PURPOSE: Collectin family is an important component of innate immunity, of which surfactant protein (SP)-D and mannose-binding lectin (MBL) are the most characterized. We examined SP-D and MBL in young children with acute respiratory syncytial virus (RSV) bronchiolitis. METHODS: Sixty-three children (< or =24 months of age) admitted with the first RSV bronchiolitis during 2 epidemics and followed for 1 year after discharge were enrolled. The patients were defined as severe group when they had 2 of followings during admission: hypoxemia (<92% oxygen saturation), rapid breathing (and/or lower chest wall indrawing), and >7 days of hospital stay. All children were evaluated if they had recurrent wheezing during follow-up. SP-D and MBL were measured using enzyme-linked immunosorbent assay in serum collected on admission and compared with controls. Their levels were evaluated in relation to the symptom severity during admission and recurrence of wheezing after discharge. RESULTS: Serum SP-D increased significantly in the patients (P<0.01), but MBL showed no difference compared to the controls. SP-D levels were significantly higher in severe group compared with nonsevere group (P<0.05). SP-D levels in the patients with recurrent wheezing after discharge were significantly higher than in those without (P<0.05). MBL showed no difference in relation to the symptom severity or recurrence of wheezing. CONCLUSION: Our study showed that serum SP-D was associated with the severity of RSV bronchiolitis and suggests that it might be a biomarker of lung injury and recurrence of wheezing illnesses in the young children admitted with their first RSV bronchiolitis.
Anoxia ; Bronchiolitis ; Child ; Collectins ; Enzyme-Linked Immunosorbent Assay ; Follow-Up Studies ; Humans ; Immunity, Innate ; Infant ; Length of Stay ; Lung Injury ; Mannose-Binding Lectin ; Oxygen ; Pulmonary Surfactant-Associated Protein D ; Recurrence ; Respiration ; Respiratory Sounds ; Respiratory Syncytial Viruses ; Thoracic Wall

BACKGROUND AND OBJECTIVES: Collectins (surfactant protein A and D) are proteins with collagen tails and globular lectin domains that appear to play an important role in the first line of host defense in mammalians. However, it is not known if collectins are also present in human nasal mucosa. The purpose of this study was to investigate the expression of collectin proteins in human nasal mucosa and to compare the expressions of SP-A and D mRNA in the normal nasal mucosa and in chronic inflammatory nasal diseases. MATERIALS AND METHOD: Ten chronic rhinosinusitis patients were recruited and ten normal nasal mucosae were used as normal controls. Reverse transcriptase-polymerase chain reaction was performed to detect SP-A and SP-D mRNA. The level of collectin and GAPDH (glyceraldehyde-3-phosphate dehydrogenase) transcripts were semi-quantified with the desitometry. We have characterized the cellular localization of SP-A and SP-D protein using immunohistochemistry. RESULTS: SP-A2/GAPDH mRNA ratio in chronic rhinitis nasal mucosa is greater compared with that in normal nasal mucosa (p<0.05). SP-A protein was expressed in the nasal epithelium and in the epithelial cells of the submucosal glands. SP-D mRNA and protein were not expressed in the nasal mucosa. CONCLUSION: These data provide the first evidence of the presence of collectins in the human nasal mucosa. These results suggested that up-regulation of collectin in chronic rhinosinusitis may be a protective response for the nasal mucosa.
Collagen ; Collectins* ; Epithelial Cells ; Humans* ; Immunohistochemistry ; Nasal Mucosa* ; Nose Diseases ; Pulmonary Surfactant-Associated Protein A ; Pulmonary Surfactant-Associated Protein D ; Pulmonary Surfactants ; Rhinitis ; RNA, Messenger ; Sinusitis ; Staphylococcal Protein A ; Up-Regulation

