Marc Veldhoen
@marcveld.bsky.social
Professor of Immunology 🇳🇱 🇬🇧
Lisbon, 🇵🇹
#Immunology
Time for Science, not silence
https://scholar.google.co.uk/citations?user=7vG1jLIAAAAJ&hl=en
https://orcid.org/0000-0002-1478-9562
threads.net/@marc_veld
mastodon.online/@marc_veld
Lisbon, 🇵🇹
#Immunology
Time for Science, not silence
https://scholar.google.co.uk/citations?user=7vG1jLIAAAAJ&hl=en
https://orcid.org/0000-0002-1478-9562
threads.net/@marc_veld
mastodon.online/@marc_veld
Pinned
Marc Veldhoen
@marcveld.bsky.social
· Nov 29
What will population immunity to SARS-CoV-2 look like in a post-vaccine world?
An updated outlook (2025)
marcveldhoen.substack.com
Five years of COVID taught us one thing: immunology didn’t fail, our public discourse did. My new Substack cuts through the noise with evidence, not ideology. If you want facts over fear, and science over spin, join here:
marcveldhoen.substac...
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marcveldhoen.substac...
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Strange that COVID-19 arrived in April 2019, not?
In NL, a large part is due to increasing stress. There may be additional unknowns. To blame this on SC2, especially on "accumulated" damage is without biological data. But, such claims without merrit can inhibit the investigation to real causes.
In NL, a large part is due to increasing stress. There may be additional unknowns. To blame this on SC2, especially on "accumulated" damage is without biological data. But, such claims without merrit can inhibit the investigation to real causes.
February 10, 2026 at 9:51 PM
Strange that COVID-19 arrived in April 2019, not?
In NL, a large part is due to increasing stress. There may be additional unknowns. To blame this on SC2, especially on "accumulated" damage is without biological data. But, such claims without merrit can inhibit the investigation to real causes.
In NL, a large part is due to increasing stress. There may be additional unknowns. To blame this on SC2, especially on "accumulated" damage is without biological data. But, such claims without merrit can inhibit the investigation to real causes.
Reposted by Marc Veldhoen
Science does not claim moral purity. It claims something more robust: procedures that work despite human imperfection. Those procedures are visible, documented, boring and unglamorous. Which is apparently why conspiracy narratives must make them sound sinister.
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January 31, 2026 at 7:35 PM
Science does not claim moral purity. It claims something more robust: procedures that work despite human imperfection. Those procedures are visible, documented, boring and unglamorous. Which is apparently why conspiracy narratives must make them sound sinister.
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Reposted by Marc Veldhoen
Adult obesity and risk of severe infections: a multicohort study with global burden estimates
Adult obesity is a risk factor for infection-related hospitalisations and mortality across diverse pathogen types, causing ~1/10 infection-related deaths.
www.thelancet.com/jo...
1/6
Adult obesity is a risk factor for infection-related hospitalisations and mortality across diverse pathogen types, causing ~1/10 infection-related deaths.
www.thelancet.com/jo...
1/6
February 10, 2026 at 10:42 AM
Adult obesity and risk of severe infections: a multicohort study with global burden estimates
Adult obesity is a risk factor for infection-related hospitalisations and mortality across diverse pathogen types, causing ~1/10 infection-related deaths.
www.thelancet.com/jo...
1/6
Adult obesity is a risk factor for infection-related hospitalisations and mortality across diverse pathogen types, causing ~1/10 infection-related deaths.
www.thelancet.com/jo...
1/6
Reposted by Marc Veldhoen
Ik dacht heel even: wie in Nederland gaat dit serieus nemen?
Een vodje, geen wetenschap maar fantasierijke speculatie gebaseerd op onzin, biologische onmogelijkheden en niet‑causale casestudies.
Het antwoord was eigenlijk al duidelijk.
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Een vodje, geen wetenschap maar fantasierijke speculatie gebaseerd op onzin, biologische onmogelijkheden en niet‑causale casestudies.
Het antwoord was eigenlijk al duidelijk.
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February 10, 2026 at 2:48 PM
Ik dacht heel even: wie in Nederland gaat dit serieus nemen?
