Serum biomarkers in a mouse model of bacterial-induced inflammatory bowel disease

Serine-modified silver nanoparticle porous spray membrane: A novel approach to wound infection prevention and inflammation reduction

Traditional wound care preparations frequently face challenges such as complex care protocols, poor patient compliance, limited skin permeability, lack of aesthetics, and inconvenience, in addition to the risk of bacterial infection. We developed a spray film preparation containing nanocellulose and L-serine modified nanosilver, capable of rapidly forming a transparent film on the skin within minutes of application. The incorporation of nanocellulose imparted protective, moisturizing, and breathable properties to the film, allowing for easy removal after use. Moreover, our innovative application of L-serine as a precursor for synthesizing silver nanoparticles not only overcomed the limitations of current silver nanoparticle synthesis methods but also enhanced antibacterial efficacy by leveraging the inherent antimicrobial properties and bacterial targeting capability of L-serine. Specifically, the addition of nanocellulose to the spray film forming system enhanced air permeability and drug carrying capacity by creating a lightweight porous structure, while also ensuring the antimicrobial and anti-inflammatory efficacy of serine modified silver nanoparticles. Mice treated with spray film formulations containing nanocellulose and silver nanoparticles demonstrated superior wound healing, normalization of keratin thickness, increased hair follicle count, and reduced inflammatory markers. In conclusion, our study developed a spray film that integrated excellent antimicrobial properties with user convenience. This research presented innovative strategies for clinical wound care, antibacterial infection management, and post laser cosmetic treatment, with the potential to substantially enhance wound care in practical application.

Limitation of amino acid availability by bacterial populations during enhanced colitis in IBD mouse model

IMPORTANCE

Inflammatory bowel disease is associated with an increase in Enterobacteriaceae and Enterococcus species; however, the specific mechanisms are unclear. Previous research has reported the associations between microbiota and inflammation, here we investigate potential pathways that specific bacteria populations use to drive gut inflammation. Richie et al. show that these bacterial populations utilize an alternate sulfur metabolism and are tolerant of host-derived immune-response products. These metabolic pathways drive host gut inflammation and fuel over colonization of these pathobionts in the dysbiotic colon. Cultured isolates from dysbiotic mice indicated faster growth supplemented with L-cysteine, showing these microbes can utilize essential host nutrients.

ALDH1A Inhibition Suppresses Colitis and Alters α4β7 Integrin Expression on Activated T Cells in Mdr1a-/- Mice

There are limited pharmacological treatment options for inflammatory bowel disease (IBD), and some of these options are expensive and administered by injection or infusion. Thus, new cheaper and easier (oral) treatment options are needed. ALDH1A enzymes produce retinoic acid that can affect intestinal diseases such as IBD by regulating immune cells in the gut. We previously demonstrated that an orally deliverable ALDH1A inhibitor, WIN 18,466, can suppress colitis in an acute mouse model of IBD. Here, we tested the efficacy of ALDH1A inhibition in a chronic mouse model of IBD. Mdr1a-/- mice were treated with a diet containing WIN 18,446 starting 1 week prior to inducing colitis by H. bilis inoculation. Treatment was continued until the study end point and colitis was monitored based on clinical symptoms and confirmed by histological analysis. Immune cell phenotypes in colon-draining lymph nodes (cMLN) were analyzed. WIN 18,446 treatment reduced clinical symptoms and improved histopathologic colitis scores. This was associated with decreased expression of the gut homing integrin, α4β7, on T cells in cMLN; increased expression of CD103, a protein associated with tissue-resident memory T cells; and changes in dendritic cells, plasmacytoid dendritic cells and B cells in inhibitor-treated mice. ALDH1A inhibition broadly influences immune cells during colitis and is a potential new target for IBD treatment. Future studies will be needed to determine the efficacy of ALDH1A inhibition on active colitis and to evaluate its relative efficacy in comparison to approved drugs.

