ObjectiveTo investigate the current status of research in gene therapy for retinitis pigmentosa (RP) from 2005 to 2024. MethodsThe literature related to gene therapy for RP included in the Web of Science Core Collection dataset from January 1, 2005 to September 15, 2024 was retrieved and screened. The bibliometrix package of R software was used to analyze the annual trend of the number of publications, citation frequency, distribution of countries/regions of the literature, and distribution of journals containing the articles. CiteSpace software was used to perform keyword clustering analysis and the keywords bursts analysis. ResultsA total of 209 articles were included. There was an overall fluctuating upward trend of annual publications from 2005 to 2024, with the highest number of publications in 2023 at 26 (12.4%, 26/209), and the lowest number of publications in 2006 at 2 (0.9%, 2/209). There was an overall increasing trend in the frequency of citations to relevant literature. Corresponding authors from the United States had the highest total number of publications with 98 (46.9%, 98/209). Among authors, Hauswirth from the University of Florida, USA, had the most with 25 (12.0%, 25/209). Among institutions, Columbia University, USA, had the most with 55 (26.3%, 55/209). Among journals, Mol Ther had the most with 25 (12.0%, 25/209), and it had the highest 2023 impact factor of 12.1. Keyword clustering analysis yielded eight valid clusters, namely #0 P23H, #1 AAV, #2 PDE6B, #3 CRB1, #4 RPGR, #5 antisense oligonucleotide, #6 NR2E3, and #7 NRL, which intersected with each other with good continuity. The keywords bursts analysis showed that the keyword with the longest emergence time was RNAi, followed by PDE and PDE6. USH2A, CRB1, CRISPR Cas9, base editing, and ORF15 were keywords that emerged in recent years and were continuously studied. ConclusionsRP gene therapy research literature has shown an increasing trend from 2005 to 2024, with the highest number of publications from research organizations and scholars in the United States. Currently, studies focus on RHO, PDE6B, CRB1, RPGR, NR2E3, and NRL gene. In recent years, there has been a gradual increase in studies on USH2A, CRB1 genes, and the RPGR ORF15 region. CRISPR Cas9 and base editing gene therapy strategies are being developed.
Retinitis pigmentosa (RP) is a genetic disorder of photoreceptor cell apoptosis and retinal pigment epithelium (RPE) cell atrophy caused by gene mutation. The clinical manifestations are night blindness, peripheral visual field loss and progressive vision loss. RPE cell apoptosis plays an important role in the progression of RP, and exogenous implantation of RPE cells as an alternative therapy has shown certain efficacy in animal experiments and clinical trials. With the diversification of cell sources, the update of surgical techniques and the continuous emergence of biological materials, more possibilities and hopes are provided for cell therapy. To further promote the development of this field in the future, it is still necessary to strengthen the cooperation between medicine, bioengineering and other disciplines in the future to jointly promote the innovation and development of therapeutic methods. It is believed that RPE cell transplantation therapy will show a brighter prospect in the future
Retinitis pigmentosa (RP) is an inherited retinal disease characterized by degeneration of retinal pigment epithelial cells. Precision medicine is a new medical model that applies modern genetic technology, combining living environment, clinical data of patients, molecular imaging technology and bio-information technology to achieve accurate diagnosis and treatment, and establish personalized disease prevention and treatment model. At present, precise diagnosis of RP is mainly based on next-generation sequencing technology and preimplantation genetic diagnosis, while precise therapy is mainly reflected in gene therapy, stem cell transplantation and gene-stem cell therapy. Although the current research on precision medicine for RP has achieved remarkable results, there are still many problems in the application process that is needed close attention. For instance, the current gene therapy cannot completely treat dominant or advanced genetic diseases, the safety of gene editing technology has not been solved, the cells after stem cell transplantation cannot be effectively integrated with the host, gene sequencing has not been fully popularized, and the big data information platform is imperfect. It is believed that with the in-depth research of gene sequencing technology, regenerative medicine and the successful development of clinical trials, the precision medicine for RP will be gradually improved and is expected to be applied to improve the vision of patients with RP in the future.