Een vodje, geen wetenschap maar fantasierijke speculatie gebaseerd op onzin, biologische onmogelijkheden en niet‑causale casestudies.
Het antwoord was eigenlijk al duidelijk.
1/2
Een vodje, geen wetenschap maar fantasierijke speculatie gebaseerd op onzin, biologische onmogelijkheden en niet‑causale casestudies.
Het antwoord was eigenlijk al duidelijk.
1/2
Reposted by Marc Veldhoen
Vrijheid.
Het maken van een cartoon. Sarcasme, karikatuur, enz. Het aan de kaakstellen van mistanden.
Zoals deze van Joep Bertrams (Joep Bertrams). Het geeft de koers van de FvD aan die mensen toelaat met een dubieus extreem rechts verleden.
1/2
Het maken van een cartoon. Sarcasme, karikatuur, enz. Het aan de kaakstellen van mistanden.
Zoals deze van Joep Bertrams (Joep Bertrams). Het geeft de koers van de FvD aan die mensen toelaat met een dubieus extreem rechts verleden.
1/2
February 10, 2026 at 2:31 PM
Vrijheid.
Het maken van een cartoon. Sarcasme, karikatuur, enz. Het aan de kaakstellen van mistanden.
Zoals deze van Joep Bertrams (Joep Bertrams). Het geeft de koers van de FvD aan die mensen toelaat met een dubieus extreem rechts verleden.
1/2
Het maken van een cartoon. Sarcasme, karikatuur, enz. Het aan de kaakstellen van mistanden.
Zoals deze van Joep Bertrams (Joep Bertrams). Het geeft de koers van de FvD aan die mensen toelaat met een dubieus extreem rechts verleden.
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It is all intertwined. Some immune cells express high levels of GLP1R and can even modulate systemic GLP1 levels. Indeed, any of these studies has additional confounders, a GLP1 agonist group would be nice for next time!
February 10, 2026 at 3:27 PM
It is all intertwined. Some immune cells express high levels of GLP1R and can even modulate systemic GLP1 levels. Indeed, any of these studies has additional confounders, a GLP1 agonist group would be nice for next time!
Should one see?
First of all, getting a paper published is not just sending it, making a few changes, and moving on to the next one. It is frequent rejections, sometimes many times, delays, much more work to be done, and possibly rejection again. More experiments, etc.
1/5
First of all, getting a paper published is not just sending it, making a few changes, and moving on to the next one. It is frequent rejections, sometimes many times, delays, much more work to be done, and possibly rejection again. More experiments, etc.
1/5
February 10, 2026 at 2:48 PM
Ik dacht heel even: wie in Nederland gaat dit serieus nemen?
Een vodje, geen wetenschap maar fantasierijke speculatie gebaseerd op onzin, biologische onmogelijkheden en niet‑causale casestudies.
Het antwoord was eigenlijk al duidelijk.
1/2
Een vodje, geen wetenschap maar fantasierijke speculatie gebaseerd op onzin, biologische onmogelijkheden en niet‑causale casestudies.
Het antwoord was eigenlijk al duidelijk.
1/2
February 10, 2026 at 2:48 PM
Ik dacht heel even: wie in Nederland gaat dit serieus nemen?
Een vodje, geen wetenschap maar fantasierijke speculatie gebaseerd op onzin, biologische onmogelijkheden en niet‑causale casestudies.
Het antwoord was eigenlijk al duidelijk.
1/2
Een vodje, geen wetenschap maar fantasierijke speculatie gebaseerd op onzin, biologische onmogelijkheden en niet‑causale casestudies.
Het antwoord was eigenlijk al duidelijk.
1/2
Reposted by Marc Veldhoen
Should one see?
First of all, getting a paper published is not just sending it, making a few changes, and moving on to the next one. It is frequent rejections, sometimes many times, delays, much more work to be done, and possibly rejection again. More experiments, etc.
1/5
First of all, getting a paper published is not just sending it, making a few changes, and moving on to the next one. It is frequent rejections, sometimes many times, delays, much more work to be done, and possibly rejection again. More experiments, etc.
