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TWiV 172 Letters

Greg writes:

Dear TWiV,

The epidemiology episode with Michael Walsh was great. I loved the philosophical detour into counterfactual statements, time travel, and the meaning of causation. TWiV may indeed be viral, but from listening to it I feel inoculated against the micro-specialization that is endemic to so much of science.

Dr. Walsh's rigorous stance against making statements of causation based on epidemiological studies reminded me of the following xkcd webcomic:


Allow me to thank you all for putting on TWiV, TWiM, and TWiP. I'm a physicist who has inexplicably become a postdoc in biomedical engineering. I find each of your podcasts to be a revelatory journey into biology. Often I return with something I feel like talking about to complete strangers.

All the best,


Øystein writes:

Dear Vincent:

I’m writing you to thank you for a truly inspiring present! I’m a Norwegian veterinarian doing a Phd in virology at the Norwegian School of Veterinary Science. I’m a big fan of your podcast and a little while ago my girlfriend apparently contacted you, regarding our three year anniversary and my birthday in December. I don’t known if you remember this, but she asked if you could write a little letter to me for this occasion. To my surprise, included in her gift was an envelope marked Columbia University, New York. No technological gadget or other materialistic gift could have beaten this present. Inspiration can’t be bought, and I really appreciated that you took the time to write me. You and your crew on TWIV are truly a source of knowledge and motivation. Your podcast has really educated me both in virology and the scientific way of thinking.

In my PhD I’m working on a novel reovirus called Piscine reovirus (PRV). PRV is associated with Heart and Skeletal Muscle Inflammation (HSMI) that is an emerging disease in farmed Atlantic salmon. The virus was actually discovered in 2009/2010 in collaboration between the lab of my supervisor Dr. Espen Rimstad at the Norwegian School of Veterinary Science and Dr. Ian Lipkin’s lab at Colombia University New York, using high throughput sequencing. Thanks to their work a PhD position later opened up to study this new virus, and that’s how I got into virology. I really enjoy the field, and TWIV has made it even more interesting. Thank you, Alan, Rich and Dickson for your superior podcast. Keep up the good work, I hope you are motivated to continue for a long time.

By the way, the temperature in Oslo is -5°C.




Thomas writes:

Dear sirs,

Firstly, happy new year to the entire gang. I look forward to another wonderful year for all 3 podcasts. I hope you reached your 1000 mark for your listener survey and I am excited to see where TWIV goes from here.

My main reason for writing today is in response to some comments made during the year in review TWIV (#164). I believe it was Rich that made the observation that most of the articles that were chosen were somehow implicated in human disease and pathogenesis. He then went on to mention that many of the issues with some of the more controversial stories dealt with the public's knowledge of science and how projects, such as the H5N1 influenza project, are portrayed in the media. (P.S. Thank you Vincent for the articles on the TWIV Facebook page! It helps me to keep on top of the issue without having to search through various sources).

I'm not sure what your experiences in college were. but mine involved that of a small Catholic liberal-arts college in rural NY state. Here we were required to complete the compulsory courses to obtain our B.As, B.Ss, etc. along with the compulsory courses as part of the the liberal arts curriculum. Topics in this curriculum included micro-economics, sociology, sacred texts of various religions, and an intro to science and the scientific process, to name a few. I felt I left the school with a general understanding of many topics to an extent where I am less intimidated by balancing a checkbook, confident in being able to converse and interact with peoples of various religious backgrounds, and obviously an extensive knowledge of science given my studies in biochemistry.

My question to you gentlemen is this: Do you feel that a liberal arts education would help the situation discussed during TWIV where it appears that the general public is just not "competent" in the scientific process and how science actually works? I feel that my introduction to foreign subjects such as micro-economics and religious texts was sufficient for me to feel less ignorant of the material and confident enough to make prudent decisions should I be faced with one concerning such topics. Thus, I would hope that my classmates who were not science majors and were introduced to very basic level scientific concepts and the scientific process would similarly feel more confident in not being lead down the wrong path by media or other sources.

I apologize for the length of the e-mail but I sincerely believe that the liberal-arts education I received was excellent for the reasons I alluded to above and I wonder what your opinions are on the matter. Keep up the great work and all the best in 2012 and many years thereafter.

Mike writes:

Hello TWIVites!

I just recently listed to episode # 164, and was delighted to hear your response to my question. Thank you so much for taking the time to contact your colleague and relay my question to her. I very much appreciated her taking the time to respond, and the depth of her answer. However, the answer left me with yet still more questions. The colleague you mentioned in your response seems to be pursuing a type of therapy that involves using various cellular signaling factors to activate transcription of the viral genome in an otherwise latent cell. Once the viral genes are transcribed and the virus begins to actively replicate, antiretroviral therapy is used to prevent the spread of the virus to uninfected cells while attempting to kill the viral infected cell with another form of anti-viral therapy. Your colleague (Kathleen Collins M.D./Ph.D.) said that the trick to all this is finding a balance between efficacy and toxicity - in other words...kill the bad cells, but leave the good ones alone. I found her answer to be very complete and satisfying to the question that I asked, but now I have a few more...

1.) Is it true that HIV can only infect cells that are positive for the CD4 receptor?

2.) If question #1 is true, does a CD4+ cell infected with HIV express any cellular surface markers that uniquely identify it while not alerting the immune system when it is still in a latent state?

3.) If the answer to question #2 is "yes", would it be possible to engineer a monoclonal antibody that can tag that unique surface receptor?

4.) If the answer to question #3 is "yes", would it then be possible to tag that antibody with yet another antibody that is ferromagnetic? (Or maybe just make the first antibody ferromagnetic)

I recently saw a program on the Discovery channel that showed a recent experiment involving rats and longevity. In this experiment, the researchers used this kind of antibody tagging system to remove senescent cells from the bodies of aging rats. The whole process used a piece of equipment that looked somewhat similar to a dialysis machine. The machine used a magnetic field to pull senescent cells out of the blood as the blood was filtered through by pulling on a ferromagnetic antibody attached to those cells. The blood was then pumped back into the rat. The rat behaved like a much younger rat after that and did not show many of the aging related diseases that other rats who had not undergone this procedure did. I suppose my ultimate question is this...

Could this same process be adapted for HIV, or for any viral infection for that matter where a unique surface protein/glycoprotein (or any other kind of marker) is expressed on the cellular surface?

Thank you for taking the time to read this, and I will understand if you do not respond due to the length of this email. Also, I would like to thank all of you for what you do. I listen to your podcasts (TWIM, TWIV, and TWIP) on my way to work and it makes the drive go much faster! Please forgive me if this is an ignorant line of question as I am somewhat of a layman - I only have a couple of Bachelor's degrees in science. Once again...thank you!

P.S. Please tell Dickson that I live in the Chicagoland area and will be touring his vertical farm project in the next few weeks!

Eric writes:

Dear Professors,

I am a twiv listener and I enjoy your podcast and trust your judgement.

I recently came across this story. I would appreciate your thoughts. Is there any truth here at all? The story is fairly short. Knowing what the government did to Soldiers in the 1950's I can't reject this out of hand. If this is all just BS, then it needs to be exposed.



Here's a link to the story which I also pasted below.


The linked story also links to a few books; one which has high reviews,


Margot writes:

i've just started listening to you guys [no gals?] and am enjoying it.

here's my question [and i've only listened to a two so far, maybe you've addressed this already]: do viruses have any positive effect on humans? we've discovered so many important roles bacteria play but the only good thing i've heard about viruses is that they have influenced our evolution.






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