Stem cell therapy for inherited retinal diseases: Trends and insights from 2000 to 2024

Abstract

Stem cell therapy has emerged as a promising strategy for inherited retinal diseases (IRDs), yet its global research trajectory has not been systematically mapped. This study analyzes publication trends, leading contributors, and thematic evolution of IRD stem cell therapy research from 2000 to 2024. Publications were retrieved from the Web of Science Core Collection and analyzed with CiteSpace and VOSviewer. We identified 1060 articles with a steady rise in annual output. The United States and China were the most prolific countries; University College London and the University of Iowa were major institutions; and key outlets included Stem Cell Research & Therapy, Investigative Ophthalmology & Visual Science, and Cell Transplantation. Keyword and co-citation analyses reveal a clear trajectory: early emphasis on stem cell–derived retinal pigment epithelium transplantation for photoreceptor rescue, subsequent expansion to photoreceptor precursor and retinal organoid replacement, and recent movement toward early clinical translation. Persisting challenges include long-term graft survival, functional integration, and immune compatibility. Overall, this bibliometric roadmap clarifies how the field is transitioning from foundational studies to translational application and highlights priorities for interdisciplinary collaboration to accelerate clinical advancement.

Graphical Abstract

Keywords

stem cell therapy inherited retinal diseases bibliometric analysis induced pluripotent stem cells human embryonic stem cells retinitis pigmentosa Stargardt disease

Introduction

Inherited retinal diseases (IRDs) comprise a heterogeneous group of inherited ocular disorders, including retinitis pigmentosa (RP), Stargardt disease, and other forms of retinal degeneration. These conditions are characterized by dysfunction and loss of photoreceptors or retinal pigment epithelium (RPE), ultimately leading to vision loss¹. Approximately 2.7 billion individuals worldwide carry mutations associated with IRDs; the incidence is roughly 1 per 1380 persons, affecting an estimated 5.5 million people globally². Among IRDs, RP is one of the most prevalent, with a global prevalence of ~1 in 4000; it manifests as progressive nyctalopia, visual-field constriction, and eventual central vision loss due to degeneration of rod and cone photoreceptors^3,4. Stargardt disease is the most common macular dystrophy in adolescents; earlier onset correlates with greater severity and substantial reductions in quality of life owing to central vision loss⁵. IRDs arise predominantly from inherited pathogenic variants and exhibit extensive genetic and phenotypic heterogeneity, producing diverse symptoms and clinical trajectories that complicate diagnosis and treatment^6,7.

In recent years, stem cell–based therapy has emerged as a promising strategy for patients with IRDs. Pluripotent stem cells—particularly human induced pluripotent stem cells (iPSCs) and human embryonic stem cells (hESCs)—possess self-renewal and multilineage differentiation capacity, enabling generation of retinal cell types required to repair or replace damaged photoreceptors or RPE⁸. From early hESC studies to the current focus on iPSCs, pluripotent cells have introduced new therapeutic concepts for RP. Transplantation of stem cell–derived RPE has achieved partial restoration of visual function^9,10. Multiple animal studies and early clinical investigations have further demonstrated significant functional benefit, underscoring the therapeutic promise of stem cell interventions^11–13.

Importantly, distinct transplantation strategies pursue different therapeutic objectives. Transplantation of stem cell–derived RPE primarily seeks to support or rescue surviving photoreceptors by replacing dysfunctional RPE^14,15, whereas transplantation of stem cell–derived retinal organoids or photoreceptors is intended to replace photoreceptors lost to degeneration^16–18. Clarifying this distinction is essential for interpreting the scope and goals of stem cell therapy in IRDs.

Despite substantial progress, key challenges remain for clinical implementation, including rigorous validation of safety, efficacy, and long-term outcomes^18,19. The rapid expansion of stem cell research in IRDs has led to a marked increase in publications worldwide. Bibliometric analysis²⁰ can delineate developmental trajectories, quantify research impact, map collaboration networks, and identify future directions—insights that are valuable for researchers and can facilitate clinical translation. Despite recent progress, a comprehensive assessment of IRD stem cell therapy remains lacking. A recent bibliometric study on retinal organoids provided insights into this subfield²¹, but no systematic evaluation has addressed IRD stem cell therapy as a whole, underscoring the novelty of our study.

