Correlation of polymorphism of surfactant protein-B gene in children with idiopathic interstitial lung disease / 中国小儿急救医学

Objective To investigate the distribution of surfactant protein-B(SP-B) gene single nucleotide polymorphisms and to clarify the correlation between SP-B gene polymorphisms and idiopathic interstitial lung disease(ILD) in children.Methods Sixty-seven children with idiopathic ILD(case group) and 102 children without idiopathic ILD(control group)were selected from October 2013 to September 2016 in Shenzhen Children's Hospital and the First Affiliated Hospital of Guangxi Medical University.Total exons and flanking region of SP-B were detected by high-throughput sequencing,genotype and allele distribution of exon 4(T131I)were analyzed.Results SP-B exon 4(T131I) genotypes could check out three genotypes:namely CC,CT and TT.The frequencies of genotype CC,CT and TT of exon 4(T131I) in the case group were 67.16%,25.37%,7.46%,and in the control group were 56.86%,35.29%,7.84%,respectively.There was no significant difference in genotype distribution between the two groups(χ2=1.981,P=0.371).Frequency of allele C was 79.85% in the case group and 74.51% in the control group,no significant difference showed between the two groups(χ2=1.288,P=0.256).In the control group,the mutation frequency of SP-B exon 4(T131I) was 43.14%(44/102),compared to the frequency of mutations in the population data in the thousands of human genome programs was 52.00%,in European was 53.88%,in South Asia was 45.50%,and in American was 41.93%(P>0.05);but the frequency of gene mutations was 26.39% in East Asia and 80.18% in Africa,there were significant differences compared to the control group(P<0.05).Conclusion The genetic polymorphism of SP-B exon 4(T131I)is not correlated with the susceptibility of idiopathic ILD in children.The mutation frequency of SP-B exon 4(T131I)is related to the race and the region.

Déficit congénito de proteína de surfactante: caso clínico / Deficiency of surfactant protein: Case report

Introducción: El déficit congénito de surfactante es una entidad de diagnóstico inhabitual en recién nacidos. Se reporta un caso clínico de déficit de proteína B del surfactante, se revisa el estudio, tratamiento y diagnóstico diferencial de los déficit de proteínas del surfactante y enfermedad crónica intersticial de la infancia. Caso clínico: Recién nacido de término que cursa dificultad respiratoria, con velamiento pulmonar recurrente y respuesta transitoria a administración de surfactante. El estudio inmunohistoquímico y genético confirmaron diagnóstico de déficit de proteína B de surfactante. Conclusiones: La enfermedad pulmonar congénita requiere un alto índice de sospecha. El déficit de proteína B de surfactante genera un cuadro clínico progresivo y mortal en la mayoría de los casos, al igual que el déficit de transportador ATP binding cassette, sub-family A member 3 (ABCA3). El déficit de proteína C es insidioso y puede presentarse con un patrón radiológico pulmonar intersticial. Debido a la similitud en el patrón histológico, el estudio genético permite una mayor certeza en el pronóstico y la posibilidad de entregar un adecuado consejo genético.

Introduction: Congenital surfactant deficiency is a condition infrequently diagnosed in newborns. A clinical case is presented of surfactant protein B deficiency. A review is performed on the study, treatment and differential diagnosis of surfactant protein deficiencies and infant chronic interstitial lung disease. Case report: The case is presented of a term newborn that developed respiratory distress, recurrent pulmonary opacification, and a transient response to the administration of surfactant. Immunohistochemical and genetic studies confirmed the diagnosis of surfactant protein B deficiency. Conclusions: Pulmonary congenital anomalies require a high index of suspicion. Surfactant protein B deficiency is clinically progressive and fatal in the majority of the cases, similar to that of ATP binding cassette subfamily A member 3 (ABCA3) deficiency. Protein C deficiency is insidious and may present with a radiological pulmonary interstitial pattern. Due to the similarity in the histological pattern, genetic studies help to achieve greater certainty in the prognosis and the possibility of providing adequate genetic counselling.

