Salivary secretory leukocyte protease inhibitor levels in patients with stage 3 grade C periodontitis: a comparative cross-sectional study.

Secretory leukocyte protease inhibitor (SLPI) is an anti-protease that protects mucosal tissue integrity owing to its anti-microbial and immunomodulatory properties. This study aimed to investigate SLPI levels in periodontal diseases, and analyze the potential correlation with clinical periodontal parameters. Whole saliva samples were obtained from healthy (n = 24), gingivitis (n = 24) and patients with stage 3 grade C periodontitis (n = 24). SLPI was measured by ELISA and normalized by total protein. Receiver operating characteristics (ROC) curve was used for estimating the area under the curve (AUC). The normalized SLPI levels were significantly reduced in periodontitis compared with gingivitis (4.84-fold) or health (1.83-fold) and negatively correlated with periodontal parameters. The ROC curves showed a good predictor value of the SLPI for differentiation of periodontitis versus health or gingivitis (AUC ≥ 0.80). This study demonstrates that the levels of SLPI are high in periodontal health, further elevated in gingivitis, but eventually decreased in severe periodontitis beyond the former two states. This observation may have broader implications in the context of inflammatory diseases affecting the oral mucosa, as it shows that the bacterial burden is disturbing the homeostatic balances of anti-microbial and anti-protease factors in the oral cavity.

Reduced Expression of Antimicrobial Protein Secretory Leukoprotease Inhibitor and Clusterin in Chronic Rhinosinusitis with Nasal Polyps.

INTRODUCTION: Antimicrobial peptides and proteins (AMPs) constitute the first line of defense against pathogenic microorganisms in the airway. The association between AMPs and chronic rhinosinusitis with nasal polyps (CRSwNP) requires further investigations. This study is aimed at investigating the expression and regulation of major dysregulated AMPs in the nasal mucosa of CRSwNP. METHODS: The expression of AMPs was analyzed in nasal tissue from patients with eosinophilic (E) CRSwNP and nonECRSwNP and healthy subjects using RNA sequencing. The 10 most abundant AMPs expressed differentially in CRSwNP patients were verified by real-time PCR, and of these, the expression and regulation of secretory leukoprotease inhibitor (SLPI) and clusterin (CLU) were investigated further. RESULTS: The 10 most abundant AMPs expressed differentially in CRSwNP compared to healthy control, regardless of subtypes, included BPIFA1, BPIFB1, BPIFB2, CLU, LTF, LYZ, and SLPI, which were downregulated, and S100A8, S100A9, and HIST1H2BC, which were upregulated. ELISA and immunofluorescence confirmed the decreased expression of SLPI and CLU levels in CRSwNP. SLPI is expressed in both nasal epithelial cells and glandular cells, whereas CLU is mainly expressed in glandular cells. AB/PAS staining further demonstrated that both SLPI and CLU were mainly produced by mucous cells in submucosal glands. Furthermore, the numbers of submucosal glands were significantly decreased in nasal polyp tissue of CRSwNP compared to nasal tissue of controls. SLPI was downregulated by TGF-ß1 and IL-4 in cultured nasal tissues in vitro, while CLU expression was inhibited by TGF-ß1. Glucocorticoid treatment for 2 weeks significantly increased the expression of all downregulated AMPs, but not LYZ. Additionally, budesonide significantly increased the expression of SLPI and CLU in cultured nasal tissues. CONCLUSION: The expression of major antimicrobial proteins is significantly decreased in nasal tissue of CRSwNP. The expression of SLPI and CLU is correlated with the numbers of submucosal glands and regulated by inflammatory cytokines and glucocorticoids.

Secretory leukocyte protease inhibitor and progranulin as possible regulators of cervical remodeling in pregnancy.

