What is protective immunity?

The WHO reiterated on April 18th that antibodies do not indicate immunity. There is a critical lack of knowledge on the humoral immune response and what it means with respect to A) protection from disease or recurrent disease, B) viral clearance, C) disease severity and prognosis, and D) durability of protection. For example, there is a dichotomy of different types of antibody responses: protective versus disease triggering ones. Current assays cannot distinguish these.

To address this we are applying a cutting edge, innovative, high-throughput platform to characterise in fine detail the types of antibody responses and the humoral effector mechanisms that protect from SARS-CoV-2, and to distinguish from the responses that lead to the pro-inflammatory and complement responses associated with life-threatening COVID-19.


The tests and assays we are developing are fundamentally needed to:

  • Accurately provide evidence to inform clinical and public health decisions, 

  • Guide intervention therapies, 

  • Facilitate vaccine development, and

  • Standardised clinical vaccine trial endpoints.

See an early output here.

We will answer critical questions such as:

  • What are the antibody response differences between individuals who have mild SARS-CoV-2 infection and high risk patients who progress to life threatening disease?

  • How soon does someone infected and recovered achieve immunity, and how long does it last for?

  • Will pre-existing antibodies be protective in different age-groups, or pre-disposing for more severe disease (e.g. ADE)?


As part of our key deliverables, we will:

  • Create the first high impact key “protective” immune response data, as standardised assays and new diagnostic tests are developed. 

  • Develop assays that distinguish successful protective immune responses from ones that are associated with severe disease. 

  • Widely share standards, assays and SOPs to PHE, NHS and other diagnostic labs across the UK.

  • Rapidly provide robust data for evidence-based decisions. 

  • Provide tests and data to define protective immunity as benchmarks for clinical trials of vaccines and therapeutics.

We will deliver tests, SOPs, reference standards for assays, and hard data for evidence-based decisions for the NHS, WHO and FDA that current technology is unable to provide. This is invaluable for clinical management of exposed or infected NHS staff and the public. We will provide assay standards as assay reference controls coordinated with the FDA and WHO-established International Standards, enabling national and worldwide calibration of the data generated to an International Unit for assay comparisons and harmonisation. This is critically important as this will provide highly specific assays discriminating protective (vs. harmful) antibody levels for vaccine and antibody therapeutic potencies.