 형성되는 경우가 발생하게된다.
이번 독일의 연국진은
보톡스는 불필요한 단백질들이 함유되어 있어 이런 불순물들이 항체를 만들게되러
결국 보톡스를 맞을수록 효과가 떨어지는 내성이 발생하게 되는 확률이 증가된다는 연구를 발표하였다.
또한 보톡스는 톡신의 안정성의 문제로 냉장보관을 해야하는 문제점들이 있지만
2세대 톡신 제오민은 냉장보관이 필요 없다. 그만큼 안정화 되어 있고 불순물이 적은 톡신인것이다.
보톡스는 제오민보다 주사후 주름이 펴지는 발현효과가 느리지만 제오민은 불순물이 적은것뿐 아니라 발현 효과도 아주 빠르다
2세데 보톡스 로 불리우는 독일의 Merz사의 제오민은 불순물을 걸러내서 순수한 톡신 150키로달톤으로 구성된 신세대 톡신이다. 글 김종서성형외과 원장 김종서
기사원문.... Botox less effective the more it is used
Women who regularly get Botox treatments seeking youth are becoming immune to the injection, even forming antibodies to it, a report said.
German researchers published a paper in the Journal of Neural Transmission, saying that one out of 200 Botox patients come to develop antibodies which lead to ineffective results.
More negative results were found among those who took a larger dose of injection than others due to medical reasons such as treating spasms or sweating.
Other scientists from British Medical Journal’s online forum also found that repeated treatment with Botox “triggers an immune response ... which might lead to non-responsiveness to treatment.”
Dr. Kuldeep Minocha of Harley Street’s Absolute Aesthetics Clinic also said his patients became immune to the treatment, particularly those who have gotten the injections for about 10 years. If the patients’ bodies get used to the chemical, Botox gets broken down more quickly, resulting in less effects.
He said that while the reported number of antibodies formed remained relatively small, the actual figure might be much higher since few patients go through close examinations in order to find out the cause of failed treatments.
From news reports http://www.koreaherald.com/view.php?ud=20130429001052 해외논문 자료
해외논문 관련자료 항체형성기전 설명 Llama Antibody Inhibits Botulinum Neruotoxin Ingestion or inhalation of botulinum neurotoxin (BoNT) results in botulism, a severe and frequently fatal disease. Current treatments rely on antitoxins, which, while effective, cannot reverse symptoms once BoNT has entered the neuron. For treatments that can reverse intoxication, interest has focused on developing inhibitors of the enzymatic BoNT light chain (BoNT Lc). Such inhibitors typically mimic substrate and bind in or around the substrate cleavage pocket. To explore the full range of binding sites for serotype A light chain (BoNT/A Lc) inhibitors, we created a library of non-immune llama single-domain VHH (camelid heavy-chain variable region derived from heavy-chain-only antibody) antibodies displayed on the surface of the yeast Saccharomyces cerevisiae. Library selection on BoNT/A Lc yielded 15 yeast-displayed VHH with equilibrium dissociation constants (K(d)) from 230 to 0.03 nM measured by flow cytometry. Eight of 15 VHH inhibited the cleavage of substrate SNAP25 (synaptosome-associated protein of 25,000 Da) by BoNT/A Lc. The most potent VHH (Aa1) had a solution K(d) for BoNT/A Lc of 1.47 x 10(-)(10) M and an IC(50) (50% inhibitory concentration) of 4.7 x 10(-)(10) M and was resistant to heat denaturation and reducing conditions. To understand the mechanism by which Aa1 inhibited catalysis, we solved the X-ray crystal structure of the BoNT/A Lc-Aa1 VHH complex at 2.6 A resolution. The structure reveals that the Aa1 VHH binds in the alpha-exosite of the BoNT/A Lc, far from the active site for catalysis. The study validates the utility of non-immune llama VHH libraries as a source of enzyme inhibitors and identifies the BoNT/A Lc alpha-exosite as a target for inhibitor development.