BACKGROUND AND OBJECTIVES: Surfactant protein-A (SP-A) is a member of the collectin family, and plays an important role in the first-line airway defense. The purpose of study was to examine the expression of SP-A mRNA and protein in human salivary glands, and to investigate its up-regulation during inflammatory conditions of salivary glands. MATERIALS AND METHOD: Reverse transcription-polymerase chain reaction was performed on salivary gland tissues from ten patients with chronic sialadenitis and ten samples of normal salivary gland tissue. The expression levels of SP-A to GAPDH (glyceraldehyde-3-phosphate dehydrogenase) transcripts were semi-quantified by densitometry. We also characterized the cellular localizations of SP-A protein immunohistochemically. RESULTS: SP-A mRNA and protein were detected in normal and chronic sialadenitis glands. The expression levels of SP-A mRNA in salivary glands with chronic sialadenitis was significantly increased as compared with normal salivary glands. Immunohistochemical staining revealed SP-A immunoreactivity in the ductal epithelia of normal salivary glands and chronic sialadenitis, and stronger immunoreactivity was observed in chronic sialadenitis tissues. CONCLUSION: SP-A is present in the human salivary gland epithelium and is up-regulated during chronic sialadenitis. These results suggest that salivary gland SP-A may play an important role in the innate host defense of human salivary glands.
Collectins ; Densitometry ; Epithelium ; Humans ; Pulmonary Surfactant-Associated Protein A ; RNA, Messenger ; Salivary Glands ; Sialadenitis* ; Up-Regulation*

OBJECTIVETo study the variation and clinical significance of serum levels of surfactant proteins A (SP-A) and D (SP-D) among children with different degrees of bronchiolitis.

METHODSSeventy children with bronchiolitis were divided into acute (n=42) and recovery phase groups (n=28). According to the severity of symptoms, the acute phase group was further divided into severe (n=12) and mild subgroups (n=30). Another 26 children who were hospitalized in the same period due to non-infectious diseases and had not undergone surgery were used as the control group. Competitive enzyme-linked immunosorbent assay was performed to measure serum levels of SP-A and SP-D in each group.

RESULTSThe acute phase group had significantly higher serum levels of SP-A and SP-D compared with the recovery phase (P<0.01) and control groups (P<0.01). Compared with the control group, the recovery phase group had elevated levels of SP-A and SP-D (P<0.01). Within the acute phase group, serum levels of SP-A and SP-D in the severe subgroup were significantly higher than in the mild subgroup (P<0.01).

CONCLUSIONSSerum levels of SP-A and SP-D are significantly elevated in children with acute bronchiolitis, and severe cases have higher serum levels of SP-A and SP-D than mild cases. Even after the relief of clinical symptoms, serum levels of SP-A and SP-D remain high. These findings suggest that serum levels of SP-A and SP-D might be useful biomarkers for evaluating the severity of bronchiolitis among children.

Acute Disease ; Biomarkers ; Bronchiolitis ; blood ; Female ; Humans ; Infant ; Male ; Pulmonary Surfactant-Associated Protein A ; blood ; Pulmonary Surfactant-Associated Protein D ; blood ; Severity of Illness Index

The complement system is an innate immune defense machinery comprising components that deploy rapid immune responses and provide efficient protection against foreign invaders and unwanted host elements. The complement system is activated upon recognition of pathogenic microorganisms or altered self-cells by exclusive pattern recognition molecules (PRMs), such as collectins, ficolins and pentraxins. Recent accumulating evidence shows that the different classes of effector PRMs build up a co-operative network and exert synergistic effects on complement activation. In this review, we describe our updated view of the crosstalk between previously unlinked PRMs in complement activation and the potential pathogenic effects during infection and inflammation.
Collectins ; Complement Activation* ; Complement System Proteins* ; Inflammation

