The T cells, along with antibodies, are an integral part of the human immune response against viral infections due to their ability to directly target and kill infected cells. A Singapore study has uncovered the presence of virus-specific T cell immunity in people who recovered from COVID-19 and SARS, as well as some healthy study subjects who had never been infected by either virus.
https://medicalxpress.com/news/2020-07-scientists-uncover-sars-cov-specific-cell-immunity.html
Yes, I saw it in BBC and thanks for sharing here dear Dr Ijaz Durrani
.
Scientists still don’t know a lot about T-cells and Covid-19, but what they’ve learned is encouraging
Scientists don’t yet have data on long-term T-cells and memory B-cell response when it comes to SARS-CoV-2, but what they’ve seen so far is encouraging.
Crotty, Sette, and colleagues in June published a paper in the journal Cell looking at T-cell response in Covid-19 cases that did not require hospitalization.
“What we showed is that in average cases of Covid-19, where people got sick but didn’t have to go to the hospital, basically all of them made a CD4 T-cell [i.e., a helper T-cell] response,” Crotty says. “And most of them made a CD8 T-cell [i.e., a Killer T-cell] response. And so that looks pretty good.”
The big question about long-term immunity
The big question lurking behind all this science is: What is the right mix — both in number and type — of antibodies, T-cells, and B-cells that lead to lasting, robust immunity to SARS-CoV-2? For instance, it could be that you don’t need a very high concentration of antibodies in your blood to successfully fight off the virus. It could be that T-cells play a bigger role in protection.
https://www.vox.com/2020/7/22/21324729/getting-covid-19-twice-immunity-antibodies-vaccine-herd-immunity
It would be better to try for immunity development by vaccination not by infecting only.
If you get back to the basics. The failed immunity before severely affecting the host is due to the fact that virus doesn't infect the blood. It takes its time to enter the blood stream. They need to pass that 14 day period to see some thing in blood. In a study published in JAMA, only 3 people out of 240 who were positive to Corona were having it in blood. And if the virus doesn't reach the blood we don't find immunity. Lungs have their own phagocytes or antigen presenting cells. They do not have access to helper cells for antibody generation. And in a recent paper in nature (was retracted ) stated that virus can infect t lymphocytes even with out ACE2. It wasn't retracted based on weather it could infect t lymphocytes but the facs analysis. And immunity or antibody or cd8 cells reaching to gut or lungs is quite impossible unless the barrier is broken.
https://jamanetwork.com/journals/jama/fullarticle/2762997
This is the link to the JAMA paper. Correction in the numbers. It's 3 out of 307
Dr Muhammed Ashraful Alam
There has been exciting, further work on this subject:
Robust SARS-CoV-2-specific T-cell immunity is maintained at 6 months following primary infection
Preprint Robust SARS-CoV-2-specific T-cell immunity is maintained at ...
Could this be the way forward?