Secretory leukocyte protease inhibitor (SLPI) and progranulin (PGRN) are secretory proteins with an anti-inflammatory property. Their involvement in cervical remodeling in pregnant uterus is not yet elucidated. Thus, this study aimed to explore the significance of SLPI and PGRN in the maintenance of pregnancy by investigating the factors associated with their expression levels at the cervix. Concentrations of SLPI and PGRN proteins were measured in cervical mucus samples collected from asymptomatic pregnant women at 24-26 weeks of gestation (n = 166). The concentrations of those molecules were analyzed with clinical parameters related to risk for preterm delivery (PD). In pregnant mice, we evaluated the effect of lipopolysaccharide-induced inflammation and progesterone effect modulation on cervical mRNA expression of SLPI and PGRN. The cervical PGRN level was significantly lower in women with short cervix (<35 mm) and with a history of threatened PD. In women with short cervix, cervical SLPI concentrations were positively correlated with inflammatory cytokines, interleukin-6 (R2 = 0.75) and interleukin-8 (R2 = 0.71). In pregnant mice, cervical mRNA expressions of PGRN and SLPI were increased in response to progesterone supplementation and were suppressed by a progesterone antagonist, mifepristone. Lipopolysaccharide-induced inflammation caused remarkable upregulation in cervical SLPI mRNA level but not in PGRN. Progesterone and local inflammation are the factors controlling expression levels of PGRN and SLPI at the cervix. The observed relationship of PGRN and SLPI levels in the cervical mucus with PD-related clinical parameters supports that those anti-inflammatory molecules possibly play a significant role in appropriate regulation of cervical remodeling.

SLPI in the perfusion solution helps to identify graft quality in kidney transplants.

Aim: It is important to find biomarkers that identify the graft quality in kidney transplantation. Results & methodology: The level of SLPI in the cold preservation solution was used as a marker to predict early kidney graft function after transplantation. Before transplantation, kidneys were washed and SLPI was measured in the discarded solution. A retrospective analysis showed that patients with delayed graft function or rejection episodes in post-trasplant, had higher SLPI concentrations in the perfusion solution than patients without delayed graft function or rejections. Furthermore, SLPI could discriminate between patients with better or worse estimated glomerular filtration rate among low-risk patients (kidney donor profile index <80). Discussion & conclusion: These results suggest that the SLPI concentration in the perfusion solutions could be a predictor of short-term organ function and a complement to the kidney donor profile index score.

Dysregulation in Genital Tract Soluble Immune Mediators in Postmenopausal Women Is Distinct by HIV Status.

A rise in new HIV diagnoses among older adults is characterized by poor prognosis and reduced survival times. Although heterosexual transmission remains the main route of infection in women, little is known regarding immune functions in the genital tract of postmenopausal women, especially those who are HIV positive. Furthermore, effects of hormone replacement therapy (HRT) on the genital tract immune system are unclear. Using the Women's Interagency HIV Study repository, we obtained cervical-vaginal lavage (CVL) samples from premenopausal and postmenopausal HIV-positive and HIV-negative women, some of whom were on HRT. Samples were assayed for interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-α, secretory leukocyte protease inhibitor (SLPI), Elafin, human beta defensin-2 (HBD2), and macrophage inflammatory protein (MIP)-3α using ELISA. Anti-HIV activity in CVL was measured using TZM-bl indicator cells. Among HIV-positive women, the plasma viral load was significantly higher and CD4 count was significantly lower in postmenopausal compared with premenopausal women. Postmenopausal women, irrespective of HIV status, had significantly lower levels of HBD2 compared with premenopausal women. Among the HIV-negative individuals, postmenopausal women had significantly lower levels of MIP-3α, IL-6, and SLPI compared with premenopausal women. In contrast, HIV-positive postmenopausal women had significantly higher levels of TNF-α compared with HIV-positive premenopausal women. In most cases, HRT groups resembled the postmenopausal groups. No significant differences in anti-HIV activity by menopausal or by HIV status were noted. Our findings indicate that the female genital tract immune microenvironment is distinct by menopausal status and HIV status. Further studies are needed to assess the risk of HIV acquisition/transmission in this population.

Cervical Local Immune Response for High-Risk Human Papillomavirus Infection: Involvement With Cervical Mucus SLPI Proteins.

