Hipótese era de que havia restos de vírus na garganta dos pacientes mesmo após a cura, mas nova explicação envolve integração do Sars-CoV-2 no genoma humano
Fernando Reinach, O Estado de S.Paulo
O método mais sensível para saber se uma pessoa está infectada pelo Sars-CoV-2 consiste em coletar uma amostra da secreção presente na garganta e nas narinas. Em seguida, se usa o PCR para detectar a presença do RNA do vírus na amostra. Se o resultado for positivo, a pessoa está infectada: é o famoso teste de PCR. O problema é que, mesmo após a pessoa estar curada, esse teste continua dando resultados positivos em muitos casos.
Isso ocorre porque fragmentos do RNA do vírus continuam presentes na garganta da pessoa por meses. Mas de onde viriam esses fragmentos se o vírus foi eliminado pelo sistema imune e a pessoa está curada? Até agora a explicação era que mesmo depois da cura sobrariam restos do vírus na garganta. Agora foi descoberto que a explicação é outra.
O genoma do Sars-CoV-2 consiste em uma molécula de RNA recoberta por uma cápsula de onde saem os espinhos que aparecem nas fotos. Após invadir uma célula humana, o RNA presente no vírus é liberado e multiplicado, gerando um número enorme de outras moléculas de RNA que são encapsuladas, se transformando em novas partículas virais. Essa nova geração de vírus é liberada e infecta outras células. É assim que o vírus se espalha pelo corpo.
Faz muitos anos que sabemos que moléculas de RNA presentes no interior de uma célula humana podem ser transformadas em moléculas de DNA e essas moléculas de DNA ocasionalmente podem ser inseridas no DNA da célula hospedeira.
Sabendo disso, os cientistas resolveram investigar se isso acontecia com o RNA do Sars-CoV-2. Para tanto, usaram diversos métodos que consistem em isolar o DNA de células infectadas, sequenciar esse DNA e verificar se pedaços de DNA com sequências do Sars-CoV-2 estão presentes. Não só os cientistas encontraram diversos fragmentos do vírus em diversas regiões do genoma, mas descobriram que as regiões que delimitam os locais da inserção são típicas de um mecanismo que existe em todos nós e que pode transformar moléculas de RNA em DNA e inseri-las no genoma.
Também foi possível demonstrar que esses fragmentos inseridos não são capazes de produzir novas partículas virais (e por isso a pessoa continua curada), mas produzem fragmentos de RNA que podem ser detectados nos testes de PCR.
Essas descobertas demonstram que, em muitas pessoas, o vírus, além de invadir as células e continuar a se espalhar pelo corpo até ser combatido pelo sistema imune, também consegue inserir no genoma das células infectadas pedaços do seu genoma – que permanecem no corpo mesmo após ele estar curado. Esses fragmentos continuam a produzir pedaços de RNA e proteína enquanto essas células que foram infectadas e seus descendentes ficarem em nosso corpo. São esses fragmentos de RNA que são detectados pelo teste de PCR em pessoas já curadas.
Ainda não se sabe se esse fenômeno tem alguma consequência além de gerar testes de PCR positivos, mas os cientistas sugerem que esses fragmentos produzidos podem talvez servir como um estímulo contínuo para o sistema imune ou podem estar envolvidos na presença dos sintomas que, em algumas pessoas, podem durar meses após o término da infecção (a chamada covid longa). Esse fenômeno não é único do Sars-CoV-2, ele já foi detectado em infecções por outros vírus.
O fato é que, após nos curarmos de uma infecção, duas modificações ocorrem em nosso corpo: nosso sistema imune passa a produzir anticorpos e células capazes de combater o vírus e o genoma de parte de nossas células passa a ter fragmentos do genoma do Sars-CoV-2. Essa descoberta pode ter implicações importantes ou ser somente uma explicação de por que algumas pessoas apresentam testes de PCR positivos depois de curadas. É cedo para saber.
MAIS INFORMAÇÕES: REVERSE-TRANSCRIBED SARS-COV-2 RNA CAN INTEGRATE INTO THE GENOME OF CULTURED HUMAN CELLS AND CAN BE EXPRESSED IN PATIENT-DERIVED TISSUES. PROC. NAT. ACAD. SCI. USA https://doi.org/10.1073/pnas.2105968118
* É BIÓLOGO, PHD EM BIOLOGIA CELULAR E MOLECULAR PELA CORNELL UNIVERSITY E AUTOR DE A CHEGADA DO NOVO CORONAVÍRUS NO BRASIL; FOLHA DE LÓTUS, ESCORREGADOR DE MOSQUITO; E A LONGA MARCHA DOS GRILOS CANIBAIS
Hello to every body, it’s my first visit of this blog; this webpage consists of amazing and
actually fine data in support of readers.
