至今中國總共有三間生物公司的疫苗踏入Phase3狀態,包括為Cansino、Sinovac及Sinopharm。792Please respect copyright.PENANAo4l00pG7AH
792Please respect copyright.PENANADVA9l2dIsD
其中Sinovac (Phase 3地點:巴西)及國營的Sinopharm(Ref2) (Phase 3地點:阿聯酋)兩間均用上滅活病毒疫苗(Inactivated Virus Vaccine)設計,本文將會就此作深入探討。792Please respect copyright.PENANAbQTTOy31KR792Please respect copyright.PENANAdTWwaVm1aB
792Please respect copyright.PENANAtOQ380u6ic
(圖1)滅活病毒疫苗,顧名思義就是將病毒除去感染能力,當作疫苗之用。792Please respect copyright.PENANAwPmc4M1dwc
792Please respect copyright.PENANA4VNQBKGeb2
下列為Sinovac製作滅活病毒疫苗的扼要流程(Ref3)792Please respect copyright.PENANAnzkC56Hbbx
792Please respect copyright.PENANA6L2s2ryurN
1.從一名進入深切治療部的中國病患肺部體液中抽取病毒。792Please respect copyright.PENANAenoZPz1xYs
792Please respect copyright.PENANAxqjvGAj3Ds
2.經過數輪實驗室細胞的培植,使病毒數量增加。792Please respect copyright.PENANASUaeqbTpGg
792Please respect copyright.PENANAVHSYoYnfif
3.加入化學物消減病毒的感染力和多重過濾,取得弱化的武肺病毒。792Please respect copyright.PENANAU5Ya6RZCo0
792Please respect copyright.PENANAhHlbJW40Ki
4.將其製成可注射的疫苗。792Please respect copyright.PENANABDvOdHoTMn
792Please respect copyright.PENANALmNQ1p8RYj792Please respect copyright.PENANA1bNaGhIuHN
792Please respect copyright.PENANArGijVprn6i
(圖2)將滅活病毒疫苗注射到身體後,身體的免疫細胞便會製作對應弱化病毒的抗體。792Please respect copyright.PENANAdq6WZkiZkj
792Please respect copyright.PENANA8mVFOz5LVM
在繼續講述抗體之前,可先閱覽(圖3)溫故知新一下武肺入侵人體細胞的簡要過程,又或者可以到之前我所寫的文章觀看略為詳細的版本。792Please respect copyright.PENANAw9STKPKeQg
https://www.penana.com/article/466568792Please respect copyright.PENANAz7SDeafgv5
792Please respect copyright.PENANAPlPLeG6xj5792Please respect copyright.PENANAUXTiCa0D4Q
792Please respect copyright.PENANAmAnBDEAfGt
792Please respect copyright.PENANASOSPxu40ZR
792Please respect copyright.PENANACYVpG6b5m9
792Please respect copyright.PENANADUK0OR3adM792Please respect copyright.PENANAvLLaDgsmQX
792Please respect copyright.PENANA9dtwQE9YLk
(圖4)抗體(Antibody)頂多只能阻礙病毒進入細胞或者指示其他免疫細胞前來清滅病毒,並無獨立能力清滅病毒。792Please respect copyright.PENANAfGYddDXW3l
792Please respect copyright.PENANA9D2U5n0CIH
而能夠阻礙病毒進入細胞的抗體,我們將稱之為Neutralizing Antibody,而圖中已列出其中的兩款機制。792Please respect copyright.PENANAi1B2nWoWga
792Please respect copyright.PENANADHACgs5J6J
1.抗體與病毒的S protein合併,792Please respect copyright.PENANAApwNdwzljN
防止條件1的達成。792Please respect copyright.PENANAbIl0edQVSz
792Please respect copyright.PENANAqECgopVIdv
2.抗體與病毒其他位置合併,792Please respect copyright.PENANAPNoYRVCRSB
防止條件3的達成。792Please respect copyright.PENANAV8fHIeumgb