Prior studies have largely centered on individual experiments or narrative reviews, without providing a holistic view of global trends, influential publications, leading authors and institutions, or international collaboration patterns. Moreover, the evolution of research hotspots and future directions has not been comprehensively characterized. To address these gaps, we conduct a systematic bibliometric analysis to inform researchers and catalyze further progress in the field. The primary research questions are as follows:

Research Question 1: What are the publication trends in stem cell therapy research for IRD?

Research Question 2: Which countries/regions, institutions, journals, lead authors, and publications have the most significant influence in this field?

Research Question 3: What are the global collaboration patterns among authors, institutions, and countries/regions?

Research Question 4: What are the key research themes and their evolution over time?

Methods

The Web of Science Core Collection (WoSCC) was selected as the primary data source because it provides broad historical coverage and superior citation-tracking compared with PubMed and Scopus. Its precise citation linkage enables comprehensive retrieval of citing/cited records. We limited the search to WoSCC and extracted records published between January 1, 2000 and December 31, 2024. The full search strategy is shown in Fig. 1. We included English-language research articles and review articles only.

Figure 1.

Screening chart of included studies.

Titles, abstracts, and full texts were screened against predefined inclusion and exclusion criteria, yielding 1060 eligible records. Extracted fields included publication year, country/region, institution, author, journal, keywords, and citation counts. Two reviewers independently screened all records after a pilot calibration on a subset to standardize decisions. Discrepancies were resolved by discussion, with arbitration by a third reviewer when necessary. This multi-step process was designed to minimize bias, enhance transparency, and improve reproducibility. We used VOSviewer (https://www.vosviewer.com) to construct and visualize co-authorship, co-occurrence, and keyword-density maps and to depict collaboration structures and research hotspots²². CiteSpace (http://cluster.cis.drexel.edu/~cchen/citespace/) was used to identify high-impact literature (co-citation networks), detect citation bursts, and profile emerging trends²³. Publication-trend charts were generated in Microsoft Excel. Visualizations from VOSviewer and CiteSpace were jointly interpreted to characterize research patterns, influential scholars and outlets, and topical evolution. Multiple cross-checks were performed to ensure data accuracy.

Results

Growth trend in publications (2000–2024)

As shown in Fig. 2, annual publications from 2000 to 2024 remained modest before 2006 and then rose steadily from 2007, reflecting growing interest in regenerative ophthalmology. A pronounced upswing occurred after 2012, with output expanding from 22 papers in 2012 to 99 in 2024—roughly a four- to five-fold increase over the period. This expansion coincides with seminal advances, including iPSC technology, three-dimensional retinal organoids, and the initiation of early clinical studies. A further inflection between 2018 and 2020 may indicate intensifying interdisciplinary collaboration and a stronger translational focus. Despite minor year-to-year variability between 2020 and 2023, overall productivity remained high, culminating in a peak in 2024. Collectively, these trends suggest a maturing research landscape and a growing commitment to translating laboratory advances into clinically meaningful outcomes for IRDs.

Figure 2.

Growth trend in publications (2000–2024).

Overview of national publications

As shown in Fig. 3a, the United States occupies a central position in the international collaboration network, with robust links to China, England, and Germany—reflecting leadership in both publication output and cross-border partnerships. Based on WoSCC (2000–2024), the Top 10 countries by publication count are: the United States (431), China (179), England (128), Germany (68), Japan (66), France (62), Spain (52), Australia (51), Italy (46), and the Netherlands (38). These numbers highlight the dominance of countries with high economic development and strong biomedical infrastructures. Germany, Japan, France, and others contribute steadily, reflecting the global nature of stem cell research in IRDs. Overall, leading countries not only drive output but also foster cross-border collaboration, which is essential for advancing complex translational research.

Figure 3.