The correlation between neonatal respiratory distress syndrome and Surfactant protein B genetic polymorphisms in the Mongol nationality from Inner Mongolia / 中华急诊医学杂志

Objective To study the association between the SP-B gene 1580 position polymorphisms and neonatal respiratory distress syndrome (NRDS) in the Mongol nationality from Inner Mongolia.To observe the frequency distribution of polymorphisms of SP-B gene 1580 position in the Mongol nationality newborns from Inner Mongolia.Methods The genotypes of SP-B gene 1580 position were detected by using polymerase chain reaction-restriction fragmnent length polymorphism assay and gene sequencing in 323 Mongol nationality newborns including the case group and the control group.The SP-B 1580C/T allele frequencies of the Mongol nationality newborns were compared with those of Han nationality from Wuhan city,German Caucasian,American Caucasian and Japanese.Results In the case group,the frequencies of TT,TC,CC at SP-B gene 1580 position were 19.9％,37.1％ and 43.0％,respectively;the frequency of the T allele was 38.4％ and C allele was 61.6％.In the control group,the frequencies of TT,TC,CC at SP-B gene 1580 position were 25.2％,39.7％ and 35.1％,respectively;the frequency of the T allele was 47.0％ and C allele was 53.0％.There were no significant differences between the case group and the control group (x2 =2.299,P =0.317).The allele frequencies of SP-B 1580 of the Mongol nationality newborns were significantly different from those of German-Caucasian and American-Caucasian (P ＜ 0.05),but were similar to those of Han nationality from Wuhan city and Japanese (P ＞ 0.05).Conclusions SP-B 1580C/T gene polymorphism in the Mongol nationality newborns displays no significant correlation with sex,birth weight or gestational age.There is no obvious correlation between SP-B gene 1580 position polymorphisms,allele frequency and the Mongol nationality NRDS.There is heterogeneity in the frequencies of polymorphisms of SP-B 1580 among different ethnic genes.

Influence of cyclooxygenase-2 inhibitor on the expressions of surfactant protein B and transforming growth factor β1 of newborn rats in hyperoxia environment / 中华实用儿科临床杂志

Objective To investigate the effects of selective cyclooxygease-2 inhibitor on pulmonary surfactant protein(SP-B) and transforming growth factor(TGF-β1) of hyperoxic lung injury in newborn rats.Methods One hundred and five SD rats were randomly divided into 3 groups (35 cases in each group):air group (group Ⅰ),in which the rats were exposed to room air;hyperoxia group(group Ⅱ),in which the rats were exposed to hyperoxia(850 mL/L oxy gen);Celecoxib group(group Ⅲ),in which the rats were exposed to heyperoxia(850 mL/L oxygen) and intraperitoneally injected with 5 mg/kg Celecoxib.The lungs of rats were removed on 3 d,7 d,14 d after birth and the following indices were measured:lung section from the lower right lung were stained with HE,and the histological changes was examined;the contents of SP-B and TGF-β1 in the bronchoalveolar lavage fluid of left lung was determinated by using enzyme-linked immunosorbent assay (ELISA);right upper lung was immunohistochemically stained to measure the contents of SP-B and TGF-β1,quantitative real-time PCR(RT-PCR) was used to detect the mRNA expression of SP-B and TGF-β1.Results There were no inflammatory cells and exudation in the lung in group Ⅰ;in group Ⅱ,the structure disorder,pulmonary edema,and inflammatory infiltrates were found;but the damage was obviously alleviated in group Ⅲ.Protein expression could be better detected by ELISA,at the time of 14 day,SP-B was expressed at different levels in3 groups:(29.93±6.40) ng/L in group Ⅰ,(18.20 ±3.70) ng/L in group Ⅱ and (19.63 ±10.20) ng/L in group Ⅲ,SP-B level in group Ⅱ was significantly lower than that in group Ⅰ (t =13.152,P ＜ 0.01),and the expres sion in group Ⅲ was significantly higher than that in group Ⅱ (t =5.190,P ＜ 0.01).TGF-β1 was expressed at different levels in 3 groups:(34.73 ±2.30) μg/L in group Ⅰ,(41.66 ± 1.80) μg/L in group Ⅱ and (38.03 ±0.20) μg/L in group Ⅲ,and the level of TGF-β1 was significantly higher in group Ⅱ than that in group Ⅰ (t =6.584,P ＜ 0.01),but the expression of group Ⅲ was significantly lower than that in group Ⅱ (t =5.609,P ＜ 0.01).The expression of mRNA was detected by RT-PCR,and at the time of 14 day,SP-B mRNA was expressed at different levels in 3 groups:3.14 ±0.10 in group Ⅰ,0.81 ±0.06 in group Ⅱ and 1.12 ±0.06 in group Ⅲ,and SP-B level in group Ⅱ was significantly lower than that in the group Ⅰ (t =55.050,P ＜0.01),and the expression in group Ⅲ was significantly higher than that in group Ⅱ (t =10.305,P ＜ 0.01).TGF-β1 mRNA was expressed at different levels in the 3 groups:1.94 ±0.03 in group Ⅰ,13.26 ±0.43 in group Ⅱ and 6.49 ±0.26 in group Ⅲ,the level of TGF-β1 was significantly higher in group Ⅱ than that in group Ⅰ (t =75.471,P ＜ 0.01),while the expression of group Ⅲ was significantly lower than that in group Ⅱ (t =38.470,P ＜ 0.01).Conclusions Cyclooxygenase-2 inhibitor can attenuate hyperoxic lung injury in rats,and the mechanism might be related to the reduction of prostaglandin.