The Role of Extracellular Matrix Components in Inflammatory Bowel Diseases

The remodeling of extracellular matrix (ECM) within the intestine tissues, which simultaneously involves an increased degradation of ECM components and excessive intestinal fibrosis, is a defining trait of the progression of inflammatory bowel diseases (IBDs), which include ulcerative colitis (UC) and Crohn's disease (CD). The increased activity of proteases, especially matrix metalloproteinases (MMPs), leads to excessive degradation of the extracellular matrix and the release of protein and glycoprotein fragments, previously joined with the extracellular matrix, into the circulation. MMPs participate in regulating the functions of the epithelial barrier, the immunological response, and the process of wound healing or intestinal fibrosis. At a later stage of fibrosis during IBD, excessive formation and deposition of the matrix is observed. To assess changes in the extracellular matrix, quantitative measurement of the concentration in the blood of markers dependent on the activity of proteases, involved in the breakdown of extracellular matrix proteins as well as markers indicating the formation of a new ECM, has recently been proposed. This paper describes attempts to use the quantification of ECM components as markers to predict intestinal fibrosis and evaluate the healing process of the gut. The markers which reflect increased ECM degradation, together with the ones which show the process of creating a new matrix during IBD, allow the attainment of important information regarding the changes in the intestinal tissue, epithelial integrity and extracellular matrix remodeling. This paper contains evidence confirming that ECM remodeling is an integral part of directional cell signaling in the progression of IBD, and not only a basis for the ongoing processes.

The HIV protease inhibitor Saquinavir attenuates sepsis-induced acute lung injury and promotes M2 macrophage polarization via targeting matrix metalloproteinase-9

Imbalance of macrophage polarization plays an indispensable role in acute lung injury (ALI), which is considered as a promising target. Matrix metalloproteinase-9 (MMP-9) is expressed in the macrophage, and has a pivotal role in secreting inflammatory cytokines. We reported that saquinavir (SQV), a first-generation human immunodeficiency virus-protease inhibitor, restricted exaggerated inflammatory response. However, whether MMP-9 could regulate macrophage polarization and inhibit by SQV is still unknown. We focused on the important role of macrophage polarization in CLP (cecal ligation puncture)-mediated ALI and determined the ability of SQV to maintain M2 over M1 phenotype partially through the inhibition of MMP-9. We also performed a limited clinical study to determine if MMP-9 is a biomarker of sepsis. Lipopolysaccharide (LPS) increased MMP-9 expression and recombinant MMP-9 (rMMP-9) exacerbated LPS-mediated M1 switching. Small interfering RNA to MMP-9 inhibited LPS-mediated M1 phenotype and SQV inhibition of this switching was reversed with rMMP-9, suggesting an important role for MMP-9 in mediating LPS-induced M1 phenotype. MMP-9 messenger RNA levels in peripheral blood mononuclear cells of these 14 patients correlated with their clinical assessment. There was a significant dose-dependent decrease in mortality and ALI after CLP with SQV. SQV significantly inhibited LPS-mediated M1 phenotype and increased M2 phenotype in cultured RAW 264.7 and primary murine bone marrow-derived macrophages as well as lung macrophages from CLP-treated mice. This study supports an important role for MMP-9 in macrophage phenotypic switching and suggests that SQV-mediated inhibition of MMP-9 may be involved in suppressing ALI during systemic sepsis.

Protective Effects of ALDH1A Enzyme Inhibition on Helicobacter-Induced Colitis in Smad3-/- Mice are Associated with Altered α4ß7 Integrin Expression on Activated T Cells

Many inflammatory bowel disease (IBD) patients require surgical intervention due to limited pharmacological treatment options. Antibodies targeting α4ß7, a gut-homing integrin, are one of the most promising IBD treatments. As retinoic acid (RA) regulates expression of gut-homing proteins including α4ß7 integrin, we tested if ALDH1A enzymes in the RA synthesis pathway could be targeted for IBD treatment using a potent inhibitor, WIN 18,446. Age- and sex-matched Smad3^-/- mice were fed a diet with and without WIN 18,446 for 3 weeks before triggering inflammation with Helicobacter bilis infection. Colitis was evaluated by histopathology one week following the IBD trigger, and T cell subsets were evaluated before and after the IBD trigger. WIN 18,446 treatment significantly reduced IBD severity in Smad3^-/- mice and reduced expression of α4ß7 integrin on multiple activated CD4⁺ T cell subsets. This change was associated with increased ratios of induced regulatory T cells to Th17 cells during the inflammatory response in the draining lymph nodes. These studies indicate that RA reduction via ALDH1A enzyme inhibition is a potential new target for IBD treatment. Further studies are needed to examine its effects on other types of immune cells, to evaluate the efficacy window for this target, and to determine its efficacy in other animal models of IBD.

