Clinical relevance of autoantibodies targeting peptidylarginine deiminases 2 and 4 in rheumatoid arthritis / 中华检验医学杂志

Objective:To evaluate the clinical performance of anti-peptidylarginine deiminase 2 (PAD2) and anti-PAD4 antibodies combined testing in a Chinese rheumatoid arthritis (RA) cohort.Methods:A total of 148 RA inpatients and 35 patients with non-RA arthritis as controls (DC) were recruited from November, 2018 to November, 2019 in Peking University People′s Hospital. In addition, a total of 44 healthy controls (HC) who went to Peking University People′s Hospital for annual physical examination were collected from June 2019 to July 2019. The α-PAD2 and α-PAD4 level in clinical specimens were determined by ELISA. Statistical analysis was performed by the Mann-Whitney U test, the Kruskal-Wallis (KW) test, the χ 2 test or the Fisher′s Exact Test, as necessary. Correlation analysis were performed by logistic regression. Results:α-PAD2 and α-PAD4 were present in 26.4% (39/148) and 20.9% (31/148) patients with RA, 5.7% (2/35) and 5.7% DC (2/35) and 4.5% (2/44) and 2.3% HC (2/44), respectively. α-PAD4-positive RA patients displayed significantly longer disease duration compared to α-PAD4-negative RA patients (17.3±13.2 years vs 8.6±10.2 years, P<0.001). α-PAD4-positive RA patients showed a significantly higher incidence of interstitial lung disease (ILD) compared to those without α-PAD4 (54.8% vs 25.6%, P=0.002). No associations between α-PAD2 and ILD were found ( OR: 0.797, P=0.579). In contrast, significant associations between α-PAD4 and ILD were found ( OR: 3.521, P=0.002). In seropositive RA, α-PAD4 displayed a weak correlation with ILD ( OR: 2.324, P=0.046), but this association was greatly enhanced when combined with α-PAD2 [anti-PAD2 (-)] ( OR: 4.059, P=0.007). Conclusions:The findings delineate the clinical relevance of α-PAD2 and α-PAD4 in RA and suggest that the combined testing for α-PAD2 and α-PAD4 may provide additional diagnostic value to the current clinically available assays in RA, in particular in identifying patients at risk of RA-ILD.

Values of serum IgG4, IgG4/IgG ratio,and IgG4/IgG1 ratio in the diagnosis of Mikulicz′s disease / 中华检验医学杂志

Objective To evaluate values of Serum IgG 4,IgG4/IgG ratio,and IgG4/IgG1 ratio for distinguishing Mikulicz′s disease(MD)from primary Sj?gren′s syndrome(pSS).Methods It retrospectively analyzed 186 patients subjected to serum IgG subclass testing to differentiate MD from primary Sj?gren′s syndrome(pSS)at Peking University People′s Hospital from July 2012 to July 2016.This sample included 42 MD patients and 144 pSS patients.Serum IgG subclass concentrations were measured using Siemens reagents with nephelometry and BNⅡinstrument.In partial patients,serum antinuclear antibodies (ANA)were detected by indirect immunofluorescence assay, and serum anti-SSA antibodies and anti-SSB antibodies were detected by Western blot.Serum IgG subclass test results,ANA test results,serum anti-SSA antibody,and anti-SSB antibody test results were collected.The quantitative data were represented by median(quantile range).The Mann-Whitney U test was used to compare the medians between the two groups.Categorical variables were analyzed with a χ2test and were shown as percentages.The ROC curve was constructed to identify the optimal cut-off values and the area under the curve(AUC)values of the serum IgG4,IgG4/IgG ratio,and IgG4/IgG1 ratio for distinguishing MD patients from pSS patients.Results The medians of serum IgG4, IgG4/IgG ratio and IgG4/IgG1 ratio in MD patients were 11 200 mg/L(17 330),0.444(0.314)and 1.318(1.920), as compared with 329 mg/L(490),0.016(0.025)and 0.023(0.039)respectively in pSS patients(Z=-9.368, -9.560, and -9.571, respectively, P<0.001).For distinguishing MD from pSS, the optimal cut-off values of serum IgG4, IgG4/IgG ratio, and IgG4/IgG1 ratio were 1 870 mg/L,0.111, and 0.206, respectively.The corresponding AUC values were 0.976,0.985,and 0.986,respectively.Comparison of the ROC curves showed that there was no significant difference between AUC of serum IgG4/IgG ratio and IgG4/IgG1 ratio(Z=0.283, P=0.777).But AUC of serum IgG4/IgG ratio and IgG4/IgG1 ratio were significantly higher than AUC of serum IgG 4(Z=2.360 and 1.975,repectively,P=0.018 and 0.048,respectively).The positive rates of serum ANA in MD and pSS group were 10%and 85.8%,respectively(χ2=71.340,P<0.001).The positive rates of anti-SSA antibody and anti-SSB antibody in MD were 6.7%and 0%,respectively.Compared to 72.3%and 38.3%in pSS group, they were lower(χ2=44.773 and 16.792, P<0.001).Conclusions Measurements of serum IgG4 concentration,IgG4/IgG ratio, and IgG4/IgG1 ratio were of important values in differentiating MD from pSS.Serum IgG4/IgG ratio or IgG4/IgG1 ratio was superior to serum IgG4.