1/5
February 9, 2026 at 3:10 PM
Should one see?
First of all, getting a paper published is not just sending it, making a few changes, and moving on to the next one. It is frequent rejections, sometimes many times, delays, much more work to be done, and possibly rejection again. More experiments, etc.
1/5
First of all, getting a paper published is not just sending it, making a few changes, and moving on to the next one. It is frequent rejections, sometimes many times, delays, much more work to be done, and possibly rejection again. More experiments, etc.
1/5
Yes, I am aware, also of the primary research and retractions. That is why I refer to it as a "contributing factor"; if it is causal, it is highly questionable, but it likely contributes, possibly as an additional consequence.
In this case, it is used as a POC.
In this case, it is used as a POC.
February 10, 2026 at 2:34 PM
Yes, I am aware, also of the primary research and retractions. That is why I refer to it as a "contributing factor"; if it is causal, it is highly questionable, but it likely contributes, possibly as an additional consequence.
In this case, it is used as a POC.
In this case, it is used as a POC.
De "vrijheidstrijders" zijn gelijk in oproer en zeer verbolgen. Wat ze zien in de spiegel is toch niet zo leuk.
Het kan niet je smaak zijn, het gebruik van ratten kan afgekeurt worden.... maar die spiegel die wordt voorgehouden zou er zwakker door zijn.
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Het kan niet je smaak zijn, het gebruik van ratten kan afgekeurt worden.... maar die spiegel die wordt voorgehouden zou er zwakker door zijn.
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February 10, 2026 at 2:31 PM
De "vrijheidstrijders" zijn gelijk in oproer en zeer verbolgen. Wat ze zien in de spiegel is toch niet zo leuk.
Het kan niet je smaak zijn, het gebruik van ratten kan afgekeurt worden.... maar die spiegel die wordt voorgehouden zou er zwakker door zijn.
2/2
Het kan niet je smaak zijn, het gebruik van ratten kan afgekeurt worden.... maar die spiegel die wordt voorgehouden zou er zwakker door zijn.
2/2
Vrijheid.
Het maken van een cartoon. Sarcasme, karikatuur, enz. Het aan de kaakstellen van mistanden.
Zoals deze van Joep Bertrams (Joep Bertrams). Het geeft de koers van de FvD aan die mensen toelaat met een dubieus extreem rechts verleden.
1/2
Het maken van een cartoon. Sarcasme, karikatuur, enz. Het aan de kaakstellen van mistanden.
Zoals deze van Joep Bertrams (Joep Bertrams). Het geeft de koers van de FvD aan die mensen toelaat met een dubieus extreem rechts verleden.
1/2
February 10, 2026 at 2:31 PM
Vrijheid.
Het maken van een cartoon. Sarcasme, karikatuur, enz. Het aan de kaakstellen van mistanden.
Zoals deze van Joep Bertrams (Joep Bertrams). Het geeft de koers van de FvD aan die mensen toelaat met een dubieus extreem rechts verleden.
1/2
Het maken van een cartoon. Sarcasme, karikatuur, enz. Het aan de kaakstellen van mistanden.
Zoals deze van Joep Bertrams (Joep Bertrams). Het geeft de koers van de FvD aan die mensen toelaat met een dubieus extreem rechts verleden.
1/2
These amyloid plaque–specific CD4+ CAR-T Cells increase in presence where needed and reduce dural amyloidosis in vivo (mouse). This also worked in a second model, transiently generating CAR T cells using mRNA transfection.
Nice work, but not in the clinic soon.
3/3
Nice work, but not in the clinic soon.
3/3
February 10, 2026 at 2:17 PM
These amyloid plaque–specific CD4+ CAR-T Cells increase in presence where needed and reduce dural amyloidosis in vivo (mouse). This also worked in a second model, transiently generating CAR T cells using mRNA transfection.
Nice work, but not in the clinic soon.
3/3
Nice work, but not in the clinic soon.
3/3
Chimeric antigen receptors (CARs) are a focus in the field of anti-cancer therapies. But, their potential use has expanded to autoimmunity and infection, and now AD. The authors generated a CAR that can recognise amyloid-b, in 5xFAD mice.