Identification of differentially expressed genes between the colon and ileum of patients with inflammatory bowel disease by gene co-expression analysis

OBJECTIVE

We aimed to identify differentially expressed genes (DEG) in patients with inflammatory bowel disease (IBD).

METHODS

RNA-seq data were obtained from the Array Express database. DEG were identified using the edgeR package. A co-expression network was constructed and key modules with the highest correlation with IBD inflammatory sites were identified for analysis. The Cytoscape MCODE plugin was used to identify key sub-modules of the protein-protein interaction (PPI) network. The genes in the sub-modules were considered hub genes, and functional enrichment analysis was performed. Furthermore, we constructed a drug-gene interaction network. Finally, we visualized the hub gene expression pattern between the colon and ileum of IBD using the ggpubr package and analyzed it using the Wilcoxon test.

RESULTS

DEG were identified between the colon and ileum of IBD patients. Based on the co-expression network, the green module had the highest correlation with IBD inflammatory sites. In total, 379 DEG in the green module were identified for the PPI network. Nineteen hub genes were differentially expressed between the colon and ileum. The drug-gene network identified these hub genes as potential drug targets.

CONCLUSION

Nineteen DEG were identified between the colon and ileum of IBD patients.

Validation studies for germ-free Smad3-/- mice as a bio-assay to test the causative role of fecal microbiomes in IBD

While the association between microbiomes and inflammatory bowel disease (IBD) is well known, establishing causal relationships between the two is difficult in humans. Germ-free (GF) mice genetically susceptible to IBD can address this question. Smad3^-/- mice with defective transforming growth factor ß signaling are a model of IBD and colon cancer. They develop IBD upon colonization with Helicobacter under specific pathogen-free conditions, suggesting a role of the microbiome in IBD in this model. Thus, we rederived Smad3^-/- mice GF to determine the potential of using these mice for testing the causative role of microbiomes in IBD. We found that fecal microbiomes from mice with IBD cause more severe gut inflammation in GF Smad3^-/- and wild type mice compared to microbiomes from healthy mice and that Helicobacter induces gut inflammation within the context of other microbiomes but not by itself. Unexpectedly, GF Smad3^+/+ and Smad3^+/- mice given IBD microbiomes develop IBD despite their lack of disease in SPF conditions upon Helicobacter infection. This was not unique to the background strain of our Smad3 model (129); both wild type C57BL/6 and 129 strains developed IBD upon fecal transfer. However, wild type Swiss Webster stock was not susceptible, indicating that the genetic background of recipient mice influences the severity of IBD following fecal transfer. Our data suggest that the microbiome is an independent risk factor contributing to IBD development, and careful characterization of new GF models is needed to understand potential sources of confounding factors influencing microbiome studies in these mice.

STAT3-Activating Cytokines: A Therapeutic Opportunity for Inflammatory Bowel Disease?

The gastrointestinal tract is lined by a single layer of epithelial cells that secrete mucus toward the lumen, which collectively separates the immune sentinels in the underlying lamina propria from the intestinal microflora to prevent aberrant immune responses. Inflammatory bowel disease (IBD) describes a group of autoimmune diseases that arise from defects in epithelial barrier function and, as a consequence, aberrant production of inflammatory cytokines. Among these, interleukin (IL)-6, IL-11, and IL-22 are elevated in human IBD patients and corresponding mouse models and, through activation of the JAK/STAT3 pathway, can both propagate and ameliorate disease. In particular, cytokine-mediated activation of STAT3 in the epithelial lining cells affords cellular protection, survival, and proliferation, thereby affording therapeutic opportunities for the prevention and treatment of colitis. In this review, we focus on recent insights gained from therapeutic modulation of the activities of IL-6, IL-11, and IL-22 in models of IBD and advocate a cautionary approach with these cytokines to minimize their tumor-promoting activities on neoplastic epithelium.

