Correlation between PAFAH1B3 Expression Level and Risk of Disease Progression After Autologous Hematopoietic Stem Cell Transplantation in Multiple Myeloma Patients / 中国实验血液学杂志

OBJECTIVE@#To investigate the association between the expression level of platelet-activating factor acetylhydrolase 1B3 (PAFAH1B3 ) gene in bone marrow CD138+ cells of patients with multiple myeloma (MM) treated with autologous hematopoietic stem cell transplantation (AHSCT) and the prognosis within 2 years.@*METHODS@#147 MM patients treated with AHSCT in The First and The Second Affiliated Hospital of Nantong University from May 2014 to May 2019 were included in the study. Expression level of PAFAH1B3 mRNA in bone marrow CD138+ cells of the patients was detected. Patients with disease progression or death during 2 years of follow-up were included in progression group, and the rest were included in good prognosis group. After comparing the clinical data and PAFAH1B3 mRNA expression levels of the two groups, the patients were divided into high PAFAH1B3 expression group and low PAFAH1B3 expression group based on the median PAFAH1B3 mRNA expression level of the enrolled patients. Progression-free survival rate (PFSR) between the two groups was compared by the Kaplan-Meier method. The related factors of prognosis within 2 years were analyzed by univariate analysis and multivariate COX regression analysis.@*RESULTS@#At the end of follow-up, there were 13 patients lost to follow-up. Finally, 44 patients were included in the progression group and 90 patients were included in the good prognosis group. Age in the progression group was higher than that in the good prognosis group, the proportion of patients with CR+VGPR after transplantation in the progression group was lower than that in the good prognosis group, and there was a statistical difference between two groups in the cases distribution of ISS stage (all P<0.05). PAFAH1B3 mRNA expression level and the proportion of patients with LDH>250U/L in the progression group were higher than those in the good prognosis group, and platelet count in the progression group was lower than that in the good prognosis group (all P<0.05). Compared with the low PAFAH1B3 expression group, the 2-year PFSR of the high PAFAH1B3 expression group was significantly lower (log-rank χ2=8.167, P=0.004). LDH>250U/L (HR=3.389, P=0.010), PAFAH1B3 mRNA expression (HR=50.561, P=0.001) and ISS stage Ⅲ(HR=1.000, P=0.003) were independent risk factors for prognosis in MM patients, and ISS stage Ⅰ (HR=0.133, P=0.001) was independent protective factor.@*CONCLUSION@#The expression level of PAFAH1B3 mRNA in bone marrow CD138+ cells is related to the prognosis of MM patients treated with AHSCT, and detecting PAFAH1B3 mRNA expression can bring some information for predicting PFSR and prognostic stratification of patients.

Study of the platelet activating factor acetylhydrolase activity of a gene product encoded by LA2144 gene of Leptospira interrogans / 中华微生物学和免疫学杂志