Integrated landscape of countries, institutions, authors, and journals in stem cell therapy for IRDs. (a) Country collaboration network: each node represents a country/region, with node size proportional to the number of publications; the number of connecting lines reflects the intensity of collaboration; node color indicates clusters of countries/regions with closer cooperation. (b) Institutional collaboration network: each node represents an institution, with node size proportional to publication output; the number of connecting lines reflects the intensity of inter-institutional collaboration; node color indicates clusters of institutions with stronger partnerships. (c) Author density map: color intensity reflects the number of publications and collaboration frequency, with darker colors indicating higher productivity and stronger collaborative activity. (d) Journal density map: color intensity reflects the number of articles published in each journal, with darker colors indicating higher output. All data were obtained from the Web of Science Core Collection (2000–2024) and visualized using VOSviewer and CiteSpace.

Map of institutional cooperation

Fig. 3b presents a dense interinstitutional collaboration network with prominent hubs such as University College London (UCL), the UCL Institute of Ophthalmology, Moorfields Eye Hospital, the University of Iowa, Columbia University, and the University of Western Australia. Publication counts for the top institutions are: UCL (47), University of Iowa (36), UCL Institute of Ophthalmology (35), Columbia University (29), University of Western Australia (26), Moorfields Eye Hospital (24), Harvard University (21), The Johns Hopkins University (20), Harvard Medical School (20), and Lions Eye Institute (19). Although the UCL Institute of Ophthalmology is part of UCL, it appears as a separate entity in WoSCC owing to its distinct research emphasis (ophthalmic stem cell therapy at the Institute versus broader regenerative medicine across other UCL departments). This separation explains the presence of both entities in the network and highlights the breadth of UCL-affiliated activity.

Author analysis

As shown in Fig. 3c, clusters of authors such as Budd A. Tucker, Robert F. Mullins, and Fred K. Chen form strong co-authorship networks, underscoring their central positions in the field. In terms of productivity, Tucker leads with 29 publications, followed by Mullins (27) and Stone (27). Other highly active contributors include Fred K. Chen (18), Samuel McLenachan (17), Dan Zhang (16), Shang-Chih Chen (15), Luke A. Wiley (15), Jennifer A. Thompson (13), and John N. De Roach (12).

Because WoS data do not distinguish between first authors and senior (corresponding) authors, names shown in the network represent overall author contributions. Both roles are integral to scientific work: first authors typically perform the primary experimental and analytical tasks, whereas senior authors provide conceptual guidance, resources, and supervision.

It is noteworthy that, although several of the most prolific authors—Tucker, Mullins, and Stone—are affiliated with the University of Iowa, the institution’s total output remains lower than that of UCL. This apparent discrepancy reflects frequent co-authorship among Iowa researchers, which increases individual author counts without proportionally raising the institutional total. By contrast, UCL’s publications originate from multiple relatively independent groups, yielding a higher cumulative output. This comparison illustrates how author-level and institution-level bibliometric perspectives may diverge.

Journal analysis

As shown in Fig. 3d, the most active journals are Stem Cell Research (63 articles), Investigative Ophthalmology & Visual Science (45), and the International Journal of Molecular Sciences (38), reflecting a strong focus on stem cell biology, ophthalmology, and molecular research. Additional outlets—including Experimental Eye Research, Stem Cell Reports, and Progress in Retinal and Eye Research—each published roughly 20–30 papers, while most journals contributed fewer than 20 articles. The density map shows publication activity concentrated in a limited number of specialized journals, with warmer regions marking higher outputs. Citation patterns further indicate that citing journals cluster within life sciences, ophthalmology, clinical medicine, and molecular biology, while cited journals extend into broader domains (e.g., computer science, environmental sciences, nutrition). This points to increasing interdisciplinarity, with computational methods applied to retinal modeling and image analysis, and environmental/nutritional insights informing stem cell microenvironments. Overall, the journal analysis highlights both disciplinary concentration and cross-field integration that together shape advances in IRD stem cell therapy research.