Potential urine and serum biomarkers for patients with bladder pain syndrome/interstitial cystitis

There is a lack of consensus on the pathophysiology of bladder pain syndrome/interstitial cystitis. The chronic pain symptoms of bladder pain syndrome/interstitial cystitis refractory to local treatment could be a result of central nervous system sensitization and persisting abnormalities in the bladder wall, which activate the afferent sensory system. Evidence also shows that bladder pain syndrome/interstitial cystitis is a heterogeneous syndrome and that the two subtypes, the ulcerative (classic) and non-ulcerative types, represent different disease entities. There is a need for non-invasive markers for the differential diagnoses of the subtypes of bladder pain syndrome/interstitial cystitis, and between bladder pain syndrome/interstitial cystitis and bladder sensory disorders, such as hypersensitive bladder syndrome or overactive bladder. Bladder pain syndrome/interstitial cystitis, but not overactive bladder, involves an aberrant differentiation program in the bladder urothelium that leads to altered synthesis of several proteoglycans, cell adhesion and tight junction proteins, and bacterial defense molecules. These findings have led to the rationale for identifying urinary biomarkers to detect bladder pain syndrome/interstitial cystitis in patients with frequency urgency syndrome. Recently, the markers that have been the focus of the most research are antiproliferative factor, epidermal growth factor, heparin-binding epidermal growth factor, glycosaminoglycans and bladder nitric oxide. In addition, inflammatory proteins in the urine and serum play important roles in the pathogenesis of bladder pain syndrome/interstitial cystitis. The urinary proteome is an easily accessible source of biomarkers for differentiation between inflammatory bladder disorders. Analysis of multiple urinary proteins and serum cytokines could provide a diagnostic basis for bladder pain syndrome/interstitial cystitis, and could be a tool for the differential diagnosis of bladder pain syndrome/interstitial cystitis and other sensory bladder disorders.

Matrix metalloproteinases in inflammatory bowel disease: an update

Matrix metalloproteinases (MMPs) are known to be upregulated in inflammatory bowel disease (IBD) and other inflammatory conditions, but while their involvement is clear, their role in many settings has yet to be determined. Studies of the involvement of MMPs in IBD since 2006 have revealed an array of immune and stromal cells which release the proteases in response to inflammatory cytokines and growth factors. Through digestion of the extracellular matrix and cleavage of bioactive proteins, a huge diversity of roles have been revealed for the MMPs in IBD, where they have been shown to regulate epithelial barrier function, immune response, angiogenesis, fibrosis, and wound healing. For this reason, MMPs have been recognised as potential biomarkers for disease activity in IBD and inhibition remains a huge area of interest. This review describes new roles of MMPs in the pathophysiology of IBD and suggests future directions for the development of treatment strategies in this condition.

Rac1 regulates platelet shedding of CD40L in abdominal sepsis

Matrix metalloproteinase-9 (MMP-9) regulates platelet shedding of CD40L in abdominal sepsis. However, the signaling mechanisms controlling sepsis-induced shedding of CD40L from activated platelets remain elusive. Rac1 has been reported to regulate diverse functions in platelets; we hypothesized herein that Rac1 might regulate platelet shedding of CD40L in sepsis. The specific Rac1 inhibitor NSC23766 (N6-[2-[[4-(diethylamino)-1-methylbutyl] amino]-6-methyl-4-pyrimidinyl]-2 methyl-4, 6-quinolinediamine trihydrochloride) was administered to mice undergoing cecal ligation and puncture (CLP). Levels of CD40L and MMP-9 in plasma, platelets, and neutrophils were determined by use of ELISA, western blot, and confocal microscopy. Platelet depletion abolished the CLP-induced increase in plasma levels of CD40L. Rac1 activity was significantly increased in platelets from septic animals. Administration of NSC23766 abolished the CLP-induced enhancement of soluble CD40L levels in the plasma. Moreover, Rac1 inhibition completely inhibited proteinase-activated receptor-4-induced surface mobilization and secretion of CD40L in isolated platelets. CLP significantly increased plasma levels of MMP-9 and Rac1 activity in neutrophils. Treatment with NSC23766 markedly attenuated MMP-9 levels in the plasma from septic mice. In addition, Rac1 inhibition abolished chemokine-induced secretion of MMP-9 from isolated neutrophils. Finally, platelet shedding of CD40L was significantly reduced in response to stimulation with supernatants from activated MMP-9-deficient neutrophils compared with supernatants from wild-type neutrophils, indicating a direct role of neutrophil-derived MMP-9 in regulating platelet shedding of CD40L. Our novel data suggest that sepsis-induced platelet shedding of CD40L is dependent on Rac1 signaling. Rac1 controls surface mobilization of CD40L on activated platelets and MMP-9 secretion from neutrophils. Thus, our findings indicate that targeting Rac1 signaling might be a useful way to control pathologic elevations of CD40L in the systemic circulation in abdominal sepsis.