Keep honoring us. Ceo of Valeon
I could not refrain from commenting. Perfectly written!
I’ve been exploring for a bit for any high quality articles or
blog posts in this kind of space . Exploring in Yahoo I
eventually stumbled upon this website. Reading this information So i
am happy to express that I’ve a very good uncanny feeling I discovered just what
I needed. I such a lot certainly will make sure to do not forget this web site and provides it a look on a relentless basis.
Also visit my website NeoBio Health Keto Review
It is the best time to make a few plans for the long run and it’s time to be happy.
I’ve read this post and if I could I desire to suggest you few interesting
things or advice. Perhaps you could write subsequent articles relating
to this article. I wish to read even more issues about it!
It’s really a nice and useful piece of information. I’m happy that you just shared
this useful information with us. Please keep us informed like this.
Thank you for sharing.
Have a look at my blog post; Moscatcher Reviews
I like the helpful info you provide to your articles. I’ll bookmark your blog and check again right here regularly.
I am fairly sure I’ll be informed many new stuff right right here!
Good luck for the next!
Feel free to visit my web site – Neo Bio Health Keto
Hi, Neat post. There’s an issue along with your site in internet explorer, would
test this? IE still is the marketplace chief and a
huge component of other folks will pass over your wonderful writing
due to this problem.
Also visit my web-site :: Infinuity CBD Gummies
If some one wishes to be updated with most up-to-date technologies then he must be visit this website and be
up to date every day.
Greetings from California! I’m bored at work so I decided
to browse your website on my iphone during lunch break.
I really like the information you present here and can’t wait to
take a look when I get home. I’m shocked at how fast your blog loaded on my cell phone ..
I’m not even using WIFI, just 3G .. Anyways, very good site!
Here is my page; Eagle CBD Review
Definitely, what a great blog and informative posts, I surely will bookmark
your site.Best Regards!
my site True Keto 1800
You need to take part in a contest for one of the best websites on the web.
I’m going to recommend this site!
If you would like to get much from this piece of writing then you
have to apply such strategies to your won web site.
Also visit my website … Keto Incinerate
Thank you for any other great post. The place else could anybody get that type of info in such
an ideal approach of writing? I have a presentation next week, and I’m
on the look for such information.
I’m truly enjoying the design and layout of your website.
It’s a very easy on the eyes which makes it much more
pleasant for me to come here and visit more often. Did you hire out
a designer to create your theme? Excellent work!
Howdy! I could have sworn I’ve been to this
site before but after looking at many of the articles I realized it’s
new to me. Nonetheless, I’m certainly happy I
found it and I’ll be bookmarking it and checking back often!
My web page :: Nature Fused Cream Review
I don’t even know how I finished up here, but I believed this submit was good.
I don’t understand who you are but certainly you are
going to a famous blogger for those who are not already.
Cheers!
Feel free to visit my homepage; psicura.it
Wonderful items from you, man. I have take note your stuff previous to and you are simply too great.
I actually like what you’ve received here, really like what
you are stating and the way in which you say it. You’re making it entertaining and you
still take care of to stay it wise. I can not wait to learn much more from
you. This is actually a wonderful web site.
My web blog … Infinuity CBD Price
Hello, i believe that i noticed you visited my site thus i came to ?return the favor?.I’m
trying to find issues to enhance my site!I suppose
its adequate to use a few of your concepts!!
Here is my page; Luiresse Review
I just like the helpful information you supply to your articles.
I’ll bookmark your blog and check again right here frequently.
I am quite certain I will learn a lot of new stuff proper right
here! Best of luck for the following!
My blog – True Keto
I couldn?t refrain from commenting. Exceptionally well written!
my page Arctos Air Cooler
Thanks for sharing your thoughts about benefits of hemp seed oil.
Regards
Feel free to visit my web blog; Niva CBD Gummies
I was just seeking this information for some time. After six hours of continuous Googleing, at last I got it in your website.
I wonder what’s the lack of Google strategy that don’t rank
this type of informative sites in top of the list. Generally the top web sites are full of garbage.
my page Insights CBD Gummies Review, Dorthea,
I would like to consider the ability of thanking you for that professional guidance I have often enjoyed going
to your site. We are looking forward to the particular commencement of my college research and the
overall preparation would never have been complete without consulting this site.
If I might be of any assistance to others, I might be glad to help by means
of what I have gained from here.
Visit my web site Pure Keto Burn Review
Good article! We are linking to this great article on our
website. Keep up the great writing.
My web site – Modern Belle Skin Care
Wonderful post! We will be linking to this great article on our website.