PURPOSE: To evaluate cervical mucus secretory leukocyte protease inhibitor (SLPI) concentrations in patients with high-risk human papillomavirus (hrHPV) 16 or 18 positive and low-grade squamous intraepithelial lesions (LGSIL) or high-grade squamous intraepithelial lesions (HGSIL). METHOD: Patients with HPV 16 or 18 positive from 30 to 45 years of age whose cervical cancer screening results reported cytologically LGSIL or HGSIL were included in the study. In the control group, we included participants in the same age with cytology negative and HPV-negative healthy women. All cytological LGSIL or HGSIL results were histopathologically confirmed with colposcopic biopsy specimens. Finally, the study consisted of a total of 3 groups each containing 25 participants as follows: (1) Pap smear and HPV-negative control group, (2) HPV 16 or HPV 18 and LGSIL-positive participants, and (3) HPV 16 or 18 and HGSIL-positive participants. Cervical mucus SLPI levels were analyzed using the enzyme-linked immunosorbent assay method. RESULTS: The mean cervical mucus SLPI levels were 32.94 ng/mL (range: 23-41.29 ng/mL) in the hrHPV + LGSIL group, 29.40 ng/mL (range: 21.03-38.95 ng/mL) in the hrHPV + HGSIL, and 18.75 ng/mL (range: 13.58-29.24 ng/mL) in the healthy control group. Cervical mucus SLPI levels were found to be significantly higher in the hrHPV + LGSIL and hrHPV + HGSIL groups compared to the control group ( P < .001). CONCLUSIONS: The data from the present study indicate that SLPI seems to be one of the important immunomodulatory proteins that provide local immune response in cervical mucosa.

Neutrophil elastase in cervical fluid in women with short cervical length.

OBJECTIVE: The aim of the study was to determine the relationships between short cervical length (CL) and levels of cervical fluid neutrophil elastase (NE), secretory leukocyte protease inhibitor (SLPI), and interleukin 8 (IL-8) in the second trimester of pregnancy of women who underwent ultrasound-indicated cervical cerclage. MATERIALS AND METHODS: CL of <25 mm or cervical funneling were included in the short CL group (n = 26) and the normal CL group (n = 22) included women who had CL of ≥25 mm and had no cervical funneling in women between 17 + 0 and 24 + 6 weeks of gestation. Levels of NE, SLPI, and IL-8 were measured by using enzyme-linked immunosorbent assay kits. Mann-Whitney U tests and Spearman's correlation analysis were used for statistical analyses. RESULTS: Compared with the normal CL group, the short CL group had significantly higher median NE levels (P < 0.001) and higher, though not significant, median IL-8 levels by approximately three times (2107.0 vs. 798.3 pg/mL, P = 0.132). The median SLPI levels in cervical fluid was similar between the two groups (107.6 vs. 103.2 ng/mL, P = 0.499). Short CL had a significant correlations with cervical fluid NE levels (r = -0.475, P = 0.001). CONCLUSION: Increased cervical fluid NE associated with cervical shortening in second trimester of pregnancy, whereas cervical fluid SLPI had constant levels.

Antimicrobial peptide levels are linked to airway inflammation, bacterial colonisation and exacerbations in chronic obstructive pulmonary disease.

Antimicrobial peptides (AMPs) are effectors of host defence against infection, inflammation and wound repair. We aimed to study AMP levels in stable chronic obstructive pulmonary disease (COPD) and during acute exacerbations of COPD (AECOPD), and to examine their relation to clinical parameters and inflammatory markers.The 3-year Bergen COPD Cohort Study included 433 COPD patients and 325 controls. Induced sputum was obtained and analysed for levels of the AMPs human cathelicidin (hCAP18/LL-37) and secretory leukocyte protease inhibitor (SLPI), and for the inflammatory markers interleukin (IL)-8, IL-6 and tumour necrosis factor-α (TNF-α) using immunoassays. Systemic hCAP18/LL-37 and vitamin D levels were also studied. Treating AMPs as response variables, non-parametric tests were applied for univariate comparison, and linear regression to obtain adjusted estimates. The risk of AECOPD was assessed by Cox proportional-hazard regression.Sputum AMP levels were higher in patients with stable COPD (n=215) compared to controls (n=45), and further changed during AECOPD (n=56), with increased hCAP18/LL-37 and decreased SLPI levels. Plasma hCAP18/LL-37 levels showed a similar pattern. In stable COPD, high sputum hCAP18/LL-37 levels were associated with increased risk of AECOPD, non-typeable Haemophilus influenzae colonisation, higher age, ex-smoking and higher levels of inflammatory markers.Altered levels of selected AMPs are linked to airway inflammation, infection and AECOPD, suggesting a role for these peptides in airway defence mechanisms in COPD.