Objective To analyze the platelet activating factor acetylhydrolase ( PAF-AH) activity of a gene product encoded by LA2144 gene of Leptospira interrogans ( L. interrogans) , to investigate the ex-pression and secretion of LA2144 protein in various cell cultures and to further understand its function in in-ducing internal hemorrhage in an animal model. Methods The DNA sample containing LA2144 gene was extracted from L. interrogans serogroup Icterohaemorrhagiae serovar Lai strain Lai and used as the template for gene cloning by PCR. The LA2144 gene without the signal sequence coding region was amplified by PCR and inserted into a prokaryotic expression construct for the protein expression. The expressed recombinant protein, rLep-PAF-AH, was purified by Ni-NTA affinity chromatography. Spectrophotometry was used to measure the hydrolytic activity, hydrolytic efficiency, Km and Kcat values of the rLep-PAF-AH protein in hydrolyzing PAF substrate. Real-time fluorescent quantitative RT-PCR ( qRT-PCR) and Western blot assay were performed to measure the expression of LA2144 gene at mRNA and protein levels in human umbilical vein endothelial cells (HUVEC), human monocytes (THP-1) and murine macrophages (J774A. 1) with L. interrogans strain Lai infection, respectively. Each syrian hamster was intravenously injected with 100 μg of LPS-free rLep-PAF-AH for two times. Hemorrhage in the lungs, livers and kidneys were observed in three days after the injection. Results The constructed prokaryotic expression system for LA2144 gene of L. inter-rogans strain Lai could highly express the rLep-PAF-AH upon the induction of IPTG. The purified rLep-PAF-AH showed high purity with a single protein band in gel as indicated by SDS-PAGE. The efficiency of 5 μg of rLep-PAF-AH in hydrolyzing PAF substrate was 26. 6 U/L with a Km value of 82. 79 μmol/L and a Kcat value of 0. 24 S-1 . The expression of Lep-PAF-AH at mRNA level in HUVEC, THP-1 and J774A. 1 cells were significantly elevated after co-culture with L. interrogans strain Lai for 1 or 2 hours (P<0. 05). A large amount of Lep-PAF-AH were detected in the supernatants from co-cultures of L. interrogans strain Lai with the three cell lines, but not from the culture of the spirochete in EMJH medium. The signs of hemor-rhage were observed in the lung of hamsters injected with rLep-PAF-AH, but not in tissue samples from liver and kidney. Conclusion The LA2144 gene product was characterized by a stronger PAF-AH activity. The expression of LA2144 gene at mRNA and protein levels in various cell lines were enhanced during L. interro-gans infection. Moreover, the rLep-PAF-AH could induce the pulmonary hemorrhage in hamsters. This stud-y indicated that the protein encoded by LA2144 gene was an important virulence factor causing hemorrhage in hosts during L. interrogans infection.

A cross-sectional study on the association between platelet-activating factor acetylhydrolase gene polymor-phism and cerebral artery atherosclerotic stenosis / 中国神经精神疾病杂志

Objective To investigate the relationship between platelet-activating factor acetylhydrolase gene Arg92His(4, 275; G→A), Ile198Thr(7, 593; T→C) and Val279Phe(9, 994; G→T) mutation and cerebral artery athero-sclerosis stenosis. Methods Six hundred forty-twopatients with cerebral infarction underwent cerebral digital subtrac-tion angiography (DSA).The patients were then divided into cerebral artery atherosclerosis stenosis (CAAS) group(n=477) and control group(n=81) accroding to the site and severity of their cerebral artery stenosis. Furthermore, the CAAS group were divided into intracranial artery stenosis(ICAS) subgroup(n=251), extracranial artery stenosis(ECAS) subgroup (n=115) and extracranial-intracerebral artery stenosis(ECAS) subgroup(n=111). The distributions of genotype and allele frequencies of Arg92His,Ile198Thr and Val279Phe mutation of platelet-activating factor acetylhydrolase gene were ex-amined and comparied in different groups. Results There were significant differences in the distributions of genotype and allele of Arg92His mutation between ICAS subgroup and control group(42.6% vs. 30.3%;23.3% vs. 16.4%, P 0.05). The distributions of genotype and allele of Arg92His, Ile198Thr and Val279Phe mutation were no significantly difference between CAAS group and control group (P >0.05). Conclusions Arg92His mutation may be associated with intracranial artery atherosclerotic stenosis.

Activity of platelet activating factor acetylhydrolase following phase I periodontal therapy / Actividad de la acetilhidrolasa del factor activador de las plaquetas tras la fase I de la terapia periodontal