Keep up the good writing.
Also visit my web blog :: walnut.ut.ac.ir
Simply want to say your article is as astounding. The clarity in your post is just spectacular and i could assume you are an expert
on this subject. Well with your permission allow me to
grab your feed to keep up to date with forthcoming post.
Thanks a million and please continue the rewarding work.
My blog … Desiree
When someone writes an article he/she keeps the image of a user in his/her mind that how a user can be
aware of it. So that’s why this piece of writing is amazing.
Thanks!
my site … Vigor Max Male Enhancement Review
(vip5.moisait2021.ru)
Very efficiently written post. It will be valuable to anybody who employess it, as well as me.
Keep doing what you are doing – for sure i will check out more posts.
Also visit my homepage: Keto Incinerate Pills
Wow, that’s what I was searching for, what a stuff!
existing here at this blog, thanks admin of this website.
Here is my web page :: Scot
I do not know if it’s just me or if everybody else encountering problems with
your site. It appears as though some of the text in your content are running
off the screen. Can someone else please comment and
let me know if this is happening to them too?
This could be a problem with my internet browser because I’ve had this happen before.
Kudos
Hiya very nice blog!! Man .. Beautiful .. Amazing ..
I’ll bookmark your website and take the feeds additionally…I’m glad to search out numerous helpful information here in the submit, we want develop more techniques on this regard,
thank you for sharing.
My web blog Hydrofirm Cream
What’s up i am kavin, its my first occasion to commenting anywhere, when i read this paragraph i thought i could also create comment due to this good article.
Review my web-site Derma Ella Skin Care
I have been absent for a while, but now I remember why I used
to love this website. Thanks, I will try and check back more frequently.
How frequently you update your web site?
My webpage :: shihan.com.ru
Article writing is also a excitement, if you know afterward
you can write if not it is difficult to write.
My site :: NeoPodz
Undeniably believe that which you said. Your favorite reason appeared to be on the net the easiest thing to be aware
of. I say to you, I certainly get irked while people consider
worries that they just do not know about.
You managed to hit the nail upon the top and also defined out the whole thing without having side-effects , people could take a signal.
Will likely be back to get more. Thanks
Also visit my web blog: Far East XL Pills
If you would like to grow your experience just keep
visiting this web site and be updated with the latest information posted here.
Also visit my webpage; USlim X Keto BHB
Do you have a spam problem on this blog; I also am a blogger,
and I was wanting to know your situation; many of us have created some nice procedures and we are looking to swap techniques with
other folks, please shoot me an email if interested.
Stop by my webpage … NeoBio Keto Reviews
You can certainly see your expertise within The Skin Company Anti Aging Cream work you write.
The arena hopes for more passionate writers such as you who aren’t afraid to mention how they
believe. All the time follow your heart.
I simply could not depart your web site before suggesting that I
actually enjoyed the usual info a person provide on your visitors?
Is gonna be again regularly to investigate cross-check new posts
My brother suggested I would possibly like this web site.
He was once totally right. This publish truly
made my day. You cann’t believe simply how a lot time I had spent for
this information! Thanks!
Also visit my web blog; Optimum Keto Ingredients
Hmm is anyone else having problems with the images on this blog loading?
I’m trying to find out if its a problem on my end or if it’s the blog.
Any suggestions would be greatly appreciated.
That is a good tip especially to those fresh to the blogosphere.
Brief but very accurate information? Thanks for sharing this one.
A must read post!
Here is my site Vigor Max Male Enhancement Review
I visited several web sites however the audio
quality for audio songs existing at this website is actually
excellent.
My blog … Neo Bio Health Keto
Superb blog! Do you have any suggestions for aspiring writers?
I’m planning to start my own blog soon but I’m a
little lost on everything. Would you suggest starting with a free platform like WordPress or go for a paid option? There
are so many choices out there that I’m completely overwhelmed ..
Any tips? Bless you!
I blog often and I truly appreciate your content.
This article has truly peaked my interest. I’m going to bookmark your site and keep checking for
new information about once a week. I opted in for your Feed as
well.
my web-site: Biodermeux Review
This is a topic which is close to my heart… Take care! Exactly where are your contact details though?
my web blog – True Keto
Good response in return of this difficulty with real arguments and telling all on The Skin Company topic
of that.
Excellent beat ! I wish to apprentice at the same time as
you amend your site, how could i subscribe for a blog website?
The account aided me a applicable deal. I were tiny bit acquainted
of this your broadcast provided vibrant transparent
concept.
Look into my web page – True Burn Keto Pills [163.30.42.16]
Every weekend i used to pay a quick visit this
website, because i want enjoyment, for the reason that
this this website conations genuinely fastidious funny material too.