Analysis of pulmonary surfactant protein B exons sequencing in 80 very low birth weight prematures / 中华实用儿科临床杂志

Objective To study the relationship between exon gene polymorphism of pulmonary surfactant pro-tein B(SP -B)and the susceptibility and severity,prognosis of respiratory distress syndrome (RDS).Methods To detect the gene sequence of SP -B exon by adopting the gene sequencing technology,and samples were 80 prematures of very low birth weight in Southern Han Chinese,who were divided into 2 groups,the RDS and the non RDS,and the difference of genotype in SP -B exon in 2 groups was compared.Results There was no significant difference between 2 pretem groups in the aspects of the gestational age,sex,birth weight and delivery mode etc(all P >0.05).Fifty -nine prematures of very low birth weight had exons heterogenesis,and there were 2 types of mutations,V1 :Exon2:c.[5A >C]+[5A >C]or c.[5A >C]+[=];V2:Exon5:c.[428C >T]+[428C >T]or c.[428C >T]+[=].There were 20 cases of type V1 ,1 8 cases of type V2,3 cases of type V1 +V2 in 45 cases of RDS,and there were 1 2 cases of type V1 ,9 cases of type V2,no case of type V1 +V2 in the non RDS group.Comparing the incidence of V1 and V2 in 2 groups,there were all significant differences(χ2 =3.73,5.02;all P 0.05).Conclusion Gene polymorphism of SP -B exon are risk factors for premature of very low birth weight in southern Han Chinese in RDS.

Correlation of pulmonary surfactant protein B, C and neonatal respiratory distress syndrome / 国际儿科学杂志

Neonatal respiratory distress syndrome is one of the common critically ill newborn's disease, the pathogenesis of which is closely related to gene mutation of the pulmonary suffactant protein(SP).Surfactant protein is an important component of the pulmonary surfactant, which plays an important role in the structure, metabolism, and function of pulmonary surfactant.SP-B and SP-C in pulmonary surfactant is extremely important and closely related to each other.Study on relationship between the SP gene allelic variation and neonatal respiratory distress syndrome could contribute to early genetic intervention, promote the clinical diagnosis and treatment, and bring far-reaching significance to reduce the neonatal mortality rate.

Significance of genetic variants in intron 4 of the surfactant protein B gene of preterm infants with neonatal respiratory distress syndrome / 中华实用儿科临床杂志

Objective To explore the association between genetic variants in intron 4 of the surfactant protein B(SP-B) gene and neonatal respiratory distress syndrome(NRDS) in preterm infants.Methods Using 1 ∶ 1 casc-control study method,a cohort of 52 preterm infants with NRDS and 52 preterm infants without NRDS(non-NRDS) were recruited.Within 1 week after the patients hospitalized,2 mL venous blood was collected.Genomic DNA was extracted and polymerase chain reaction(PCR) was performed to amplify the special region with conserved sequence motifs and intermotif dinucleotide repeats(CA) n in intron 4 of SP-B gene.PCR products was demonstrated by agarose gel electrophoresis and variants were identified by product size.Results A 550 bp target band could be seen in all PCR products (including NRDS group and non-NRDS group).Besides,an additional band(about 650 bp) could be seen in 3 cases of NRDS and 1 case of non-NRDS,which represented insertion variation.The variation incidence of intron 4 of SP-B gene in NRDS group and non-NRDS group were 5.77％ and 1.92％,respectively,there was significant differences (x2 =44.18,P ＜ 0.05).Conclusion Genetic variants in intron 4 of SP-B gene may contribute to risk of preterm infants with NRDS.

