Diagnostic Indexes of a Rapid IgG/IgM Combined Antibody Test for SARS-CoV-2

[Abstract]O_ST_ABSObjectiveC_ST_ABSCoronavirus disease 2019 (COVID-19) has become pandemic in the world. The need for IgG-IgM combined antibody test is booming, but data on diagnostic indexes evaluation was inadequate. The aim of this study was to evaluate diagnostic indexes of a rapid IgG-IgM combined antibody test for SARS-CoV-2. MethodsA total of 179 patients were enrolled. Serum were collected for IgG-IgM combined antibody test and corresponding nasal and pharyngeal swab specimens were collected for SARS-CoV-2 RT-PCR. According to SARS-CoV-2 RT-PCR results, patients under study were categorized as PCR positive group in 90 patients and PCR negative group in 89 patients. Results1. Of the 90 PCR positive samples, 77 were tested positive by SARS-CoV-2 IgG-IgM test kit, yielding a sensitivity of 85.6%. Meanwhile, of the 89 PCR negative sample, 8 samples were detected positive, resulting in a specificity of 91%. Positive predictive value, negative predictive value and accuracy of this test kit was 95.1%, 82.7%, and 88.3%, respectively. Kappa efficiency between IgG/IgM test kit and RT-PCR were 0.75. 2. Accuracy in mild/common and severe/critical subgroup were 73.9% and 97.7%, respectively. Accuracy in clinical confirmed, suspected cases and other disease subgroups were 70%, 60%, and 100%, respectively. 3. Patients were further divided into 0 - 7, 8 - 15 and >= 16 groups according to the time from illness onset to sample collection. Sensitivity, specificity and accuracy in these three groups were 18.8%, 77.8% and 40%; 100%, 50% and 87.5%; 100%, 64.3%, and 93.9, respectively. ConclusionThe sensitivity and specificity of this ease-of-use IgG/IgM combined test kit were adequate, plus short turnaround time, no specific requirements for additional equipment or skilled technicians, all of these collectively contributed to its competence for mass testing. At the current stage, it cannot take the place of SARA-CoV-2 nucleic acid RT-PCR, but can be served as a complementary option for RT-PCR. The combination of RT-PCR and IgG-IgM combined test kit could provide further insight into SARS-CoV-2 infection diagnosis.

Detectable serum SARS-CoV-2 viral load (RNAaemia) is closely associated with drastically elevated interleukin 6 (IL-6) level in critically ill COVID-19 patients

BackgroundAlthough the SARS-CoV-2 viral load detection of respiratory specimen has been widely used for novel coronavirus disease (COVID-19) diagnosis, it is undeniable that serum SARS-CoV-2 nucleic acid (RNAaemia) could be detected in a fraction of the COVID-19 patients. However, it is not clear that if the incidence of RNAaemia could be correlated with the occurrence of cytokine storm or with the specific class of patients. MethodsThis study enrolled 48 patients with COVID-19 admitted to the General Hospital of Central Theater Command, PLA, a designated hospital in Wuhan, China. The patients were divided into three groups according to the Diagnosis and Treatment of New Coronavirus Pneumonia (version 6) published by the National Health Commission of China. The clinical and laboratory data were collected. The serum viral load detection and serum IL-6 levels were determined. Except for routine statistical analysis, Generalized Linear Models (GLMs) analysis was used to establish a patient status prediction model based on real-time RT-PCR Ct value. FindingsThe Result showed that cases with RNAaemia were exclusively confirmed in critically ill patients group and appeared to reflect the illness severity. Further more, the inflammatory cytokine IL-6 levels were significantly elevated in critically ill patients, which is almost 10-folds higher than those in other patients. More importantly, the extremely high IL-6 level was closely correlated with the incidence of RNAaemia (R=0.902) and the vital signs of COVID-19 patients (R= -0.682). InterpretationSerum SARS-CoV-2 viral load (RNAaemia) is strongly associated with cytokine storm and can be used to predict the poor prognosis of COVID-19 patients. Moreover, our results strongly suggest that cytokine IL-6 should be considered as a therapeutic target in critically ill patients with excessive inflammatory response.

