Assessment of the Inflammatory Effects of Gut Microbiota from Human Twins Discordant for Ulcerative Colitis on Germ-free Mice.

Disturbances in gut microbiota are prevalent in inflammatory bowel disease (IBD), which includes ulcerative colitis (UC). However, whether these disturbances contribute to development of the disease or are a result of the disease is unclear. In pairs of human twins discordant for IBD, the healthy twin has a higher risk of developing IBD and a gut microbiota that is more similar to that of IBD patients as compared with healthy individuals. Furthermore, appropriate medical treatment may mitigate these disturbances. To study the correlation between microbiota and IBD, we transferred stool samples from a discordant human twin pair: one twin being healthy and the other receiving treatment for UC. The stool samples were transferred from the disease-discordant twins to germ-free pregnant dams. Colitis was induced in the offspring using dextran sodium sulfate. As compared with offspring born to mice dams inoculated with stool from the healthy cotwin, offspring born to dams inoculated with stool from the UC-afflicted twin had a lower disease activity index, less gut inflammation, and a microbiota characterized by higher α diversity and a more antiinflammatory profile that included the presence and higher abundance of antiinflammatory species such as Akkermansia spp., Bacteroides spp., and Parabacteroides spp. These findings suggest that the microbiota from the healthy twin may have had greater inflammatory properties than did that of the twin undergoing UC treatment.

Crystal structures of human immune protein FIBCD1 suggest an extended binding site compatible with recognition of pathogen-associated carbohydrate motifs.

Fibrinogen C domain-containing protein 1 (FIBCD1) is an immune protein proposed to be involved in host recognition of chitin on the surface of pathogens. As FIBCD1 readily binds acetylated molecules, we have determined the high-resolution crystal structures of a recombinant fragment of the FIBCD1 C-terminal domain complexed with small N-acetyl-containing ligands to determine the mode of recognition. All ligands bind at the conserved N-acetyl-binding site (S1) with galactose and glucose-derived ligands rotated 180° relative to each other. One subunit of a native structure derived from protein expressed in mammalian cells binds glycosylation from a neighboring subunit, in an extended binding site. Across the various structures, the primary S1 binding pocket is occupied by N-acetyl-containing ligands or acetate, with N-acetyl, acetate, or sulfate ion in an adjacent pocket S1(2). Inhibition binding studies of N-acetylglucosamine oligomers, (GlcNAc)n, n = 1, 2, 3, 5, 11, via ELISA along with microscale thermophoresis affinity assays indicate a strong preference of FIBCD1 for longer N-acetylchitooligosaccharides. Binding studies of mutant H396A, located beyond the S1(2) site, showed no significant difference from wildtype, but K381L, within the S1(2) pocket, blocked binding to the model ligand acetylated bovine serum albumin, suggesting that S1(2) may have functional importance in ligand binding. The binding studies, alongside structural definition of diverse N-acetyl monosaccharide binding in the primary S1 pocket and of additional, adjacent binding pockets, able to accommodate both carbohydrate and sulfate functional groups, suggest a versatility in FIBCD1 to recognize chitin oligomers and other pathogen-associated carbohydrate motifs across an extended surface.

Expression of FIBCD1 by intestinal epithelial cells alleviates inflammation-driven tumorigenesis in a mouse model of colorectal cancer.

Background: Colorectal cancer (CRC) ranks as the third most prevalent cancer globally, highlighting the pressing need to address its development. Inflammation plays a crucial role in augmenting the risk of CRC and actively contributes to all stages of tumorigenesis. Consequently, targeting early inflammatory responses in the intestinal tract to restore homeostasis holds significant potential for preventing and treating CRC. Fibrinogen C domain-containing 1 (FIBCD1), a chitin-binding transmembrane protein predominantly found on human intestinal epithelial cells (IECs), has garnered attention in previous research for its ability to effectively suppress inflammatory responses and promote tissue homeostasis at mucosal barriers. Methods: In this study, we investigated the role of FIBCD1 in CRC development using transgenic mice that mimic human expression of FIBCD1 at the intestinal mucosal barrier. To model aspects of CRC, we employed the azoxymethane/dextran sodium sulfate (AOM/DSS) mouse model. Additionally, we examined the expression pattern of FIBCD1 in surgical specimens obtained from human CRC patients by immunohistochemical methods. By accessing public data repositories, we further evaluated FIBCD1 expression in colon adenocarcinoma and explored survival outcomes associated with FIBCD1 expression. Results: Here, we demonstrate that FIBCD1 substantially impacts CRC development by significantly reducing intestinal inflammation and suppressing colorectal tumorigenesis in mice. Furthermore, we identify a soluble variant of FIBCD1 that is significantly increased in feces during acute inflammation. Finally, we demonstrate increased expression of FIBCD1 by immunohistochemistry in human CRC specimens at more developed tumor stages. These results are further supported by bioinformatic analyses of publicly available repositories, indicating increased FIBCD1 expression in tumor tissues, where higher expression is associated with unfavorable prognosis. Conclusion: Collectively, these findings suggest that FIBCD1 influences early inflammatory responses in the AOM/DSS model, leading to a reduction in tumor size and burden. The increased expression of FIBCD1 in human CRC samples raises intriguing questions regarding its role in CRC, positioning it as a compelling candidate and novel molecular target for future research.