Association between surfactant protein B gene polymorphisms and susceptibility to bronchopulmonary dysplasia in preterm infant / 中华实用儿科临床杂志

Objective To investigate the distribution of surfactant protein B (SP-B) gene single nucleotide polymorphisms and to study the association between the SP-B gene polymorphisms and bronchopulmonary dysplasia (BPD) in preterm infant.Methods Forty-two preterm infants with BPD and 68 preterm infants without BPD (control group) were selected.Polymerase chain reaction with restriction fragment length polymorphism was used to establish the genotype and allele frequencies of the SP-B-18A/C,SP-B 1580C/T,SP-B 8714G/C single nucleotide the polymorphisms,and then the association between the polymorphisms and BPD was analyzed.Results The frequencies of genotype CC,AC,AA of SP-B-18A/C in BPD group and control group were 35.7％,52.4％,11.9％ and 32.3％,47.7％,20.0％,respectively.The frequencies of genotype CC,GC,GG of SP-B 8714G/C in BPD group and the control group were 26.2％,54.8％,19.0％ and 27.7％,58.5％,13.8％,respectively.The frequencies of genotype CC,CT,TT of SP-B 1580C/T in BPD group and control group were 66.7 ％,26.2％,7.1％ and 40.0％,47.7 ％,12.3 ％,respectively.The frequencies of allele C and allele A of SP-B-18A/C in BPD group and control group were 61.9％,38.1％ and 56.2％,43.8％,respectively.The frequencies of allele G and allele C of SP-B 8714G/C in BPD group and control group were 53.6％,46.8％ and 56.9％,43.1％,respectively.The frequencies of allele C and allele T of SP-B 1580C/T in BPD group and control group were 79.8％,20.2％ and 63.8％,36.2％,respectively.SP-B-18A/C,SP-B 1580C/T,SP-B 8714G/C were found to be polymorphic.The frequencies of genotype CC of SP-B 1580C/T in BPD group were significantly higher than those in the controls (x2 =7.26,P ＜ 0.05).The frequencies of allele C of SP-B 1580C/T were also statistically different between BPD group and control group(x2 =6.17,P ＜0.05).The C allele increased the risk of BPD(OR =2.23,95％ CI:1.18-4.24).There was no significant difference between the 2 groups in the frequencies of genotype and allele of SP-B-18A/C and SP-B 8714G/C.Conclusions SP-B 1580C/T polymorphism has association with the etiology of BPD and may serve as the susceptibility gene for BPD,the C allele increase the risk of BPD.SP-B-18A/C and SP-B 8714G/C do not have association with the etiology of BPD.

Decreased Expression of Surfactant Protein Genes Is Associated with an Increased Expression of Forkhead Box M1 Gene in the Fetal Lung Tissues of Premature Rabbits

PURPOSE: Recently, Forkhead box M1 (FoxM1) was reported to be correlated with lung maturation and expression of surfactant proteins (SPs) in mice models. However, no study has been conducted in rabbit lungs despite their high homology with human lungs. Thus, we attempted to investigate serial changes in the expressions of FoxM1 and SP-A/B throughout lung maturation in rabbit fetuses. MATERIALS AND METHODS: Pregnant New Zealand White rabbits were grouped according to gestational age from 5 days before to 2 days after the day of expected full term delivery (F5, F4, F3, F2, F1, F0, P1, and P2). A total of 64 fetuses were enrolled after Cesarean sections. The expressions of mRNA and proteins of FoxM1 and SP-A/B in fetal lung tissue were tested by quantitative reverse-transcriptase real-time PCR and Western blot. Furthermore, their correlations were analyzed. RESULTS: The mRNA expression of SP-A/B showed an increasing tendency positively correlated with gestational age, while the expression of FoxM1 mRNA and protein decreased from F5 to F0. A significant negative correlation was found between the expression levels of FoxM1 and SP-A/B (SP-A: R=-0.517, p=0.001; SP-B: R=-0.615, p<0.001). CONCLUSION: Preterm rabbits demonstrated high expression of FoxM1 mRNA and protein in the lungs compared to full term rabbits. Also, the expression of SP-A/B was inversely related with serial changes in FoxM1 expression. This is the first report to suggest an association between FoxM1 and expression of SP-A/B and lung maturation in preterm rabbits.

