COVID 19 Vaccine Deep Dive: Safety, Immunity, RNA Production, w Shane Crotty, PhD (Pfizer / Moderna)

December 17, 2020 32 Views

Professor Shane Crotty, PhD answers a series of COVID 19 vaccine questions including what are the chances of long-term side effects? How safe is RNA vaccine (i.e. Pfizer / BioNTech and Moderna Vaccines) technology? How long does mRNA from a vaccine stay in our cells? What else goes in vaccines? How long does immunity last? Why are T-Cells so important? Why does Pfizer’s vaccine need to stay SO cold?
Shane Crotty, PhD is a Professor at the La Jolla Institute for Immunology, Center for Infectious Disease and Vaccine Research, Crotty Lab. Professor Crotty also has an academic appointment with the University of California San Diago. See his full bio here:
Professor Crotty on Twitter:

Interviewer: Kyle Allred, Physician Assistant, Producer and Co-Founder of

See our new interview with Prof. Crotty on how virus mutations (UK variant and S. African variant) may be impacting COVID-19 transmission and vaccine efficacy.

Research referenced in this video from Prof. Crotty and his team was published Jan. 6, 2021, in the prestigious Journal Science:

New York Times article highlighting Prof. Shane Crotty’s research:

00:00 Introducing Prof. Shane Crotty’s Research
0:35 How long does COVID-19 “immune memory” last?
0:57 The three primary aspects of immune memory: antibodies, killer T cells, and helper T cells
2:25 The anatomy (protein makeup) of SARS-CoV-2
3:02 Why is spike protein the primary target?
5:17 Could a mutation allow SARS-CoV-2 to infect without spike protein?
7:02 Utilizing lipid nanoparticles to deliver mRNA and the role of RNA normally
9:52 What human cells does an RNA vaccine go into?
10:36 How long does mRNA from a vaccine stay in human cells?
11:44 What else goes in vaccines besides mRNA and lipid nanoparticles? Any preservatives or adjuvants?
12:30 Why are adjuvants used in many vaccines?
14:08 Protein production from mRNA
15:00 Why utilize the “extra” step of mRNA to code for protein antigens?
17:28 Are mRNA vaccines the future of vaccine development?
19:18 Any chance for mRNA to enter our cells’ nucleus?
20:55 The immune response to a coronavirus vaccine
23:17 Expected symptoms from immune response to a vaccine vs. vaccine side effects
25:50 Should people who’ve had COVID-19 get vaccinated?
27:27 Immunity from COVID vaccine vs. a natural infection
28:30 Why does the Pfizer vaccine need to be stored so cold?
29:04 What would you say to a family member who is nervous about a rushed vaccine and RNA technology?
32:37 What about the possibility of long term side effects from RNA vaccines?
33:30 What’s next for Shane Crotty’s research team?

(This video was recorded on December 16, 2020).


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Video Produced by Kyle Allred



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Join the Conversation


  1. See other recent MedCram Interviews: Ventilate Your Home! Optimize Health with Prof. Joseph Allen:
    Coronavirus Mutations and Vaccine Implications with Prof. Shane Crotty, PhD:
    If You Get COVID 19 with Prof. Roger Seheult, MD: 10 Tips to Optimize Immune System:
    Vitamin D and COVID 19 with Prof. Roger Seheult, MD:
    At Home COVID 19 Antigen Test Update with Prof. Michael Mina, MD
    Clear explanations of over 60 topics at our website

  2. I have a few questions regarding this video. First of all I need to say that I am fresh, young molecular biologist (not even graduated) who is inconceivably interested in genetics, viruses and especially corona virus. My first question is does we know how many mRNA are in one sample of vaccine and how many cells do get that mRNA? Another one that I thought a lot about is when we take the vaccine and our cells start producing spike proteins does this mean that our immune system will recognize that cells as enemies because they have corona spike protein attached to their cell membrane? Really hoping for answers and thank you A LOT in advance ???

  3. As I am to understand, a person who has been vaccinated still can contract and transmit the virus. My question is; In this scenario, is the virus transmitted from a vaccinated person crippled so to speak? If they have the antibodies that attach themselves to the virus, is that virus being transmitted with those antibodies thus making the virus less effective to the person who comes in contact with it?