OBJECTIVE: Surfactant protein (SP)-A and SP-D are involved in host defense mechanism. The author was prompted to perform a study on morphologic change and SP-A, SP-D level of surfactant after pulmonary injury inflicted by intratracheal bleomycin injection. METHODS: Fifteen white adult rats each weighing 250 g (Sprague-Daw ley) were divided into study (receiving bleomycin, n=9) and control groups (n=6). Study group were given a intratracheal injection of belomycin (5 mg/kg). Two groups were grown for five weeks at twenty five degrees Celsius, after which lung tissue were examined for morphologic change and SP-A and SP-D levels were measured using Western blot assay with densitometer. RESULTS: Before the study, the average weight of the study group was 286.69+/-14.54 g, and control was 286.69+/-14.54 g. Five weeks later, the average weight of the study group was 347.31.31+/-60.53 g and control group 352.71+/-16.84 g. However, no statistical significance was noted. On light microscopy, the control group exhibited normal findings while widening of lung interstitium and fibrotic change coupled with more prominent inflammatory cell infiltration were noted in the study group. The SP-A level were 15.34+/-1.52 ODU/microgram in the study group and 7.70+/-2.81 ODU/microgram in the control. SP-D level were 3.53+/-1.46 ODU/microgram and 7.51+/-2.33 ODU/microgram in the study and control groups respectively, there was a statistical significance (p<0.05). CONCLUSION: The morphologic change after pulmonary fibrosis induced by intratracheal bleomycin injection in white rats can be summarized as chronic inflammatory cell infiltration, fibroblast proliferation, deposition of collagen tissues, and lowering of SP-D level were noted. The increase of SP-A level is subject to further study in the future.
Adult ; Animals ; Bleomycin ; Blotting, Western ; Collagen ; Fibroblasts ; Humans ; Lung ; Lung Injury ; Microscopy ; Pulmonary Fibrosis* ; Pulmonary Surfactant-Associated Protein D ; Rats*

OBJECTIVES: The present study was designed to determine whether there is a relationship between indium compound exposure and interstitial lung damage in workers employed at indium tin oxide manufacturing and reclaiming factories in Korea. METHODS: In 2012, we conducted a study for the prevention of indium induced lung damage in Korea and identified 78 workers who had serum indium or Krebs von den Lungen-6 (KL-6) levels that were higher than the reference values set in Japan (3 microg/L and 500 U/mL, respectively). Thirty-four of the 78 workers underwent chest high-resolution computed tomography (HRCT), and their data were used for statistical analysis. RESULTS: Geometric means (geometric standard deviations) for serum indium, KL-6, and surfactant protein D (SP-D) were 10.9 (6.65) microg/L, 859.0 (1.85) U/mL, and 179.27 (1.81) ng/mL, respectively. HRCT showed intralobular interstitial thickening in 9 workers. A dose-response trend was statistically significant for blood KL-6 levels. All workers who had indium levels > or =50 microg/L had KL-6 levels that exceeded the reference values. However, dose-response trends for blood SP-D levels, KL-6 levels, SP-D levels, and interstitial changes on the HRCT scans were not significantly different. CONCLUSIONS: Our findings suggest that interstitial lung changes could be present in workers with indium exposure. Further studies are required and health risk information regarding indium exposure should be communicated to workers and employers in industries where indium compounds are used to prevent indium induced lung damage in Korea.
Indium* ; Japan ; Korea ; Lung Diseases, Interstitial ; Lung* ; Occupational Exposure ; Pulmonary Surfactant-Associated Protein D ; Reference Values ; Thorax ; Tin

OBJECTIVETo observe the levels of pulmonary surfactant proteins A and D (SP-A, SP-D) in bronchoalveolar lavage fluid (BALF) of children with pneumonia, and to explore their relationships with clinical characteristics.

METHODSThirty-five children with pneumonia were enrolled in this study. Differential cell counts were obtained by Countstar counting board. The levels of SP-A and SP-D in BALF were detected using ELISA.

RESULTSIn children with pneumonia, SP-D levels were significantly higher than SP-A levels (P<0.001). SP-D levels were negatively correlated with the neutrophil percentage in BALF (r(s)=-0.5255, P<0.01). SP-D levels in BALF in children with increased blood C-reactive protein levels (>8 mg/L) were significantly lower than in those with a normal level of C-reactive protein (P<0.05). Compared with those in children without wheezing, SP-D levels in children with wheezing were significantly lower (P<0.01). There was no correlation between SP-A levels and clinical characteristics.

CONCLUSIONSSP-D levels in BALF are significantly higher than SP-A levels, and have a certain correlation with clinical characteristics in children with pneumonia. As a protective factor, SP-D plays a more important role than SP-A in regulating the immune and inflammatory responses.