Surfactant protein B gene polymorphism in preterm babies with respiratory distress syndrome

The etiology of respiratory distress syndrome (RDS) is multifactorial and multigenic. Studies have suggested that polymorphisms and mutations in the surfactant protein B (SP-B) gene are associated with the pathogenesis of RDS. The objectives of this study were to determine and compare the frequencies of SP-B gene polymorphisms in preterm babies with and without RDS. We studied 151 neonates: 79 preterm babies without RDS and 72 preterm newborns with RDS. The following four SP-B gene polymorphisms were analyzed: A/C at -18, C/T at 1580, A/G at 9306, and G/C at nucleotide 8714. The polymorphisms were detected by PCR amplification of genomic DNA and genotyping. The genotypes were determined using PCR-based converted restriction fragment length polymorphisms. The control group consisted of 42 (53 percent) girls and 37 (47 percent) boys. Weight ranged from 1170 to 3260 g and mean gestational age (GA) was 33.9 weeks (range: 29 to 35 weeks and 6 days). The RDS group consisted of 31 (43 percent) girls and 41 (57 percent) boys. Weight ranged from 614 to 2410 g and mean GA was 32 weeks (range: 26 to 35 weeks). The logistic regression model showed that GA was the variable that most contributed to the occurrence of RDS. The AG genotype of the A/G polymorphism at position 9306 of the SP-B gene was a protective factor in this population (OR = 0.1681; 95 percentCI = 0.0426-0.6629). We did not detect differences in the frequencies of the other polymorphisms between the two groups of newborns.

Pulmonary alveolar proteinosis.

Pulmonary alveolar proteinosis is a rare cause of respiratory distress in neonates. We present a 4-month-old infant who presented with progressive respiratory distress since birth and failure to thrive. He was initially treated as a case of diffuse alveolar disease but on open lung biopsy was diagnosed as pulmonary alveolar proteinosis. The child expired at 7 months of age.

Influence of Vascular Endothelial Growth Factor on Expression of Pulmonary Surfactant Protein B in Premature Rats / 实用儿科临床杂志

Objective To study the influence of vascular endothelial growth factor(VEGF) on development of alveolar epithelial cell Ⅱ (AECⅡ) and expression of pulmonary surfactant protein B(SP-B) in premature rats.Methods Wistar rats at 19 days gestation were paunched to get embryo and primary AECⅡculture.The rats were divided into 4 groups ,VEGF-165 group,Dexamethasone group,VEGF and Dexamethason group,control group. AECⅡ and SP-B expression were measured by immunology histochemistry.Results SP-B had positive expression in VEGF group, Dexamethason group, VEGF and Dexamethason group. SP-B had negative expression in control group.Conclusion VEGF-165 can increase SP-B positive expression and secret of AECⅡ.VEGF promotes lung maturity.

Effect of Dexamethasone on Gene Expression of Surfactant Protein B and Surfactant Protein C / 결핵

BACKGROUND: Surfactant protein B(SP-B) and surfactant protein C(SP-C) are important in accelerating surface spreading of surfactant phospholipid. The glucocorticoids accelerate the morphologic differentiation of epithelial cells into type II cells and increase the rate of phosphatidylcholine synthesis. The hydrophobic surfactant protein has been shown to be upregulated by glucocorticoids in vitro, however, its regulation in vivo is not well established. METHODS: The authors investigated the effects of glucocorticoid on the accumulation of mRNA encoding SP-B and SP-C protein content of the lung. Adult rats were given different doses of subcutaneous dexamethasone and sacrificed at 24 hours and 1 week. SP-B and SP-C mRNA were measured by a filter hybridization method. RESULTS: 1) The accumulation of SP-B mRNA at 24 hours after 0.2 mg/kg dexamethasone treatment was increased by 23.7%. 2) The accumulation of SP-B mRNA at 1 week after 2 mg/kg dexamethasone treatment was significantly increased by 96.6%(P<0.001). 3) The accumulation of SP-C mRNA at 24 hours after 0.2 mg/kg dexamethasone treatment was significantly increased by 42.7%(P<0.01). 4) The accumulation of SP-C mRNA at 1 week after 2 mg/kg dexamethasone treatment was significantly increased by 60.0% (P<0.01). CONCLUSION: The authors concluded that dexamethasone treatment in vivo resulted in increased levels of SP-B mRNA and SP-C mRNA. These results suggested that dexamethasone stimulates the synthesis of hydrophobic proteins associated with surfactant.