Cilia are hair-like protuberance on cells of the human body that play a vital role in organs generation and maintenance. Abnormalities of ciliary structure and function affect almost every system of the body, such as the brain, eyes, liver, kidney, bone, reproductive system and so on. Retinal photoreceptor cells are one of sensory neurons which convert light stimuli into neurological responses. This process, called phototransduction, takes place in the outer segments (OS) of rod and cone photoreceptors. OS are specialized sensory cilia, and disruptions in cilia genes, which are causative in a growing number of non-syndromic retinal dystrophies, such as retinitis pigmentosa, Leber’s congenital amaurosis. These syndromes are genetically heterogeneous, involving mutations in a large number of genes. They show considerable clinical and genetic overlap. At present, there are few researches on retinal ciliopathies and clinical treatment strategy. This review shows a comprehensive overview of ciliary dysfunction and visual development related diseases, which contributes to understand the characteristics of these diseases and take early intervention in clinic.
ObjectiveTo observe the changes of circumpapillary retinal nerve fiber layer (CP-RNFL) thickness and optic disk parameters in retinitis pigmentosa (RP) eyes. MethodsProspective clinical case-control study. A total of 25 patients (42 eyes) with RP were in the RP group, and 42 age matched healthy subjects (84 eyes) in the control group. All subjects underwent optical coherence tomography (OCT) examination, in which 37 eyes with 3D optic disk scanning and 5 eyes with circle optic disk scanning. The parameters included average thickness of entire CP-RNFL, thickness of nasal, superior, temporal and inferior quadrant of CP-RNFL, disc area, disc cup area, rim area, cup/disc (C/D) area ratio, C/D horizontal diameter ratio, C/D vertical diameter ratio, disc cup volume and disc rim volume. ResultsThe average thickness and the thickness of temporal and nasal quadrants of CP-RNFL in RP group were significantly thicker than the control group (t=2.27, 3.73, 6.44; P=0.027, 0.00, 0.00), while the thickness of inferior and superior areas were the same as control group(t=-1.49, -1.19; P=0.14, 0.24). The disc area, disc cup area, C/D area ratio, C/D horizontal diameter ratio, C/D vertical diameter ratio, disc cup volume in RP group were significantly bigger than control group (P < 0.05), while rim area and rim volume were not significant differences (t=1.75, 0.40; P=0.08, 0.59). ConclusionIn comparison with the healthy subjects, the average thickness and temporal and nasal areas of CP-RNFL in RP eyes were thicker, and the disc area, disc cup area, C/D area ratio, C/D horizontal diameter ratio, C/D vertical diameter ratio, disc cup volume in RP eyes were bigger.
Objective To observe the expression and investigate the significance of suppressor of cytokine signaling (SOCS) in peripheral blood mononuclear cells (PBMC) of experimental autoimmune uveitis (EAU). Methods 100 Lewis rats were immunized with interphotoreceptor retinoid-binding protein (IRBP) to induce EAU animal model, and they were divided into control group and treatment group randomly. The treatment group was administered cyclosporine A 20mg/（kgmiddot;d）after 1 to 28 days of immunization; the control group received saline buffer at equal quantity. All eyes were evaluated by slit-lamp microscopy before and after 7, 14, 21, 28 days of immunization; IL-4，IL-12，IFN-gamma; in the serum were measured by enzyme linked immunosorbent assay(ELISA); the SOCS mRNA and protein level in PBMC were measured by quantitative polymerase chain reaction (q-PCR) and western blot. Results The inflammation was most obvious at 14 days after immunization. The control group showed obvious iridocyclitis; the treatment group showed mild anterior chamber inflammation but no posterior synechia and hypopyon. The highest level of IL-12 and IFN-gamma; were observed at 14 days after immunization, followed by decline to the baseline at 28 days after immunization in control group; the highest level of IL-12 and IFN-gamma; were found at 14 days after immunization in treatment group, but the level was lower than control group obviously. Compared with the level before immunization, there are no differences at other time-point. The concentration of IL-4 decreased indistinctly in control group but increased in treatment group. SOCS1、Both of SOCS1 and SOCS5 increased to the highest level at 14 days after immunization, as 4.05 and 383 times of preimmunization in control group respectively, as 1.15 and 1.16 times in treatment group respectively. The CIS and SOCS3 mRNA increased lightly in two groups and treatment group milder than control group. Marked increased expression of SOCS1 and SOCS5 protein was detected at 7, 14, 21days than preimmunization, both of CIS and SOCS3 protein were significantly increased on 14, 21 days in control group; only SOCS1 protein was significantly increased on 14 days in treatment group and there are no differences at other time-point compared to pre-immunization. Conclusion Up-regulation of SOCS1 and SOCS5 expression maybe related to intensive response of Th1 in the development of EAU. Mild up-regulation of CIS and SOCS3 maybe associated with intensive response of Th2 which against the reaction of Th1 to carry out the dynamic immune balance.
