ObjectiveTo observe the effect of lysophosphatidylcholine acyltransferase-1 (LPCAT1) deficiency on the structure and electrophysiology of the murine retina. MethodsRd11 mice (Lpcat1 homozygous mutant, n=60) and wild-type C57BL/6J mice (n=60) were used in this study. Immunohistochemistry was performed to determine the expression of LPCAT1 in the mouse retina. Retinas of rd11 mice and age-matched control mice at postnatal 3, 6, 9-day and 2, 4, 6, 8-week were paraffin embedded,sectioned and hematoxylin eosin stained, and full-field electroretinograms (F-ERG) were also recorded at these time points. Statistics were based on independent samples t-test. ResultsLPCAT1 was absent in rd11 mice retina. In wild-type C57BL/6J mice retina, LPCAT1 was expressed most strongly in the inner segment of photoreceptor cells, weak in the ganglion cell layer. Rd11 mouse exhibited retinal degeneration and eventual photoreceptor cell loss. Retinas of rd11 mice showed nearly half of the photoreceptor cells missing around postnatal week 4,and by 6-week after birth only two layers of nuclei remained. At postnatal week 8,nearly all photoreceptor cells were lost. Dark-adapted F-ERG showed reduced rod-driven response at 2 and 4 weeks of age, which was flattened by 6 and 8 weeks of age. By 2 weeks of age, no significant difference was found in b-wave amplitude between rd11 eyes [(72.8±15.6) μV] and C57BL/6J eyes [(105.2±21.1) μV] (t=-2.760, P=0.025). Compared with age-matched control mice [(231.8±32.0)μV], rod response of rd11 mice [(20.6±6.4) μV] decreased obviously at postnatal week 4 (t=-14.471, P=0.000). Cone response was nearly normal at 2 and 4 weeks of age but substantially reduced at 6 weeks of age, which was flattened by 8 weeks of age. At 2 and 4 weeks after birth, no significant difference was found in b-wave amplitude between rd11 eyes [(46.8±7.2), (78.0±8.2) μV] and C57BL/6J eyes [(42.8±6.4), (91.4±9.4) μV] (t=0.930, -2.401; P=0.379, 0.043). Compared with age-matched control mice [(116.2±12.9) μV], cone response of rd11 mice [(17.2±2.0) μV] decreased obviously at postnatal week 6 (t=-17.008, P=0.000). ConclusionThe layers of photoreceptor cells nuclei in rd11 mice decreases with age, and its F-ERG reflection is unusual.
Stargardt disease (STGD) is an inherited disorder of retinal pigment epithelium. Three genes have been found to be implicated in STGD including Abca4 (adenosine triphosphate-binding cassette, sub-family A, member 4), Elovl4 (elongation of very long chain fatty acids protein 4) and Prom1 (prominin-1). Target genes can be delivered to the retina by various methods such as lentivirus (LV) vectors, adeno-associated virus (AAV) vectors and non-viral nano-particles. The Abca4-/-, Elovl4-/- and Prom1-/- mice model are used to study the pathogenesis mechanism and treatment of STGD. Retinal function improved significantly upon gene therapy in these models. Based on these works using animal model, phase Ⅰ/Ⅱa clinical trial of Abca4-associated STGD gene therapy are underway. AsaLV vector, equine infectious anemia virus (EIAV) is used to carry the Abca4 gene. These studies will evaluate three dose levels of the EIAV vector for safety, tolerability and biological activity. Moreover, some preclinical attempts to deliver Abca4 via AAV have been made usingamodified AAV vectors because of the large size of the ABCA4 cDNA. The good responses in animal models render STGDavery attractive object for human gene therapy after the successful of the phase Ⅰ/Ⅱ clinical trials of Leber′s congenital amaurosis.
ObjectiveTo explore the clinical value of the soluble urokinase type plasminogen activator receptor (suPAR) level in bronchoalveolar lavage fluid (BALF) for evaluateting the disease severity and prognosis of severe community-acquired pneumonia (SCAP). MethodsEighty-four patients with SCAP were recruited as a SCAP group from the respiratory department, ICU and RICU between April 2014 and April 2016. According to their organ dysfunction, the SCAP patients were subdivided into a MODS group and a non-MODS group. Depending on the treatment response on the 7th day of treatment, they were subdivided into an effective group and an ineffective group. According to the survival condition within 28 days, they were subdivided into a survival group and a death group. Meanwhile, 50 cases with non-severe common community acquired pneumonia were recruited as a control group. On the admission day, all cases were evaluated by PSI score and APACHE Ⅱscore. The serum suPAR level were detected by ELISA on the 1st day in hospital. The suPAR and procalcitonin (PCT) levels in the patient's BALF and serum were detected on the 1st, 3rd, 7th day, discharge or death day. The symptoms and signs, biochemical and pulmonary imaging changes were also observed. ResultsThere were no differences in the sex, age, body weight, duration of pneumonia, or complicated diseases such as hypertension, coronary heart disease and cerebral vascular diseases between the SCAP group and the control group (all P > 0.05). The suPAR levels in serum and BALF of the SCAP group were higher than those of the control group with significant differences (all P < 0.05). The suPAR level in BALF was obviously higher than that in serum in the SCAP group with significant difference (P < 0.05), and slightly higher than that in serum in the control group with no significant difference (P > 0.05). The level of suPAR in BALF of the MODS group was significantly higher than that in the non-MODS group with significant difference (P < 0.05), but there was no significant difference in the PCT level between the two groups (P > 0.05). The suPAR level in the ineffective treatment group was significantly higher than that in the effective treatment group on the 7th day in hospital with significant difference (P < 0.05). The suPAR levels in BALF of the death group were higher than those in the survival group at each time point after admittion with significant difference (all P < 0.05), and the PCT levels had no significant difference between the two groups within 1 week of each time point (all P > 0.05). The suPAR level in BALF of the SCAP group was positively correlated with APACHEⅡ score and PSI score (r=0.578, P=0.0085; r=0.565, P=0.0071), and plasma PCT level was weakly correlated with the APACHEⅡ score and PSI score (r1=-0.0137, r2=-0.0152). ConclusionThe SuPAR level in BALF of patients with SCAP is closely related to the severity and prognosis, and can be used as an index to assess the severity and prognosis.