Bacterial pneumonia causes augmented expression of the secretory leukoprotease inhibitor gene in the murine lung

Immune Memory After Respiratory Infection With Streptococcus pneumoniae Is Revealed by in vitro Stimulation of Murine Splenocytes With Inactivated Pneumococcal Whole Cells: Evidence of Early Recall Responses by Transcriptomic Analysis

The in vitro stimulation of immune system cells with live or killed bacteria is essential for understanding the host response to pathogens. In the present study, we propose a model combining transcriptomic and cytokine assays on murine splenocytes to describe the immune recall in the days following pneumococcal lung infection. Mice were sacrificed at days 1, 2, 4, and 7 after Streptococcus pneumoniae (TIGR4 serotype 4) intranasal infection and splenocytes were cultured in the presence or absence of the same inactivated bacterial strain to access the transcriptomic and cytokine profiles. The stimulation of splenocytes from infected mice led to a higher number of differentially expressed genes than the infection or stimulation alone, resulting in the enrichment of 40 unique blood transcription modules, including many pathways related to adaptive immunity and cytokines. Together with transcriptomic data, cytokines levels suggested the presence of a recall immune response promoting both innate and adaptive immunity, stronger from the fourth day after infection. Dimensionality reduction and feature selection identified key variables of this recall response and the genes associated with the increase in cytokine concentrations. This model could study the immune responses involved in pneumococcal infection and possibly monitor vaccine immune response and experimental therapies efficacy in future studies.

A biomarker panel for risk of early respiratory failure following hematopoietic cell transplantation

This study identified and validated ST2, WFDC2, IL-6, and TNFR1 as risk biomarkers for RF and related mortality post-HCT.

Plasma biomarkers associated with respiratory failure (RF) following hematopoietic cell transplantation (HCT) have not been identified. Therefore, we aimed to validate early (7 and 14 days post-HCT) risk biomarkers for RF. Using tandem mass spectrometry, we compared plasma obtained at day 14 post-HCT from 15 patients with RF and 15 patients without RF. Six candidate proteins, from this discovery cohort or identified in the literature, were measured by enzyme-linked immunosorbent assay in day-7 and day-14 post-HCT samples from the training (n = 213) and validation (n = 119) cohorts. Cox proportional-hazard analyses with biomarkers dichotomized by Youden’s index, as well as landmark analyses to determine the association between biomarkers and RF, were performed. Of the 6 markers, Stimulation-2 (ST2), WAP 4-disulfide core domain protein 2 (WFDC2), interleukin-6 (IL-6), and tumor necrosis factor receptor 1 (TNFR1), measured at day 14 post-HCT, had the most significant association with an increased risk for RF in the training cohort (ST2: hazard ratio [HR], 4.5, P = .004; WFDC2: HR, 4.2, P = .010; IL-6: HR, 6.9, P < .001; and TFNR1: HR, 6.1, P < .001) and in the validation cohort (ST2: HR, 23.2, P = .013; WFDC2: HR, 18.2, P = .019; IL-6: HR, 12.2, P = .014; and TFNR1: HR, 16.1, P = .001) after adjusting for the conditioning regimen. Using cause-specific landmark analyses, including days 7 and 14, high plasma levels of ST2, WFDC2, IL-6, and TNFR1 were associated with an increased HR for RF in the training and validation cohorts. These biomarkers were also predictive of mortality from RF. ST2, WFDC2, IL-6 and TNFR1 levels measured early posttransplantation improve risk stratification for RF and its related mortality.

WFDC Protein: A Promising Diagnosis Biomarker of Ovarian Cancer

An initial diagnosis of cancer is usually based on symptoms, abnormal physical examination and imaging tests. Ovarian cancer is difficult to be diagnosed timely due to the nonspecific symptoms, thus resulting in the high-risk mortality. Despite of the various diagnostic methods, there is still no reliable diagnostic test. Clinically, carbohydrate antigen 125(CA125) is widely recognized as a diagnosis biomarker of ovary cancer. However, CA125 is not sensitive to detect the ovary cancer at the early stage. It is essential to explore other potential biomarkers. Human epididymis protein 4 (HE4) in the whey/four-disulfide core (WFDC) proteins family shows satisfactory sensitivity in the early diagnosis of ovary cancer. In this present review, we summarized the important effects of WFDC family proteins on the proliferation, apoptosis and migration of ovary cancer and intended to provide more evidence to explore the possibility of WFDC protein as a diagnosis biomarker.