ObjectiveTo observe and analyze the pathogenic genes and clinical phenotype characteristics of retinitis pigmentosa sinepigmento(RPSP). MethodsA retrospective clinical study. Two patients (proband) and five family members from two RPSP families admitted to Xiamen Eye Center of Xiamen University in December 2022 and Shenzhen Eye Hospital in July 2023 were included in the study. Two families have no blood relationship and were both Han Chinese. Detailed ocular and systemic medical history and specialized examinations were performed for all members, including color fundus photography, fundus autofluorescence (FAF), and full field electroretinogram (ff-ERG) examination. The peripheral venous blood of all members was collected, and genomic DNA was extracted. Pathogenic genes and their loci were screened using whole exome high-throughput sequencing technology. Sanger sequencing was used to verify the pathogenic genes in the two pedigrees. The pathogenicity of candidate variants was evaluated according to the American Society for American College of Medical Genetics and Genomics (ACMG) classification criteria and guidelines for genetic variants. ResultsThe two probands were male, aged 9 and 7 years, respectively. The main complaint was poor binocular vision for 6 and 3 years and poor treatment effect of amblyopia. The proband (Ⅱ2) in family 1 had a pale red color on the optic disc, with leopard-like changes in the posterior pole and thinner retinal arteries. FAF showed mottled fluorescence attenuation outside the macular vascular arch. There was no significant waveform in both bright and dark visual responses of ff-ERG. He also had 6-toed deformity of both feet, renal cysts, and a slightly overweight body. The clinical diagnosis was non-pigmentary retinitis pigmentosa. The proband of family 2 (Ⅱ1) had poor binocular vision in a dark environment and had atrophy lesions on the nasal side of the optic disc and leopard print like changes in the fundus. FAF showed uneven enhancement in the fovea. ff-ERG showed severe abnormalities in dark and light response, with significant decrease and delay in b-wave amplitude and latency. He had no other systemic abnormalities. The clinical diagnosis was binocular RPSP. There were no abnormal ocular and systemic manifestations in the two family members. Gene sequencing revealed a homozygous mutation (c.534+1G>T) of BBS2 gene, which was inherited from the mother and father respectively. Based on clinical manifestations and genetic testing results, the final diagnosis was Bardet Biedl syndrome. The genetic sequencing results confirmed a novel compound heterozygous mutation (c.950T>G: p. Leu317Arg missense mutation and c.849+1G>C splicing mutation) of BBS7 gene. His father (Ⅰ1) and mother (Ⅰ2) carried M1 heterozygous variants. Combined with the clinical manifestations and genetic testing results, the final diagnosis was Bardet-Biedl syndrome (BBS). Family 2 proband (Ⅱ1) carried the BBS7 gene C.950T>G (p.Leu317Arg) (M2) missense variation and C.849 +1G>C (M3) splice site variation. His father (Ⅰ1) and mother (Ⅰ2) carried M3 shear site variation and M2 missense variation, respectively. The two families all fit the autosomal recessive inheritance pattern, and the genotype and clinical phenotype were coseparated. According to ACMG guidelines, M1, M2 and M3 were all identified as possible pathogenic variants. ConclusionsBBS2 gene M1 homozygous variation and BBS7 gene M2, M3 complex heterozygous variation are the possible pathogenic genes in family 1 and family 2, respectively. Two families are affected by BBS and RPSP, respectively.