Graph of author and reference network analysis with citation highlighting

Among the 497 co-cited references, Schwartz SD (2012) occupies the largest node in the co-citation network. The most frequently cited article—Schwartz SD, The Lancet (2015)—has accrued 131 citations²⁴. The reference with the strongest citation-burst intensity is Schwartz SD (2012), “Embryonic stem cell trials for macular degeneration: a preliminary report”²⁵, which substantially influenced subsequent clinical use of stem cell–based therapies. Other highly influential studies, such as those by Capowski (2016) and Meyer (2011), advanced retinal cell differentiation protocols and disease modeling, respectively. Their presence in both the co-citation map and burst analysis indicates that foundational work spanning basic biology and early clinical translation continues to shape current research priorities. Preclinical IRD research has likewise been anchored in well-characterized degeneration models—most notably the rd1 (Pde6b) mouse and the RCS (Mertk) rat—which provide robust in vivo platforms to test photoreceptor rescue and replacement strategies^26,27.

Complementing these models, transplantation of stem cell–derived retinal tissues has progressed from preclinical organoid-sheet engraftment in degenerative mice to early human studies: ESC/iPSC-derived 3D retinal sheets demonstrated survival and maturation with host–graft synaptic contacts in mouse models, and 2-year safety with stable graft survival has been reported in patients with RP^17,18.

Overall, these findings underscore the pivotal role of early clinical trials and protocol-defining experimental studies in steering the trajectory of stem cell therapy for IRDs, thereby bridging the gap between laboratory models and therapeutic applications (Fig. 4)

Figure 4.

Author and reference network analysis with citation highlighting. (a) Reference co-citation network: node size reflects citation frequency; larger nodes indicate higher influence. (b) Top 20 references with the strongest citation bursts: red bars denote periods of intensive citation activity. Together, the panels depict both the core literature shaping the field and the temporal dynamics of its impact.

Keyword analysis of trending research topic

As shown in Fig. 5a, high-frequency keywords such as “retinitis pigmentosa,” “macular degeneration,” and “stem cells” indicate sustained emphasis on retinal degenerative diseases in the context of stem cell therapy. The dense interlinking of terms reflects an integrated research landscape in which gene therapy, cell transplantation, and retinal pathology frequently intersect.

Figure 5.

Keyword analysis. (a) Keyword co-occurrence network. (b) Keyword clustering map (color regions denote distinct research themes). (c) Top 27 burst keywords (red bars indicate years of intensive citation activity).

Fig. 5b reveals eight major keyword clusters, with prominent themes including pluripotent stem cells, age-related macular degeneration, and progenitor cells. These clusters represent core research directions and suggest that both cellular reprogramming and gene-based interventions are central to therapeutic development for IRDs.

Fig. 5c presents the top 27 keywords with the strongest citation bursts (2000–2024). Notably, “in vitro,” “neural retina,” and “embryonic stem cells” show the highest historical intensities, marking earlier hotspots. “Progenitor cells” exhibits the longest sustained interest (2002–2014), whereas “retinal organoids” represents the most recent and ongoing burst (2020–2024), highlighting a shift toward 3D tissue modeling. Consistent with these bursts, topic-level signals delineate a phased trajectory: early RPE-based interventions aimed at supporting or rescuing photoreceptor function^14,15; subsequent emphasis on photoreceptor precursors and retinal-organoid/retinal-sheet transplantation, reflecting a move toward cellular replacement^16,17; and most recently, first-in-human iPSC-derived retinal-organoid grafts demonstrating 2-year survival and safety, marking the onset of early clinical translation¹⁸. This trajectory is exemplified by photoreceptor-precursor transplantation in degenerative mice and organoid-sheet transplantation extending into early human studies^17,18. Together, these observations chart a progression from supportive to replacement strategies and now to translational exploration.

This temporal evolution—from basic cellular studies to clinically relevant models—suggests that retinal organoids will continue to play a leading role in disease modeling, drug testing, and cell-replacement paradigms. Collectively, the frequency, clustering, and burst analyses reveal a field in transition toward precision modeling and personalized regenerative strategies, potentially accelerating clinical application in IRDs.

Significant research directions are captured by keyword clusters—including progenitor cells, gene therapy, stem cells, inherited retinal disease, and retinal degeneration—which underscore a growing emphasis on integrating cellular and genetic approaches to restore retinal function. The convergence of stem cell therapy with gene editing reflects a shift toward multimodal strategies that address both genetic defects and cellular loss. The frequent co-occurrence of these terms indicates movement beyond single-modality interventions toward mechanism-based, combinatorial therapies. The use of gene-editing tools and animal models further underscores efforts to validate efficacy across molecular, cellular, and functional levels, charting a promising path to personalized regenerative treatments.

