It has become imperative to control the SARS-CoV-2 virus during its acute phase of infection to reduce the disease severity. A new research at the La Jolla Institute for Immunology was conducted to investigate the presumed reasons behind increasing risk of people of 65 years old and above getting chronically ill with the novel coronavirus.
Study confirms the speculations that a specific type of immune cells called T-cells play a significant role, far better than antibodies in controlling the acute phase infection and reducing the diseases severity with Covid-19. Research findings were published in Cell, in form of journal pre-proof.
A multi-layered, virus-specific #immune response is important for controlling the #virus during acute phase of infection & reducing #Covid19 disease severity, with most evidence pointing to a much bigger role for #TCells than #antibodies#pandemic #study https://t.co/uFXBZeh9HU
— Dr Sandeep Ghiya (@sandeepghiya) September 17, 2020
Most of the coronaviruses are not life-threatening, even majority cases of the SARS-CoV-2 infections are not severe. However, a significant proportion of patients who are 65 and above, and have pre-existing medical conditions, needed hospitalization and are commonly subjected to increase fatalities.
Ever since the outbreak of SARS-CoV-2, based on the scientific data, it is believed that it is the acute phase of Covid-19 infection during which immune system exacerbate and predispose more harm than any good. Therefore, the current research findings implicate that vaccine candidates must be used to produce immune system response broadly that includes antibodies, helper and killer T cells to ensure protective immunity.
The study explains the immune response elicited in response to the invading SARS-CoV-2 and is manifested by inflammation. As a first line of defense, innate system gets activated, during which inflammation levels gets augmented under diseased conditions. Following, within days, the long term adaptive immune system gets activated where immune cells are released to fight the virus including antibodies. These include helper T cells (Th) which helps B cell to manufacture protective antibodies and killer T cells (CTL) which seek out virus-infected cells and kill them.
The research team recruited 50 patients with confirmed Covid-19 infections and analyzed all three types of immune responses generated by the long term adaptive immune responses; SARS-CoV-2 specific antibodies, helper and killer T cells. The elucidative research data indicated that during acute phase of infection, in adaptive immune response, there were some lacking neutralizing antibodies found along with varied number of helper and killer T cells.
The senior author Shane Crotty, Ph.D., professor in LJI’s Center for Infectious Disease and Vaccine Research, talked about significance of research findings on their university news press,“Our observations could also explain why older COVID-19 patients are much more vulnerable to the disease. With increasing age, the reservoir of T cells that can be activated against a specific virus declines and the body’s immune response becomes less coordinated, which looks to be one factor making older people drastically more susceptible to severe or fatal COVID-19.”