Detection of human cytomegalovirus UL97 gene mutations conferring ganciclovir resistance / 中华检验医学杂志

Objective To explore human cytomegalovirus UL97 mutations related to ganciclovir resistance in hematopoietic stem cell transplant (HSCT) recipients.Methods A total of 43 patients,including 24 males and 19 females,with an average age of 21 years old,who had HCMV DNAemia for more than two weeks after HSCT between 2008 and 2010 in Peking University People's Hospital,were included in this prospective study.UL97 GCV resistance mutations were investigated in 49 plasma specimens collected from those patients.GCV resistance mutations such as UL97 M460V/I,H520Q,A591V,A594V,L595S/F,and C603W,were analyzed by modified PCR-RFLP methods.UL97 mutations related to GCV resistance were assayed by the method of PCR-direct sequencing (PCR-DS).An amplified refractory mutation system real-time PCR (ARMS RT-PCR) was developed for the detection of UL97 A594V mutation.Results Eight known UL97 ganciclovir resistance mutations were not detected by PCR-RFLP and PCR-DS.Four new UL97 mutations like UL97 R494P,T502A,N558D,and G561S,were detected by PCR-DS.The ARMS RT-PCR for detecting of UL97 A594V was established successfully.The lower limit of detection of the method was at least 7.5 × 102 copies/ml combined with the use of nucleic acid extraction reagent.UL97 A594V resistance mutation was identified by the method of ARMS RT-PCR in two HSCT recipients.The rate of UL97 A594V mutation was 4.7％ (2/43) in HSCT recipients.Conclusion The ARMS RT-PCR assay represented a sensitive method for the identification of UL97 A594V mutation.

Study of cellular immunity on anti-mycobacterium tuberculosis after immunization of H37Ra in mice / 第三军医大学学报

Objective To study the location of mycobacterium tuberculosis(MTB) and whether the cellular immunity is induced after immunization of H37Ra in mice.Methods Totally 72 BALB/C mice were included.Thirty mice were intracutaneously injected of 0.1 ml H37Ra solution(about 10~(6) bacteria) at caudal region;thirty mice were injected of BCG of same quantity instead;twelve were free from immunization as control.Viable MTB were detected in spleen and lungs on day 15,30 and 60 after intracutaneous vaccination of H37Ra.The proliferation of T lymphocytes stimulated with purified protein derivative(PPD) was measured by MTT assay and the production of interleukin-2(IL-2) and soluble interleukin-2 receptor(sIL-2R) in the cultural supernatants of T lymphocytes was also determined by ELISA on day 30 and 60 after intracutaneous vaccination of H37Ra.Results Viable H37Ra or BCG could be located in the spleen and lungs in mice for at least 60 d.After H37Ra immunization,the stimulation index(SI) of T lymphocyte proliferation on day 30 and 60 was(2.81?0.63),(2.16?0.52) respectively,which was of no significant difference with that of BCG immunization,but of significant difference with that of non-immunized mice(P

Growth of mycobacterium tuberculosis H37Ra in the organs of mice after immunization / 重庆医科大学学报

0.05).But at sixtieth day after immunization,the number of H37Ra growing in the spleen or lung was significantly larger than those of BCG(P