The role of FIBCD1 in response to Aspergillus fumigatus in lung epithelial cells.

Chitin, a polysaccharide, is ubiquitously found in nature and has been known to be an active immunogen in mammals, and interacts with Toll-like, mannose and glucan receptors, to induce cytokine and chemokine secretions. FIBCD1 is a tetrameric type II transmembrane endocytic vertebrate receptor that binds chitin, is found in human lung epithelium and modulates lung epithelial inflammatory responses to A. fumigatus cell wall polysaccharides. We previously reported the detrimental role of FIBCD1 in a murine model of pulmonary invasive aspergillosis. However, the effect that chitin and chitin-containing A. fumigatus conidia exerts on lung epithelium following exposure through FIBCD1 is not yet fully explored. Using both in vitro and in vivo strategies, we examined how lung and lung epithelial gene expression are modified after exposure to fungal conidia or chitin fragments in the presence or absence of FIBCD1. FIBCD1 expression was associated with a decrease in inflammatory cytokines with increasing size of chitin (dimer-oligomer). Thus, our results demonstrate that FIBCD1 expression modulates cytokine and chemokine expression in response to A. fumigatus conidia that is modified by the presence of chitin particles.

Serum MFAP4, a novel potential biomarker for liver cirrhosis screening, correlates with transient elastography in NAFLD patients.

Background and Aim: Non-alcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease in different countries. Liver fibrosis is considered as the most appropriate predictor of NAFLD-associated outcome. Microfibrillar-associated protein 4 (MFAP4) is a glycoprotein located in the extracellular matrix. Circulatory MFAP4 has been suggested as a noninvasive biomarker for the assessment of hepatitis C virus and alcoholic liver disease associated liver fibrosis. In this study, we aimed to investigate the association between serum MFAP4 and liver fibrosis severity in NAFLD patients. Methods: A case-control study was conducted in which NAFLD patients (n = 25) and healthy participants (n = 12) were recruited. Liver fibrosis/cirrhosis was assessed by transient elastography (TE) and biochemical parameters were collected. Serum MFAP4 was measured by sandwich ELISA based on two monoclonal anti-MFAP4 antibodies and calibrated with a standard of recombinant MFAP4. Results: Serum MFAP4 levels increased with fibrosis severity and were highly upregulated in patients with cirrhosis (F4 fibrosis stage). In addition, serum MFAP4 levels positively correlated with TE measurement and showed significant association with the severely advanced fibrotic stage in NAFLD patients, in multiple linear regression analysis following adjustment for age, gender, and body mass index. Conclusion: This study suggests the use of MFAP4 as a potential diagnostic noninvasive biomarker for cirrhosis screening in NAFLD patients.

Impact of fibre and red/processed meat intake on treatment outcomes among patients with chronic inflammatory diseases initiating biological therapy: A prospective cohort study.