Distribution and factors associated with salivary secretory leukocyte protease inhibitor concentrations.

OBJECTIVES: This cross-sectional study examined the distribution and correlates of salivary secretory leukocyte protease inhibitor (SLPI) concentrations within a multinational cohort of men. METHODS: Extracellular SLPI was measured in oral gargle cell supernatants of 378 men from three countries using an ELISA-based assay. Risk factor data were collected by a questionnaire. Factors associated with SLPI were assessed using linear and logistic regression for continuous and categorical SLPI, respectively. RESULTS: Among men aged 18-73 years, the median SLPI concentration was 492.0 ng ml-1 (range: 2.3-1919.9). In multivariable modeling, men in Brazil and younger men (18-30 years) were more likely to have higher levels of SLPI [adjusted odds ratio (aOR) 3.84; 95% confidence interval (CI): 1.94-7.59, and aOR 3.84; 95% CI: 1.98-7.43, respectively]. Men with a self-reported sexually transmitted diseases diagnosis in the past 6 months were more likely to have higher SLPI levels (aOR 2.98; 95% CI: 1.1-7.83) and men reporting bleeding/swollen gums were less likely to have higher SLPI (aOR 0.34; 95% CI: 0.15-0.79). Similar results were observed for linear regression models. CONCLUSIONS: Secretory leukocyte protease inhibitor concentrations varied significantly by country and decreased with increasing age. The interaction between SLPI, modifiable factors, and oral infections that influence cancer risk warrants further investigation.

Reduced levels of genital tract immune biomarkers in postmenopausal women: implications for HIV acquisition.

BACKGROUND: Rates of HIV infections are increasing in older adults. Although it is known that the HIV/AIDS epidemics affects women disproportionately, little is known regarding immune functions in the genital tract of postmenopausal women, as relevant to HIV susceptibility. OBJECTIVE: The objective of the study was to compare levels of female reproductive tract immune mediators that are important for HIV-associated immune responses as well as intrinsic anti-HIV activity in the cervical vaginal lavages collected from HIV-negative pre- and postmenopausal women. STUDY DESIGN: Cervical vaginal lavage from 20 premenopausal and 20 postmenopausal women were assayed for interleukin-6, interleukin-8, tumor necrosis factor-α, secretory leukocyte protease inhibitor, elafin, human ß-defensin-2, and macrophage inflammatory protein-3α using standard enzyme-linked immunosorbent assays. Anti-HIV activity of cervical-vaginal lavage was measured using TZM-bl indicator cells against HIV-1 IIIB and BaL. Whereas each postmenopausal woman provided only 1 sample, each premenopausal woman provided 3 samples, during proliferative, ovulatory, and secretory stages, based on menstrual dates. RESULTS: We observed significantly lower levels of tumor necrosis factor-α, MIP-3α, secretory leukocyte protease inhibitor, elafin, and human ß-defensin-2 in cervical vaginal lavage from postmenopausal women compared with premenopausal women. Inhibition of HIV-1 infection was observed for both pre- and postmenopausal women, but cervical vaginal lavage from postmenopausal women showed significantly higher inhibition against HIV-1 BaL after adjusting for total protein concentration, genital pH, and reproductive tract infections. No change in mediators or HIV inhibition was observed through the stages of menstrual cycle. In addition, we observed that postmenopausal women with reproductive tract infections had significantly higher levels of tumor necrosis factor-α and significantly lower levels of interleukin-8, which were not observed in premenopausal women. CONCLUSION: Our findings suggest that female reproductive tract immune microenvironment is distinct in HIV-negative postmenopausal women. Further studies are needed to assess the risk of HIV acquisition/transmission in this population.

Salivary secretory leukocyte protease inhibitor (SLPI) and head and neck cancer: The Cancer Prevention Study II Nutrition Cohort.