Identification of Secretory Leukoprotease Inhibitor As an Endogenous Negative Regulator in Allergic Effector Cells

Mast cells, basophils, and eosinophils are central effectors in allergic inflammatory disorders. These cells secrete abundant serine proteases as well as chemical mediators and cytokines; however, the expression profiles and functions of their endogenous inhibitors remain elusive. We found that murine secretory leukoprotease inhibitor (SLPI) is expressed in basophils and eosinophils but in not in mast cells. SLPI-deficient (Slpi^−/−) basophils produce more cytokines than wild-type mice after IgE stimulation. Although the deletion of SLPI in basophils did not affect the release of chemical mediators upon IgE stimulation, the enzymatic activity of the serine protease tryptase was increased in Slpi^−/− basophils. Mice transferred with Slpi^−/− basophils were highly sensitive to IgE-mediated chronic allergic inflammation. Eosinophils lacking SLPI showed greater interleukin-6 secretion and invasive activity upon lipopolysaccharide stimulation, and the expression of matrix metalloproteinase-9 by these eosinophils was increased without stimulation. The absence of SLPI increases JNK1 phosphorylation at the steady state, and augments the serine phosphorylation of JNK1-downstream ETS transcriptional factor Elk-1 in eosinophils upon stimulation. Of note, SLPI interacts with a scaffold protein, JNK-interacting protein 3 (JIP3), that constitutively binds to the cytoplasmic domain of toll-like receptor (TLR) 4, suggesting that SLPI controls Elk-1 activation via binding to JIP3 in eosinophils. Mice transferred with Slpi^−/− eosinophils showed the exacerbation of chitin-induced allergic inflammation. These findings showed that SLPI is a negative regulator in allergic effector cells and suggested a novel inhibitory role of SLPI in the TLR4 signaling pathways.

Animal models of hospital-acquired pneumonia: current practices and future perspectives

Lower respiratory tract infections are amongst the leading causes of mortality and morbidity worldwide. Especially in hospital settings and more particularly in critically ill ventilated patients, nosocomial pneumonia is one of the most serious infectious complications frequently caused by opportunistic pathogens. Pseudomonas aeruginosa is one of the most important causes of ventilator-associated pneumonia as well as the major cause of chronic pneumonia in cystic fibrosis patients. Animal models of pneumonia allow us to investigate distinct types of pneumonia at various disease stages, studies that are not possible in patients. Different animal models of pneumonia such as one-hit acute pneumonia models, ventilator-associated pneumonia models and biofilm pneumonia models associated with cystic fibrosis have been extensively studied and have considerably aided our understanding of disease pathogenesis and testing and developing new treatment strategies. The present review aims to guide investigators in choosing appropriate animal pneumonia models by describing and comparing the relevant characteristics of each model using P. aeruginosa as a model etiology for hospital-acquired pneumonia. Key to establishing and studying these animal models of infection are well-defined end-points that allow precise monitoring and characterization of disease development that could ultimately aid in translating these findings to patient populations in order to guide therapy. In this respect, and discussed here, is the development of humanized animal models of bacterial pneumonia that could offer unique advantages to study bacterial virulence factor expression and host cytokine production for translational purposes.

Secretory leukocyte protease inhibitor modulates urethane-induced lung carcinogenesis

Secretory leukocyte protease inhibitor (SLPI), 11.7 kDa serine protease inhibitor, is produced primarily in the respiratory tract, but it is often elevated in lung, head/neck and ovarian cancers. SLPI expression in relation to cancer progression, metastasis and invasion has been studied extensively in non-small cell lung cancer. However, the role of SLPI during the early stages of carcinogenesis remains unknown. We hypothesized that SLPI is required from the initiation and promotion to the progression of lung carcinogenesis. A skin allograft model using SLPI-knockout (SLPI-KO) mice and short hairpin RNA-treated cells was used to demonstrate that SLPI expression in tumor cells is crucial for tumor formation. Moreover, lung tumorigenesis induced by urethane, a chemical lung carcinogen, was significantly suppressed in SLPI-KO mice in association with decreased nuclear factor-kappaB (NF-κB) activity. SLPI deficiency also resulted in decreased cell numbers and decreased production of inflammatory cytokines in bronchoalveolar lavage fluids. The suppression of NF-κB activation in SLPI-KO mice was associated with lower expression of NF-κB-related survival genes and DNA repair genes. Our findings demonstrate that SLPI plays an important role from the initial stages of lung carcinogenesis to the progression of lung cancer in an NF-κB-dependent manner.

