POST Online Media Lite Edition


Transplantation of organs from pigs to humans one big step closer after Paul-Ehrlich-Institut's findings

Christian Fernsby |
Intensive research is being carried out to enable the transplantation of organs from specially bred pigs to humans.

Article continues below

However, the pig genome contains the genomes of various endogenous retroviruses (PERV-A, B and C) that could potentially cause infectious diseases.

A research team at the Paul-Ehrlich-Institut has demonstrated in the Yucatan miniature pig breed (haplotype SLA D/D) that the retrovirus PERV-C could be reproductive and therefore infectious.

The identification of the PERV-C genome now makes it possible to remove the PERV-C retrovirus genome from the pigs' genome via gene editing (Journal of Virology, 8 March 2023).

Currently more than 8,500 patients are on the waiting list for organ donation in Germany. Organs for transplantation are so scarce that patients often have to wait a very long time for a suitable organ.

In order to remedy this situation, many years of research have been conducted to explore the possibility of using specially bred pigs as organ donors.

In 2022, the first transplant of a genetically modified pig heart was carried out in the US on a patient for whom no other therapies were available and who was not eligible for a regular organ transplant. The patient experienced complications 49 days later and died 60 days after transplantation. The causes of the organ failure are still being investigated.

When transplanting an organ from a pig to a human (xenotransplantation) there is a risk that endogenous pig retroviruses – viruses whose genome is anchored in the donor animal's genome, namely in the genome of each cell of the pig breed – could be transmitted to the recipient in the form of reproductive virus particles and could cause diseases.

The risk is especially valid in view of the fact that transplant patients receive drugs that inhibit the immune system (immunosuppression) in order to prevent organ rejection.

Due to the anchoring of the retrovirus genomes in the genome of each of the pig's cells, it has not been possible to remove the retroviruses or breed donor pigs without retrovirus genomes.

Endogenous pig retroviruses are called PERV (porcine endogenous retroviruses). They are closely related to the retroviruses that can cause leukemia and immunodeficiency diseases in mice, cats or gibbons.

It is therefore suspected that after transmission to humans, PERV could also trigger these diseases in these people.

It has been shown that two PERV classes, PERV-A and PERV-B, can not only infect pig cell lines in vitro in laboratory cell culture experiments but are also capable of infecting and further multiplying in cell lines of different species, including humans.

The retroviruses are polytropic, which means PERV-A and PERV-B can overcome species barriers and potentially infect humans after transmission.

In contrast, PERV-C retroviruses primarily infect pig cells, but not human cells.

However, it has been observed in laboratory experiments that PERV-C can recombine with PERV-A, resulting in PERV-A/C, which can infect human cells. Compared to PERV-A and PERV-B, PERV-A/C actually multiplies better in laboratory cell cultures.

A pig breed that seems particularly suitable for organ donation is the Yucatan miniature pig. The wild types (ancestors) of this pig were brought to Boston, USA, from Yucatan, Mexico, for breeding 60 years ago.

The breed "haplotype SLA D/D" was generated in Boston over several years with a view to using the animals as organ donors for xenotransplantation.

This breed has neither a fully functional PERV-A genome nor a fully functional PERV-B genome, so that no infectious or reproducible retrovirus particles are formed. Haplotype SLA D/D pigs can indeed be PERV-C genome carriers, but it had been hitherto assumed that the resulting PERV-C retrovirus particles are not replication-competent (reproductive) and not infectious, provided that the pigs are not infected with PERV-A.

A research team at the Paul-Ehrlich-Institut headed by Dr Ralf Tönjes, research team leader in the Transfusion Medicine, Cell Therapy and Tissue Preparations Section, investigated the question of whether PERV-C itself might also be competent in replication.

In the characterisation of PERV-C from cells of the pig breed haplotype SLA D/D, they found that in vitro PERV-C is quite capable of replication and is infectious, i.e. it can reproduce in cell culture.

