Objective To investigate the role of intraeellular Ca2+ and MERTK in the phagocytosis of human retinal pigment epithelial (RPE) cells, and reveal the relationship between MERTK and intraeellular Ca2+. Methods The euhured RPE cells were incubated with rod outer segments (ROS) at 37℃, the phagoeytosis was terminated at different incubation time points. The concentration of intraeellular Ca2+ was assayed by Fluro-3/AM loading methods combined with fluorescence microscope and CCD system, and the mRNA level of MERTK gene was measured by reverse transcription polymerase chain reaction (RT-PCR). Treating the RPE cells with stimulator (A23187)or inhibitor(verapamile)of intraeellular Ca2+ to observe the changes of MERTK gene expression. Results ROS adhered to hRPE cells at the 15th minute, and the ingestion saturated at the 24th hour. The concentration of intracellular Ca2+ increased at the 15th minute, and kept the high level in 24 hours. The level of MERTK mRNA increased at the 5th minute, and kept the high level duration the whole incubation. When RPE cells were treated by A23187, the expression of MERTK increased in a dose-dependent manner. After RPE cells was pretreated by A23187, the expression level of MERTK was higher in the proceeding incubation groups than which in the control group except at the 3rd hour. When RPE cells were treated by verapamil, the expression level of MERTK decreased in a dose-dependent manner. After RPE cells were pretreated by verapamil , the expression level of MERTK was lower in all the proceeding incubation groups than which in the control group (P<0.05). Conclusion MERTK gene and Ca2+ play an important role in sustaining RPE cells phagoeytizing ROS. As an up-stream regulator, the receptor tyrosine kinase MERTK keeps RPE cells phagocytizing ROS by starting the intracellular Ca2+.

In this study, the effect of cyclosporin A (CsA) eye drop on keratoconjunctivitis Sicca (KCS) and its mechanism were studied. The KCS models were established by injecting Pertussis vaccine, complete freunds adjuvant (CFA) and antigen of conjunctiva from isotype mice. Then the KCS models were treated with cyclosporin A eye drop. Changes in breaking-up time (BUT), lacrimal secretion in 30 min and diversion in 24 h were measured. The percentage of beaker cells, the lymphocytic infiltration in conjunctiva were observed. The expression levels of Aquaporin-3(AQP3) in conjunctiva epithelial cells, beaker cells and accessory lacrimal gland were immunohistochemically detected. The results showed that there were significant differences in BUT, the percentage of beaker cells, lacrimal secretion in 30 min, the lymphocytic infiltration and the expression of AQP3 between the experimental group and an control group. It was concludedthat CsA eye drop exerts marked therapeutic effect on KCS by inhibiting T lymph cells, increasing the goblet cells and AQP3 expression in conjunctiva.

To investigate the mutation site of pathogenic gene in patients with hypertrophic cardiomyopathy (HCM) and to analyze the relationship between the genotype and clinical phenotype. Methods: Targeted exon capture sequencing was conducted in a HCM proband for 30 coding exons related HCM gene by all exon amplification and high-throughput sequencing. Furthermore, Sanger sequencing was performed in other family member and in 200 healthy volunteers for verification. The familial investigation included in clinical presentation, physical examination, electrocardiogram and echocardiography. Results: There were 3/6 blood relatives carrying cardiac myosin-binding protein gene MyBPC3 G772A heterozygous mutation, the mutation site was at 258 amino acid of MyBPC3 as glutamic acid (Glu) was substitute to lysine (Lys), such mutation was not found in rest of family member and not in healthy volunteers. The onset of proband and her daughter was rather late, they had palpitation and chest tightness; echocardiography showed interventricular septum basal segment thickening (16-18) mm. Proband was complicating paroxysmal ventricular tachycardia, malignant arrhythmia and heart failure, the maximum pressure gradient of left ventricular outflow was 56 mmHg, which with the high risk for sudden death. Conclusion: Comprehensive gene test has been helpful for clinical stratification, early diagnosis and treatment. MYBPC3 site mutation c.G772A might be the pathogenic mutation in that specific HCM family.