OBJECTIVE: Elevated levels of platelet activating factor (PAF), a potent inflammatory mediator, in perio-dontal disease and decreased PAF levels following periodontal surgical therapy have been previously detected in gingival tissues and gingival crevicular fluid (GCF). Platelet activating factor acetylhydrolase (PAF-AH) is a calcium-independent phospholipase A2 that catalyses the hydrolysis of PAF, thereby inactivating this mediator. The hypothesis, a relationship between activity of PAF-AH and healing following periodontal therapy, was tested by detecting activity of PAF-AH in GCF samples collected from sites that had undergone phase I periodontal therapy with generalized chronic periodontitis. METHODS: Twenty patients with generalized chronic periodontitis were divided into two groups (n = 10): group 1 with probing pocket depth (PPD) 4-5 mm and group 2 with PPD > 6-8 mm. Clinical parameters were recorded and GCF was sampled before phase I periodontal therapy and at the 2nd, 7th, 14th, 21st and 28th day follow-up evaluation visits. Activity of PAF-AH in GCF was analysed by enzyme-linked immunosorbent assay (ELISA). RESULTS: Probing pocket depth at the 21st and 28th day in group 1, and PPD at the 14th, 21st and 28th day in group 2 were significantly decreased when compared to the baseline values (p < 0.001). Activity of PAF-AH (µmol/ml) was significantly decreased at the 7th, 14th, 21st and 28th day following phase I periodontal therapy in both groups 1 and 2 compared to the baseline values (p < 0.05). CONCLUSION: Platelet activating factor acetylhydrolase is detectable in GCF by ELISA and showed a continuous decrease following phase I periodontal therapy. Changes in the PAF-AH activity would be a progressive marker of periodontal healing to evaluate the success of periodontal therapies.

OBJETIVO: Niveles elevados del factor activador de las plaquetas (PAF) - un potente mediador inflamatorio en la enfermedad periodontal - y niveles disminuidos de PAF tras la terapia quirúrgica periodontal, han sido detectados previamente en los tejidos gingivales y el fluido crevicular gingival (FCG). La acetilhidrolasa del factor activador de las plaquetas(PAF-AH) es una fosfolipasa A2 independiente del calcio, que cataliza la hidrólisis de PAF, inactivando así este mediador. La hipótesis - la existencia de una relación entre la actividad de PAF-AH y la curación tras la terapia periodontal - fue sometida a comprobación mediante la detección de la actividad de PAF-AH en muestras de FCG recogidas de sitios que pasaron por la fase I de la terapia periodontal por periodontitis crónica generalizada. MÉTODOS: Veinte pacientes con periodontitis crónica generalizada fueron divididos en dos grupos (n = 10): grupo 1 con una profundidad de bolsa al sondeo (PPD) de 4-5 mm, y grupo 2 con PPD = 6-8 mm. Se registraron los parámetros clínicos, y se obtuvieron muestras de FCG antes de la fase I de la terapia periodontal, y en las visitas de evaluación de seguimiento los días 2, 7, 14, 21 y 28. La actividad de PAF-AH en FCG se analizó mediante ensayo por inmunoabsorción ligada a enzimas (ELISA). RESULTADOS: La profundidad de bolsa al sondeo los días 21 y 28 en el grupo 1, y PPD los días 14, 21 y 28 en el grupo 2 se vieron disminuidas significativamente cuando se les comparó con los valores iniciales (p < 0.001). La actividad de PAF-AH (µmol/ml) disminuyó significativamente los días 7, 14, 21 y 28 tras la fase I de la terapia periodontal en ambos grupos 1 y 2 en comparación con los valores al inicio del estudio (p< 0.05). CONCLUSIÓN: La acetilhidrolasa del factor activador de las plaquetases detectable en FCG mediante ELISA, y mostró una disminución continua tras la fase I de la terapia periodontal. Los cambios en la actividad de la PAF-AH sería un marcador progresivo de la curación periodontal para evaluar el éxito de las terapias periodontales.

Association between Aia379Val and Val279Phe gene polymorphism of platelet-activating factor acetylhydrolase susceptibility and prognosis of sepsis / 中华微生物学和免疫学杂志