This would pose a risk for transplants. The good news is that since these PERV-C genomes only occur once in the pig genome, a knockout, a switching off of these PERV-C loci, would be possible using genome editing, i.e. the targeted modification of the pig's DNA.

Thus, there would be no risk of transmission of PERV during xenotransplantation of organs from PERV-C knockout pigs from the haplotype SLA D/D.

The current findings provide valuable information that serves as another step closer to suitable donor animals for xenotransplantation. The Paul-Ehrlich-Institut is responsible for scientific advice on and approval of clinical trials of xenogeneic drugs in Germany.

What to read next

Germany approves third clinical trial of coronavirus vaccine
The number of kidney discards in U.S. is increasing
Possible new ways of preventing or treating organ transplant rejection

Flooding concerns in Puerto Rico; thunderstorms across southeast U.S.

The main weather feature and focus for showers and thunderstorms through this weekend will be a cold front progressing across the East and stalling between the Southeast and southern Texas.


Concept Medical announces enrollment of first patient in "MAGICAL-ISR" ide study in U.S.
U.S. oil rig count up by 5 to 511
Rhode Island Governor, State Police promote safe travel across Washington Bridge
Governor Abbott met with Samsung executives to discuss billions invested in Texas


California: Nearly 500 arrests, 160,000 stolen goods recovered in just 3 months

Romania: EPPO probes public officials in investigation into €160 000 fraud involving employment funds
EPPO: 3 convicted of evading €3.1 million in customs duties on imported e-bikes
Romania: EPPO conducted searches in investigation into €1.7 million fraud involving irrigation systems
U.S.: Pacific storm over west
4.8 magnitude earthquake rattles New Jersey and New York


U.S. drillers cut oil and gas rigs to 620

Australia: East coast gas surplus expected in Q3 2024
Kuwait-Saudi rail link to be ready by 2028, says report
Cambodia approves investment projects worth $2.2 in Q1
Venice to charge day trip tourists 5 euros
Commission opens two in-depth investigations in solar photovoltaic sector

Trending Now

Coca-Cola Company to create approximately 250 new jobs in Town of Webster

Governor Abbott met with Samsung executives to discuss billions invested in Texas

Concept Medical announces enrollment of first patient in "MAGICAL-ISR" ide study in U.S.

Egypt to establish free zone for yachts along Red Sea coast


Egypt to establish free zone for yachts along Red Sea coast

UK Exports Minister visits Latin America to boost trade and unlock billions worth of exports
Argentina, Brazil in talks to reverse Bolivian gas pipeline amid shortage
Trudeau offers $6 billion to provinces to build housing
€1 billion Greek State aid measures to support renewable energy generation and storage projects
North Carolina reaches electric vehicle registration goals two years early

Today We Recommend

Egypt to establish free zone for yachts along Red Sea coast


Nokia Q1 sales down

UnitedHealth Q1 $99.8 billion

Johnson & Johnson Q1 earnings $5.3bn


Coca-Cola Company to create approximately 250 new jobs in Town of Webster

99 Cents Only Stores to close all 371 stores
Alaska Airlines says Boeing paid $160 mln for 737 Max 9 grounding
Lindsay announces agreement to acquire minority interest in Pessl Instruments
Saint-Gobain to acquire Bailey for $650 million
Farmers Mutual Hail to acquire Global Ag from AXA XL


MainStreaming appoints Tassilo Raesig as COO

BioArctic AB proposes for election board members and chairperson
TerraPay names Marco Boldini as EVP and global head of governmental affairs
Farmers Insurance appoints John Griek as CFO
PA Media Group appoints Emily Shelley as new CEO
BioNTech appoints Annemarie Hanekamp as chief commercial officer


Slovenia's economy expected to grow 0.9 pct in Q1

Italy faces deficit infringement procedure
Real GDP increased in all 50 U.S. states
Inflation continues to decline in Germany
UK house prices log unexpected fall
South Korea's FDI logs double digit growth in Q1


