上集提及自90年代起,科學家便開始著手研究利用mRNA的方式試圖在老鼠身上製造對應的蛋白質。站在免疫細胞的角度來看,外來的mRNA終歸是外來之物,並非身體自然產生形成,故此必須鏟除。749Please respect copyright.PENANAKlfIGDp96C749Please respect copyright.PENANAKk9Ay5yCYN
749Please respect copyright.PENANAsRMC0E145m
而在消滅外物的過程中,一系列的免疫反應亦將會啟動。正因如此,若然想將此mRNA技術套用在人類身上的話,科學家必須想辦法使外來的mRNA免受免疫細胞消滅,同時亦需壓抑免疫反應的產生。749Please respect copyright.PENANA7tIVXCR8G0
749Please respect copyright.PENANAswKZvBPUG0
這樣才能使mRNA能順利進入預想的目的地(身體細胞) ,以及減低對身體細胞不必要的負荷產生。749Please respect copyright.PENANAdIFAmbyXdy
749Please respect copyright.PENANAeuasoPnFtl
(圖2)在科學家尋找辦法其間,他們受到一道非常重要的研究啟發。749Please respect copyright.PENANAJVp5AE3Ayv749Please respect copyright.PENANAgBXt2vbuqZ
749Please respect copyright.PENANA8eJ3itMkJ4
對比哺乳動物的DNA,細菌的DNA在人體裡會產生更強烈的免疫反應。749Please respect copyright.PENANAxoRfWWHkv2
尋尋覓覓,科學家們發現,形成此現象的其中一因由是出於哺乳動物的DNA基因排組中,在C及G密集區域裡頻繁出現名為methylation的改造;749Please respect copyright.PENANAgSUPamPW8S
細菌的DNA並沒有頻繁出現這種改造,因此更容易觸發人體的免疫系統反應。749Please respect copyright.PENANAQs3Hwqsw5l
749Please respect copyright.PENANACYuB3xsAex
(圖3)其後,科學家們發現RNA跟DNA一樣,有著不同形形式式的改造,而個別的改造亦有著躲避免疫系統追捕的功能。749Please respect copyright.PENANAGVHOCyaHVr749Please respect copyright.PENANAYed1eWF0J2
749Please respect copyright.PENANAmbhAKyaFzK
更甚的是,不同款式病毒的RNA,其改造結構的出現比普通細胞出現得更為頻繁且為獨特,這亦使科學家們更為堅信,改造mRNA的結構將可成為壓抑產生免疫反應的其中一手段。749Please respect copyright.PENANAc0zm5ITuMo
749Please respect copyright.PENANAhRkN8RUdso
(圖4)積累多年來的研究成果,現時武肺輝瑞mRNA疫苗的mRNA正有著名為N1-methylpseudouridine (m1Ψ)的結構改造,這不但能大大減低我們體內對mRNA所產生的免疫系統反應,同時亦有助mRNA在我們細胞內產生武肺S蛋白質,繼而讓免疫系統辨認及製作對應的抗體。749Please respect copyright.PENANA1vtrnd6AVF
749Please respect copyright.PENANAbN2sX8SRsV
749Please respect copyright.PENANApt0xAheZhs
749Please respect copyright.PENANA8UffL1uUPH
749Please respect copyright.PENANAk5v87tgYGM
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。749Please respect copyright.PENANA5yI6OvdLi7
749Please respect copyright.PENANA3oNlaAMzvu
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/toc749Please respect copyright.PENANAHDCsPhkofL
749Please respect copyright.PENANAelq6WywLcX
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。749Please respect copyright.PENANAZvrTxOsPq6
749Please respect copyright.PENANAnuUlkfuAeU
Link:749Please respect copyright.PENANAIr63MtQAjL
https://www.penana.com/user/27349/%E8%96%AF%E4%BB%94%E8%81%9E%E8%8C%B1%E8%8E%89/portfolio749Please respect copyright.PENANAC2dCfLDAZg
749Please respect copyright.PENANAG3hz6vB9IX
749Please respect copyright.PENANAzrBOpmdPGI
除非Facebook及IG重開侵侵的account,否則我的IG將不會再作更新,只會寄居本土LIHKG及Penana。749Please respect copyright.PENANAhLQLV7eEO6
749Please respect copyright.PENANAa48v5Ygolm
Ref1:https://pubs.acs.org/doi/10.1021/acscentsci.1c00197749Please respect copyright.PENANA6iSDqB1CLU
Ref2:https://www.cell.com/immunity/fulltext/S1074-7613(05)00211-6749Please respect copyright.PENANAJbzgzuF5cm
Ref3:https://www.sciencedirect.com/science/article/abs/pii/S0168365915300948?via%3Dihub749Please respect copyright.PENANA1b1vFtWcNG