Lymphopenia predicts disease severity of COVID-19: a descriptive and predictive study

BackgroundCoronavirus disease-2019 (COVID-19) is a rapidly escalating epidemic caused by SARS-CoV-2. Identification of a simple and effective indicator to assess disease severity and prognosis is urgently needed. MethodsDynamic changes of blood lymphocyte percentage (LYM%) in 15 death cases, 15 severe cases as well as 40 moderate cases of COVID-19 patients were retrospectively analyzed. A Time-LYM% model (TLM) was established according to the descriptive studies and was validated in 92 hospitalized cases. ResultsResults from death and severe cases showed that LYM% in blood tests were inversely associated with the severity and prognosis of COVID-19. LYM% in moderate type of patients with COVID-19 remained higher than 20% 10-12 days after symptom onset. In contrast, LYM% was lower than 20% in severe cases. However, LYM% in severe cases was higher than 5% 17-19 days after the onset of the disease, while it fell below 5% in death cases. Accordingly, we established a Time-LYM% model (TLM), which was validated as an independent criterion of disease classification in another 92 hospitalized patients with COVID-19. ConclusionLymphopenia can be used as an indicator of disease severity and prognosis of COVID-19 patients. TLM is worth of application in the clinical practice.

Correlation among the Positive Rate of Autoantibody,HCV Load and the Status of Liver Function in Patients Infected HCV / 现代检验医学杂志

Objective To analyze the correlation between the positive rate of autoantibody and hepatitis C virus load and the relationship between the positive incidence and the status of liver function in patients infected HCV.Methods 168 patients infected hepatitis C virus were included,to detect serum autoantibody,HCV loads and liver function file.And 129 healthy controls were collected to test the serum autoantibody.Using the Chi-square test to analyze the count data,and performing student test or Nonparametric test to study measurement data,compared the positive rate of autoantibody in patients with HCV and that in healthy controls.Analyzed the correlation among the positive incidence of autoantibody,HCV load and the status of liver function in patients infected HCV,and studied the relationship of the positive rate of autoantibody with age and also with gender of the patients.Results The positive rate of autoantibody in patients with HCV was 35.12%(59/168),in which ANA accounted for 33.93%,SMA took up 2.98%,AMA-M2 made up 1.80% and anti-LKM1 1.20%.No patient existed LC-1 or SLA/LP in his/her serum.The total positive rate of autoantibody and ANA both were higher in pa-tients than in healthy controls (χ2=23.179,P=0.000;χ2=21.360,P=0.000).There existed no significant difference in the levels of HCV load,total bilirubin (TBil),ALT and AST between the patients whose autoantibody examinations were positive and those who were negative in autoantibody test (χ2=0.113,P=0.945;Z=-1.087,P=0.277;Z=-1.356,P=0.175;Z=-0.153,P=0.878).The positive rate of autoantibody not correlated with the gender (χ2=2.897,P=0.089), but related to the age (t=3.274,P=0.001)of the patients.There existed significant difference in the levels of ALT,AST and the age between the patients HCV RNA negative and those HCV RNA positive (Z=-6.430,P=0.000;Z=-6.123, P=0.000;t=-3.152,P=0.002),and the patients whose HCV RNA were negative younger than those who with HCV RNA positive (44.17 vs 55.27 years).Conclusion It is easy for autoimmunity to occur on persons infected HCV.The posi-tive rate of autoantibody is related to patients’age,but not to the HCV amount in patients.Besides,it cannot predict the sta-tus of the patients’liver injury that weather the autoimmunity appears.But HCV load correlated with patients'age and liver inj ury,which older group patients bring higher virus load and had more serious liver damage.

Oncogene DEK shows synergestic effect with transcriptional factor AP-2α to promote HER2 overexpression in breast cancer / 基础医学与临床

Objective To investigate the pathological significance of DEK-AP-2α interaction in HER2 overexpres-sion and breast tumorigenesis. Methods The protein level of DEK,AP-2α and HER-2 in breast tumor tissues was detected by Western blot. The interaction of DEK and AP-2α in MDA-MB-453 mammary cancer cells was detected by immuno-coprecipitation. Furthermore the impact of DEK and AP-2α on HER2 expression was investigated by siRNA in MDA-MB-453 mammary cancer cells followed by semi-quantitive RT-PCR and Western blot. Results A correlation between DEK, AP-2α and HER2 levels in breast cancer tissues were found. The interaction between DEK and AP-2α in MDA-MB-453 cells was verified by co-immunoprecipitation assay. Depletion of DEK and AP-2α in MDA-MB-453 cell by siRNA cooperatively repressed HER2 expression at both the mRNA and protein levels. Conclusion Oncogene DEK has synergestic effect with AP-2α transcriptional factor to promote HER2 overexpres-sion in breast cancer.