  4. Appreciate this detailed interview. My question regarding assessing long-term safety with two month data is this; Why do we have a number of immunologist admitting they would wait at least a year to 18 months before taking the vaccine themselves? On live TV program called Straight Talk in Hong Kong we had two doctors reluctantly admit on air that they would wait when posed this question. I've no doubt if this virus was truly deadly like the spanish flu they would not hesitate. However evidently they feel it's worth waiting even with a low probability of longer-term side effects which presumably could be worse than long covid, otherwise why wait?

  5. Do you expect that annual vaccinations will become the norm as wild mutations emerge on an annual basis?

    Their is growing evidence that your immune system is dependant on a functioning microbiome. The types of bacteria and its diversity is a vital component in having an effective immune response. So if your microbiome has been impaired through over use of antibiotics would you have sufficient resources to mount an immune response?

    Given that the vaccine is only eliciting temporary protection and its your immune system that is actually doing the protection, wouldn't it make sense to improve our immune function over having to keep vaccinations up to date every year?

    Wouldnt it make better sense to screen for compromised immune function and treat that instead?

    As you say RNA is very fragile, is there a possibility of it getting damaged as it enters the cell and a different protein being created?

    Then through the RNA production of a different spike protein in your cell and subsequent immune response that is elicited, is it possible for the manufactured Spike protein to be categorised as a mutation?

  6. Very solid interview. Neither of these people were "selling" anything. And although the government has absolved the makers of liability, a mass problem with the vaccine basically kills these two companies. They have a combined market value of 90 Billion dollars and expect to make an additional 40 billion on the vaccine. I can imagine the CEO sitting with everyone before they put their OK stamp on this vaccine. "OK everyone, we are going to make a lot of money it this works and we are all fired and out of business if it hurts a bunch of people". If people died from it, other countries would bring criminal charges. This vaccine is as safe as can be expected. How much risk would you take if you were investing 90 billion. That's right; NONE!

  7. Thank you for this video – very intelligible , comforting answers and explanations; and the questions asked were also so clear and apt!

    And thank you in general to MedCram! This video (and the others I’ve seen from this channel esp relating to sarscov2) have been very helpful !

  8. I got covid-19 in February, developed a severe form of lower lobe pneumonia that wasn't covered by my pneumococcal vaccine, was hospitalized, and later took 6 weeks recovery at home. I asked for an antibody test about 7 months later and came up negative for natural inoculation. I also have an autoimmune problem. So my body goes overboard in killing anything that irritates. I have found that I can't even keep immunity from chicken pox regardless of getting it as a child and getting vaccinated (my titers are too low); so I have to get a regular booster of varicella vaccine to maintain protection. I wonder if scientists are taking a look at people like me who have this inflammatory response (including those with arthritis for example.)

  9. Thank you . I now have a rudimentary understanding of the new technology in vaccination. Couple of questions: 1) if RNA self destructs after the code has been delivered to the cell, how will the body produce enough spike proteins to build immunity? How many strands of DNA are delivered in one dose of the vaccine? 2) Since the RNa has to be introduced into the cell in order for it to produce the spike protein, can it go into any cell or can specific cells be targeted? And would there be certain cells, that should not be targeted?
    3) Reading more than a few occurrences of people suffering side effects from rashes, convulsions, paralysis to death. Any explanations for the adverse reactions?

  10. Outstanding! Prof. Crotty has a gift for explaining the complexity of viruses and vaccines clearly, and Kyle Allred did a great job of teeing up the right questions. One question I and some other posters have is how to reconcile the transient nature of the mRNA vs. the need to ensure that enough spike protein is made to trigger the immune response? Would it make sense to split the dose and inject the half-doses into different areas (say left arm, right arm, or arm and thigh) to get more spike protein generated to trigger stronger immune response?

  11. How will life saving blood transfusions affect those who receive blood from a vaccinated person? I'm not sold on M-RNA, we do not know long term effects on how it will affect our DNA. It's irresponsible not to question this. I'll take my chances on natural immunity.