Antitumor potential of SLPI promoter controlled recombinant caspase-3 expression in laryngeal carcinoma

The purpose of this study is to develop a specific and efficient targeted gene therapy candidate approach for laryngeal carcinomas. Several promoters of human squamous cell carcinoma antigen 2(SCCA2), secretory leukocyte protease inhibitor (SLPI) and Survivin genes were cloned from human genomic DNA and evaluated for tumor-specific transcription potential in human laryngeal carcinoma Hep-2 cells by dual luciferase assays. One SLPI promoter fragment (677 bp) showed the highest efficiency and specificity, and was used to control the expression of a recombinant active caspases-3 (revCasp3), which could trigger apoptosis without activation of its upstream cascade elements once expressed in a cell, in an adenoviral vector (Ad-SLPI-revCasp3), and its antitumor efficacy was assessed. In vitro infection with Ad-SLPI-revCasp3 showed revCasp3 could be specifically expressed in Hep-2 cells, resulting in efficient activation of endogenous Caspase-3 and subsequent apoptosis of Hep-2 cells. In Hep-2 nude mice xenograft model, intratumoral administration of Ad-SLPI-revCasp3 significantly inhibited tumor growth without obvious loss of body weight and obvious hepatic toxicity. In summary, our study showed the specific and efficient apoptosis-inducing potential of Ad-SLPI-revCasp3, and this makes it a new candidate approach of targeted gene therapy for laryngeal squamous cell carcinoma, which needs further systematic investigation.

Innate immune responses of pulmonary epithelial cells to Burkholderia pseudomallei infection

BACKGROUND

Burkholderia pseudomallei, a facultative intracellular pathogen, causes systemic infection in humans with high mortality especially when infection occurs through an infectious aerosol. Previous studies indicated that the epithelial cells in the lung are an active participant in host immunity. In this study, we aimed to investigate the innate immune responses of lung epithelial cells against B. pseudomallei.

METHODOLOGY AND PRINCIPAL FINDINGS

Using a murine lung epithelial cell line, primary lung epithelial cells and an inhalational murine infection model, we characterized the types of innate immunity proteins and peptides produced upon B. pseudomallei infection. Among a wide panel of immune components studied, increased levels of major pro-inflammatory cytokines IL-6 and TNFalpha, chemokine MCP-1, and up-regulation of secretory leukocyte protease inhibitor (SLPI) and chemokine (C-C motif) ligand 20 (CCL20) were observed. Inhibition assays using specific inhibitors suggested that NF-kappaB and p38 MAPK pathways were responsible for these B. pseudomallei-induced antimicrobial peptides.

CONCLUSIONS

Our findings indicate that the respiratory epithelial cells, which form the majority of the cells lining the epithelial tract and the lung, have important roles in the innate immune response against B. pseudomallei infection.

Gene expression signatures characterizing the development of lymphocyte response during experimental Chlamydia pneumoniae infection

In this study experimental mouse model for Chlamydia pneumoniae infection was used to elucidate the nature of immune response developing during primary and secondary infection. First we examined the mononuclear cells from different lymphoid organs in BALB/c mice during C. pneumoniae infection and detected a strong lymphocyte influx into mediastinal lymph nodes (MLN). To further characterize the C. pneumoniae induced immune response the gene expression profiles of MLN derived lymphocytes was studied. To identify genes characteristic for reinfection we compared gene expression profiles during reinfection and primary infection and found 148 genes to be differentially regulated in CD19+ cells, 7 in CD4+ cells and 12 in CD8+ cells. A panel of these genes was selected to be confirmed by real-time RT-PCR. Genes related to interferon signaling like Ifit1, Ifit3, Gbp2, Irf7 and Usp18 were found to be upregulated when reinfection was compared to primary infection. In our study we were able to identify 8 genes that were differentially expressed between reinfection and primary infection in lymphocytes. These novel gene expression signatures provide new insights and clues to the nature of protective immunity established during experimental C. pneumoniae immunity.

Secretory leukocyte peptidase inhibitor and lung cancer

Secretory leukocyte peptidase inhibitor (SLPI) belongs to the whey acidic protein four-disulfide core family of proteins, and has antimicrobial and antiprotease functions. SLPI is produced by the epithelial cells lining the respiratory, digestive, and reproductive tracts. Gene-targeting experiments in mice indicated that one function of SLPI is to protect proepithelin from elastase cleavage in wound healing. In addition to its antiprotease function, SLPI has an anti-inflammatory function through the modulation of nuclear factor-kappaB acting intracellularly, especially in macrophages. SLPI is also produced in cancer tissues, but its role in cancer is not well understood. SLPI genes are often upregulated under tumorigenic conditions. We found a negligible number of tumors in the lungs of SLPI knockout mice 20 or 40 weeks after administration of urethane, an interesting experimental model for investigating the function of SLPI in cancer. This review discusses the normal function of SLPI and its possible roles in cancer tissues.

