Humanized Pig Center

In the past, researchers have taken human stem cells, inserted them in Severe Combined Immunodeficiency (SCID) mice and thus created mice composed of human tissue. Today, with their humanised pig model, Kim, Hong and colleagues have followed similar steps to generate humanised miniature pigs. The humanised pig they have developed is a mini pig composed of human biological matter - human cells, tissues and organs. By inserting individual-tailored human stem cells into SCID mini pigs, one could modify a humanised pig to a specific individual seeking medical testing. With these customised humanised mini pigs, preclinical trials could be carried out with particular patients in mind.
In order to create a SCID pig with human stem cells, the centre uses a recently developed genome editing technology called CRISPR/Cas9. 'This allows us to edit the genomes of the mini pigs according to desired traits,' outlines Hong. 'Genome-wide approaches as well as classic cell biology and biochemistry are used to evaluate outcomes.'
The novel SCID humanised mini pig could not only be used for preclinical testing but also for life-saving organ transplants in humans. Thousands of individuals around the world await organ transplantation, and everyday individuals on the waiting list die without having received their necessary transplant. With the widespread use of humanised pigs, these numbers could be drastically reduced.
In the early 1900s, scientists began to experiment with xenotransplantation, or the process of transplanting organs or tissues from one species to another. However, they learned that our immune systems would prevent these attempts from success. 'The first type of rejection is hyperacute rejection which happens within minutes, followed by acute rejection which occurs within a couple of days,' says Hong. 'In addition, there is slow and progressive rejection called chronic rejection, which happens within a couple of years. The immune rejections make the xenotransplantation difficult to use in regenerative medicine.' However, in the humanised pig project, the centre can produce human tissues and organs in the SCID pigs directly, allowing for better uptake of organ transplants in patients and less risk of rejection.
Work at The Humanized Pig Center is uniquely multidisciplinary and collaborative, leading to the most effective results. Their research team is composed of three groups and working closely together. Group One manages the production of pig models using classic breeding and embryo micromanipulation; Group Two produces human donor cells using stem cells and tissue engineering technologies; and Group Three focuses on characterisation of the donor cells and tissues produced in the SCID pigs using molecular, biochemical and epigenetic approaches.
The centre has also established relationships in the US, collaborating with Dr Randall Prather at University of Missouri and Dr Kiho Lee at Virginia Tech University.