OBJECTIVES: Secretory leukocyte protease inhibitor (SLPI) is an innate-immunity protein displaying antimicrobial and anti-inflammatory properties that is found in high concentrations in saliva. The role of extracellular salivary SLPI in head and neck squamous cell carcinoma (HNSCC) remains unclear. Thus, we aimed to evaluate the association between SLPI and HNSCC risk in the Cancer Prevention Study II Nutrition Cohort. MATERIALS AND METHODS: Among 53,180 men and women with no history of cancer who provided an oral rinse between 2001 and 2002, 60 were subsequently diagnosed with incident HNSCC between specimen collection and June 2009. In this nested case-control study, archived oral supernatants were evaluated using the Human SLPI Quantikine ELISA Kit for all 60 cases and 180 controls individually matched on gender, race, date of birth, and date of oral rinse collection. Conditional logistic regression was used to estimate HNSCC risk. RESULTS: Overall, pre-diagnostic salivary SLPI was associated with a non-statistically significant higher risk of HNSCC (OR=1.6, 95% CI=0.9-3.0). Among never smokers, high SLPI was associated with a non-statistically significant lower risk (OR=0.5, 95% CI=0.1-1.9), whereas among ever smokers, high SLPI was associated with a statistically significant higher risk (OR=2.1, 95% CI=1.0-4.3) of HNSCC, compared to low SLPI. CONCLUSION: While results from this study suggest that higher concentrations of salivary SLPI might increase the risk of HNSCC among ever smokers, more research is needed to verify these findings and define the mechanisms by which SLPI and smoking influence the etiology of HNSCC.

Changes of Proteases, Antiproteases, and Pathogens in Cystic Fibrosis Patients' Upper and Lower Airways after IV-Antibiotic Therapy.

BACKGROUND: In cystic fibrosis (CF) the upper (UAW) and lower airways (LAW) are reservoirs for pathogens like Pseudomonas aeruginosa. The consecutive hosts' release of proteolytic enzymes contributes to inflammation and progressive pulmonary destruction. Objectives were to assess dynamics of protease : antiprotease ratios and pathogens in CF-UAW and LAW sampled by nasal lavage (NL) and sputum before and after intravenous- (IV-) antibiotic therapy. METHODS: From 19 IV-antibiotic courses of 17 CF patients NL (10 mL/nostril) and sputum were collected before and after treatment. Microbiological colonization and concentrations of NE/SLPI/CTSS (ELISA) and MMP-9/TIMP-1 (multiplex bead array) were determined. Additionally, changes of sinonasal symptoms were assessed (SNOT-20). RESULTS: IV-antibiotic treatment had more pronounced effects on inflammatory markers in LAW, whereas trends to decrease were also found in UAW. Ratios of MMP-9/TIMP-1 were higher in sputum, and ratios of NE/SLPI were higher in NL. Remarkably, NE/SLPI ratio was 10-fold higher in NL compared to healthy controls. SNOT-20 scores decreased significantly during therapy (P = 0.001). CONCLUSION: For the first time, changes in microbiological patterns in UAW and LAW after IV-antibiotic treatments were assessed, together with changes of protease/antiprotease imbalances. Delayed responses of proteases and antiproteases to IV-antibiotic therapy were found in UAW compared to LAW.

Quantification of secretory leukocyte protease inhibitor (SLPI) in oral gargle specimens collected using mouthwash.

BACKGROUND: Secretory leukocyte protease inhibitor (SLPI) is an innate immunity-associated protein known to inhibit HIV transmission, and is thought to inhibit a variety of infectious agents, including human papillomaviruses (HPVs). We aimed to optimize an established ELISA-based SLPI quantification assay for use with oral gargle specimens collected using mouthwash, and to assess preliminary associations with age, smoking status, and alcohol intake. METHODS: Oral gargle supernatants from 50 individuals were used to optimize the Human SLPI Quantikine ELISA Kit. Sample suitability was assessed and quality control analyses were conducted. RESULTS: Salivary SLPI was successfully recovered from oral gargles with low intra-assay and high inter-individual variability. Initial measurements showed that salivary SLPI varied considerably across individuals, and that SLPI was inversely associated with age. CONCLUSIONS: This optimized assay can be used to examine the role of SLPI in the acquisition of oral HPV and other infections.