Current developments in adenovirus-based cancer gene therapy

Adenovirus (Ad)-based cancer gene therapy is a promising, novel approach for treating cancer resistant to established treatment modalities. Unfortunately, the efficacy of nonreplicative first generation Ads was low and data from clinical trials were disappointing. To address this problem, conditionally replicating Ads have been constructed. Infection of tumor cells with conditionally replicating Ads results in tumor-specific replication, subsequent oncolysis and release of the virus progeny. Recently, it has been suggested that the low expression of the coxsackie-Ad receptor is the rate-limiting factor for infectivity with serotype 5 (Ad5). Unfortunately, coxsackie-Ad receptor expression is highly variable and often low on many tumor types. Consequently, molecular strategies have been applied for the development of coxsackie-Ad receptor-independent oncolytic Ads. This review describes recent developments of Ad-based cancer gene therapy, including novel engineering techniques of the Ad capsid for efficient tumor targeting, as well as targeting techniques, to restrict transgene expression to cancer cells.

WFDC2 (HE4): a potential role in the innate immunity of the oral cavity and respiratory tract and the development of adenocarcinomas of the lung

Background

The Whey Acidic Protein domain is an evolutionarily conserved motif found in a number of proteins, the best studied of which are antiproteinases involved in the innate immune defence of multiple epithelia. We recently characterised the WFDC2 gene which encodes a two WAP domain-containing protein, initially suggested as a marker for epididymis, and showed that it is highly expressed in the lung and salivary gland. The precise location of WFDC2 protein in these sites has not been described.

Methods

We used immunohistochemistry to localise WFDC2 in normal tissues of the respiratory tract, naso- and oropharynx, as well as in chronically inflamed lung from Cystic Fibrosis and a range of pulmonary carcinomas. We have complemented these studies with molecular analysis of WFDC2 gene expression in primary human lung cell cultures.

Results

WFDC2 is expressed in some epithelial cells of the upper airways as well as in mucous cells and ducts of submucosal glands. No staining was seen in peripheral lung. Intense staining is found in major salivary glands and in minor glands of the nose, sinuses, posterior tongue and tonsil. Studies with the related protein Secretory Leukocyte Protease Inhibitor (SLPI) show that although both proteins are expressed in similar tissues, the precise cellular localisation differs. Significant increases in expression and localisation of WFDC2 are seen in patients with Cystic Fibrosis. SLPI expression was greatly reduced in the same samples. In cultures of tracheobronchial epithelial cells, expression of WFDC2 and SLPI are differentially regulated during differentiation yet WFDC2 is not induced by pro-inflammatory mediators. The majority of adenocarcinomas stain with WFDC2 whilst a significant minority of squamous, small cell and large cell carcinomas exhibit focal staining. There is no clear association with tumour grade.

Conclusion

We believe that these studies support the hypothesis that WFDC2 may be a component of the innate immune defences of the lung, nasal and oral cavities and suggest that WFDC2 functions in concert with related WAP domain containing proteins in epithelial host defence. We also suggest that WFDC2 re-expression in lung carcinomas may prove to be associated with tumour type and should be studied in further detail.

Protease activity in protein-free NS0 myeloma cell cultures

Zymography of concentrated conditioned medium (CM) from protein-free NS0 myeloma cell cultures showed that this cell line produced and released/secreted several proteases. Two caseinolytic activities at 45-50 and 90 kDa were identified as aspartic acid proteases, and at least two cathepsins of the papain-like cysteine protease family with molecular masses of 30-35 kDa were found by gelatin zymography. One of these cathepsins was identified as cathepsin L by using an enzyme assay exploiting the substrate Z-Phe-Arg-AMC and the inhibitor Z-Phe-Tyr-t(Bu)-DMK. The aspartic acid and cysteine proteases were active only at acidic pH and are therefore not a potential risk for degrading the product or affecting cell growth during culture. Secreted proforms of cathepsins may, however, possess mitogenic functions, but addition of anti-procathepsin L antibodies to NS0 cultures did not influence proliferation. The recombinant antibody product was not degraded in cell-free CM incubated at pH 7, but when the pH was decreased to 3.5-4, the aspartic acid proteases degraded the product. Gelatin zymography also revealed the presence of several serine proteases in NS0 CM, one at 85 kDa and two at 50 kDa, with pH optima close to culture pH. Addition of the serine protease inhibitor aprotinin significantly increased the specific proliferation rate as compared to the control. In addition to these data, N-terminal amino acid sequencing identified two proteins in NS0 CM as the protease inhibitors secretory leukocyte protease inhibitor and cystatin C.