792Please respect copyright.PENANAs9560pOjP8792Please respect copyright.PENANADciXOM5OAo
792Please respect copyright.PENANACxDSYXdeyj
(圖5)用上滅活病毒疫苗的話,抗體的製作便會針對病毒的各個位置而進行。792Please respect copyright.PENANAmGmMud9VVh
基於並非所有抗體也能夠拼合在病毒的關鍵位置,不能夠阻礙病毒進入細胞的抗體,我們將稱之為Non-Neutralizing Antibody。792Please respect copyright.PENANA3UhVWHyc5m
792Please respect copyright.PENANABEG2GGgtZE
不過,就算是Non-Neutralizing Antibody,它亦能有能力標示病毒,指引其他免疫細胞前來清滅病毒。792Please respect copyright.PENANARNJWjcEqRJ
792Please respect copyright.PENANANfGSGeWlhf
792Please respect copyright.PENANAraSDDv44ED792Please respect copyright.PENANAPbVcOTO4J4
792Please respect copyright.PENANAiqQTUXsarE
(圖6)Non-Neutralizing Antibody的出現,將會引伸出一個名為Antibody Dependent Enhancement(ADE)的重要問題;792Please respect copyright.PENANAtLlaIql6wG
簡單來說,就是抗體適得其反地協助病毒入侵人體細胞。792Please respect copyright.PENANAWO2xfx3k8R
792Please respect copyright.PENANAh97ExR5d9k
免疫細胞的表面上,有著接收器識辨抗體的某個區域。792Please respect copyright.PENANAlu1lM0Nv39
792Please respect copyright.PENANAsoCNdgxaGq
但若果有過多Non-Neutralizing Antibody黏在病毒裡頭的話,病毒就有機會可以無視之前那3條法則,不需要經過ACE2,而是透過免疫細胞的表面上識辨抗體的接收器進入細胞。792Please respect copyright.PENANAqyZKObj9L0
792Please respect copyright.PENANAoblTR9CmJX
換句話說,抗體在這情況下變相成為幫兇或者25仔,輔助病毒進入細胞,這現象我們稱之為ADE。792Please respect copyright.PENANAY54DDOljhY
792Please respect copyright.PENANAy0mFOwbpdn792Please respect copyright.PENANATvVRPYRu7a
792Please respect copyright.PENANA2Jj4aL1ksW
(圖7)武肺病毒進入細胞後,需要切割S protein才能夠開始進行繁殖工作。792Please respect copyright.PENANAd5RFVN5dKI
所以就算有Non-Neutralizing antibody做25仔,如果病毒幸運地有Neutralizing antibody保護S protein免受切割的話,病毒依舊無法作惡。792Please respect copyright.PENANAXQ3ij8FJwp
792Please respect copyright.PENANAkzk016TdqI
但若果無Neutralizing antibody保護的話,病毒就會利用免疫細胞作為寄主,避開一切免疫機制,大量製造病毒。792Please respect copyright.PENANA3ilqiJwwXT
情形就好像本身理應維護法紀的警察,突然之間搖身一變成為罪惡的溫床,窩藏及協助罪犯(病毒)滋生,導致情況一發不可收拾。792Please respect copyright.PENANAacefIi8hVu
792Please respect copyright.PENANASzqev8a58L792Please respect copyright.PENANA6d1GT53muT
792Please respect copyright.PENANAHwWdelbACL
(圖8)ADE這現象,科學家一直以來均有記錄及研究。(Ref4)792Please respect copyright.PENANAKDYlt5czlt
以登革熱為例,病人染上登革熱病毒(Dengue Virus)的話,身體便會製造登革熱病毒抗體。792Please respect copyright.PENANAIemgFMyVfh
但基於登革熱病毒與寨卡病毒(Zika Virus)有頗為相似的地方,某部份的登革熱病毒抗體「幸運地」便成為寨卡病毒的Non-Neutralizing Antibody,透過ADE幫忙寨卡病毒入侵人體。792Please respect copyright.PENANAYZmzAaT5xd
792Please respect copyright.PENANAY9C3SIjSTt
亦即是說,擁有登革熱病毒抗體的人反而更有機會受到寨卡病毒入侵。792Please respect copyright.PENANAAZaQeOoW5Q