Clinical evidence for the role of Trichomonas vaginalis in regulation of secretory leukocyte protease inhibitor in the female genital tract.

BACKGROUND: Secretory leukocyte protease inhibitor (SLPI) is responsible for regulating inflammatory damage to and innate and adaptive immune responses in the vaginal mucosa. Depressed cervicovaginal SLPI levels have been correlated with both Trichomonas vaginalis infection and poor reproductive health outcomes. METHODS: We measured levels of SLPI in 215 vaginal specimens collected from adolescent and young adult females aged 14-22 years. Log-transformed SLPI values were compared by analysis of variance or by an unpaired t test before and after adjustment for confounding effects through the propensity score method. RESULTS: Females receiving hormonal contraceptives and those with an abnormal vaginal pH had lower SLPI levels as compared to their peers. After propensity score adjustment for race, behavioral factors, hormonal use, and other sexually transmitted infections (STIs), SLPI levels were lower in females with a positive T. vaginalis antigen test result, a vaginal pH >4.5, vaginal leukocytosis, and recurrent (vs initial) T. vaginalis infection, with the lowest levels observed in those with the highest T. vaginalis loads. CONCLUSIONS: The SLPI level was reduced by >50% in a T. vaginalis load-dependent manner. Future research should consider whether identifying and treating females with low levels of T. vaginalis infection (before they become wet mount positive) would prevent the loss of SLPI and impaired vaginal immunity. The SLPI level could be used as a vaginal-health marker to evaluate interventions and vaginal products.

Gingival fluid cytokine expression and subgingival bacterial counts during pregnancy and postpartum: a case series.

OBJECTIVES: The aim of this study was to assess gingival fluid (GCF) cytokine messenger RNA (mRNA) levels, subgingival bacteria, and clinical periodontal conditions during a normal pregnancy to postpartum. MATERIALS AND METHODS: Subgingival bacterial samples were analyzed with the checkerboard DNA-DNA hybridization method. GCF samples were assessed with real-time PCR including five proinflammatory cytokines and secretory leukocyte protease inhibitor. RESULTS: Nineteen pregnant women with a mean age of 32 years (S.D. ± 4 years, range 26-42) participated in the study. Full-mouth bleeding scores (BOP) decreased from an average of 41.2% (S.D. ± 18.6%) at the 12th week of pregnancy to 26.6% (S.D. ± 14.4%) at the 4-6 weeks postpartum (p < 0.001). Between week 12 and 4-6 weeks postpartum, the mean probing pocket depth changed from 2.4 mm (S.D. ± 0.4) to 2.3 mm (S.D. ± 0.3) (p = 0.34). Higher counts of Eubacterium saburreum, Parvimonas micra, Selenomonas noxia, and Staphylococcus aureus were found at week 12 of pregnancy than at the 4-6 weeks postpartum examinations (p < 0.001). During and after pregnancy, statistically significant correlations between BOP scores and bacterial counts were observed. BOP scores and GCF levels of selected cytokines were not related to each other and no differences in GCF levels of the cytokines were observed between samples from the 12th week of pregnancy to 4-6 weeks postpartum. Decreasing postpartum counts of Porphyromonas endodontalis and Pseudomonas aeruginosa were associated with decreasing levels of Il-8 and Il-1ß. CONCLUSIONS: BOP decreased after pregnancy without any active periodontal therapy. Associations between bacterial counts and cytokine levels varied greatly in pregnant women with gingivitis and a normal pregnancy outcome. Postpartum associations between GCF cytokines and bacterial counts were more consistent. CLINICAL RELEVANCE: Combined assessments of gingival fluid cytokines and subgingival bacteria may provide important information on host response.

Proteolytic cleavage of elafin by 20S proteasome may contribute to inflammation in acute lung injury.