A Fiber-Modified, Secretory Leukoprotease Inhibitor Promoter-Based Conditionally Replicating Adenovirus for Treatment of Ovarian Cancer

Purpose: The use of conditionally replicating adenoviruses (CRAD) is dependent on molecular differences between tumor cells and nontumor cells. Transcriptional targeting of CRAD replication via tumor-specific promoters is an effective way to control replication regulation. Genetic fiber pseudotyping is an approach for circumventing low expression of the primary adenovirus serotype 5 (Ad5) receptor by using the distinct adenovirus serotype 3 (Ad3) receptor for entry into and subsequent killing of ovarian cancer cells.

Experimental Design: In this study, we constructed a fiber-modified CRAD containing the secretory leukoprotease inhibitor (SLPI) promoter to control viral replication via the E1A gene (Ad5/3SLPI). To evaluate the liver toxicity of chimeric 5/3 fiber-modified CRADs, we compared Ad5/3SLPI with Ad5/3Cox-2L, a CRAD with E1A under control of the Cox-2 promoter, and Ad5/3Δ24, a CRAD that replicates in cancer cells inactive in the retinoblastoma/p16 pathway by use of an in vivo hepatotoxicity model and by a model system that uses slices of human liver.

Results: We show efficient viral replication and oncolysis of Ad5/3SLPI in both multiple ovarian cancer cell lines and primary tumor cell spheroids as well as therapeutic efficacy in an orthotopic mouse model of peritoneal carcinomatosis. Ad5/3SLPI showed significantly decreased liver toxicity compared with other 5/3 fiber-modified control vectors examined.

Conclusions: In summary, Ad5/3SLPI is a promising vector candidate for treating metastatic ovarian cancer and showed robust virus replication, oncolysis, and in vivo therapeutic efficacy. Ad5/3SLPI showed comparatively low liver toxicity and therefore holds potential for patient use in the clinic.

Trappin ovine molecule (TOM), the ovine ortholog of elafin, is an acute phase reactant in the lung

As large animal models continue to play an important role in translating lung-directed therapeutic strategies from laboratory animals to humans, there is an increasing interest in the analysis of endogenous regulators of inflammation at both a genomic and a therapeutic level. To this end, we have sought to characterize the ovine ortholog of elafin, an important regulator of inflammation in humans. We have isolated both the elafin cDNA and gene, which have a similar structure to other species' orthologs. Interestingly, we have isolated two alleles for ovine elafin, which contain a very high number of transglutamination repeats, thought to be important in binding elafin to the interstitium. The mainly mucosal mRNA distribution for ovine elafin suggests that ovine elafin may, like its human ortholog, have functions in innate immunity. This is supported by analysis of elafin and the related protein secretory leukocyte protease inhibitor (SLPI) in ovine bronchoalveolar fluid in response to locally administered lipopolysaccharide and confirmation of them acting as "alarm" antiproteases. We have also cloned the ovine elafin cDNA into an adenoviral vector and have demonstrated correct processing of the secreted protein as well as biological activity. Overexpression of ovine elafin in a lung-derived epithelial cell line has a protective effect against the enzymes human neutrophil and porcine pancreatic elastase. The identification of the ovine elafin gene and its translated protein are important in developing practical strategies aimed at regulating inflammation in the large mammalian lung.

Estrogen Induces Expression of Secretory Leukocyte Protease Inhibitor in Rat Uterus1

In rodents, the steroid hormone estrogen (E) profoundly influences the early events in the uterus leading to embryo implantation. It is thought that E triggers the expression of a unique set of genes in the endometrium that in turn control implantation. To identify these E-induced genes, we employed a delayed implantation model system in which embryo attachment to rat endometrium is dependent upon E administration. Using a gene expression screen method, we isolated a number of cDNAs representing mRNAs whose expression is either turned on or turned off in response to an implantation-inducing dose of E. We identified one of these cDNAs as that encoding secretory leukocyte protease inhibitor (SLPI), an inhibitor of serine proteases. The expression of SLPI mRNA was induced in the uteri of ovariectomized rats in response to E, confirming the hormonal regulation of this molecule. Spatiotemporal analysis revealed a biphasic pattern of expression of SLPI mRNA during early pregnancy. A considerable amount of SLPI mRNA was detected in the uterine epithelium on Day 1 of pregnancy. The level of this mRNA, however, declined sharply on Days 2 and 3 of gestation. Interestingly, on Day 4 of gestation, there was a marked resurgence in SLPI mRNA expression in the uterine epithelium. This second burst of SLPI expression diminished by Day 6 of pregnancy. The transient induction of SLPI mRNA during Days 4 and 5 overlapped with the window of implantation in the rat. Although the precise function of SLPI in the uterus eludes us presently, its known effects as a serine protease inhibitor in other tissues and its hormone-induced expression in the rat uterus immediately preceding implantation lead us to propose that this gene plays an important role in controlling excessive proteolysis and inflammation during a critical phase of early pregnancy.