Nokia Q1 sales down

UnitedHealth Q1 $99.8 billion
Johnson & Johnson Q1 earnings $5.3bn
Dollarama Q4 sales increased 11.3%
Conagra Brands Q3 sales decreased 1.7%
Liebherr finished 2023 business year with record revenue of €14,042 million


Micromanaging is the worst enemy of efficiency and teamwork

Niger set to monetize massive gas reserves through Saharan natural gas pipeline
Putting the brakes on EV folly that choked the market
Oil discovery in Kavango Basin may mean huge benefits for Namibians
Cape Town and Dubai battle over Africa's energy future
Is America going to lose its superpower status?


FAO Food Price Index rises in March

Australia grants license for GM bananas amid Fusarium Wilt TR4 concerns
Indian government allows exports of 10,000 tons of onions to UAE
Analytical survey: Sales of agricultural lands in Ukraine up 50% in February
Decline in Norwegian seafood exports in Q1
Tanzania's first fishing harbor to be completed in 2025


Study finds workers misjudge wage markets

Some organizations may need to expand their hierarchical structures earlier than others
Study finds there's right way and wrong way to deliver negative feedback in workplace
Allyship is critical and its needs appreciation
Generating 'buzz' about new products can influence their success
Hiring 'problem directors' can knock up to 64% off firm's value


HSBC pays penalties for alleged breaches of Consumer Data Right rules

Sanofi to settle thousands of Zantac cancer lawsuits
Former asset manager and board member of Geneva private bank referred to Swiss Federal Criminal Court
South Africa: SAP ordered to pay SIU $26m over 'invalid' Eskom contracts
Former Steinhoff director appears in court for $1.1b fraud, racketeering
Genesis agrees to pay $21 million penalty to settle SEC charges



Buna channels, an unreal and beautiful part of Bosnia and Herzegovina

JW Marriott unveils Mindful Haven with opening of JW Marriott Hotel Nairobi
Sotheby's Sports Week returns with fantastic artifacts
Red Roof properties open in Michigan
Treyam, your premier lagoon destination in Saudi Arabia
San Francisco: SkyStar wheel on Fisherman’s Wharf to stay for another 18 months


2025 Chevrolet Equinox stands apart with fresh looks and capability

Hill Helicopters HX50, luxury in the sky
Opel Movano becomes fully equipped camper van
Porsche Panamera, new hybrid variants
Dodge Charger, 670 horsepower of electric
Pagani Huayra R Evo, 900 hp from 770 Nm


Cold night, hot fire pit, cool entertainment

Embellish your home with PVC panels
You'll have to hurry if you want one of 20 new Louis Vuitton watches
Luxury duvet looks good, fells good and keeps you healthy
Vacheron Constantin, watches for life and more
Schüller kitchens, where functionality marries design


reMarkable 2, monochrome tablet for your thoughts and your eyes

OnePlus Ace 3V, first with Snapdragon 7 Plus Gen 3
ASUS Zenfone 11 Ultra, flagship with a reason
Samsung Galaxy S24 is photography powerhouse
Casette tapes are making a big comeback, and so are portable players
Neumann TLM 103, standard microphone for both voice and music


India launches first home-grown gene therapy for cancer

UK scientists win funding for 'cancer detecting' Lollipops
State to cover rare disease treatment costs in Bulgaria
Type 1 diabetes patients in England to receive 'artificial pancreas' as medication
Pilot study shows ketogenic diet improves severe mental illness
Texas reports possibly U.S. first human case of bird flu linked to cattle


Rare species of wild bees discovered in Berlin

SLAC completes construction of largest digital camera ever built for astronomy
Solar eclipse next week in U.S., Mexico and Canada
Gravitational waves may have made human life possible
Astronomers unveil strong magnetic fields spiraling at the edge of Milky Way's central black hole
Scientists on hunt for evidence of quantum gravity's existence at South Pole