RATIONALE: We hypothesise that elafin levels in acute lung injury (ALI) decrease over time due, in part, to proteolytic degradation as observed in other lung diseases. OBJECTIVES: The aim of this study was to characterise temporal changes in elafin concentration in patients with ALI and to evaluate whether a decrease in elafin levels is due to elevated protease activity. METHODS: Bronchoalveolar lavage fluid (BALF) was obtained from patients with ALI within 48 h of onset of ALI (day 0), at day 3 and at day 7. Elafin levels were quantified by ELISA. Elafin susceptibility to proteolytic cleavage by ALI BALF was assessed by Western blot and by high-performance liquid chromatography-mass spectrometry. MEASUREMENTS AND MAIN RESULTS: Elafin levels were found to be significantly increased at the onset of ALI compared with healthy volunteers and fell significantly by day 7 compared with day 0. In contrast, levels of secretory leukocyte protease inhibitor did not decrease over time. This decrease in elafin was due to cleavage by the 20S proteasome which was significantly increased in ALI BALF. Incubation of ALI BALF with the proteasome inhibitor epoxomicin confirmed that 20S proteasome protease activity was responsible for proteolytic cleavage of elafin, resulting in diminished anti-elastase activity. In addition, free neutrophil elastase activity significantly increased in ALI BALF from day 0 to day 7. CONCLUSIONS: Elafin concentrations fall within the pulmonary compartment over the course of ALI as a result of proteolytic degradation. This loss of elafin may predispose people, in part, to excessive inflammation in ALI.

Expression of oral secretory leukocyte protease inhibitor in HIV-infected subjects with long-term use of antiretroviral therapy.

BACKGROUND: The objectives of this study were to determine (i) the expression of oral secretory leukocyte protease inhibitor (SLPI) in HIV-infected subjects compared with non-HIV controls, (ii) the oral SLPI expression in HIV-infected subjects with antiretroviral therapy (ART) compared with those without ART, and (iii) factors associated with the expression of oral SLPI. METHODS: Oral tissues and samples of both un-stimulated and stimulated saliva were collected from HIV-infected subjects with and without ART, and non-HIV individuals. The expression of SLPI mRNA in the tissue was determined by quantitative real-time PCR. Salivary SLPI protein was detected using ELISA. Chi-square test and logistic regression analysis were performed to determine the association between HIV/ART status and the expression of oral SLPI. RESULTS: One hundred and fifty-seven HIV-infected subjects were enrolled: 99 on ART (age range, 23-57 years; mean, 39 years), 58 not on ART (age range, 20-59 years; mean, 34 years), and 50 non-HIV controls (age range, 19-59 years; mean, 36 years). The most common ART regimen was 2NRTIs + 1NNRTI. The expression of oral SLPI in stimulated saliva was significantly decreased with HIV infection (P < 0.001). The expression was also significantly different with respect to ART use (P = 0.007). Smoking, CD4(+) cell count, and HIV viral load were the factors associated with the oral SLPI expression. CONCLUSION: The expression of oral SLPI is altered by HIV infection and use of ART. Thus, oral SLPI may be the useful biomarker to identify subjects at risk of infections and malignant transformation due to HIV infection and long-term ART.

Rhinovirus infection induces degradation of antimicrobial peptides and secondary bacterial infection in chronic obstructive pulmonary disease.

RATIONALE: Chronic obstructive pulmonary disease (COPD) exacerbations are associated with virus (mostly rhinovirus) and bacterial infections, but it is not known whether rhinovirus infections precipitate secondary bacterial infections. OBJECTIVES: To investigate relationships between rhinovirus infection and bacterial infection and the role of antimicrobial peptides in COPD exacerbations. METHODS: We infected subjects with moderate COPD and smokers and nonsmokers with normal lung function with rhinovirus. Induced sputum was collected before and repeatedly after rhinovirus infection and virus and bacterial loads measured with quantitative polymerase chain reaction and culture. The antimicrobial peptides secretory leukoprotease inhibitor (SLPI), elafin, pentraxin, LL-37, α-defensins and ß-defensin-2, and the protease neutrophil elastase were measured in sputum supernatants. MEASUREMENTS AND MAIN RESULTS: After rhinovirus infection, secondary bacterial infection was detected in 60% of subjects with COPD, 9.5% of smokers, and 10% of nonsmokers (P < 0.001). Sputum virus load peaked on Days 5-9 and bacterial load on Day 15. Sputum neutrophil elastase was significantly increased and SLPI and elafin significantly reduced after rhinovirus infection exclusively in subjects with COPD with secondary bacterial infections, and SLPI and elafin levels correlated inversely with bacterial load. CONCLUSIONS: Rhinovirus infections are frequently followed by secondary bacterial infections in COPD and cleavage of the antimicrobial peptides SLPI and elafin by virus-induced neutrophil elastase may precipitate these secondary bacterial infections. Therapy targeting neutrophil elastase or enhancing innate immunity may be useful novel therapies for prevention of secondary bacterial infections in virus-induced COPD exacerbations.