Tissue-specific promoters for cancer gene therapy

Adenoviral cancer gene therapy approaches have resulted in promising recent results. Following only a decade of intense development, some of the crucial obstacles are now being overcome. Insufficient transduction has been the main limitation of earlier approaches. A new approach for increasing transduction of tumour cells is utilisation of replication-competent oncolytic agents, such as conditionally replicating adenoviruses (CRADs). The anti-tumour effect is caused by replication of the virus per se and, thus, replication must be restricted to tumour cells to protect normal tissues from damage. Tissue-specific promoters (TSPs) represent a powerful tool for decreasing the toxicity of cancer gene therapy to normal tissues and have previously been utilised for specific mutation compensation or delivery of prodrug-converting enzymes. However, TSPs can also be used for controlling crucial viral replication regulators and consequent restriction of replication to tumour cells. Initial clinical trials have demonstrated the safety and suggested efficacy for TSP-controlled CRADs as a novel approach for cancer gene therapy.

DNA microarray analysis of region-specific gene expression in the mouse epididymis

Microarray analysis was carried out to identify genes with enriched expression in the initial segment region of the mouse epididymis. A set of approximately 15 000 clones developed at the National Institutes for Aging and consisting of expressed sequence tags (ESTs) derived from pre- and peri-implantation embryos, Embryonic Day 12.5 female gonad/mesonephros, and newborn ovary were hybridized with probes generated against the initial segment (epididymal region 1) and the remainder of the epididymis (epididymal regions 2-5). The median values for the normalized ratios of region 1 to regions 2-5 from three independent experiments were averaged for each gene/EST using Genespring 5.0 software. The majority of clones showed a ratio of 1.0, suggesting they were expressed at similar levels in all epididymal regions. In addition, 123 clones exhibited 2-fold or higher expression in the initial segment, including Cres3, prostein, lipocalin 2, ALEX3, synaptotagmin-like 4, erm, and milk fat globule factor, whereas 216 clones, including elafin-like 1, lactotransferrin, Sin3B, zinc-finger protein 91, and membrane-type frizzled-related protein, showed 2-fold or higher expression in epididymal regions 2-5. Northern blot analyses of 12 clones predicted by microarray analysis to be either enriched in the initial segment (n = 8), enriched in epididymal regions 2-5 (n = 2), or similar in all regions (n = 2) were carried out. All clones exhibited the expected region-specific expression, thus confirming the microarray results. The studies presented here show a global survey of region-specific gene expression in the epididymis, identifying 15287 sequences, the majority of which have not previously been shown to be expressed in this organ.

The secretory leukoprotease inhibitor (SLPI) promoter for ovarian cancer gene therapy

BACKGROUND

Adenoviruses allow efficient transduction of dividing and non-dividing cells and their safety for the treatment of cancer has been established in clinical trials. However, one disadvantage is their promiscuous tropism. In this regard, tissue-specific promoters (TSPs) could be useful for directing transgene expression to target tissues and for reducing adverse effects in non-target tissues. We hypothesize that selective adenovirus-mediated transgene expression could be achieved through the use of the secretory leukoprotease inhibitor (SLPI) promoter in the context of ovarian cancer.

METHODS

Adenoviruses containing the SLPI promoter driving reporter and suicide gene expression were created and tested in ovarian cancer cell lines and primary tumor cells isolated from patients. To evaluate the in vivo activation of the SLPI promoter in comparison to a ubiquitous promoter, intraperitoneal delivery was performed in tumor-bearing mice, followed by analysis of survival or gene expression in normal organs and tumor.

RESULTS

The SLPI promoter retained its fidelity in an adenoviral context and was activated in both cell lines and primary cancer cells. The SLPI promoter was induced to a high degree in ovarian cancer cells while showing significantly reduced activity in normal tissues. The therapeutic efficacy of SLPI promoter-controlled gene expression was similar to the ubiquitous promoter in vitro and in an orthotopic murine model of peritoneally disseminated ovarian cancer, with higher activity than controls.

CONCLUSIONS

The SLPI promoter is a potentially useful TSP for ovarian cancer and facilitates further development of targeting strategies for improved gene therapy of ovarian carcinomas.