ObjectiveTo determine the allele frequency and genotypic distribution of plateletactivating factor acetylhydrolase (PAF-AH) gene polymorphism in the patients with sepsis. Methods Ala379Val,Val279Phe site genotypes were determined in patients (n=66) and healthy controls(n=68) by means of restriction fragment length polymorphism analysis of polymerase chain reaction products,DNA sequencing was used to detect the PCR product containing allele gene polymorphism.SPSS13.0 statistical software was use to analyze.Results All the samples by PCR-RFLP analysis of the PAF-AH gene in the Ala379Val site have three kinds of genotypes: in 66 cases of sepsis group there were 1 homozygous Val/Val type,19 heterozygous Val/Ala type,46 homozygous Ala/Ala type.In 68 cases of control group there were 2 Val/Val type,22 Val/Ala type,44 Ala/Ala type.The Ala379Val allele frequency and genotypic distribution in the patients with sepsis was not significantly different from those in the healthy controls.No statistically significant difference was observed between the survival group and the death group ( P＞0.05 ).PAFAH gene of Va1279Phe polymorphism could have three kinds of genotypes.All 66 patients in the sepsis group were the homozygous Val/Val type.Control group 68 cases,only one case was homozygous Phe/Phe type,and the others were homozygous Val/Val type,not found heterozygous Val/Phe type.The Val279Phe genotypic distribution and allele gene frequency in the patients with sepsis was not significantly different from those in the healthy controls; no statistically significant difference was observed no statistically significant difference was observed between the survival group and the death group ( P＞0.05 ).ConclusionNo associations were found between PAF-AH gene Ala379Val and Val279Phe polymorphisms and sepsis susceptibility,prognosis and severity.

Construction, purification and substrate specificity identification of recombinant human platelet-activating factor acetylhydrolase isoformⅠ / 上海交通大学学报（医学版）

Objective To construct and purify the recombinant protein of platelet-activating factor acetylhydrolase (PAF-AH) isoform I , and study the enzyme activity by different substrates. Methods The (3 subunit of PAF-AH isoform I was cloned and expressed in E. coli. Exogenously expressed recombinant protein was purified to SDS-PAGE homogeneity, and its activity was identified by arylesterase detection. Phenylacetate, 1-O-hexadecyl-2-deoxy-2-thioacetyl-sn-glycero-3-phosphocholine ( 2-Thio PAF) and l-myristoy1-2-( 4-nitrophenylsuccinyl) phosphatidylcholine (the latter two were commercial plasma PAF-AH substrates) were used for the substrate identification. The plasma type PAF-AH was served as positive control. Results Recombinant protein of β subunit of PAF-AH isoform I was successfully constructed and expressed in E. coli after purification. Compared with positive control, the recombinant protein could hydrolyze phenylacetate and 2-Thio PAF, but could not hydrolyze l-myristoyl-2-( 4-nitrophenylsuccinyl) phosphatidylcholine. Conclusion Recombinant protein of β subunit of PAF-AH isoform I can be successfully constructed. There are differences in the substrate specification to the two commercial PAF substrates for PAF-AH isoform I and plasma type PAF-AH, which provides a quick method to differentiate PAF-AH isoform I from plasma type PAF-AH.

Construction,purification and substrate specificity identification of recombinant human platelet-activating factor acetylhydrolase isoformⅠ / 上海第二医科大学学报

Objective To construct and purify the recombinant protein of platelet-activating factor acetylhydrolase(PAF-AH) isoformⅠ,and study the enzyme activity by different substrates. Methods The ? subunit of PAF-AH isoformⅠwas cloned and expressed in E.coli.Exogenously expressed recombinant protein was purified to SDS-PAGE homogeneity,and its activity was identified by arylesterase detection.Phenylacetate,l-O-hexadecyl-2-deoxy-2-thioacetyl-sn-glycero-3-phosphocholine(2-Thio PAF) and 1-myristoyl-2-(4-nitrophenylsuccinyl) phosphatidylcholine(the latter two were commercial plasma PAF-AH substrates) were used for the substrate identification.The plasma type PAF-AH was served as positive control. Results Recombinant protein of ? subunit of PAF-AH isoformⅠwas successfully constructed and expressed in E.coli after purification.Compared with positive control,the recombinant protein could hydrolyze phenylacetate and 2-Thio PAF,but could not hydrolyze 1-myristoyl-2-(4-nitrophenylsuccinyl) phosphatidylcholine.Conclusion Recombinant protein of ? subunit of PAF-AH isoformⅠcan be successfully constructed.There are differences in the substrate specification to the two commercial PAF substrates for PAF-AH isoformⅠand plasma type PAF-AH,which provides a quick method to differentiate PAF-AH isoformⅠfrom plasma type PAF-AH.

