1 Introduction

The global shortage of human donor organs for transplantation is a critical issue, with thousands of patients on waiting lists and many succumbing to organ failure before a suitable donor is found. Xenotransplantation, particularly using pigs as organ donors, has emerged as a promising solution to the organ shortage crisis (Lin, 2024). Pigs, in particular, are considered ideal candidates for organ donation due to their anatomical and physiological similarities to humans, as well as their high reproductive rates and relatively low maintenance costs (Denner, 2018). The potential of pigs as organ donors could significantly alleviate the organ shortage crisis, providing a sustainable and scalable source of transplantable organs.

Despite the promising potential of pigs as organ donors, xenotransplantation carries significant risks, primarily due to the transmission of porcine pathogens. Porcine endogenous retroviruses (PERVs), which are integrated into the pig genome, pose a notable risk as they have the potential to infect human cells (Denner, 2021). Additionally, other porcine viruses such as porcine cytomegalovirus (PCMV) and porcine circovirus 3 (PCV3) have been shown to reduce the survival time of xenotransplants and may contribute to adverse outcomes in recipients (Denner, 2022). The transmission of these pathogens could lead to serious health complications, making it imperative to address these risks to ensure the safety of xenotransplantation.

The aim of genetic modifications in pigs for xenotransplantation is to enhance the biosafety of transplantable organs by eliminating or mitigating the risks posed by porcine pathogens. Advances in genome engineering technologies, such as CRISPR/Cas, have enabled the inactivation of PERVs in pigs, significantly reducing the risk of cross-species virus transmission (Niu et al., 2020). Additionally, genetic modifications can address other barriers to successful xenotransplantation, such as immune rejection, inflammation, and coagulative dysfunctions, by optimizing the expression of genes involved in these processes (Niu et al., 2020). These modifications, combined with effective immunosuppressive regimens, hold the potential to make xenotransplantation a viable and safe option for addressing the organ shortage crisis. The significance of these advancements cannot be overstated, as they pave the way for clinical trials and the eventual widespread adoption of xenotransplantation, offering hope to countless patients in need of life-saving organ transplants.

1 Background on Porcine Pathogens

1.1 Common porcine pathogens that pose risks in xenotransplantation

Porcine pathogens present significant challenges in the field of xenotransplantation, where pig organs are transplanted into human recipients. Among these pathogens, porcine endogenous retroviruses (PERVs) are of particular concern. PERVs are integrated into the genome of all pigs and have the potential to infect human cells, posing a zoonotic risk (Denner, 2022). Other notable pathogens include porcine cytomegalovirus (PCMV), porcine roseolovirus (PCMV/PRV), and porcine circovirus 3 (PCV3), which have been observed to transmit during xenotransplantation procedures (Denner, 2022).

1.2 Mechanisms of pathogen transmission from pigs to humans

The transmission of pathogens from pigs to humans during xenotransplantation can occur through several mechanisms. PERVs, being integrated into the pig genome, can be transmitted through the transplanted organ or tissue. These viruses are capable of infecting human cells, although no transmission has been observed in clinical trials involving pig islet cells (Denner, 2021). Other viruses, such as PCMV/PRV and PCV3, have been detected in recipients of pig heart transplants, indicating that these viruses can be transmitted through the transplanted organ (Denner, 2022). The transmission of these viruses can lead to significant complications, including reduced survival time of the xenotransplant (Denner, 2022).

1.3 Historical cases and lessons learned from previous xenotransplantation attempts

Historical attempts at xenotransplantation have provided valuable insights into the risks and challenges associated with porcine pathogens. In early clinical trials, no transmission of PERVs was observed in diabetic patients receiving pig islet cells (Niu et al., 2020). However, preclinical trials involving the transplantation of pig hearts into baboons revealed the transmission of PCMV/PRV and PCV3, which significantly reduced the survival time of the xenotransplants. The first pig heart transplantation into a human patient also resulted in the transmission of PCMV/PRV, potentially contributing to the patient's death (Denner, 2021). These cases highlight the importance of rigorous screening and the development of strategies to mitigate the risk of pathogen transmission in xenotransplantation.