Mouse SWAM1 and SWAM2 are antibacterial proteins composed of a single whey acidic protein motif

Antibacterial proteins are important participants in the innate immunity system. Elafin and SLPI are the whey acidic protein (WAP) motif proteins with both antibacterial activity and antiprotease activity, and their role in innate immunity is under intense investigation. We cloned two novel antibacterial WAP motif proteins from mice, SWAM1 and SWAM2. SWAM1 and SWAM2 are composed of a signal sequence and a single WAP motif that has high homologies with the WAP motifs of elafin and SLPI. SWAM1 is constitutively expressed in kidney and epididymis, and is induced in the pneumonic lung. SWAM2 is constitutively expressed in tongue. SWAM1 and SWAM2 inhibit the growth of both Escherichia coli and Staphylococcus aureus at a IC(90) (concentration that achieves 90% inhibition) of 10 microM. Human genes LOC149709 and huWAP2 are considered to be human SWAM1 and SWAM2, respectively. These and several WAP motif proteins (WAP1, elafin, SLPI, HE4, eppin, C20orf170, LOC164237, and WFDC3) form a gene cluster on human chromosome 20, suggesting that they may be derived from the same ancestral gene by gene duplication. Our results underscore the role of the WAP motif as a skeletal motif to form antibacterial proteins, and warrant the study of antibacterial activity in other WAP motif proteins.

Neutrophil elastase and secretory leukocyte protease inhibitor in prelabor rupture of membranes, parturition and intra-amniotic infection

OBJECTIVE

Neutrophil elastase (NE), a multifunctional serine protease stored in azurophilic granules of mature neutrophils, is capable of intracellular degradation of proteins during phagocytosis and extracellular degradation of connective tissue during an inflammatory process. Secretory leukocyte protease inhibitor (SLPI) is a natural NE inhibitor present in amniotic fluid, fetal membranes and cervical mucus. An imbalance between NE and SLPI has been implicated as a mechanism of abnormal tissue destruction in chronic inflammatory diseases. The purpose of this study was to determine if parturition, premature rupture of the membranes (PROM) and microbial invasion of the amniotic cavity are associated with changes in amniotic fluid concentrations of NE and SLPI.

STUDY DESIGN

Amniotic fluid was retrieved by amniocentesis from 380 patients in the following groups: (1) preterm labor and intact membranes without microbial invasion of the amniotic cavity who delivered at term (n = 13) or prematurely (n = 26), and preterm labor with microbial invasion of the amniotic cavity (n = 9); (2) preterm PROM with (n = 34) and without (n = 51) microbial invasion of the amniotic cavity; and (3) term gestation without microbial invasion of the amniotic cavity with intact membranes not in labor (n = 63), in labor (n = 158), and with rupture of membranes not in labor (n = 26). Microbial invasion of the amniotic cavity was determined by a positive amniotic fluid culture for micro-organisms including aerobic, anaerobic and Mycoplasma species. NE and SLPI amniotic fluid levels were determined by highly specific and sensitive immunoassays.

RESULTS

Preterm PROM was associated with a significant increase in the amniotic fluid concentration of NE. Microbial invasion of the amniotic cavity was associated with a significant increase in the amniotic fluid concentration of NE in women with preterm labor and intact membranes, as well as in women with preterm PROM. Term and preterm parturition was associated with a significant increase in the amniotic fluid concentration of NE. In the absence of microbial invasion of the amniotic cavity, preterm and term PROM were associated with a significant reduction in the amniotic fluid concentration of SLPI.

CONCLUSION

Preterm PROM, microbial invasion of the amniotic cavity, and parturition at term and preterm are associated with a significant increase in the amniotic fluid concentration of NE. PROM is associated with a reduced amniotic fluid concentration of SLPI.

Cytokine-mediated induction of the human elafin gene in pulmonary epithelial cells is regulated by nuclear factor-kappaB

Elafin, a low molecular-weight proteinase inhibitor, is a member of the recently described trappin gene family. These proteins are thought to play important roles in the regulation of inflammation and are expressed in multiple epithelia. Elafin is found within the lung, and its expression can be induced by inflammatory mediators. The molecular mechanisms that mediate its induction are not understood. In this study we investigated the transcriptional regulation of the elafin gene in pulmonary epithelial cell lines. Transfection of elafin promoter constructs into the elafin-expressing pulmonary epithelial cell line A549 identified a number of positive-acting elements. Cytokine-mediated inducibility of the elafin gene promoter was shown to occur through a nuclear factor (NF)-kappaB site present within the minimal promoter. This site was shown to bind to NF-kappaB proteins within nuclear extracts from cytokine stimulated cell lines as well as to in vitro-translated RelA. Cotransfection with both RelA and NF-kappaB-inducing kinase induced reporter gene activation via this site, and mutagenesis experiments confirmed that it was crucial for induction of elafin gene activity. These results clearly identify a role for elafin in the inflammatory response of the airway epithelium to pathogenic insult and show that this response is mediated by an NF-kappaB site within the proximal promoter.