Increased dietary vitamin D suppresses MAPK signaling, colitis, and colon cancer

Epidemiologic studies associate low serum vitamin D levels with an increased risk of colon cancer and inflammatory diseases such as inflammatory bowel disease (IBD). 129-Smad3(tm1Par)/J (Smad3(-/-)) mice are a model of bacteria-driven colitis and colon cancer when infected with Helicobacter bilis (H. bilis). Thus, we used this mouse model to determine whether increased dietary vitamin D would reduce inflammation and colon cancer. Smad3(-/-) mice were fed purified diet with either maintenance (1 IU vitamin D/g diet; maintenance) or increased concentrations of vitamin D (5 IU vitamin D/g diet; high vitamin D). One week after diet initiation, mice were inoculated with broth or H. bilis and were necropsied at several time points postinoculation to assess inflammation, dysplasia, and neoplasia incidence. At 16 weeks postinfection, 11% of mice fed high vitamin D diet had cancer compared with 41% of mice fed maintenance diet (P = 0.0121). Evaluation at an early time point (1 week postinfection) showed that animals fed high vitamin D had decreased MAPK (p-P38 and p-JNK) activation in lamina propria leukocytes as well as decreased NFκB activation in colonic epithelial cells. Reduction in MAPK and NFκB activation correlated with decreased IBD scores (2.7 vs. 15.5; P < 0.0001) as well as decreased inflammatory cell infiltrates and reduced expression of proinflammatory cytokines in cecal tissue. These findings suggest that increased dietary vitamin D is beneficial in preventing inflammation-associated colon cancer through suppression of inflammatory responses during initiation of neoplasia or early-stage carcinogenesis.

Principles for valid histopathologic scoring in research

Histopathologic scoring is a tool by which semiquantitative data can be obtained from tissues. Initially, a thorough understanding of the experimental design, study objectives, and methods is required for the pathologist to appropriately examine tissues and develop lesion scoring approaches. Many principles go into the development of a scoring system such as tissue examination, lesion identification, scoring definitions, and consistency in interpretation. Masking (aka "blinding") of the pathologist to experimental groups is often necessary to constrain bias, and multiple mechanisms are available. Development of a tissue scoring system requires appreciation of the attributes and limitations of the data (eg, nominal, ordinal, interval, and ratio data) to be evaluated. Incidence, ordinal, and rank methods of tissue scoring are demonstrated along with key principles for statistical analyses and reporting. Validation of a scoring system occurs through 2 principal measures: (1) validation of repeatability and (2) validation of tissue pathobiology. Understanding key principles of tissue scoring can help in the development and/or optimization of scoring systems so as to consistently yield meaningful and valid scoring data.

High-fat diet-induced obesity exacerbates inflammatory bowel disease in genetically susceptible Mdr1a-/- male mice

Obesity is a chronic inflammatory disease and a risk factor for disorders such as heart disease, diabetes, and cancer. A high-fat diet (HFD), a risk factor for obesity, has also been associated with inflammatory bowel disease (IBD). A proinflammatory state characterized by systemic and local increases in cytokine and chemokine levels are noted in both obesity and IBD, but it is unclear whether obesity is a risk factor for IBD. To examine any association between obesity and IBD, we chose FVB.129P2- Abcb1a(tm1Bor)N7 (Mdr1a(-/-)) mice, because this strain develops IBD spontaneously with age without a chemical or bacterial "trigger." In addition, its background strain, FVB, has been used for diet-induced obesity studies. Mdr1a(-/-) mice and wild-type (WT) mice were fed a HFD (∼60% calories from fat) or a low-fat diet (LFD; ∼11% calories from fat) for 12 wk. Obesity phenotypes examined included body weight measurements, glucose metabolism changes, and adiposity at termination of the study. IBD was determined by clinical signs, necropsy, and histopathology. We found that compared with those fed the LFD, both the Mdr1a(-/-) and WT mice fed the HFD had greater weight gains and elevated plasma leptin concentrations (P < 0.0001). When all mice were analyzed, weight gain was also associated with inflammation in mesenteric fat (R(2) = 0.5; P < 0.0001) and mesenteric lymph nodes (R(2) = 0.4; P < 0.0001). In contrast, the HFD was not associated with IBD in WT mice, whereas it exacerbated spontaneous IBD in Mdr1a(-/-) mice (P = 0.012; Fisher's exact test). Although a HFD and obesity were not associated with IBD in WT mice, our studies suggest that they are likely risk factors for IBD in a genetically susceptible host, such as Mdr1a(-/-) mice.

