by getting the immune system all worked up.

通過讓免疫系統全部工作起來。

But this is exactly what causes those unpleasant side effects that can knock you off your game

但這正是導致那些令人不快的副作用的原因，會使你失去遊戲的動力

for a day or two.

一兩天的時間。

So, while the fatigue, headache and low grade fever are no fun, they can actually be proof

是以，雖然疲勞、頭痛和低燒並不好玩，但它們實際上可以證明

that the vaccine is doing its job and doing it well.

疫苗正在做它的工作，而且做得很好。

Your immune system is actually already quite good at getting rid of viruses but it isn't

你的免疫系統實際上已經非常善於擺脫病毒，但它並不是

all knowing, and when it encounters a new virus like the one that causes COVID-19, it

當它遇到像導致COVID-19的新病毒時，它會

needs to be taught some new tricks.

需要教一些新的技巧。

And the best way to do this is through a vaccine that tells your body what to do if it encounters

而做到這一點的最好方法是通過疫苗，告訴你的身體在遇到以下情況時應該怎麼做

the virus, essentially creating what's called a memory response.

病毒，本質上創造了所謂的記憶反應。

Now everybody responds differently to a vaccine or an infection.

現在每個人對疫苗或感染的反應都不同。

And so everybody's memory response is a little different, but the vast majority of people

是以，每個人的記憶反應都有些不同，但絕大多數人

their memory response is so fast so strong that it clears that infection from that virus

他們的記憶反應是如此之快，如此之強，以至於可以清除該病毒的感染。

before it really has a chance to get established.

在它真正有機會建立起來之前。

And so you won't have any symptoms, you won't even know you're infected.

是以你不會有任何症狀，你甚至不會知道你被感染了。

Hi my name is Rick Kennedy.

嗨，我的名字是裡克-肯尼迪。

I'm a professor of medicine at the Mayo Clinic.

我是梅奧診所的醫學教授。

I'm an immunologist by training, I study vaccines and infectious diseases, and I run the vaccine

我是一名受訓的免疫學家，我研究疫苗和傳染病，我負責疫苗的工作。

research group here at Mayo Clinic.

在梅奧診所這裡的研究小組。

So creating a memory response to a virus is key.

是以，建立對病毒的記憶反應是關鍵。

But how exactly does a vaccine do this?

但疫苗究竟是如何做到這一點的？

Well, it might help to start with an understanding of how the immune response works.

那麼，從瞭解免疫反應的運作方式開始，可能會有所幫助。

The first part of the immune system

免疫系統的第一部分

is called the innate immune system.

被稱為先天免疫系統。

It's sort of your first line of defense.

這算是你的第一道防線。

It has three main jobs; the first job is to recognize that you're infected and sound the

它有三項主要工作；第一項工作是認識到你被感染了，併發出警報。

alarm.

警報。

The second job is to try and recruit white blood cells and send them to the site of infection

第二項工作是嘗試招募白細胞，並將它們送到感染部位。

to try and slow it down.

以試圖減緩它。

And then the third and probably the most important thing is to take the virus or the bacteria

然後第三件事，也可能是最重要的一件事，就是把病毒或細菌

that's infecting us and take it back to the rest of the immune system so that it can learn

感染我們的病毒，並將其帶回免疫系統的其他部分，以便它能夠學習

to recognize and then destroy it.

來認識，然後摧毀它。

The innate immune system fires up as soon as the virus gets into the body,

一旦病毒進入體內，先天免疫系統就會立即啟動。

and it's that flood of immune activity that can cause symptoms like fever or muscle aches.

而正是這種大量的免疫活動可能導致發燒或肌肉痠痛等症狀。

It sets the stage for the next phase of response, the adaptive immune response.

它為下一階段的反應，即適應性免疫反應創造了條件。

T cells and B cells are part of what's called the adaptive immune response.

T細胞和B細胞是所謂的適應性免疫反應的一部分。

So the first part of that are B cells, they're basically antibody factories, and each B cell

所以第一部分是B細胞，它們基本上是抗體工廠，而每個B細胞

is specific for one little piece of one viral protein and that's called an epitope.

是對一個病毒蛋白的一小塊的特異性，這被稱為表位素。

The antibodies produced by B cells will bind to this epitope and can block the virus from

B細胞產生的抗體將與這一表位結合，並能阻止病毒侵入。

attaching to or entering cells, they might be called B cells but they're really the A team.

附著於或進入細胞，它們可能被稱為B細胞，但它們實際上是A團隊。

Then there are the T cells.

然後是T細胞。

Those are important because once a virus gets inside your cells,

這些很重要，因為一旦病毒進入你的細胞內。

the antibodies can't get to it, so it's hidden from the antibodies and it's going to turn

抗體無法接觸到它，所以它被隱藏起來，不被抗體發現，它將會變成

that cell into a virus factory and produce more viruses, that's how the virus spreads

該細胞成為病毒工廠併產生更多的病毒，這就是病毒傳播的方式。

through your body. You have killer T cells and helper T cells.

通過你的身體。你有殺傷性T細胞和輔助性T細胞。

The killer T cells hunt down and kill infected cells, and yes

殺傷性T細胞追捕並殺死受感染的細胞，而且是

you guessed it helper T cells, help them.