Secretory leukoprotease inhibitor augments hepatocyte growth factor production in human lung fibroblasts

Secretory leukoprotease inhibitor (SLPI), an 11.7-kD nonglycosylated serine protease inhibitor, is produced and released into the fluids of mucosal surfaces including human lung. It comprises two domains with homologous amino acid sequences: the N-terminal domain possessing antibacterial activity, and the C-terminal domain with antiprotease activity. Here we report the positive regulation of hepatocyte growth factor (HGF) production in human lung fibroblasts exerted by SLPI or its C-terminal domain under physiologic concentrations (1 to 10 microM). This HGF production by SLPI was unaffected by the addition of interleukin (IL)-1 receptor antagonist. In contrast, human skin fibroblasts exerted no SLPI-stimulated increase in HGF production, despite the fact that IL-1beta increased HGF production with an intensity similar to that of human lung fibroblasts. Both the time-course and dose-response studies in human lung fibroblasts revealed that the induction of HGF messenger RNA (mRNA) and protein occurred in parallel, indicating that the mechanism existed at the steady-state mRNA level. A synthetic elastase inhibitor failed to induce HGF, but alpha(1)-antitrypsin also stimulated HGF production in lung fibroblasts. Inactivation of the antiprotease activity of SLPI or its C-terminal domain by an oxidizing agent (N-chlorosuccinimide) abolished their stimulatory effect on HGF production. These findings demonstrate that SLPI exerts a novel HGF induction and functions as an anti-inflammatory and regenerative factor in addition to its role in protease inhibition.

Trout ovulatory proteins: site of synthesis, regulation, and possible biological function

The mRNA transcripts for trout ovulatory proteins (TOPs) are dramatically up-regulated at the time of ovulation. Previous studies indicated that TOPs were produced by the ovaries and were also present in the coelomic fluid that bathes ovulated eggs. In the present study, Western analysis indicated that TOPs were not present in the coelomic fluid prior to ovulation and therefore must be secreted into the coelomic fluid in large quantities during and after ovulation. Using in situ hybridization and immunocytochemistry, TOP mRNA and proteins were localized to the granulosa cell layer of the postovulatory follicle. A whole-follicle in vitro incubation system was used to look at the effects of various mediators on TOP mRNA and protein levels. Results of several different secondary messenger agonists suggest that TOPs are regulated through a G protein-mediated pathway that does not involve cAMP but may involve the activation of protein kinase C. Other agonists that had significant effects on TOP RNA and/or protein included transforming growth factor alpha (TGF-alpha), serine proteases, corticosteroids, bacterial lipopolysaccharide, and the nitric oxide generator SNAP ([+/-]-S-nitroso-N-acetylpenicillamine). Overall, while several compounds caused significant effects, none were able to reproduce the increase in TOP RNA and protein that occurs in vivo, suggesting that the natural mediator of TOPs may still be untested, or that a combination of mediators may be involved. Finally, coelomic fluid inhibited the growth of the Gram negative bacterium, P. aeruginosa, and this inhibition was lost following immunoprecipitation of TOPs. This suggests that one function of TOPs may be to protect ovulated eggs from bacterial infection.

Structure of the murine secretory leukoprotease inhibitor (Slpi) gene and chromosomal localization of the human and murine SLPI genes

Secretory leukoprotease inhibitor (SLPI) is a serine protease inhibitor involved in antineutrophil elastase protection at inflammatory sites. To elucidate both the function and regulation of SLPI in vivo, we isolated and characterized the mouse Slpi gene. An entire 3-kb mouse Slpi gene fragment was sequenced, including an 0. 8-kb 5'-flanking region, the 2.2-kb Slpi gene, and a 0.1-kb 3'-flanking region. The mouse Slpi gene spans 2,222 base pairs containing four exons and three introns. All splicing borders between exons and introns are conserved as predicted by GT-AG rules. Using primer extension analysis, the transcription start site was located 20 nucleotides upstream from the methionine (ATG) initiation codon. At the defined transcription start site, the sequence TCA+1GAGC is present. These results indicate that both mouse and human genomic structure are highly conserved. Using fluorescence in situ hybridization, we confirmed that, consistent with the genomic similarity, the human SLPI gene is localized on chromosome 20q12-13. 2 and the mouse homologue on chromosome 2H, which are syntenic with each other.