Background: Biologic disease-modifying drugs have revolutionised the treatment of a number of chronic inflammatory diseases (CID). However, up to 60% of the patients do not have a sufficient response to treatment and there is a need for optimization of treatment strategies. Objective: To investigate if the treatment outcome of biological therapy is associated with the habitual dietary intake of fibre and red/processed meat in patients with a CID. Methods: In this multicentre prospective cohort study, we consecutively enrolled 233 adult patients with a diagnosis of Crohn's Disease, Ulcerative Colitis, Rheumatoid Arthritis (RA), Axial Spondyloarthritis, Psoriatic Arthritis and Psoriasis, for whom biologic therapy was planned, over a 3 year period. Patients with completed baseline food frequency questionnaires were stratified into a high fibre/low red and processed meat exposed group (HFLM) and an unexposed group (low fibre/high red and processed meat intake = LFHM). The primary outcome was the proportion of patients with a clinical response to biologic therapy after 14-16 weeks of treatment. Results: Of the 193 patients included in our primary analysis, 114 (59%) had a clinical response to biologic therapy. In the HFLM group (N = 64), 41 (64%) patients responded to treatment compared to 73 (56%) in the LFHM group (N = 129), but the difference was not statistically significant (OR: 1.48, 0.72-3.05). For RA patients however, HFLM diet was associated with a more likely clinical response (82% vs. 35%; OR: 9.84, 1.35-71.56). Conclusion: Habitual HFLM intake did not affect the clinical response to biological treatment across CIDs. HFLM diet in RA patients might be associated with better odds for responding to biological treatment, but this would need confirmation in a randomised trial. Trial registration: (clinicaltrials.gov), identifier [NCT03173144].

FIBCD1 is an endocytic GAG receptor associated with a novel neurodevelopmental disorder.

Whole-exome sequencing of two patients with idiopathic complex neurodevelopmental disorder (NDD) identified biallelic variants of unknown significance within FIBCD1, encoding an endocytic acetyl group-binding transmembrane receptor with no known function in the central nervous system. We found that FIBCD1 preferentially binds and endocytoses glycosaminoglycan (GAG) chondroitin sulphate-4S (CS-4S) and regulates GAG content of the brain extracellular matrix (ECM). In silico molecular simulation studies and GAG binding analyses of patient variants determined that such variants are loss-of-function by disrupting FIBCD1-CS-4S association. Gene knockdown in flies resulted in morphological disruption of the neuromuscular junction and motor-related behavioural deficits. In humans and mice, FIBCD1 is expressed in discrete brain regions, including the hippocampus. Fibcd1 KO mice exhibited normal hippocampal neuronal morphology but impaired hippocampal-dependent learning. Further, hippocampal synaptic remodelling in acute slices from Fibcd1 KO mice was deficient but restored upon enzymatically modulating the ECM. Together, we identified FIBCD1 as an endocytic receptor for GAGs in the brain ECM and a novel gene associated with an NDD, revealing a critical role in nervous system structure, function and plasticity.

Cross-species high-resolution transcriptome profiling suggests biomarkers and therapeutic targets for ulcerative colitis.

Background: Ulcerative colitis (UC) is a disorder with unknown etiology, and animal models play an essential role in studying its molecular pathophysiology. Here, we aim to identify common conserved pathological UC-related gene expression signatures between humans and mice that can be used as treatment targets and/or biomarker candidates. Methods: To identify differentially regulated protein-coding genes and non-coding RNAs, we sequenced total RNA from the colon and blood of the most widely used dextran sodium sulfate Ulcerative colitis mouse. By combining this with public human Ulcerative colitis data, we investigated conserved gene expression signatures and pathways/biological processes through which these genes may contribute to disease development/progression. Results: Cross-species integration of human and mouse Ulcerative colitis data resulted in the identification of 1442 genes that were significantly differentially regulated in the same direction in the colon and 157 in blood. Of these, 51 genes showed consistent differential regulation in the colon and blood. Less known genes with importance in disease pathogenesis, including SPI1, FPR2, TYROBP, CKAP4, MCEMP1, ADGRG3, SLC11A1, and SELPLG, were identified through network centrality ranking and validated in independent human and mouse cohorts. Conclusion: The identified Ulcerative colitis conserved transcriptional signatures aid in the disease phenotyping and future treatment decisions, drug discovery, and clinical trial design.

FIBCD1 Deficiency Decreases Disease Severity in a Murine Model of Invasive Pulmonary Aspergillosis.

Aspergillus fumigatus is a ubiquitous mold associated with the development of pulmonary diseases that include invasive pulmonary aspergillosis (IPA), an often fatal opportunistic infection. FIBCD1 is a transmembrane endocytic membrane receptor widely expressed on human epithelium. Although FIBCD1 was previously shown to bind chitin, modulate fungal colonization of the gut, and inhibit intestinal inflammation, the role of FIBCD1 in the context of lung fungal infection remains unknown. In this study, we observed that mortality, fungal burden, and tissue histopathology were decreased in the absence of FIBCD1 in murine IPA. Quantitative RT-PCR analyses demonstrated decreased inflammatory cytokines in the lungs of neutrophil-depleted FIBCD1-/- mice with IPA, when compared with wild-type controls. In contrast, inflammatory cytokines were increased in immune-competent FIBCD1-/- mice after fungal aspiration, suggesting that the presence of neutrophils is associated with cytokine modulation. In contrast to the clear IPA phenotype, FIBCD1-/- mice with systemic infection or bleomycin-induced lung injury exhibited similar morbidity and mortality when compared with their wild-type counterparts. Thus, our study identifies a detrimental role of FIBCD1 in IPA.

