Objective:To prepare rabbit polyclonal antibodies against respiratory syncytial virus (RSV) N protein and use them as the detection antibodies to establish a N-ELISA-based method for rapid detection of neutralizing antibodies.Methods:A plasmid of pET30a-N for the expression of RSV N protein was constructed. After purification, the protein was immunized into New Zealand rabbits to prepare polyclonal antibodies, which were used as the detection antibodies. Positive serum samples were diluted and used to neutralize RSV (100 TCID 50/well). Hep-2 cells were inoculated and cultured, and then the cells were fixed with 80% acetone. ELISA was performed to detect RSV N protein in infected cells. When the absorbance value of a well was below the cut-off value, it was regarded as the positive well in the neutralization test. The highest dilution of a positive well serum was the neutralizing antibody titer. After optimizting the antibody dilution, detection time, cell density and the duration of neutralization, the method for neutralizing antibody detection was established based on N-ELISA. The established method was verified by analyzing the influences of different cell generations and edge effects, and calculating the accuracy, repeatability and precision. The correlation between the established method and microneutralization method was analyzed by detecting human RSV IgG-positive serum. Results:The plasmid pET30a-N was successfully constructed, and the expressed N protein showed high purity and good specificity. After the third immunization, the antibody titer in rabbit serum was 1∶51 200, and the antibodies could specifically bind to RSV. The prepared rabbit anti-RSV N polyclonal antibodies had a titer of 1∶51 200, and showed good specificity. The neutralizing antibodies could be detected on day 4 with the established method, and the duration of neutralization was shortened to 30 min. Cell generations and the position of wells in the 96-well plate (edge well and non-edge well) had no significant effect on the method, and the repeatability, precision and accuracy of the method were good. In the detection of 64 RSV IgG-positive human serum samples by the established method and microneutralization method, the correlation coefficient was 0.929 6, indicating a good positive correlation between the two methods.Conclusions:A N-ELISA-based method for rapid neutralizing antibody detection is successfully established, which can be used to evaluate the serum antibody level after RSV vaccination.

Objectives:To explore health-related quality of life (HRQoL) and identify its associated variables in Chinese patients with Philadelphia-negative myeloproliferative neoplasms (MPNs) .Methods:In this cross-sectional study, anonymous questionnaires were distributed to adult patients with MPNs to assess symptom burden measured by MPN-10 and HRQoL measured by Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) and the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) .Results:The data from 1405 respondents with MPNs, including 645 (45.9%) with essential thrombocythemia (ET) , 297 (21.1%) with polycythemia vera (PV) , and 463 (33.0%) with myelofibrosis (MF) , were analyzed. 646 (46.0%) respondents were male. The median age was 56 (range, 18-99) years. The mean MPN-10 scores were 13.0±12.7, 15.0±14.7, and 21.0±16.6 ( P<0.001) , and the physical component summary (PCS) and mental component summary (MCS) scores were 48.0±8.5, 47.0±9.0, and 42.0±10.0 ( P<0.001) and 51.0±11.0, 50.0±10.8, and 49.0±11.1 ( P=0.002) for respondents with ET, PV, and MF, respectively. Respondents with MF reported the lowest score of physical functioning, role functioning, emotional functioning, cognitive functioning, social function, and global health status (all P<0.01) and the highest score of fatigue, pain, dyspnea, appetite loss, diarrhea, and financial problems (all P<0.05) in EORTC QLQ-C30. Multivariate analyses revealed that higher MPN-10 scores were significantly associated with lower PCS (-0.220 to -0.277, P<0.001) and MCS (-0.244 to -0.329, P<0.001) scores; increasing age (-1.923 to -4.869; all P<0.05) , lower PCS score. Additionally, comorbidity (ies) , symptom at diagnosis, splenomegaly, anemia, unknown driver gene, and higher annual out-of-pocket cost were significantly associated with lower PCS and/or MCS scores. However, age ≥ 60 years, urban household registration, concomitant medication, and receiving ruxolitinib therapy in respondents with MF were associated with higher MCS scores. Weak correlations were found between MPN-10 score (except the subscale of appetite loss and constipation) and EORTC QLQ-C30 score in majority of subscales in respondents with ET (| r| = 0.193-0.457, all P<0.001) , PV (| r| = 0.192-0.529, all P<0.01) , and MF (| r| = 0.180-0.488, all P<0.001) , respectively. Conclusions:HRQoL in patients with MPN was significantly reduced, especially in patients with MF. Sociodemographic and clinical variables were significantly associated with the HRQoL in patients with MPNs.

Objectives:To investigate the clinical and genetic features of young Chinese patients with myeloproliferative neoplasms (MPN) .Methods:In this cross-sectional study, anonymous questionnaires were distributed to patients with MPN patients nationwide. The respondents were divided into 3 groups based on their age at diagnosis: young (≤40 years) , middle-aged (41-60 years) , and elderly (>60 years) . We compared the clinical and genetic characteristics of three groups of MPN patients.Results:1727 assessable questionnaires were collected. There were 453 (26.2%) young respondents with MPNs, including 274 with essential thrombocythemia (ET) , 80 with polycythemia vera (PV) , and 99 with myelofibrosis. Among the young group, 178 (39.3%) were male, and the median age was 31 (18-40) years. In comparison to middle-aged and elderly respondents, young respondents with MPN were more likely to present with a higher proportion of unmarried status (all P<0.001) , a higher education level (all P<0.001) , less comorbidity (ies) , fewer medications (all P<0.001) , and low-risk stratification (all P<0.001) . Younger respondents experienced headache (ET, P<0.001; PV, P=0.007; MF, P=0.001) at diagnosis, had splenomegaly at diagnosis (PV, P<0.001) , and survey (ET, P=0.052; PV, P=0.063) . Younger respondents had fewer thrombotic events at diagnosis (ET, P<0.001; PV, P=0.011) and during the survey (ET, P<0.001; PV, P=0.003) . JAK2 mutations were found in fewer young people (ET, P<0.001; PV, P<0.001; MF, P=0.013) ; however, CALR mutations were found in more young people (ET, P<0.001; MF, P=0.015) . Furthermore, mutations in non-driver genes (ET, P=0.042; PV, P=0.043; MF, P=0.004) and high-molecular risk mutations (ET, P=0.024; PV, P=0.023; MF, P=0.001) were found in fewer young respondents. Conclusion:Compared with middle-aged and elderly patients, young patients with MPN had unique clinical and genetic characteristics.