The Protective Immunity from T cells to COVID-19 in Health workers study (PITCH) – conducted in collaboration with the universities of Liverpool, Sheffield, Newcastle and Birmingham with support from the UK Coronavirus Immunology Consortium – examined how the immune system responds to COVID-19 in 78 healthcare workers who had experienced either symptomatic or asymptomatic disease (66 vs 12). An additional eight patients who experienced severe disease were included for comparison.
Blood samples were taken monthly from one to six months post infection to examine different elements of the immune response. This included different types of antibodies – such as Spike-specific and Nucleocapsid-specific antibodies produced to target different parts of the virus, alongside B cells that manufacture antibodies and keep the body’s memory of the disease, and several types of T cell.