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February 10, 2026 at 2:17 PM
Chimeric antigen receptors (CARs) are a focus in the field of anti-cancer therapies. But, their potential use has expanded to autoimmunity and infection, and now AD. The authors generated a CAR that can recognise amyloid-b, in 5xFAD mice.
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Engineering chimeric antigen receptor CD4 T cells for Alzheimer’s disease
Using your own T cells, modified ton recognise one of the AD contributing factors; fibrillar forms of aggregated amyloid-β
www.pnas.org/doi/10....
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Using your own T cells, modified ton recognise one of the AD contributing factors; fibrillar forms of aggregated amyloid-β
www.pnas.org/doi/10....
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February 10, 2026 at 2:17 PM
Engineering chimeric antigen receptor CD4 T cells for Alzheimer’s disease
Using your own T cells, modified ton recognise one of the AD contributing factors; fibrillar forms of aggregated amyloid-β
www.pnas.org/doi/10....
1/3
Using your own T cells, modified ton recognise one of the AD contributing factors; fibrillar forms of aggregated amyloid-β
www.pnas.org/doi/10....
1/3
But the link, in multiple and very large studies, is very strong.
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February 10, 2026 at 10:43 AM
But the link, in multiple and very large studies, is very strong.
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Note that not all infections have this link, and some cause weightloss (HIV and Mtb are shown), and obesity only explains a part. Its link was enhanced during the COVID-19 pandemic.
BMI may not be the best proxy to determine metabiolic issues and self-reporting has biases.
5/6
BMI may not be the best proxy to determine metabiolic issues and self-reporting has biases.
5/6
February 10, 2026 at 10:43 AM
Note that not all infections have this link, and some cause weightloss (HIV and Mtb are shown), and obesity only explains a part. Its link was enhanced during the COVID-19 pandemic.
BMI may not be the best proxy to determine metabiolic issues and self-reporting has biases.
5/6
BMI may not be the best proxy to determine metabiolic issues and self-reporting has biases.
5/6
There are links with reduced T- and NK-cell function, altered neutrophil function, complement and adiponectin signalling, and diminished mucus clearance and lymphatic flow further compromise host defence. This is also an important confounder in many studies.
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February 10, 2026 at 10:43 AM
There are links with reduced T- and NK-cell function, altered neutrophil function, complement and adiponectin signalling, and diminished mucus clearance and lymphatic flow further compromise host defence. This is also an important confounder in many studies.
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Participants had no recent history of infection-related hospitalisations at baseline.
The associations of obesity and severe infection are very plausible. There are immune alterations linked to obisity and it causes low-grade inflamnmation, linked to reduced function.
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The associations of obesity and severe infection are very plausible. There are immune alterations linked to obisity and it causes low-grade inflamnmation, linked to reduced function.
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February 10, 2026 at 10:43 AM
Participants had no recent history of infection-related hospitalisations at baseline.
The associations of obesity and severe infection are very plausible. There are immune alterations linked to obisity and it causes low-grade inflamnmation, linked to reduced function.
3/6
The associations of obesity and severe infection are very plausible. There are immune alterations linked to obisity and it causes low-grade inflamnmation, linked to reduced function.
3/6
This is a very large study, 67 766 adults (mean age 42·1 [SD 10·8] years; 49 516 [73·1%] females, 18 250 [26·9%] males) from the Finnish cohorts and 479 498 adults (mean age 57·0 [SD 8·1] years; 261 084 [54·4%] females, 218 414 [45·6%] males) from UK Biobank.
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February 10, 2026 at 10:42 AM
This is a very large study, 67 766 adults (mean age 42·1 [SD 10·8] years; 49 516 [73·1%] females, 18 250 [26·9%] males) from the Finnish cohorts and 479 498 adults (mean age 57·0 [SD 8·1] years; 261 084 [54·4%] females, 218 414 [45·6%] males) from UK Biobank.
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Adult obesity and risk of severe infections: a multicohort study with global burden estimates
Adult obesity is a risk factor for infection-related hospitalisations and mortality across diverse pathogen types, causing ~1/10 infection-related deaths.
www.thelancet.com/jo...