2 Genetic Modifications to Enhance Biosafety

2.1 Overview of genetic engineering techniques

Genetic engineering has revolutionized the field of xenotransplantation, offering innovative approaches to eliminate porcine pathogens and enhance the biosafety of transplantable pig organs. Among the most prominent techniques are CRISPR/Cas9 and TALENs (Transcription Activator-Like Effector Nucleases). Techniques such as CRISPR/Cas9 have enabled precise modifications of the pig genome to reduce immunogenicity and enhance compatibility with the human immune system (Zhang, 2024). CRISPR/Cas9, a groundbreaking gene-editing tool, allows precise alterations to the pig genome by utilizing guide RNA to direct the Cas9 enzyme to specific DNA sequences, where it induces double-strand breaks that are repaired, resulting in gene disruption or modification. This technique is highly efficient, cost-effective, and versatile, making it ideal for targeting multiple genes simultaneously (Zheng et al., 2022). TALENs, on the other hand, function through engineered proteins that bind to specific DNA sequences and induce cuts, leading to gene modifications. Although TALENs are highly specific and effective for single gene edits, they are generally more labor-intensive and costly compared to CRISPR/Cas9. Both techniques have been instrumental in advancing genetic modifications aimed at reducing pathogen transmission risks in xenotransplantation (Ryczek et al., 2022).

2.2 Specific genes and pathways targeted to eliminate porcine pathogens

Targeting specific genes and pathways has been crucial in the effort to eliminate porcine pathogens from transplantable organs. One of the primary targets is the porcine endogenous retroviruses (PERVs), which are integrated into the pig genome and pose significant zoonotic risks. Using CRISPR/Cas9, researchers have successfully inactivated multiple copies of PERVs, significantly reducing the potential for cross-species viral transmission (Tanihara et al., 2019). Another critical target is the porcine cytomegalovirus (PCMV), which can adversely affect the survival of transplanted organs. Genetic modifications have been applied to enhance the pig's antiviral response, reducing the replication and transmission of PCMV (Perleberg et al., 2018). Additionally, pathways involved in immune evasion and inflammation have been modified to improve the compatibility of pig organs with human recipients. For instance, genes responsible for the expression of alpha-gal, a sugar molecule that triggers hyperacute rejection in humans, have been knocked out to prevent immune responses against pig organs.

2.3 Case studies of successful genetic modifications reducing pathogen loads

Several case studies highlight the success of genetic modifications in reducing pathogen loads and enhancing the biosafety of porcine organs. One study demonstrated the use of CRISPR/Cas9 to produce triple gene-knockout (TKO) pigs, targeting GGTA1, CMAH, and β4GalNT2. These modifications resulted in the elimination of major xenoantigens, significantly reducing human IgG/IgM binding and immunogenicity without affecting the physical properties of the porcine pericardium (Zheng et al., 2018). Another study utilized cytosine base editors to inactivate PERVs in pig cells, achieving approximately 10% complete inactivation of PERVs without causing DNA double-strand breaks or cytotoxic effects, thus offering a safer strategy for generating PERV-knockout pigs (Figure 1) (Zheng et al., 2022). These advancements underscore the potential of genetic engineering in creating safer and more compatible pig organs for xenotransplantation.

Zheng et al. (2022) investigated the efficiency of base editing in the PERV (porcine endogenous retrovirus) genome using the MAIO-epiCBE system. Their experimental approach included transfecting ST cells with the editing system, followed by selection and Sanger sequencing to identify genomic modifications. The study demonstrated that the MAIO-epiCBE system effectively induced base substitutions at multiple target sites within the PERV genome. This was confirmed by sequencing data, which revealed significant base conversion rates, marked by red arrows, across various sgRNA target sites. The results indicated successful base editing at high efficiency, producing amino acid changes and introducing stop codons at specific positions. These findings underscore the potential of MAIO-epiCBE for precise genome editing in PERV, offering a promising tool for future biotechnological applications in the pig-to-human xenotransplantation field.

3 CRISPR/Cas9 in Eliminating Porcine Endogenous Retroviruses (PERVs)

3.1 Mechanism of CRISPR/Cas9 and its application in targeting PERVs

The CRISPR/Cas9 system is a revolutionary genome-editing tool that allows for precise modifications of DNA sequences. It consists of two key components: the Cas9 enzyme, which acts as molecular scissors to cut DNA, and a guide RNA (gRNA) that directs Cas9 to the specific DNA sequence to be edited. In the context of eliminating PERVs, CRISPR/Cas9 can be designed to target and disrupt the PERV pol genes, which are essential for viral replication and integration into the host genome. This approach has been successfully applied to create PERV-inactivated pig cell lines, such as the PK15 clone 15, which showed impaired viral particle production and non-infectious virions (Godehardt et al., 2019).