Platelet shedding of CD40L is regulated by matrix metalloproteinase-9 in abdominal sepsis

BACKGROUND AND OBJECTIVES

Platelet-derived CD40L is known to regulate neutrophil recruitment and lung damage in sepsis. However, the mechanism regulating shedding of CD40L from activated platelets is not known. We hypothesized that matrix metalloproteinase (MMP)-9 might cleave surface-expressed CD40L and regulate pulmonary accumulation of neutrophils in sepsis.

METHODS

Abdominal sepsis was induced by cecal ligation and puncture (CLP) in wild-type and MMP-9-deficient mice. Edema formation, CXC chemokine levels, myeloperoxidase levels, neutrophils in the lung and plasma levels of CD40L and MMP-9 were quantified.

RESULTS

CLP increased plasma levels of MMP-9 but not MMP-2. The CLP-induced decrease in platelet surface CD40L and increase in soluble CD40L levels were significantly attenuated in MMP-9 gene-deficient mice. Moreover, pulmonary myeloperoxidase (MPO) activity and neutrophil infiltration in the alveolar space, as well as edema formation and lung injury, were markedly decreased in septic mice lacking MMP-9. In vitro studies revealed that inhibition of MMP-9 decreased platelet shedding of CD40L. Moreover, recombinant MMP-9 was capable of cleaving surface-expressed CD40L on activated platelets. In human studies, plasma levels of MMP-9 were significantly increased in patients with septic shock as compared with healthy controls, although MMP-9 levels did not correlate with organ injury score.

CONCLUSIONS

Our novel data propose a role of MMP-9 in regulating platelet-dependent infiltration of neutrophils and tissue damage in septic lung injury by controlling CD40L shedding from platelets. We conclude that targeting MMP-9 may be a useful strategy to limit acute lung injury in abdominal sepsis.

Overview of mouse models of inflammatory bowel disease and their use in drug discovery

Inflammatory bowel disease (IBD), a condition that affects millions of individuals, encompasses two distinct conditions: Crohn's disease (CD) and ulcerative colitis (UC). CD is an inflammatory condition affecting any part of the digestive tract between the mouth and anus, but, most commonly, the ileum and colon. It is distinguished by the presence of granulomas in the mucosal tissue and patchy areas of transmural inflammation. UC is restricted to the colon and is manifest as continuous inflammation starting from the rectum and extending back towards the cecum. Inflammation in UC is primarily restricted to mucosal layers. Research is ongoing to understand the causality of these two diseases, and advances in understanding of their pathology have resulted from the variety of mouse models of IBD that have emerged since the early 1990s. Described in this unit are contemporary mouse models of these conditions and examples of their use in drug discovery.

Expressions of lymphotactin and its receptor, XCR, in Lewis rats with experimental autoimmune anterior uveitis

BACKGROUND

To demonstrate the expression of lymphotactin and its receptor (XCR) in the iris/ciliary body and popliteal lymph node, and to clarify their roles in experimental autoimmune anterior uveitis (EAAU).

METHODS

Uveitis was induced in Lewis rats by injection of melanin-associated antigen into the peritoneum and footpad. At defined time points, mRNA expression levels of lymphotactin and XCR in the iris/ciliary body and popliteal lymph node were measured by semiquantitative polymerase chain reaction. Lymphotactin levels in aqueous humor and serum after immunization were determined by enzyme-linked immunosorbent assay. In a separate experiment, an NF-κB inhibitor, pyrrolidine dithiocarbamate (PDTC; 200 mg/kg/day), was injected daily into the intraperitoneum after immunization. Cellular sources of lymphotactin were determined by immunhistochemical staining and flow cytometry.

