The adaptive immune system has evolved to provide a more versatile and highly target-specific defense with an ability to distinguish very subtle differences in the make-up of infectious agents. But the adaptive immune system is slow and can take several days before two key cell types—B cells and T cells—are brought into play.T cells are further grouped into two sub-types, CD4+ and CD8+ cells. CD4+ are helper T cells that help the activity of other immune cells by releasing cytokines. The cytokines prime the maturation of B cells, which become plasma cells and produce antibodies to neutralize the pathogen. T cells were found in the recovered as well as uninfected people suggesting a previous infection with corona viruses causing common cold could provide protection also.It remains unclear whether these defenses can protect people from a reinfection with SARS-CoV-2, and, if so, for how long.A key part of the immune system, T cells can recognize fragments of viruses. When the cells identify a viral protein, helper T cells release chemical signals that trigger other parts of the immune system to kick into gear. Others, called killer T cells, hunt down and kill infected cells.It’s “tempting to speculate” that the cells could help people never exposed to the new corona virus, the researchers write. But to know for sure, experts would need to test T cells from someone both before and after a SARS-CoV-2 infection.
A good piece going into the origin of immunity at the cellular level.The way the innate and adaptive immune systems act and improve to play key role in fighting infections is covered well.The article would have covered in my opinion, on the factors like types of food,lifestyle etc.that help improving the immune system.This is because, we find and hear so many claims of formulations promising on immunity boosting .Ultimately the success depends on the immunity of the individual and if this can be be boosted up, the job is done..Also if the antibody level in asymptomatic individuals is lesser relative to symptomatic cases, how come the lethality of the virus is more pronounced in the latter needs to be examined.Targeting the genes once immunity is accepted as hereditary, may be a part of future management of critical infections and such a breakthrough in genetic engineering may be a panacea !