792Please respect copyright.PENANA2rWBYU1lAJ792Please respect copyright.PENANAnjptfOdzHZ
792Please respect copyright.PENANASVB4X7Dgfu
(圖9)有研究指出,03年SARS病毒亦會依靠未曾上市的疫苗所產生出的Non-Neutralizing Antibody,不需經過ACE2便能入侵免疫細胞。(Ref5)792Please respect copyright.PENANAdJYzOcjAi5
792Please respect copyright.PENANAP3GbjnxHCn
武肺會否出現同樣現象,暫時尚未清楚。792Please respect copyright.PENANAVoMZEqN7PB
792Please respect copyright.PENANAmDlMRaH4p3
只不過各國進行Phase3中的疫苗,大多也是針對著武肺病毒S protein位置而設計,故此出現Non-Neutralizing antibody將會比用上整個武肺病毒而作為疫苗設計的那兩間公司為低,ADE的機率亦相對減少。792Please respect copyright.PENANA5sICyFSW1A
792Please respect copyright.PENANArqv7ksM113
當然,另一方面來看,中國那兩間公司因為用上整個武肺病毒來設計疫苗,理論上所產生的抗體數量及濃度亦會為高,抵抗的效果亦會相對顯著,但ADE的機率出現亦會相對為高。792Please respect copyright.PENANAl2Env32uq1
792Please respect copyright.PENANAldEuxd4hR7
792Please respect copyright.PENANA0w9Z16xqlb
美國Moderna已表示Phase3的報告將會探討ADE的可能,但願中國Sinovac及國營Sinopharm的Phase3報告,也會在ADE方面進行深入探討吧!792Please respect copyright.PENANAO5pawa9tLI
792Please respect copyright.PENANApROeF2yEnL
如果想我快啲出文的話,請入去Penana網站科普專欄–薯不揀單俾一個like以及Bookmark,這對我非常之重要。792Please respect copyright.PENANA12SZFnBzKF
792Please respect copyright.PENANAfAVF4xTWOX
Link: https://www.penana.com/story/66244/%E7%A7%91%E6%99%AE%E5%B0%88%E6%AC%84-%E8%96%AF%E4%B8%8D%E6%8F%80%E5%96%AE/toc792Please respect copyright.PENANAupADadlY4g
792Please respect copyright.PENANANuMFMr0rDZ
同時亦可以在Penana網站裡按「買一嚿/半嚿薯仔」,以課金的方式推動我繼續搜羅資料寫文,多謝。792Please respect copyright.PENANA9QIKVSr6KA
792Please respect copyright.PENANAB6GB0jcBWk
Link:792Please respect copyright.PENANAQuJBzhRjxe
https://www.penana.com/user/27349/%E8%96%AF%E4%BB%94%E8%81%9E%E8%8C%B1%E8%8E%89/portfolio792Please respect copyright.PENANA24QnMjjSHM
792Please respect copyright.PENANAQ6R4TP5zZA
792Please respect copyright.PENANAxBwckT91pq
有興趣接收科普資訊的話,歡迎follow IG: potatopigtongue。792Please respect copyright.PENANA59A1Dquejc
792Please respect copyright.PENANAUwi6ocgYrC
792Please respect copyright.PENANASoBdR4m0xT
Ref2:https://jamanetwork.com/journals/jama/fullarticle/2769612?fbclid=IwAR0sp9eU5V9FOzuLjz6ERw6LRFm-1yx3MJt1OEgqBDQKW1GA5mQeIIi5J7E792Please respect copyright.PENANAkodRzaJ7ll
Ref3:https://science.sciencemag.org/content/369/6499/77?fbclid=IwAR29zOO06gVsQAC2jLU2uMJi-qcYbniz108Y4kcaWOr1iNuQyVM3jCFMHa4792Please respect copyright.PENANAtV4xZDD91U
Ref4:https://www.nature.com/articles/s41586-020-2538-8.pdf792Please respect copyright.PENANA6mF6RNVse1
Ref5:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7115629/792Please respect copyright.PENANAozj7JlvM43