3.2 Experimental evidence and outcomes of perv inactivation

Several studies have demonstrated the effectiveness of CRISPR/Cas9 in inactivating PERVs. For instance, the PK15 clone 15 cell line, which underwent CRISPR/Cas9-mediated inactivation of PERVs, exhibited a significant reduction in viral protein production and the assembly of non-infectious viral particles (Figure 2) (Godehardt et al.,2019). Another study highlighted the successful disruption of PERV pol genes in porcine embryos using electroporation of the Cas9 protein (GEEP) system, which resulted in high-frequency indel mutations and affected embryonic development7. Additionally, the evaluation of CRISPR/Cas9 constructs for targeting porcine genes relevant to xenotransplantation showed efficient disruption with minimal off-target effects, further supporting the potential of this technology in creating PERV-free pigs (Ryczek et al., 2022).

Godehardt et al. (2019) explored the presence and localization of PERV nucleocapsid protein p10 in various cell types using immunohistological techniques. Their study revealed that PERV nucleocapsid p10 was detected in PERV-positive PK15 cells and PERV-B positive 293T/B (33) cells, indicated by prominent green fluorescence, demonstrating active viral protein expression. In contrast, no significant fluorescence was observed in PERV-inactivated PK15 clone 15 cells and PERV-negative 293T cells, suggesting the absence or significant reduction of viral protein expression in these lines. The study used an anti-PERV nucleocapsid p10 antibody to specifically target and visualize the viral protein, validating the antibody's specificity and the robustness of the immunohistological method. These findings highlight the differential expression of PERV proteins in infected versus non-infected cell lines, providing crucial insights into PERV biology and the potential for developing targeted antiviral strategies.

3.3 Potential challenges and limitations in perv eradication

Despite the promising results, several challenges and limitations remain in the eradication of PERVs using CRISPR/Cas9. One major concern is the potential for off-target effects, where the Cas9 enzyme may introduce unintended mutations in the genome, which could have deleterious consequences (Ryczek et al., 2022). Additionally, the efficiency of PERV inactivation can vary depending on the specific gRNAs used, as seen in the differential impact on embryonic development when targeting the PERV pol gene (Hirata et al., 2019). Another challenge is the possibility of incomplete inactivation, where residual viral particles or defective proviruses may still be present, posing a risk of reactivation or recombination with other viral elements (Godehardt et al., 2019). Furthermore, the long-term stability and safety of CRISPR/Cas9-modified pigs need to be thoroughly evaluated before clinical applications in xenotransplantation can be realized. In conclusion, while CRISPR/Cas9 offers a powerful tool for eliminating PERVs and enhancing the biosafety of transplantable pig organs, careful consideration of the associated challenges and ongoing research are essential to fully harness its potential.

4 Enhancing Resistance to Viral and Bacterial Infections

4.1 Genetic modifications to confer resistance to common viral infections (e.g., PRRSV, PCV2)

Genetic modifications have shown significant promise in conferring resistance to common viral infections in pigs, particularly Porcine Reproductive and Respiratory Syndrome Virus (PRRSV). One of the most notable strategies involves the modification of the CD163 gene, which encodes a scavenger receptor critical for PRRSV entry into host cells. Several studies have demonstrated that altering or knocking out specific domains of CD163 can confer resistance to PRRSV. For instance, substituting exon 7 of the porcine CD163 gene with the corresponding exon from human CD163-like 1 (hCD163L1) using CRISPR/Cas9 technology has been shown to inhibit PRRSV replication significantly. This modification resulted in a decreased viral load and improved survival rates in infected pigs (Chen et al., 2019). Similarly, complete knockout of the CD163 gene using CRISPR/Cas9 and somatic cell nuclear transfer (SCNT) technologies has rendered pigs fully resistant to highly pathogenic PRRSV, with no adverse effects on macrophage function (Yang et al., 2018). Another approach involved deleting the scavenger receptor cysteine-rich domain 5 (SRCR5) of CD163, which also conferred complete resistance to PRRSV infection without impairing the biological functions of the protein (Burkard et al., 2018).