Objective To analyze the pathogenic gene and clinical phenotypes of a family affected with rare sector retinitis pigmentosa (sector RP). Methods A retrospective clinical study. A patient with sector RP diagnosed in Renmin Hospital of Wuhan University and his parents were included in the study. Detailed medical history was collected; best corrected visual acuity (BCVA), fundus color photography, autofluorescence (AF), visual field, optical coherence tomography (OCT), electroretinogram, fluorescein fundus angiography (FFA), indocyanine green angiography (ICGA) examination were performed. The peripheral venous blood of the patient and his parents were collected, and DNA was extracted. A whole exon sequencing was used for the proband. The mutations were verified by targeted Sanger sequencing and quantitative polymerase chain reaction. Bioinformatics analysis and cosegregation analysis were performed. ResultsThe proband, a 17-year-old male, had presented with gradually decreased vision in the past 2 years with BCVA of 0.4 in both eyes. Retinal vessels attenuation and macular dystrophy without obvious pigmentation on the fundus were observed. AF showed, in bilateral eyes, a symmetrical hypo-autofluorescent region only in the inferonasal quadrant and “petal-like” hyper-AF macula. The visual field examination showed defects in the superotemporal quadrant corresponding to the affected retina. OCT showed loss of the photoreceptor layer except for the foveal region. Electroretinogram examination presented reduced scotopic wave peaks and extinct photopic response. FFA and ICGA showed the atrophy retinal pigment epithelium around the optic disk and in the inferior retina. The clinical phenotypes of the parents were normal. The whole exon sequencing identified one mutation in SPATA7 gene, c.1112T>C (p.Ile371Thr) in exon10 and a copy number variation in trans. The missense mutation resulted in the change of isoleucine to threonine at amino acid 371 in the encoded SPATA7 protein, and the mother carried this heterozygous mutation c.1112T>C. According to the guidelines of the American College of Medical Genetics and Genomics (ACMG) criteria and guidelines for classification of genetic variants, the missense mutation was classified as the uncertain significance. The CNV, originating from his father, contributed to the loss of exon10 and was confirmed as the likely pathogenic variant. ConclusionsThe macula can be involved in sector RP, leading to the macular dystrophy. The missense variant in SPATA7 gene, c.1112T>C (p.Ile371Thr), might be a pathogenic mutation site in this pedigree.
ObjectiveTo explore the light response, retinal inflammation and apoptosis of the retinal ganglion cells (RGCs) 1 year after the new type of channelrhodopsin PsCatCh2.0 was transfected into the retina of rd1 mice. MethodsTwenty-four male rd1 mice were randomly divided into rd1 experimental group and rd1 control group, 12 mice in each group. 1.5 μl of recombinant adeno-associated virus (rAAV)2/2-cytomegalovirus (CMV)-PsCatCh2.0-enhanced green fluorescent protein (EGFP) was injected into the vitreous cavity 1 mm below the corneoscleral limbus of mice in the rd1 experimental group, and the same dose of recombinant virus was injected 2 weeks later at temporal side 1 mm below the corneoscleral limbus. One year after virus injection, the light response of RGCs expressing PsCatCh2.0 was recorded by patch clamp technique; the expression of PsCatCh2.0 in the retina was evaluated by immunofluorescence staining; the transfection efficiency of recombinant virus was evaluated by the transfection efficiency of virus and the number of RGCs. Hematoxylin-eosin staining was performed to measure the inner retinal thickness. Western blotting was used to detect the protein expression of nuclear factor (NF)-κB p65 in retina; real-time quantitative polymerase chain reaction was used to detect the relative expression of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and Bax mRNA. Terminal deoxynucleotidyl transferase kit was used to observe the apoptosis of retinal cells in each group of mice. ResultsOne year after the intravitreal injection of recombinant virus, PsCatCh2.0-expressing RGCs can still generate 30 pA photocurrent. The virus PsCatCh2.0-EGFP was mainly transfected into RGCs, and partly transfected into amacrine cells, almost no transfection was seen in bipolar and horizontal cells. There were no significant differences in the number of RGCs and thickness of the inner retina between the rd1 experimental group and the rd1 control group (F=14.35, 0.05; P＞0.05), while the rd1 experimental group NF-κB p65 protein expression, TNF-α and IL-6 mRNA quantification were significantly lower than those of rd1 control group (F=4.61, 5.91, 5.78; P＜0.05). The number of red fluorescent apoptotic cells in the retina of mice in the rd1 experimental group was less than that in the rd1 control group, and the Bax mRNA expression was lower than that in the rd1 control group, and the difference was statistically significant (F=7.52, P＜0.01). ConclusionOne year after intravitreal injection of recombinant virus, the PsCatCh2.0 expressing RGCs can still generate photocurrent. Long term transfection and expression of PsCatCh2.0 has no obvious cytotoxic effect on RGCs, nor it increases the inflammatory effect of the retina of rd1 mice with retinal degeneration.