Fig. 6a shows the keyword time-zone map, evidencing a clear temporal evolution of priorities. Early studies (2000–2010) emphasized retinal degeneration, disease pathology, and in vitro models, reflecting foundational mechanistic exploration. From 2010 to 2020, attention shifted toward differentiation, transplantation, and gene therapy, signaling the rise of translational strategies. In the most recent period (2020–2024), topics such as retinal organoids, photoreceptor transplantation, and Stargardt disease have emerged, marking a turn toward clinical application, 3D tissue engineering, and disease-specific interventions.

Figure 6.

Time diagram of keyword evolution. The figure demonstrates the keyword evolution in the study of stem cell therapy for IRD. (a) Keyword time-zone map. The size of the nodes represents the frequency of the keywords, and the brighter yellow color represents the heat of the study. (b) Keyword clustering study evolution timeline graph. Each line represents the evolution of a keyword cluster over time, and the node size indicates the frequency of occurrence of the keyword in a given time period.

Fig. 6b further traces cluster-level evolution. Research on pluripotent stem cells has progressed from degeneration/mutation studies to differentiation, transplantation, and early clinical application in age-related macular degeneration—illustrating the transition from bench research to applied therapeutics. By contrast, progenitor-cell work, while active earlier, shows more limited translational momentum. Importantly, photoreceptor-focused studies, once centered on degeneration and gene expression, are increasingly linked to transplantation and functional integration, underscoring their clinical promise.

Taken together, these patterns depict a field in transition—from foundational biology to translational and clinical innovation. The sustained focus on pluripotent stem cells, coupled with the recent rise of retinal organoids and photoreceptor transplantation, signals a strategic pivot toward personalized, tissue-specific therapies. These advances not only deepen the understanding of disease mechanisms but also establish scalable platforms for drug testing and cell replacement, highlighting steady movement toward clinical validation and precision regenerative strategies for IRDs.

In summary, the evolution of research hotspots in stem cell therapy for IRDs can be delineated into three phases: an early phase (2000–2010) centered on retinal degeneration and disease mechanisms; a transitional phase (2010–2020) emphasizing differentiation, transplantation, and gene therapy; and a recent phase (2020–2024) highlighting retinal organoids, photoreceptor replacement, and clinical translation. This trajectory demonstrates a shift from foundational biological studies to translational strategies and, most recently, to early clinical applications, underscoring the growing potential of stem cell–based interventions for IRDs.

Discussion

Over the past two decades, research in this field has grown substantially—particularly after 2010—driven by breakthroughs in iPSC and organoid technologies^28,29. Between 2000 and 2010, research hotspots centered on foundational topics such as RP and the regenerative potential of retinal progenitor cells. Since 2010, the focus has shifted toward pluripotent stem cells, gene therapy, and retinal organoids^30,31. Continued multidisciplinary integration and the deepening of clinical applications are expected to propel future progress³². Collectively, these findings illuminate the overall research landscape and the key factors shaping the field’s future trajectory. Stem cell therapy has traversed several developmental phases, advancing from early explorations to clinical application and establishing itself as a major research focus³³.

The evolution of research hotspots in stem cell therapy for IRD is influenced by multiple factors. Between 2000 and 2010, early work primarily investigated the pathological mechanisms of IRDs such as RP, as well as the regenerative capacity of retinal progenitor cells. During this period, technological constraints—such as the lack of stable stem cell sources and reliable human-derived models—limited the scope of investigation. Consequently, most studies emphasized basic research, including small-animal experiments, gene-mutation identification, and delineation of retinal cell–differentiation pathways^34,35.

The widespread adoption of animal models became crucial for validating these mechanisms³⁶, as studies demonstrated that transplanted precursor cells could survive, differentiate into specific retinal cell types, and form functional synaptic connections, partially restoring visual function^16,37,38. While this body of work established a foundation for understanding disease mechanisms, clinical translation remained limited.