Corrigendum to 'Level of MFAP4 in ascites independently predicts 1-year transplant-free survival in patients with cirrhosis' [JHEP Reports 3 (2021) 100287].

[This corrects the article DOI: 10.1016/j.jhepr.2021.100287.].

No effect of deleted in malignant brain tumors 1 deficiency on chemotherapy induced murine intestinal mucositis.

Mucositis is a serious adverse effect of chemotherapeutic treatment. During intestinal mucositis, the mucosal barrier is compromised, increasing the risk of severe infections. Mucositis necessitates dose reduction or pauses in treatment, which affect the outcome of the treatment. Deleted in malignant brain tumors 1 (DMBT1) is a secreted scavenger protein with effects on innate immunity and epithelial regeneration. We have previously shown that jejunal DMBT1 expression is increased in piglets during chemotherapeutic treatment. We hypothesized that DMBT1 ameliorates doxorubicin-induced mucositis. Individually-caged Dmbt1+/+ (WT) and Dmbt1-/- (KO) female mouse littermates received intraperitoneal injections of either doxorubicin or saline. They were euthanized after three (D3) or seven days (D7). Weight loss was monitored every day, and serum citrulline levels were measured at termination. Intestinal tissue was analyzed for the expression of DMBT1 and proinflammatory cytokines (IL-1ß, IL-6, and TNF). Specimens from the small intestines and colon were scored for inflammation and epithelial and mucosal architecture changes. We detected no effect of DMBT1 on weight loss, serum citrulline levels, expression of proinflammatory cytokines, or histologic damage. We detected a significant increase in crypt depth in WT mice compared to that in KO mice on D3. In conclusion, DMBT1 does not affect doxorubicin-induced mucositis in mice.

Level of MFAP4 in ascites independently predicts 1-year transplant-free survival in patients with cirrhosis.

BACKGROUND & AIMS: Prognostic models of cirrhosis underestimate disease severity for patients with cirrhosis and ascites. Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein linked to hepatic neoangiogenesis and fibrogenesis. We investigated ascites MFAP4 as a predictor of transplant-free survival in patients with cirrhosis and ascites. METHODS: A dual-centre observational study of patients with cirrhosis and ascites recruited consecutively in relation to a paracentesis was carried out. Patients were followed up for 1 year, until death or liver transplantation (LTx). Ascites MFAP4 was tested with the model for end-stage liver disease (MELD-Na), CLIF Consortium Acute Decompensation (CLIF-C AD), and Child-Pugh score in Cox regression models. RESULTS: Ninety-three patients requiring paracentesis were included. Median ascites MFAP4 was 29.7 U/L [22.3-41.3], and MELD-Na was 19 [16-23]. A low MELD-Na score (<20) was observed in 49 patients (53%). During follow-up, 20 patients died (22%), and 6 received LTx (6%). High ascites MFAP4 (>29.7 U/L) was associated with 1-year transplant-free survival (p = 0.002). In Cox regression, ascites MFAP4 and MELD-Na independently predicted 1-year transplant-free survival (hazard ratio [HR] = 0.97, p = 0.03, and HR = 1.08, p = 0.01, respectively). Ascites MFAP4 and CLIF-C AD also predicted survival independently (HR = 0.96, p = 0.02, and HR = 1.05, p = 0.03, respectively), whereas only ascites MFAP4 did, controlling for the Child-Pugh score (HR = 0.97, p = 0.03, and HR = 1.18, p = 0.16, respectively). For patients with MELD-Na <20, ascites MFAP4 but not ascites protein predicted 1-year transplant-free survival (HR 0.91, p = 0.02, and HR = 0.94, p = 0.17, respectively). CONCLUSIONS: Ascites MFAP4 predicts 1-year transplant-free survival in patients with cirrhosis and ascites. In patients with low MELD-Na scores, ascites MFAP4, but not total ascites protein, significantly predicted 1-year transplant-free survival. LAY SUMMARY: Patients with cirrhosis who have fluid in the abdomen, ascites, are at an increased risk of death and in need for liver transplantation. Our study identified patients with ascites and a poor prognosis by measuring microfibrillar associated protein 4 (MFAP4), a protein present in the abdominal fluid. Patients with low levels of the MFAP4 protein are at particularly increased risk of death or liver transplantation, suggesting that clinical care should be intensified in this group of patients.