ObjectiveTo observe the clinical characteristics of primary retinitis pigmentosa (RP) complicated with glaucoma.MethodsA retrospective clinical study. From June 2008 to March 2020, the diagnosis of primary RP were included in the diagnosis confirmed by the eye examination of West China Hospital of Sichuan University included 4794 eyes of 2432 patients. Among them, 4679 eyes (97.2%, 2364/2432) were in 2364 cases with RP alone, and 115 eyes were in 68 cases with RP combined with glaucoma (2.80%, 68/2432). All affected eyes underwent best corrected visual acuity (BCVA) and intraocular pressure examination. The BCVA examination was carried out using the international standard visual acuity chart, which was converted into the logarithmic minimum angle of resolution (logMAR) visual acuity during statistics. The 67 eyes of 40 patients with RP and glaucoma with complete follow-up data were analyzed to observe the proportion of different glaucoma types, logMAR BCVA, intraocular pressure and other clinical characteristics, as well as treatment methods and post-treatment intraocular pressure control. After treatment, the intraocular pressure ≤21 mm Hg (1 mm Hg=0.133 kPa) was regarded as intraocular pressure (IOP) control; ＞21 mm Hg was regarded as uncontrolled IOP.ResultsAmong the 67 eyes of 40 cases with complete follow-up data, 5 cases (7 eyes) with primary open-angle glaucoma (10.45%, 7/67), 56 cases (58 eyes) with angle-closure glaucoma (ACG) (86.57%, 58/67), 4 cases (4 eyes) with neovascular glaucoma (5.97%, 4/67), 2 of them had both ACG and neovascular glaucoma. Among 58 ACG eyes, 17 eyes were acute ACG (25.37%, 17/67), 21 eyes were chronic ACG (31.34%, 21/67), and 2 eyes were suspicious angle closure (2.99%, 2/67), lens dislocation secondary to angle-closure glaucoma in 8 eyes (11.94%, 8/67), chronic angle-closure glaucoma after anti-glaucoma surgery, intraocular lens shift in 5 eyes (7.46%, 5/67), 5 eyes (7.46%, 5/67) secondary to glaucoma with true small eyeballs. The logMAR BCVA 3.50 of the affected eye,＜3.50-＞2.00, ≤2.00-≥1.30,＜1.30-＞1.00, ≤1.00-0.52,＜0.52 were 9 (13.43%, 9/67), 30 (44.78%, 30/ 67), 7 (10.45%, 7/67), 4 (5.97%, 4/67), 11 (16.42%, 11/67), 6 (8.96%, 6/67) eyes, which correspond to mean intraocular pressure were 32.31±11.67, 30.15±14.85, 28.17±13.19, 31.50±17.25, 18.71±8.85, 14.12±4.25 mm Hg. Among 67 eyes, 37eyes (55.22%, 37/67), 18eyes (26.86%, 18/67), and 6 (8.96%, 6/67) eyes underwent surgery, medication alone, and peripheral iris laser perforation treatment, respectively. The treatment of 6 eyes was abandoned (8.96%, 6/67). Malignant glaucoma occurred in 3 eyes (8.11%, 3/37) after the operation, all of which were after trabeculectomy of the ACG eye. After treatment, intraocular pressure was controlled in 37 eyes (55.22%, 37/67), 19 eyes were not controlled (28.36%, 19/67), and 11 eyes were lost to follow-up (16.42%, 11/67).ConclusionsThe incidence of glaucoma in patients with primary RP is 2.80%. ACG is more common, and the combined lens dislocation or intraocular lens shift is more common.
ObjectiveTo analyze the subfoveal choroidal thickness in retinitis pigmentosa (RP) patients and to evaluate the correlation between the subfoveal choroidal thickness (SCT) and visual function. MethodsTotally 42 RP patients (84 eyes) and 49 age and diopter-matched normal controls (98 eyes) were enrolled in this study. All the patients were taken the enhanced depth imaging technique of optical coherence tomography (EDI-OCT) examination for the measurement of the SCT. The covariate analysis was used to analyze the interaction effect between age and group. Then the SCT was amended. The RP patients were examined by 30°visual field test (T32 or LVC program) and electroretinogram (ERG) test. 32 eyes examined by T32 program, 52 eyes examined by LVC program. The waveform of ERG, mean sensitivity (MS) and mean defect (MD) were recorded. The relationship of SCT, MS and MD were analyzed by Pearson correlation analysis. ResultsThe SCT of RP patients and controls were (223.12±69.59), (288.29±52.36) μm. The covariate analysis of covariance with different age group interaction was not statistically significant (F=1.619, P=0.205), as amended SCT of RP patients and controls were (217.34±6.60), (293.20±6.00) μm, respectively. The SCT was decreased in RP patients (t=7.042, P < 0.001). Among 84 eyes, bright cone response weaken in 35 eyes, scotopic rod response weaken in 31 eyes. The difference of SCT in different ERG waveform was not significant (t=-0.976, -1.584; P=0.332, 0.117). The MS and MD of 32 eyes using T32 program were (9.05±6.42), (18.84±6.30) dB, the SCT was (209.83±71.48) μm; the MS and SCT of 52 eyes using LVC program were (7.14±5.03) dB and (228.32±66.32) μm. The SCT was related to MS (r=0.494, P=0.003) and MD (r=-0.448, P=0.009) in eyes using T32 program. There was no correlation between SCT and MD in eyes using LVC program (r=-0.232, P=0.095). ConclusionsThe SCT of RP patients is thinner than that of normal controls. The SCT of RP patients is related to MS and MD of T32 program, but not correlated to ERG waveform and MS of LVC program.