Cape Town company joins global efforts to develop plant-based Covid-19 test kits

5th May 2020 By: Donna Slater - Creamer Media Contributing Editor and Photographer

Cape Bio Pharms, a spin-off company of the Biopharming Research Unit at the University of Cape Town, has partnered with international biotechnology companies to address the international problem of accessibility to affordable reagents and rapid Covid-19 serology testing, with the launch of its Plants Against Corona initiative.

Using plants to produce the antigens and antibodies required for rapid diagnostic test kits, the initiative aims to develop a faster, broader and more effective Covid-19 testing response, in South Africa and internationally.

Cape Bio Pharms co-founder Tamlyn Shaw says the company is working towards developing antigens and antibodies for late-stage serology diagnostic tests that detect antibodies in a patient’s blood.

“This is unlike most diagnostic Covid-19 tests, which look for genetic material to see if someone is currently infectious.”

Using a distant species of the tobacco plant – Nicotiana benthamiana – Cape Bio Pharms has produced proprietary plant-based antigens and antibodies against Covid-19. 

Under the Plants Against Corona partnership, Cape Bio Pharms sourced the gene sequences for SARS-CoV-2 (the virus that leads to Covid-19), to develop the antigen constructs used to infiltrate the plants, turning them into highly effective bioreactors. These constructs are being made available to the Plants Against Corona network to speed up and enhance production of SARS-CoV-2 antigens internationally.

Cape Bio Pharms notes that a major shortcoming in how the world is testing for Covid-19 is that public health authorities currently have no means to determine whether patients have recovered and are possibly immune.

Shaw recommends that serology testing must be done in conjunction with polymerase chain reaction-based testing, which detects Covid-19 at the genetic level.

“Once a person is producing antibodies, we know they have recovered, but not necessarily developed immunity to the virus,” she says.

However, serology testing allows for continuous assessment of those who have resumed work and social care duties, notes Shaw. “The speed and accessibility of these test kits will enable public health authorities to consistently test for SARS-CoV-2."

Global partners in the network include Canadian company Plantform and UK-based Leaf Expressions, both of which will assist with scaling up production capacity of the antigens to ensure that the initiative is able to meet global demand.

Academic partners include US-based Plantvax and the Department of Applied Genetics and Cell Biology at the University of Natural Resources and Life Sciences, in Vienna. These parties will be using the genetic constructs for their own research and development to further grow the community.

Quebec-based vertical farming equipment design company, Inno-3B, aims to assist the Plants Against Corona initiative in rapidly scaling up its plant-growth capacity.

Shaw says Cape Bio Pharms has already sent samples of its antigens to local test kit manufacturers who are validating its proteins externally. “These proteins have passed our own internal validations and tests and one of the test kit manufacturers has confirmed our protein has been clearly recognised by antibodies against the virus.”

Besides reshaping the Covid-19 testing landscape, the collaboration has a strong research focus. “We want as much intellectual property as possible to come into the network, which all partners can use under licence agreements,” she says.

“Producing and sharing knowledge and working together on improving existing data boosts capacities and unlocks new opportunities. This is crucial for a quick and broad response to Covid-19, which is impossible to achieve when working in silos,” says Shaw.

The work done now will not just benefit the present, Shaw notes, explaining that building global networks today helps the world prepare a first line of defence to the next pandemic. “Taking history into consideration, we can be sure of one thing – this will not be the last global disease outbreak.”