4.2 Strategies for enhancing resistance to bacterial pathogens

While the focus on genetic modifications has predominantly been on viral pathogens, there are emerging strategies aimed at enhancing resistance to bacterial infections in pigs. These strategies often involve the manipulation of genes associated with the immune response to bacterial pathogens. For example, the IRF8-miR-10a-SRP14 regulatory pathway has been identified as a critical mechanism by which host cells resist PRRSV infection. This pathway could potentially be targeted to enhance resistance to bacterial pathogens as well (Zheng et al., 2022).

4.3 Case studies and experimental data on pathogen resistance

Several case studies and experimental data highlight the effectiveness of genetic modifications in conferring resistance to pathogens in pigs. In one study, pigs with a modified CD163 gene showed a substantial decrease in viral load and relief from PRRSV-induced symptoms, with a significant number of modified pigs surviving the infection compared to wild-type controls (Figure 3) (Chen et al., 2019). Another study demonstrated that CD163 knockout pigs were completely resistant to highly pathogenic PRRSV, showing no signs of infection or viremia (Yang et al., 2018). Additionally, pigs lacking the SRCR5 domain of CD163 were resistant to multiple subtypes of PRRSV, further validating the effectiveness of this genetic modification (Burkard et al., 2018). Moreover, research on the IRF8-miR-10a-SRP14 pathway has provided insights into the molecular mechanisms of host resistance to PRRSV, suggesting potential new antiviral strategies that could be applied to bacterial infections as well (Zheng et al., 2022). These studies collectively underscore the potential of genetic modifications in enhancing the biosafety of transplantable pig organs by conferring resistance to both viral and bacterial pathogens.

Chen et al. (2019) investigated the resistance of CD163-mutated porcine alveolar macrophages (PAMs) to infection by highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV). The study found that CD163-mutated PAMs exhibited significantly reduced susceptibility to viral infection, evidenced by lower viral titers and RNA expression levels. This resistance was consistently observed across different infection doses and time points. Further protein and immunofluorescence analyses revealed a significant reduction in viral protein expression in these mutated cells. The results suggest that the CD163 mutation restricts the replication and spread of HP-PRRSV in PAMs, thereby inhibiting the efficiency of viral infection. These findings provide new insights and potential molecular targets for developing antiviral strategies against PRRSV infection.

5 Comprehensive Biosafety Strategies

5.1 Combining genetic modifications with other biosafety measures

Combining genetic modifications with other biosafety measures forms a robust framework for enhancing the safety of transplantable pig organs. Genetic modifications, such as the alteration of the CD163 gene to confer resistance to Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), provide a fundamental line of defense against specific pathogens (Wiater et al., 2020). However, the complexity of pathogen dynamics and the risk of new infections necessitate additional biosafety measures. Biosecure facilities play a crucial role by implementing stringent controls that prevent pathogen entry and spread, including controlled access, quarantine protocols, and regular sanitization. Alongside, continuous monitoring through advanced diagnostic tools and routine health checks allows for the early detection and management of infections, thereby complementing the genetic defenses. Integrating vaccination programs with these measures adds another layer of protection, further reducing the risk of infection and enhancing overall biosafety. This comprehensive approach ensures that genetic modifications are supported by a well-rounded system that addresses multiple aspects of pathogen control, ultimately enhancing the safety of pig organs intended for transplantation (Sykes and Sachs, 2019).

5.2 Role of antimicrobial peptides and other genetic enhancements

Antimicrobial peptides (AMPs) and other genetic enhancements represent promising advancements in the effort to eliminate porcine pathogens. AMPs, such as porcine β-defensins, have broad-spectrum antimicrobial properties that can effectively target and neutralize various pathogens, including bacteria, viruses, and fungi. By introducing genes encoding these peptides into the pig genome, researchers can enhance the innate immune response of pigs, providing a built-in defense mechanism against infections. This genetic enhancement is particularly valuable as it offers a proactive approach to pathogen resistance, complementing the passive defense provided by environmental biosafety measures. Other genetic modifications, such as the alteration of immune response genes, further bolster the pig's ability to resist infections. These enhancements ensure that the pigs have an intrinsic capacity to fight off pathogens, reducing the likelihood of disease transmission through transplantable organs. The integration of AMPs and other genetic enhancements into the overall biosafety strategy provides a multi-faceted defense system, significantly improving the resilience of pigs against a wide range of pathogens (Chen et al., 2019).

