In recent years, the subthreshold micropulse laser is a kind of laser mode which is characterized by long intermittence. It achieves effective therapeutic effect while minimizes the damage to tissues. At present, it has been used to treat diabetic macular edema. Early studies suggested that the laser selectively acts on retinal pigment epithelial cells to reduce macular edema by regulating the expression of inflammatory biomarkers, growth factors, heat shock proteins and other substances. In recent years, with the development of research, more and more emphasis has been placed on the role of retinal glial cells. Müller cells are also considered as one of the target cells affected by micropulse laser, but there is no evidence of direct or indirect effects of micropulse laser on Müller cells. In the near future, it is expected that we will have more clinical evidence to confirm the target cells of the micropulse laser, which may be further confirmed by in vitro experiments through Müller cells or Müller cells co-cultured with retina pigment epithelium cells, so as to make a more detailed statement on the mechanism of it.
ObjectiveTo observe the relationship between the response to anti-vascular endothelial growth factor (VEGF) drug treatment and single nucleotide polymorphism (SNP) genotype in patients with wet age-related macular degeneration (wAMD). MethodsA retrospective clinical study. From August 2019 to September 2020, 103 eyes of 103 wAMD patients diagnosed in Tianjin Medical University Eye Hospital were included in the study. Among them, there were 59 males (57.28%, 59/103) and 44 females (42.72%, 44/103); the average age was 68.74±7.74 years. The standard logarithmic visual acuity chart was used to detect the Best Corrected Visual Acuity of the affected eye and converted to the logarithmic minimum angle of resolution (logMAR) visual acuity during statistics. Optical coherence tomography was used to detect the central retinal thickness (CRT) of the affected eye. At the same time, the patient's high-density lipoprotein cholesterol (HDL-C) was tested. All eyes were treated with intravitreal injection of anti-VEGF drugs once a month for 3 months. Before the initial treatment, peripheral venous blood from the patient were collected. Interleukin-8 (IL-8), complement C3 gene (C3), complement factor H (CFH), liver lipase (LIPC), cholesterol ester transfer protein (CETP), ATP binding cassette subfamily a member 1 (ABCA1), lipoprotein lipase (LPL), fatty acid desaturation gene cluster (FADS1) SNP. According to gene frequency, genotypes are divided into wild type and mutant type were detected. Qualitative data such as the frequency difference of the genotype distribution in the clinical phenotype and the Hardy-Weinberg equilibrium of the genotype distribution were compared with the Chi-square test or Fisher's exact test. ResultsThere were fewer CRT responders in IL-8 rs4073 mutant (TA+AA) patients than wild-type (TT) [odds ratio (OR)=0.310, 95% confidence interval (CI) 0.106-0.910, P＜0.05). Among them, after the drug stratification test, the proportion of patients with IL-8 rs4073 locus TT genotype in the conbercept treatment group was less CRT non-responders (OR=0.179, 95% CI=0.034-0.960, P=0.033). Patients with LIPC rs2043085 mutant (CT+TT) with BCVA increased ≥0.2 logMAR are more likely than wild-type (CC) (OR=3.031, 95% CI 1.036-8.867, P＜0.05); HDL-C level was significantly lower Compared with wild type (CC), the difference was statistically significant (t=2.448, P=0.016). There was no significant difference in logMAR BCVA and CRT between IL-8 rs4073, LIPC rs2043085 mutant and wild-type patients before treatment (IL-8 rs4073: Z=－0.198, －1.651; P=0.843, 0.099; LIPC rs2043085: Z=－0.532, －0.152; P=0.595, 0.879). C3 rs 225066, CFH rs800292, CETP rs708272, ABCA1 rs1883025, FADS1 rs174547, LPL rs12678919 have no correlation with anti-VEGF drug treatment response. Conclusions Patients with wAMD are treated with anti-VEGF drugs. Those with IL-8 rs4073 locus A genotype may be less responsive to CRT. LIPC rs2043085 locus T genotypes may be relatively more responsive to BCVA.