Bronchoalveolar Lavage Fluid ; chemistry ; C-Reactive Protein ; analysis ; Child ; Child, Preschool ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Infant ; Male ; Pneumonia ; metabolism ; Pulmonary Surfactant-Associated Protein A ; analysis ; Pulmonary Surfactant-Associated Protein D ; analysis

Surfactant proteins A (SP-A) and D (SP-D), both members of the collectin family, play a well established role in apoptotic cell recognition and clearance. Recent in vitro data show that SP-A and SP-D interact with apoptotic neutrophils in a distinct manner. SP-A and SP-D bind in a Ca(2+)-dependent manner to viable and early apoptotic neutrophils whereas the much greater interaction with late apoptotic neutrophils is Ca(2+)-independent. Cell surface molecules on the apoptotic target cells responsible for these interactions had not been identified and this study was done to find candidate target molecules. Myeloperoxidase (MPO), a specific intracellular defense molecule of neutrophils that becomes exposed on the outside of the cell upon apoptosis, was identified by affinity purification, mass-spectrometry and western blotting as a novel binding molecule for SP-A and SP-D. To confirm its role in recognition, it was shown that purified immobilised MPO binds SP-A and SP-D, and that MPO is surface-exposed on late apoptotic neutrophils. SP-A and SP-D inhibit binding of an anti-MPO monoclonal Ab to late apoptotic cells. Fluorescence microscopy confirmed that anti-MPO mAb and SP-A/SP-D colocalise on late apoptotic neutrophils. Desmoplakin was identified as a further potential ligand for SP-A, and neutrophil defensin as a target for both proteins.
Apoptosis ; Binding, Competitive ; Fluorescent Antibody Technique, Indirect ; Humans ; Neutrophils ; chemistry ; cytology ; metabolism ; Peroxidase ; isolation & purification ; metabolism ; Protein Binding ; Pulmonary Surfactant-Associated Protein A ; isolation & purification ; metabolism ; Pulmonary Surfactant-Associated Protein D ; isolation & purification ; metabolism

OBJECTIVETo investigate the dynamic changes in the expression of clara cell protein (CC16) and surfactant protein D (SP-D) in the lung tissues and bronchoalveolar lavage fluid (BALF) of silica-treated rats.

METHODSEighty-four Wistar rats were randomly divided into control group (n = 42) and silica group (n = 42). The silica group was subsequently divided into 3, 7, 14, 21, 28, and 60 d subgroups. The silicotic model was made by instilling silica suspension directly through the trachea into rat lungs. At 3, 7, 14, 21, 28, and 60 d after silica instillation, 8 rats in each group were sacrificed and their lung tissues and BALF were collected. The expression of SP-D and CC16 in lung tissues was detected by immunohistochemistry. Enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of SP-D and CCl6 in BALF.

RESULTSThe immunohistochemical assay indicated that CCl6 and SP-D were expressed in lung cells. The ELISA found that in 7, 14, 21, 28, and 60 d silica subgroups, the content of CCl6 in rat BALF was 8.14±0.70, 7.15±0.66, 7.00±0.69, 6.34 ± 0.59, and 5.27±0.49 ng/L, respectively; CCl6 expression decreased gradually with the silica exposure time prolonged, indicating a negative correlation (ra = -0.953, P < 0.01). Compared with the control group, all silica subgroups had significantly decreased CCl6 levels (P < 0.05). The content of SP-D in BALF was 12.20 ± 1.57, 14.41 ± 0.65, and 12.18 ± 0.74 ng/L, respectively, in the 7, 14, and 21 d silica subgroups, significantly higher than that in the control group (P < 0.05).

CONCLUSIONThe dynamic changes in SP-D and CCl6 protein levels in the lung tissues and BALF of rats could be induced by silica exposure and are related to silica exposure time. With the extension of silica exposure, CCl6 levels are gradually reduced, while the SP-D levels first increase and then fall.

Animals ; Bronchoalveolar Lavage Fluid ; chemistry ; Epithelial Cells ; metabolism ; Lung ; metabolism ; Pulmonary Surfactant-Associated Protein D ; metabolism ; Rats ; Rats, Wistar ; Silicon Dioxide ; toxicity ; Uteroglobin ; metabolism