5.3 Integrative approaches to ensure the safety of transplantable organs

Ensuring the safety of transplantable pig organs requires an integrative approach that combines genetic modifications, biosecurity measures, and advanced pathogen management strategies. A comprehensive risk assessment framework is essential to identify and mitigate potential threats, including the risk of zoonotic disease transmission and immune rejection in recipients. This framework should include continuous pathogen surveillance, risk evaluations, and the development of contingency plans to address potential outbreaks. Collaboration between researchers, veterinarians, and regulatory agencies is vital to establish and maintain high standards of biosafety. This collaboration ensures that genetic modifications and biosafety measures are effectively implemented and regulated across the industry. Additionally, transparency and public engagement are crucial to building trust and acceptance of xenotransplantation. By openly communicating the benefits and safety measures associated with genetically modified pigs, stakeholders can foster a supportive environment for the advancement of this field. This integrative approach, combining scientific innovation with rigorous biosafety practices and public transparency, is essential for ensuring the long-term viability and safety of transplantable pig organs (Ryczek et al., 2022).

6 Ethical and Regulatory Considerations

6.1 Ethical implications of genetically modifying pigs for human benefit

The ethical implications of genetically modifying pigs for human benefit are multifaceted and complex. On one hand, the use of genetically modified pigs in xenotransplantation offers a promising solution to the critical shortage of human organs available for transplantation. This could potentially save countless lives and improve the quality of life for patients suffering from organ failure (Denner, 2018). However, the genetic modification of pigs raises significant ethical concerns. These include the welfare of the animals, the potential for unforeseen consequences in the ecosystem, and the moral considerations of altering the genetic makeup of a species for human benefit. The welfare of genetically modified pigs must be carefully considered, ensuring that the modifications do not cause undue suffering or health issues for the animals1. Additionally, there is a need for a thorough ethical review to balance the potential human benefits against the moral and ecological costs (Cooper et al., 2019).

6.2 Regulatory frameworks governing the use of genetically modified organisms in xenotransplantation

The regulatory frameworks governing the use of genetically modified organisms (GMOs) in xenotransplantation are critical to ensuring the safety and efficacy of these medical procedures. Various countries have established stringent regulations to oversee the development and use of GMOs, including genetically modified pigs, in medical applications. These regulations typically involve rigorous testing and evaluation to assess the potential risks and benefits, including the possibility of zoonotic disease transmission and the long-term effects on both human recipients and the environment (Denner, 2018). For instance, the transmission of porcine cytomegalovirus (PCMV) has been identified as a significant risk factor, necessitating strict regulatory oversight to prevent such occurrences. Regulatory bodies must also ensure that the genetic modifications are stable and do not result in unintended off-target effects, which could compromise the safety of the xenotransplants (Cooper et al., 2019).

6.3 Public perception and societal acceptance of genetically modified pig organs

Public perception and societal acceptance play a crucial role in the successful implementation of xenotransplantation using genetically modified pig organs. Public concerns often revolve around the ethical treatment of animals, the safety of the procedures, and the potential long-term consequences of introducing genetically modified organisms into the human body and the environment. Effective communication and public engagement are essential to address these concerns and build trust in the technology. Transparency in the research and regulatory processes, as well as clear communication of the potential benefits and risks, can help to alleviate public fears and misconceptions. Additionally, societal acceptance may be influenced by cultural and religious beliefs, which must be respectfully considered in the discourse surrounding xenotransplantation (Ryczek et al., 2022). Public education campaigns and stakeholder consultations can play a vital role in fostering a well-informed and supportive public opinion (Lei et al., 2022).

7 Challenges and Future Directions

7.1 Technical challenges in achieving comprehensive pathogen elimination

Achieving comprehensive pathogen elimination in genetically modified pigs for xenotransplantation presents several technical challenges. One significant hurdle is the elimination of porcine endogenous retroviruses (PERVs), which pose a risk of cross-species transmission. Although recent advancements have enabled the inactivation of PERVs using CRISPR-Cas9 technology, ensuring complete and stable elimination remains complex. Additionally, the genetic modification process itself can introduce unintended mutations or off-target effects, complicating the pathogen elimination efforts (Li et al., 2021). Another challenge is the need to disrupt multiple genes responsible for xenoantigens, such as αGal, Neu5Gc, and Sda, which are known to provoke immune responses in humans. The sequential disruption of these genes requires precise and efficient gene-editing techniques to avoid compromising the viability and functionality of the pig organs (Deng, 2022).