Since 2010, the advent of iPSC technology and 3D retinal-organoid systems has marked a transformative phase. These innovations enabled disease modeling with patient-derived cells, providing physiologically relevant platforms for mechanistic investigation and therapeutic assessment. As a result, the field has gradually shifted from a traditional “mechanism-oriented” approach to a more “application-oriented” trajectory, with increasing attention to clinical strategies such as personalized therapy, gene editing, and cell replacement.

Researchers began evaluating the potential of transplanting differentiated retinal cells to restore vision³⁹, yielding encouraging outcomes in animal models⁴⁰. The emergence of clinical trials represents a significant transition from laboratory-based research to the practical application of stem cell therapy for IRD. For instance, a significant clinical trial involved transplanting iPSC-derived RPE sheets into a 77-year-old woman⁴¹. Although no adverse effects were observed, the trial was later suspended, and concerns over genomic instability highlighted the need for further safety evaluations⁴².

Public-health demands, population aging, and the high prevalence of retinal disease are driving the pursuit of innovative therapeutic approaches. Research increasingly focuses on genetic correction of patient-specific iPSCs and the generation of healthy retinal cells, aiming to improve graft success and durability^43,44. In recent years, several stem cell–based therapies have entered clinical trials, with safety and long-term efficacy becoming central concerns^45,46. Literature reviews highlight persistent worries about the safety of stem cell therapies, especially concerning the use of hESCs and iPSCs. Avoiding ectopic proliferation and tumor formation remains a critical challenge in clinical applications. In addition, ensuring long-term survival of transplanted cells and their functional integration with the host visual system remains an urgent challenge—not only for RPE transplantation but also for photoreceptor and retinal-organoid transplantation^18,47–49. Future research is likely to focus on optimizing stem cell functionality and safety through gene editing and molecular modulation to enhance therapeutic outcomes and mitigate risks. Recent studies have shown that mesenchymal stem cell–based approaches may provide neuroprotective and immunomodulatory support for degenerating retinas⁵⁰, and that mesenchymal stem cell–derived extracellular vesicles (MSC-EVs) can further attenuate immune-mediated rejection while promoting retinal cell survival⁵¹. These findings broaden the translational framework, suggesting that combining photoreceptor or organoid transplantation with adjunctive MSC-based strategies may improve long-term graft survival and functional integration.

Although stem cell–based therapies show considerable clinical potential, their ethical dimensions remain complex and far-reaching. The use of hESCs, in particular, continues to spark controversy due to concerns regarding the moral status and right to life of embryos. Notably, the National Institutes of Health (NIH) has established strict ethical criteria for hESC lines to be added to the NIH registry (https://stemcells.nih.gov/research-policy/guidelines-for-human-stem-cell-research). In some regions, such work is tightly regulated or prohibited, and in others, it remains politically charged within broader debates on human rights and medical ethics. Furthermore, the advent of iPSC technology—which involves reprogramming adult cells into an embryonic-like state—while circumventing some ethical dilemmas associated with embryonic stem cells, introduces new ethical challenges. These include concerns related to informed consent, privacy protection, and the opaque use of biological materials. Existing ethical review mechanisms remain inadequate in addressing these issues, particularly in the context of transnational research and clinical translation. To ensure the sustainable development of stem cell technologies, future research must integrate ethical governance into the management framework across the entire research cycle. This includes strengthening informed consent procedures, enhancing transparency, and promoting the harmonization of international ethical standards to support the safe, regulated, and responsible advancement of the field.^52,53

Breakthroughs in basic and translational science have positioned the field on the threshold of human clinical studies with the potential to restore vision. Numerous early-phase trials are underway worldwide, and their outcomes may be transformative. Multidisciplinary collaboration is crucial for translating basic discoveries into clinical application, especially for complex genetic disorders⁵⁴. This cross-disciplinary approach both deepens mechanistic understanding and provides a more reliable framework and technical basis for clinical trials.

