Dr Able Lawrence🦉MD DM Profile picture
Prof Clinical Immunology & Rheumatology; Foodie Birder Photography Axiology Metaphysics #Lithium #Battery $TSLA #RenewableEnergy #EvoBio #COVID2019 #Wine
26 Aug
Germinal Centre defects in severe COVID19 patients who died cripples effective antibody response. It probably explains why it takes upto 4-5 weeks (incubation upto 2, then 2-3) for antibodies to form. 10% produce no antibodies at all. #CovidImmunity
sciencemag.org/news/2020/08/c…
Short lived nature of the antibody response after COVID19 infection makes dreams of Herd immunity from natural infections a mirage if ever it was even a thing. OTOH, vaccines "may" produce long lived antibodies, particularly with the RNA vaccines.
sciencemag.org/news/2020/08/s…
Defects in Germinal center formation explains the short duration and/or lack of effective antibody response in COVID19. Most antibodies are derived from non-GC Bcells. TFh differentiation defects underlie the lack of Bcl6+ TFh & Follicular Bcells. Bodes poorly for Herd immunity.
Read 7 tweets
14 May
Asians & others with darker skin living in Northern latitudes are prone to Vitamin D Deficiency? Severe COVID19 males had lower vitamin D levels. (Females take more supplements) Vitamin D plays key roles in cardiovascular & immune systems 1/n #VitaminD
blogs.scientificamerican.com/observations/a…
Vitamin D regulates the expression of PLC-γ1 in naive T cells & is key to T cell responsiveness in humans. Poor primary T cell response can affect immune responses to viral infections including influenza & coronaviruses. 2/n @Ms_Aflatoon #VitaminD
nature.com/articles/ni.18…
Vitamin D necessary for IFN-γ–induced antimicrobial peptide cathelicidin expression, autophagy, phagosome-lysosome fusion, and antimicrobial activity crucial to TB & leprosy immunity. Before antibiotics sunlight was the only treatment for tuberculosis 3/n
stm.sciencemag.org/content/3/104/…
Read 10 tweets
20 Apr
@nntaleb There are sufficient mechanistic studies to believe there could be a synergy between Zinc and Hydroxychloroquine.
Zinc has activity against multiple virus families including coronavirus.
Hydroxychloroquine is a Zinc chelator and potentiates Zinc effects. Will post references 1/n
@nntaleb Zn2+ Inhibits Coronavirus and Arterivirus RdRP RNA dependent RNA Polymerase Activity In Vitro and Zinc Ionophores Block the Replication of These Viruses in Cell Culture 2/n
journals.plos.org/plospathogens/…
@nntaleb Zinc ionophores inhibit other RNA viruses such as Dengue Virus as well. So this is a generic thing about RNA viruses. RdRp enzymes are structurally conserved across viral taxa.
frontiersin.org/articles/10.33…
Read 7 tweets
18 Mar
This is a thread on use of drugs for #COVID19
Hydroxychloroquine (Lupus, RA) Lopinavir/Ritonavir (HIV/AIDS) Remdisivir and Favipiravir (Ebola) and Camostat (Pancreatitis, Japan) are drugs that seem to have activity against SARSCov2
Some of these are used on Emergency Basis. 1/n Image
Potent nucleoside antiviral drug from Emory University shows broad spectrum activity against corona viruses including Remdisivir resistant strains. Acts by targeting RdRp to increase RNA mutation rates. @EmoryUniversity #EIDD2801 #COVID19
#coronavirus 1/n
news.emory.edu/stories/2020/0… ImageImage
Promising broad spectrum antiviral agent #EIDD2801 is active against #Remdisivir resistant strains. Indeed such mutations increase susceptibility which augurs well for combination use. It’s a prodrug gets converted to #EIDD1931 & increase mutations.
2/n
biorxiv.org/content/10.110…
Read 4 tweets