Objective To observe the expression of cyclin dependent kinase 5 (Cdk5) and p25 in the pathogenesis of retinitis pigmentosa (RP) in Royal College of Surgeon (RCS) rats and its relationships with apoptosis. To explore the mechanism of Cdk5 and p25 induced photoreceptor apoptosis in the pathogenesis of RP. Methods Retinas of RCS and RCS-rdy+ rats were obtained at the ages of postnatal day 17, 25, 35, 60. The retinal structure and thickness of outer nuclear layer were measured by optical microscopy. The expression of Cdk5, p25, cleave-caspase 3 in the retina was evaluated by immunohistochemistry. The protein expression of cleave-caspase 3 in the retina was determined by Western blot. The apoptosis of retinal cells was examined by terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL). The mean absorbance value of apoptotic cells was analyzed by SPSS 17.0 software. Results The retinal thickness of the RCS rats was significantly reduced in comparison to the RCS-rdy+ rats as the postnatal days progressed, particularly in the layer of rods and cones and the outer nuclear layer. The expression level of Cdk5, p25, cleave-caspase 3 of RCS rats increased from postnatal 17 days to postnatal 35 days, while decreased on postnatal 60 days; but there was no obvious change of above indexes in RCS-rdy+ rats. The protein expression of cleave-caspase 3 in the RCS rats was significantly increased with progression of postnatal days to postnatal 35; but there was no obvious similar change in RCS-rdy+ rats. The results of TUNEL showed that the apoptotic cells significantly increased in the outer nuclear layer of RCS rats from postnatal 17 days to postnatal 35 days, while decreased on postnatal 60 days; but there was no obvious change of above index in RCS-rdy+ rats. This study showed that there were significant correlations between the following variables: Cdk5 expression and p25 expression, Cdk5 expression and cleave-caspase 3 expression, Cdk5 expression and apoptotic cells, p25 expression and cleave-caspase 3 expression, p25 expression and apoptotic cells, cleave-caspase 3 expression and apoptotic cells. The partial correlation coefficients were 0.949, 0.808, 0.959, 0.887, 0.979, 0.852, respectively and the P value was 0.000. Conclusions The apoptotic cells significantly increases and the expression level of Cdk5, p25, cleave-caspase 3 of RCS rats increases from postnatal 17 days to postnatal 35 days. The tendency of apoptotic cells to increase is consistent with the change of Cdk5, p25, cleave-caspase 3 expression. The apoptosis of photoreceptor cells is related to increasing expression of Cdk5 and p25 in RCS rats. Cdk5 may be involved in the development of RP in RCS rats.
Objective To observe the mutifocal electroretinogram (mfERG) characteristics of rod and cone cells in patients with retinitis pigmentosa (RP) and to evaluate the function of photosensory cell.Methods The mfERG recording technique for rod cell in eight normal subjects (eight eyes) were established and the influence of different brightness lightstimulus in P1 wave amplitude were analyzed. The cone and rod cells mfERG of 38 eyes in 19 patients were recorded and then calculated positive ratio from local signalnoise ratio. The average visual acuity and P1 wave amplitude density of cone mfERG in different types were compared and statistically analyzed. Meanwhile, the changes in P1 wave amplitude of cone and rod mfERG in four quadrants also compared and analyzed. Results Rod cell mfERG in normal subjects can be recorded stably by using blue flashes with low light intensity as 0.04 cd/m2. In patients with RP, the cone and rod cells mfERG can be detectd 65.79% and 10.51% respectively. P1 wave amplitude density in type I of cone cell mfERG was significantly higher than that in type II (t=5.21,P=0.000). There were no differences in average visual acuity (t=1.15, P=0.612). P1 wave amplitude density in type I was negatively related to logMAR visual acuity （r=-0.48，P=0.04）.The comparison of rod and cone cells mfERG in local wave characteristics showed that P1 wave amplitude densities had spatial relationship in each area. Conclusions The results suggested highly variable central responses in cone cell in RP patients, higher positive recorded ratio in cone cell than rod cell and spatial correspondence between the function of reserved cone and rod cells.