Since 2020, organoid technology has become a major research focus, leveraging 3D tissue engineering to model retinal development and offering new platforms for disease study⁵⁵. This trend is driven not only by advances in technological platforms and the urgent need for effective treatments but also by synergy among stem cell biology, engineering, and clinical medicine^56,57. Bibliometric analyses show that the United States, the United Kingdom, and China dominate this area, with leading institutions including Harvard, UCL, and the University of Iowa. Close transnational collaboration has accelerated the development of emerging technologies and fostered global integration of research capacity. Network analyses of co-cited literature indicate increasing reliance on gene editing, organoids, and in vivo/in vitro models to more accurately recapitulate disease processes and evaluate therapeutic effects. These advances allow scientists to replicate the retina’s complex structure and function in the laboratory, with photoreceptor transplantation proposed as a promising strategy for replacing lost retinal cells^58,59. However, the relative weakness in fundamental mechanistic research, the challenge of standardizing model systems, and the simultaneous presence of clinical feasibility and ethical risks highlight the need for caution against the “hollowing out of science” caused by overly rapid translation. Future research should strive to balance innovation with standardization. While advancing therapeutic development, it is equally important to reinforce fundamental investigations into key issues such as cell integration, functional recovery, and long-term safety. This balanced approach is essential to establish a stem cell therapy pathway that is scientifically rigorous, ethically sound, and clinically viable.

In summary, stem cell therapy for IRD has expanded rapidly, as evidenced by bibliometric analyses of literature from 2000 to 2024. With advances in pluripotent stem cells, organoid technology, and gene editing, the field is steadily transitioning from basic research to clinical application. The prospects for future development are substantial—particularly in personalized and precision medicine—offering new hope for patients with IRD. As innovative technologies continue to evolve, stem cell therapy is poised to usher in a new era of treatment for IRD, bringing renewed optimism to affected individuals.

Limitations of the study

This study has some limitations. First, the search was confined to the WOS database, excluding resources like Google Scholar and PubMed, which may have resulted in the omission of relevant publications. Second, only English-language literature was included, introducing potential language bias. Third, this study primarily focused on bibliometric indicators and did not extensively examine the practical application or efficacy of stem cell therapy, thereby limiting its clinical relevance. In addition, the time span of the analysis may affect the timeliness of the findings, while research conclusions are influenced by disciplinary biases, institutional affiliations, and national preferences, making it challenging to fully capture the global research landscape. There is a potential limitation that some studies using highly specific IRD terminology may not have been fully captured despite the broad scope of our search strategy. It is recognized that citation-based bibliometric methods may underrepresent the impact of smaller studies or those reporting negative results; this limitation was taken into account when interpreting the findings. Future studies can enhance comprehensiveness and accuracy by integrating data from multiple databases and employing more advanced analytical methods.

Conclusion

This study is the first to apply bibliometric and visualization analyses to provide a systematic overview of global research on stem cell therapy for IRDs (2000–2024). We mapped contributions by countries, institutions, authors, and journals and summarized evolving hotspots. The findings reveal a thematic progression from RPE-based photoreceptor rescue to photoreceptor/organoid replacement and, most recently, early clinical translation, supported by representative landmark studies. Despite these advances, key challenges remain in ensuring long-term graft survival, functional integration, and immune compatibility. Overall, our results offer an evidence-based roadmap for understanding the field’s development and provide valuable guidance for future interdisciplinary collaboration and translational efforts.

Footnotes

ORCID iDs

Jinyi Long

Ziyang Xu

Ping Hu

Yuhong Ye

Da Long

Ethical Considerations

This article does not involve any studies with human participants or animals. Therefore, ethics committee approval and informed consent were not required.

Author Contributions

JL: Conceptualization, Writing—original draft, Visualization, Writing—review & editing. JL, ZX, PH, YY: Writing—review & editing, Data curation, Formal analysis, Methodology. DL: Conceptualization, Supervision, Funding acquisition, Project administration. All authors had full access to all data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. All authors have read and approved the final version of the manuscript.

Funding

The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was funded by the National Natural Science Foundation of China (grant no. 81973910) (China).

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Data Availability Statements

Original data were obtained from the WoSCC database. The dataset of the present study is available on request from the corresponding author, Da Long.

Statement of Human and Animal Rights

This article does not contain any studies with human or animal subjects.

Statement of Informed Consent

There are no human subjects in this article, hence informed consent is not applicable.

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