Exposure to ozone modulates human airway protease/antiprotease balance contributing to increased influenza A infection.

Exposure to oxidant air pollution is associated with increased respiratory morbidities and susceptibility to infections. Ozone is a commonly encountered oxidant air pollutant, yet its effects on influenza infections in humans are not known. The greater Mexico City area was the primary site for the spring 2009 influenza A H1N1 pandemic, which also coincided with high levels of environmental ozone. Proteolytic cleavage of the viral membrane protein hemagglutinin (HA) is essential for influenza virus infectivity. Recent studies suggest that HA cleavage might be cell-associated and facilitated by the type II transmembrane serine proteases (TTSPs) human airway trypsin-like protease (HAT) and transmembrane protease, serine 2 (TMPRSS2), whose activities are regulated by antiproteases, such as secretory leukocyte protease inhibitor (SLPI). Based on these observations, we sought to determine how acute exposure to ozone may modulate cellular protease/antiprotease expression and function, and to define their roles in a viral infection. We utilized our in vitro model of differentiated human nasal epithelial cells (NECs) to determine the effects of ozone on influenza cleavage, entry, and replication. We show that ozone exposure disrupts the protease/antiprotease balance within the airway liquid. We also determined that functional forms of HAT, TMPRSS2, and SLPI are secreted from human airway epithelium, and acute exposure to ozone inversely alters their expression levels. We also show that addition of antioxidants significantly reduces virus replication through the induction of SLPI. In addition, we determined that ozone-induced cleavage of the viral HA protein is not cell-associated and that secreted endogenous proteases are sufficient to activate HA leading to a significant increase in viral replication. Our data indicate that pre-exposure to ozone disrupts the protease/antiprotease balance found in the human airway, leading to increased influenza susceptibility.

Bacterial and inflammatory behavior of implants in the early healing phase of chronic periodontitis.

OBJECTIVE: To assess the pattern of early bacterial colonization at implants and teeth in patients with a history of chronic periodontitis compared with a group of healthy subjects. Furthermore, the presence of host-derived markers at teeth and implants in the two subject groups was determined. METHOD AND MATERIALS: Subgingival and submucosal plaque and gingival crevicular fluid samples from 37 nonsubmerged healing dental implants and the deepest tooth sites per quadrant were analyzed 2 to 5 months after implant insertion. The presence of periodontal pathogens was assessed by means of real-time polymerase chain reaction. Further, the levels of interleukin (IL)-1Β, IL-8, and IL-10; secretory leukocyte protease inhibitor; and the neutrophil elastase activity were determined. RESULTS: Eleven patients with chronic periodontitis and 13 subjects without periodontitis were recruited for this study. Bacterial species associated with periodontitis were detectable at both the teeth and implants. The presence was always higher in the chronic periodontitis group; the difference was significant for Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans at both the implants and teeth. The levels of IL-1Β were higher at teeth than at implants; in contrast, more IL-10 was measured at the implants. CONCLUSION: The present results indicate that (1) dental implants inserted in periodontally compromised patients are colonized with periodontal pathogens within the first weeks of healing; (2) inflammatory markers (IL-1Β) are present in higher levels at teeth as compared with implants, whereas at implants, anti-inflammatory cytokines (IL-10) might play the important role; and (3) the importance of periodontal treatment prior to implant insertion to reduce bacterial load and inflammation should be emphasized.