Objective To investigate the cellular phenotype involved in experimental autoimmune uveoretinitis (EAU) and apoptosis of infiltrating cells in this inflammation． Methods Immunohistochemical staining and in situ apoptosis staining were performed using monoclonal antibodies to monocytes and macrophages (EDI),MHC calss -II antigen (OX6),T lymphocytes (R73) and TACS 1 Klenow kit on both ocular sections and wholemounts of 16 Lewis rats after immunization with interphotoreceptor retinod-binding protein(IRBP). Results EAU was induced in 12 of 16 Lewis rats with a clinical inflammation score being 1.29plusmn;0 .7.Influx of monocytes,lymphocytes and MHC class II+ cells into the uvea and retina was noted after immunization with IRBP.Apoptosis of infiltrating cells was observed in the uvea and retina and more apoptotic cells were present in the iris and ciliary body compared with the choroid and retina. Conclusion A number of cells including monocytes,macrophages,lymphocytes and MHC class II+ cells are involved in EAU induced by IRBP.Apoptosis of infiltrating cells occurs at early stage of EAU,which may greatly contribute to the rapid regression of the inflammation induced by IRBP. (Chin J Ocul Fundus Dis，2000，16：1-70)
Objective To observe the efficacy of the anti-tumor necrosis factor-alpha; monoclonal antibody (TNF-alpha; MCAb) in the treatment of experimental autoimmune uveoretinitis (EAU). Methods EAU animal models were induced by interphotoreceptor retinoid-binding protein (IRBP) R16 peptide with immunization. The rats were divided into 2 groups according to the injection times. TNF-alpha; MCAb was administered intravenously on day 6 or 4, 6 and 8 post-immunization respectively, and then to observe the clinical expression by slit-lamp microscope. Meanwhile, take the rats which did not accept TNF-alpha; MCAb as control group. Delayed type hypersensitivity (DTH) responses were measured on day 13 post-immunization of IRBP R16; the rats were killed on day 14 post-immunization of IRBP R16, and then enucleated the eyes for histopathological examination. To detect the cytokine level of IFN-gamma;, IL-4 in serum and IFN-gamma; in aqueous humor by enzyme-liked immunosorbent assay (ELISA) on day 14 post-injection. The hyperplasia responses of antigen specific lymphocyte of draining lymph node cells were detected. Results The TNF-alpha; MCAb group had mitigated ocular inflammation and decreased pathological grades compared with the control group; the IFN-gamma; concentrations in aqueous humor and serum were decreased, IL-4 was increased in serum; DTH responses were decreased; the hyperplasia responses of draining lymphocytes to IRBP R16 peptide were decreased, all the differences were statistically significant (P＜0.01). The rats accepted TNF-alpha; MCAb thrice had much better curative effect than the rats injected once (P＜0.05). Conclusions Injection of TNF-alpha; MCAb can inhibit ocular inflammation and specific immune cells of EAU remarkably and change the Th1/Th2 balance. Many times injections of TNF-alpha; MCAb were more effective than once.
Objective To investigate the expression and significance of T-bet in experimental autoimmune uveoretinitis (EAU). Methods EAU was induced in 24 Lewis rats by immunization with retinal S-antigen (50 μg) and complete Freund′s adjuvant, and another 4 rats were the healthy control. The rats with EAU were executed 7, 12, 15, 21 days after immunization, respectively. Immunohistochemical single and double staining were performed using monoclonal antibodies of T-bet or CD4 on the ocular wholemounts and the consecutive sections of the eye and spleen from both 24 immunized Lewis rats and 4 normal controls. The positive cells were counted under the optic microscope and the data were analyzed by SPSS 11.0 statistic software. Results A few T-bet positive cells were observed in the normal ocular tissues and spleen. The expressions of T-bet in the iris, retina, and spleen increased 7 days after immunization, reached the peak at the 15th day, and decreased at the 21st day, which were higher than those in the control. Double staining on the consecutive sections revealed that most of the T-bet positive cells were positive for CD4 monoclona l antibody. Conclusion T-bet may affect the occurrence of EAU by activating Th1 cells. (Chin J Ocul Fundus Dis，2004，20：172-174)
Retinitis pigmentosa (RP) is a group of hereditary blinding fundus diseases caused by abnormalities in photoreceptors of the retina. RP is highly heterogeneous in hereditary and cdinical phenotypes. It can be divided into simple type RP and syndrome type RP. The main inheritance patterns are autosomal dominant, autosomal recessive inheritance and X-linked inheritance. With the popularization and clinical application of gene sequencing technology, more and more disease-causing genes have been discovered, and these genes are mainly expressed in photoreceptor cells and retinal pigment epithelial cell. ln-depth understanding of RP pathogenic genes not only provides a theoretical basis for RP diagnosis and genetic counseling, but also provides guidance for RP gene therapy.