RESULTS

Lymphotactin mRNA was upregulated in the iris/ciliary body with a peak level at day 14, which is in line with the disease course. XCR mRNA was expressed maximally and then declined gradually from days 5 to 21. With an expression pattern similar to that of mRNA expression, lymphotactin in aqueous humor had attracted corresponding numbers of leukocytes. PDTC markedly inhibited the expression of lymphotactin in aqueous humor and serum. Immunohistochemical staining and flow cytometry analysis revealed that the expression of lymphotactin was detected in infiltrated inflammatory cells, dominantly CD8+ T cells, and increased along with inflammation.

CONCLUSIONS

The lymphotactin and XCR interaction might direct distinct lymphocytes subsets to inflammatory sites. Lymphotactin could regulate the inflammatory process. Lymphotactin expression may be modulated, at least in part, through the NF-κB signaling pathway.

Protein microarrays for personalized medicine

BACKGROUND

Over the last 10 years, DNA microarrays have achieved a robust analytical performance, enabling their use for analyzing the whole transcriptome or for screening thousands of single-nucleotide polymorphisms in a single experiment. DNA microarrays allow scientists to correlate gene expression signatures with disease progression, to screen for disease-specific mutations, and to treat patients according to their individual genetic profiles; however, the real key is proteins and their manifold functions. It is necessary to achieve a greater understanding of not only protein function and abundance but also their role in the development of diseases. Protein concentrations have been shown to reflect the physiological and pathologic state of an organ, tissue, or cells far more directly than DNA, and proteins can be profiled effectively with protein microarrays, which require only a small amount of sample material.

CONTENT

Protein microarrays have become well-established tools in basic and applied research, and the first products have already entered the in vitro diagnostics market. This review focuses on protein microarray applications for biomarker discovery and validation, disease diagnosis, and use within the area of personalized medicine.

SUMMARY

Protein microarrays have proved to be reliable research tools in screening for a multitude of parameters with only a minimal quantity of sample and have enormous potential in applications for diagnostic and personalized medicine.

An immunoaffinity liquid chromatography-tandem mass spectrometry assay for the quantitation of matrix metalloproteinase 9 in mouse serum

An immunoaffinity liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the quantitation of the zinc endopeptidase matrix metalloproteinase 9 (MMP-9) from mouse serum. Sample preparation for the assay included magnetic bead-based enrichment using an MMP-9 antibody and was performed in a 96-well plate format using a liquid-handling robotic platform. The surrogate peptide GSPLQGPFLTAR derived from MMP-9 by trypsin digestion was monitored using an on-line capillary flow trap-release chromatography setup incorporating a series of trap columns (C18, strong cation exchange, and another C18) prior to nanoflow chromatography and nanospray ionization with selected reaction monitoring (SRM) detection. The assay was fit-for-purpose validated and found to be accurate (<15% interbatch relative error) and precise (<15% interbatch coefficient of variation) across a range from 0.03 to 7.3nM mouse MMP-9. Finally, the method was employed to measure MMP-9 concentrations in 30 naïve mouse serum samples, and results were compared with those obtained by an immunoassay.

Urine cytokines suggest an inflammatory response in the overactive bladder: a pilot study

PURPOSE

To study the hypothesis of detecting bladder inflammation associated with overactive bladder (OAB) through altered urine levels of cytokines, chemokines, and growth factors.

METHODS

Midstream urine specimens were collected from a prospective study done on eight asymptomatic control subjects and 17 idiopathic OAB patients. The urine was analyzed by a multiplex panel screen for 12 chemokines, cytokines, growth factors, and soluble receptors using Luminex™ xMAP(®) technology. Protein concentration values were normalized to the levels of creatinine.

RESULTS

This analysis revealed a significant elevation of seven key proteins in the urine of OAB patients relative to controls (*P < 0.05). A greater than tenfold elevation was measured in OAB, relative to controls, in the levels of monocyte chemotactic protein-1 (MCP-1), soluble fraction of the CD40 ligand (sCD40L) in urine was obtained from OAB patients relative to controls. At least five fold elevations were detected in the levels of macrophage inflammatory protein (MIP-1β), IL-12p70/p40, IL-5, epidermal growth factor (EGF), and growth-related oncogene GRO-α compared to controls. Significant threefold elevation was also noticed in the urine levels of sIL-2Rα, and IL-10 in the OAB group. The levels of the remaining proteins tested were not statistically significantly different from control values.

CONCLUSIONS

The presence of elevated levels in urine of inflammatory biomarkers involved in inflammation and tissue repair suggests a role for inflammation in OAB, and may help in diagnosis and treatment of this disease.