7.2 Long-term stability and potential off-target effects of genetic modifications

The long-term stability of genetic modifications in pigs is crucial for the success of xenotransplantation. One concern is the potential for genetic modifications to revert or lose efficacy over time, which could lead to the re-emergence of pathogens or xenoantigens. Ensuring the stable transmission of these modifications across generations is essential, as demonstrated by studies showing normal physiology and fertility in genetically engineered pigs (Kemter et al., 2018). However, the potential off-target effects of gene-editing technologies, such as CRISPR-Cas9, remain a significant concern. These off-target effects can lead to unintended genetic changes that may affect the health and safety of the modified pigs and the recipients of their organs (Li et al., 2021). Continuous monitoring and refinement of gene-editing techniques are necessary to minimize these risks and ensure the long-term success of xenotransplantation.

7.3 Future research directions and potential breakthroughs in biosafety enhancement

Future research in the field of xenotransplantation should focus on several key areas to enhance biosafety. One promising direction is the development of more sophisticated gene-editing tools that offer higher precision and fewer off-target effects, thereby improving the safety and efficacy of genetic modifications. Additionally, research should explore the combination of genetic modifications with advanced immunosuppressive therapies to further reduce the risk of immune rejection and improve graft survival (Sykes and Sachs, 2019). Another potential breakthrough lies in the comprehensive characterization and elimination of all potential pathogens, including those not yet identified, through advanced genomic and proteomic techniques49. Finally, the establishment of robust in vitro and in vivo models to evaluate the safety and efficacy of genetically modified pig organs before clinical trials will be crucial in accelerating the translation of xenotransplantation into clinical practice (Lei et al., 2022). By addressing these challenges and pursuing these research directions, the field of xenotransplantation can move closer to providing a reliable and safe solution to the organ shortage crisis.

8 Concluding Remarks

The research on genetic modifications in pigs for xenotransplantation has shown significant progress in addressing the immunological barriers and potential zoonotic risks associated with the procedure. The use of CRISPR/Cas9 technology to modify specific porcine genes such as GGTA1, CMAH, β4GalNT2, vWF, and ASGR1 has demonstrated efficiency in preventing xenograft rejection by human recipients1. Additionally, the off-target effects of these genetic modifications have been assessed, ensuring the precision and safety of the genetic alterations. Another critical finding is the impact of porcine cytomegalovirus (PCMV) on the survival time of pig xenotransplants. PCMV has been identified as a significant factor in reducing transplant survival by disrupting the coagulation system and suppressing the immune system in non-human primates. This highlights the necessity of eliminating PCMV from donor pigs to enhance the success of xenotransplantation.

The advancements in genetic modifications using CRISPR/Cas9 technology pave the way for more successful xenotransplantation by reducing the risk of immunological rejection. This technology allows for precise and efficient editing of the porcine genome, which is crucial for making pig organs more compatible with human recipients. Furthermore, the identification of PCMV as a critical factor in transplant survival underscores the importance of rigorous screening and elimination of zoonotic pathogens from donor pigs. Ensuring the absence of such pathogens will significantly improve the biosafety of transplantable pig organs and increase the likelihood of successful clinical applications. These findings collectively suggest that with continued advancements in genetic engineering and pathogen control, xenotransplantation could become a viable solution to the organ shortage crisis.

To fully realize the potential of xenotransplantation, it is imperative to continue research in genetic modifications and pathogen elimination. Researchers should focus on refining CRISPR/Cas9 techniques to further minimize off-target effects and enhance the precision of genetic edits. Additionally, there is a need for comprehensive studies on the transmission mechanisms and impacts of zoonotic pathogens like PCMV to develop effective strategies for their elimination. Interdisciplinary collaboration among geneticists, immunologists, virologists, and transplant surgeons is essential to address the multifaceted challenges of xenotransplantation. By working together, these experts can develop innovative solutions that ensure the safety and efficacy of transplantable pig organs, ultimately improving patient outcomes and addressing the global organ shortage.

Acknowledgments

Authors extends our sincere thanks to two anonymous peer reviewers for their invaluable feedback on the initial draft of this manuscript.

Conflict of Interest Disclosure

Authors affirm that this research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest.

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