Peptidoglycan Recognition Peptide 2 Aggravates Weight Loss in a Murine Model of Chemotherapy-Induced Gastrointestinal Toxicity.

Introduction: Chemotherapy-induced gastrointestinal toxicity (CIGT) is a frequent, severe and dose-limiting side effect. Few treatments have proven effective for CIGT. CIGT is characterized by activation of the nuclear factor kappa B pathway which, leads to upregulation of proinflammatory cytokines. The innate immune protein peptidoglycan recognition peptide 2 (PGLYRP2) binds to and hydrolyzes microbial peptidoglycan. Expression of PGLYRP2 is upregulated in the intestine of chemotherapy-treated piglets. In this experimental study, we investigated the role of Pglyrp2 in the development and severity of murine CIGT. Methods: Pglyrp2 wildtype and Pglyrp2 knockout mice received intraperitoneal injections of chemotherapy (Doxorubicin 20 mg/kg) to induce CIGT. Weight was monitored daily, and animals were euthanized after 2 or 7 days. Expression of proinflammatory cytokines in the jejunum was measured by quantitative real-time polymerase-chain reaction and enzyme-linked immunosorbent assay. Villus height, crypt depth, and histologic inflammation were evaluated on haematoxylin and eosin stained tissue specimens. Results: Chemotherapeutic treatment induced weight loss (p < 0.05), shortening of the small intestine (p < 0.05), elongation of villus height (p < 0.05), increased crypt depth (p < 0.05), and led to elevated mRNA levels of II1ß (p < 0.05), II6 (p < 0.05), and Tnf (p < 0.001) at day 2. Protein levels of IL1ß, IL6, and TNFα did not change after exposure to chemotherapy. Doxorubicin treated wildtype mice had a more pronounced weight loss compared to knockout mice from day 3 to day 7 (D3-D6: p < 0.05 and D7: p < 0.01). No other phenotypic differences were detected. Conclusion: Pglyrp2 aggravates chemotherapy-induced weight loss but does not induce a specific pattern of inflammation and morphological changes in the small intestine.

Intestinal protozoan infections shape fecal bacterial microbiota in children from Guinea-Bissau.

Intestinal parasitic infections, caused by helminths and protozoa, are globally distributed and major causes of worldwide morbidity. The gut microbiota may modulate parasite virulence and host response upon infection. The complex interplay between parasites and the gut microbiota is poorly understood, partly due to sampling difficulties in remote areas with high parasite burden. In a large study of children in Guinea-Bissau, we found high prevalence of intestinal parasites. By sequencing of the 16S rRNA genes of fecal samples stored on filter paper from a total of 1,204 children, we demonstrate that the bacterial microbiota is not significantly altered by helminth infections, whereas it is shaped by the presence of both pathogenic and nonpathogenic protozoa, including Entamoeba (E.) spp. and Giardia (G.) lamblia. Within-sample diversity remains largely unaffected, whereas overall community composition is significantly affected by infection with both nonpathogenic E. coli (R2 = 0.0131, P = 0.0001) and Endolimax nana (R2 = 0.00902, P = 0.0001), and by pathogenic E. histolytica (R2 = 0.0164, P = 0.0001) and G. lamblia (R2 = 0.00676, P = 0.0001). Infections with multiple parasite species induces more pronounced shifts in microbiota community than mild ones. A total of 31 bacterial genera across all four major bacterial phyla were differentially abundant in protozoan infection as compared to noninfected individuals, including increased abundance of Prevotella, Campylobacter and two Clostridium clades, and decreased abundance of Collinsella, Lactobacillus, Ruminococcus, Veillonella and one Clostridium clade. In the present study, we demonstrate that the fecal bacterial microbiota is shaped by intestinal parasitic infection, with most pronounced associations for protozoan species. Our results provide insights into the interplay between the microbiota and intestinal parasites, which are valuable to understand infection biology and design further studies aimed at optimizing treatment strategies.

FIBCD1 ameliorates weight loss in chemotherapy-induced murine mucositis.