Correlation of Genetical Point Mutation of Platelet Activating Factor Acetylhydrolase and Primary Nephritic Syndrome / 实用儿科临床杂志

Objective To release the correlation of point mutation of platelet activating factor acetylhydrolase(PAF-AH)gene and primary nephritic syndrome (PNS).Method According to the effect of hormonal therapy,94 children with PNS were divided into three groups:steroid-sensitive nephritic syndrome(SSNS),steroid-resistent nephritic syndrome(SRNS),steroid-dependent nephritic syndrome(SDNS).The point mutation of PAF-AH gene (G994T) were identified by molecular biology technique in children with PNS and 239 healthy children were set as control group.Results No statistics differences were found relating to the genotype and allele frequencies between patients with PNS,SSNS,SRNS and normal controls.But it is confirmed that the genotype and allele frequencies among patients with nephritic type nephritic syndrome (NTNS)was higher than patients with simple type nephritic syndrome(STNS) and normal controls.SDNS was higher than both SSNS and normal controls.The number of relapses during the first year after onset was significantly higher in the patients who were heterozygous for the mutant allele (GT) or homozygotes (TT) than in those of the GG homozygotes.Conclusion Most PNS children with PAF-AH gene mutation occurred at position 994 were NTNS.The risk of relapse during the treatment period was higher in patients with PAF-AH gene mutation occurred at position 994.

Correlation of Platelet-Activating Factor Acetylhydrolas Gene Polymorphism and Bronchial Asthma in Children / 实用儿科临床杂志

0.05).Conclusion PAF-AH-Ala379Val gene mutation is unrelated to bronchial asthma in children.

Correlative study between mutation in plasma platelet-activating factor acetylhydrolase gene mutation(Val279-Phe) and cerebral vascular disease / 临床神经病学杂志

Objective To study the correlation between the mutation in platelet activating factor (PAF) acetylhydrolase gene mutation(Val279 Phe)and cerebral vascular disease (CVD)in Chinese.Methods Genomic DNA was analysed for the mutation allele in 153 patients with cerebral vascular disease and 100 healthy subjects matched for age and sex without CVD by a specific polymerase-chain reaction. Plasma PAF acetylhydrolase activity was determined by the method of Stafforini et al.Results The prevalence of the mutation and the frequency of the mutation allele are significantly higher in patient with CVD than those in control subjects( P

Changes of Immunologic Function,Cellular Factor,Genotype and Activities of Platelet Activating Factor-Acetylhydrolase in Different Stadium of Mycoplasma Pneumoniae Pneumonia of Infant / 实用儿科临床杂志

0.05).Conclusions Immunologic function alteration of MPP of infants is showed mainly that Th1 immunologic response is raised,Th2 immunologic response is abated,the cellular factor are changed horizontally,but the immunology index and cellular factor are recovered quickly.There are no relations between MPP of infant and PHF-AH genotype,but there is a downward trend in activity of PHF-AH in acute stage.

The study on activity of platelet-activating factor acetylhydrolase in asthmatic children / 实用儿科临床杂志

Objective Platelet activating factor(PAF),which has been implicated in the pathophysiology of inflammation in asthma,is degraded and inactivated by PAF acetlhydrolase(PAF AH).To investigate the association of PAF AH activity with genotype in asthmatic children.Methods We studied 57 asthmatic children and 30 normal controls. The plasma PAF AH genotype was detected as representative case with 3 different genotypes (Val/Val,Val/Phe and Phe/Phe) by allele specific polymerase chain reaction(AS PCR).The PAF AH activity in plasam was examined by the changes of substrate assay.Results In severe asthmatic individuals plasma PAF AH activities were lower than those of mild or moderate groups and control group,and plasma PAF AH activition was absent 15.4 %.In another three groups plasma PAF AH activation were absent 2 %-3 %.There was significant difference of plasma PAF AH activity among 3 groups of genotype(Val/Val,Val/Phe and Phe/Phe).In the similar genotype, there was no significant difference of plasma PAF AH activity between the groups of control and asthma.Conclusions There was imbalace of PAF/PAF AH in asthmatic children. In severe asthmatic individuals plasma PAF AH activities were lower than those of mild or moderate groups and control group. PAF AH(Val279Phe) gene mutation was related with plasma PAF AH activity.