你猜對了，就是輔助T細胞，幫助他們。

You want to have both a strong innate immune response, and a strong adaptive immune response

你希望同時擁有強大的先天免疫反應和強大的適應性免疫反應

to fight a virus, so every vaccine needs to have ingredients that trigger both.

來對抗病毒，是以每一種疫苗都需要有觸發這兩方面的成分。

Vaccines have two main components at least from the perspective of the immune system.

至少從免疫系統的角度來看，疫苗有兩個主要組成部分。

There's the part that would stimulate the innate immune response and that's called an

有一個部分會刺激先天性免疫反應，這被稱為一個

adjuvant and that's typically a molecule or a pattern that's found in a virus or bacteria

佐劑通常是病毒或細菌中的一種分子或模式。

that's not present in humans.

這在人類中是不存在的。

When you're injected with a vaccine and the innate response is triggered, that's where

當你被注射了疫苗，先天性反應被觸發，這就是

a lot of those well known symptoms come in the burst of activity to the site of the vaccination

很多眾所周知的症狀都是在接種疫苗的地方突然出現的。

is why your arm gets sore after a shot.

是為什麼你的手臂在打完針後會痠痛。

The other component is the antigen.

另一個組成部分是抗原。

And that's really the piece that we're trying to have the T cells and the T cells target

而這確實是我們試圖讓T細胞和T細胞瞄準的那一塊。

and respond to.

並作出迴應。

So no matter which vaccine you get, you're getting a mixture with an antigen and an adjuvant

是以，無論你接種哪種疫苗，你都會得到一種帶有抗原和佐劑的混合物。

injected into your muscle cells,

注入你的肌肉細胞。

There's some specialized cells called antigen presenting cells, they act like garbage disposals

有一些特殊的細胞被稱為抗原呈遞細胞，它們的作用就像垃圾處理機。

and trash collectors, they just sample the environment so they will see the antigen and

和垃圾收集者，他們只是對環境進行採樣，所以他們會看到抗原和

pick it up, they'll see the adjuvant and say oh, something's wrong here, and then they'll

拾起它，他們會看到佐劑，然後說哦，這裡有問題，然後他們會

carry the antigen, to the lymph node. Lymph nodes are basically like a shopping mall,

攜帶抗原，到淋巴結。淋巴結基本上就像一個購物中心。

T cells and B cells are coming in and out all of the time, and every T cell and every

T細胞和B細胞一直在進進出出，而每個T細胞和每個

B cell is looking for that one shirt on the rack that one epitope, that one piece of

B細胞正在尋找架子上的那件衣服，那件表位素，那件

the viral protein that it recognizes.

它所識別的病毒蛋白。

This process happens in the first few days as the B cells learn to make antibodies and

這一過程發生在最初幾天，因為B細胞學會了製造抗體和

T cells learn to kill cells, or how to help kill cells.

T細胞學會殺死細胞，或如何幫助殺死細胞。

They're also proliferating, growing and dividing and making clones of themselves because you'll

它們也在增殖，生長和分裂，製造自己的克隆，因為你會

need an army of these white blood cells to fight off the army of viral particles that

需要一支由這些白細胞組成的軍隊來擊退病毒顆粒的軍隊。

is present in your body and infected, and that whole process takes about a week or two.

是存在於你的身體並被感染，而這整個過程大約需要一到兩個星期。

Now for an infection that's where the story ends, but for a vaccine, you're really not

現在，對於感染來說，故事就到此為止了，但是對於疫苗來說，你真的不能

trying to protect you against the vaccine you're protecting against a future infection.

試圖保護你的疫苗，你要保護你免受未來的感染。

Your body clears the antigen and the innate response calms down, then most of the T cells

你的身體清除了抗原，先天反應平靜下來，然後大部分T細胞

and B cells will die off as their services are no longer needed, but some of them will

和B細胞將死亡，因為不再需要它們的服務，但其中一些細胞會

change into memory cells.

變為記憶細胞。

Memory cells will last for years, sometimes decades, they just circulate through your

記憶細胞將持續數年，有時甚至數十年，它們只是在你的身體裡循環。

body and they're fairly quiet until you run into that virus again.

身體，他們相當安靜，直到你再次遇到這種病毒。

Now, a naive cell the first time it sees antigen and it's learning to do its job, it's a little

現在，一個幼稚的細胞在第一次看到抗原時，正在學習做它的工作，它有一點

bit like an infant taking its first steps, a memory cell, it's the equivalent of an Olympic

有點像嬰兒邁出的第一步，一個記憶細胞，它相當於一個奧運冠軍。

caliber athlete, it takes off running at full speed and it's fast, so the difference

運動員，它全速奔跑，速度很快，所以區別在於

between your memory response, and that initial response is that the memory response is 100

你的記憶反應和最初的反應之間的關係是，記憶反應是100

sometimes 1000 times stronger.

有時強1000倍。

Okay, sign me up for these Olympic caliber cells ASAP.

好吧，儘快給我報名參加這些奧林匹克口徑的細胞。