1/6
Adult obesity is a risk factor for infection-related hospitalisations and mortality across diverse pathogen types, causing ~1/10 infection-related deaths.
www.thelancet.com/jo...
1/6
February 10, 2026 at 10:42 AM
Adult obesity and risk of severe infections: a multicohort study with global burden estimates
Adult obesity is a risk factor for infection-related hospitalisations and mortality across diverse pathogen types, causing ~1/10 infection-related deaths.
www.thelancet.com/jo...
1/6
Adult obesity is a risk factor for infection-related hospitalisations and mortality across diverse pathogen types, causing ~1/10 infection-related deaths.
www.thelancet.com/jo...
1/6
Reposted by Marc Veldhoen
The Children of Dilley
ProPublica went inside the immigrant detention center for families in Dilley, Texas. Children held there told us about the anguish of being ripped from their lives in the United States and the fear of what comes next.
www.propublica.org/a...
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ProPublica went inside the immigrant detention center for families in Dilley, Texas. Children held there told us about the anguish of being ripped from their lives in the United States and the fear of what comes next.
www.propublica.org/a...
1/2
The Kids Trump Sent to ICE’s Dilley Detention Center
ProPublica went inside the immigrant detention center for families in Dilley, Texas. Children held there told us about the anguish of being ripped from their lives in the United States and the fear of what comes next.
www.propublica.org
February 9, 2026 at 4:10 PM
The Children of Dilley
ProPublica went inside the immigrant detention center for families in Dilley, Texas. Children held there told us about the anguish of being ripped from their lives in the United States and the fear of what comes next.
www.propublica.org/a...
1/2
ProPublica went inside the immigrant detention center for families in Dilley, Texas. Children held there told us about the anguish of being ripped from their lives in the United States and the fear of what comes next.
www.propublica.org/a...
1/2
Reposted by Marc Veldhoen
‘Absolute hell’: Irishman with valid US work permit held by Ice since September
Seamus Culleton has been in a detention facility in Texas for nearly five months despite having no criminal record.
It can happen to anyone.
www.irishtimes.com/w...
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Seamus Culleton has been in a detention facility in Texas for nearly five months despite having no criminal record.
It can happen to anyone.
www.irishtimes.com/w...
1/3
‘Absolute hell’: Irishman with valid US work permit held by Ice since September
Seamus Culleton has been in a detention facility in Texas for nearly five months despite having no criminal record
www.irishtimes.com
February 9, 2026 at 4:05 PM
‘Absolute hell’: Irishman with valid US work permit held by Ice since September
Seamus Culleton has been in a detention facility in Texas for nearly five months despite having no criminal record.
It can happen to anyone.
www.irishtimes.com/w...
1/3
Seamus Culleton has been in a detention facility in Texas for nearly five months despite having no criminal record.
It can happen to anyone.
www.irishtimes.com/w...
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Thou shall not be indifferent.
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February 9, 2026 at 4:10 PM
Thou shall not be indifferent.
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2/2
The Children of Dilley
ProPublica went inside the immigrant detention center for families in Dilley, Texas. Children held there told us about the anguish of being ripped from their lives in the United States and the fear of what comes next.
www.propublica.org/a...
1/2
ProPublica went inside the immigrant detention center for families in Dilley, Texas. Children held there told us about the anguish of being ripped from their lives in the United States and the fear of what comes next.
www.propublica.org/a...
1/2
The Kids Trump Sent to ICE’s Dilley Detention Center
ProPublica went inside the immigrant detention center for families in Dilley, Texas. Children held there told us about the anguish of being ripped from their lives in the United States and the fear of what comes next.
www.propublica.org
February 9, 2026 at 4:10 PM
The Children of Dilley
ProPublica went inside the immigrant detention center for families in Dilley, Texas. Children held there told us about the anguish of being ripped from their lives in the United States and the fear of what comes next.
www.propublica.org/a...
1/2
ProPublica went inside the immigrant detention center for families in Dilley, Texas. Children held there told us about the anguish of being ripped from their lives in the United States and the fear of what comes next.
www.propublica.org/a...
1/2