PURPOSE: Chemotherapy-induced gastrointestinal toxicity is a common adverse event during chemotherapeutic treatment. No uniformly applicable strategies exist to predict, prevent, or treat gastrointestinal toxicity. Thus, a goal of mucositis research is to identify targets for therapeutic interventions and individualized risk prediction. Fibrinogen C domain containing 1 (FIBCD1) is a transmembrane protein expressed in human intestinal epithelial cells with functions in the innate immune system. Previous observations have shown that FIBCD1 ameliorates dextran sulfate sodium (DSS)-induced intestinal inflammation in vivo. We evaluated the effect of FIBCD1 in a murine model of chemotherapy-induced gastrointestinal toxicity and inflammation. METHODS: Transgenic (Tg) mice overexpressing FIBCD1 in the intestinal epithelium (Fibcd1Tg) and wild-type (WT) littermates (C57BL/6N) were randomized to receive an intraperitoneal injection of doxorubicin 20 mg/kg or saline and were terminated 2 or 7 days after the injection. Gastrointestinal toxicity was evaluated by weight change, intestinal length, villus height/crypt depth, and histological mucositis score. Expression of inflammatory markers (IL-6, IL-1ß, and Tnfα) was measured by quantitative real-time PCR in intestinal tissue samples. RESULTS: Following doxorubicin treatment, WT mice exhibited an increased weight loss compared with Tg littermates (p < 0.001). No differences between genotypes were seen in mucositis score, intestinal length, villus height/crypt depth, or IL-6, IL-1ß, and Tnfα expression. CONCLUSION: Our findings suggest that FIBCD1 could ameliorate chemotherapy-induced gastrointestinal toxicity by reducing weight loss; however, the mechanism of this possible protective effect remains to be defined warranting additional investigations.

Restoration of miR-330 expression suppresses lung cancer cell viability, proliferation, and migration.

Lung cancer is one of the most common cancers and its incidence is rising around the world. Various studies suggest that miR-330 acts as a tumor-suppressor microRNA (miRNA) in different types of cancers, but precisely how has remained unclear. In this study, we investigate miR-330 expression in lung cancer patient samples, as well as in vitro, by studying how normalization of miR-330 expression affects lung cancer cellular phenotypes such as viability, apoptosis, proliferation, and migration. We establish that low miR-330 expression predicts poor lung cancer prognosis. Stable restoration of reduced miR-330 expression in lung cancer cells reduces cell viability, increases the fraction of apoptotic cells, causes G2/M cell cycle arrest, and inhibits cell migration. These findings are substantiated by increased mRNA and protein expression of markers for apoptosis via the intrinsic pathway, such as caspase 9, and decreased mRNA and protein expression of markers for cell migration, such as vimentin, C-X-C chemokine receptor type 4, and matrix metalloproteinase 9. We showed that reduced miR-330 expression predicts poor lung cancer survival and that stable restoration of miR-330 expression in lung cancer cells has a broad range of tumor-suppressive effects. This indicates that miR-330 is a promising candidate for miRNA replacement therapy for lung cancer patients.

Generation of novel trimeric fragments of human SP-A and SP-D after recombinant soluble expression in E. coli.

Surfactant treatment for neonatal respiratory distress syndrome has dramatically improved survival of preterm infants. However, this has resulted in a markedly increased incidence of sequelae such as neonatal chronic inflammatory lung disease. The current surfactant preparations in clinical use lack the natural lung defence proteins surfactant proteins (SP)-A and D. These are known to have anti-inflammatory and anti-infective properties essential for maintaining healthy non-inflamed lungs. Supplementation of currently available animal derived surfactant therapeutics with these anti-inflammatory proteins in the first few days of life could prevent the development of inflammatory lung disease in premature babies. However, current systems for production of recombinant versions of SP-A and SP-D require a complex solubilisation and refolding protocol limiting expression at scale for drug development. Using a novel solubility tag, we describe the expression and purification of recombinant fragments of human (rfh) SP-A and SP-D using Escherichia coli without the need for refolding. We obtained a mean (± SD) of 23.3 (± 5.4) mg and 86 mg (± 3.5) per litre yield of rfhSP-A and rfhSP-D, respectively. rfhSP-D was trimeric and 68% bound to a ManNAc-affinity column, giving a final yield of 57.5 mg/litre of highly pure protein, substantially higher than the 3.3 mg/litre obtained through the standard refolding protocol. Further optimisation of this novel lab based method could potentially make rfhSP-A and rfhSP-D production more commercially feasible to enable development of novel therapeutics for the treatment of lung infection and inflammation.

Immunohistochemical Localization of Deleted in Malignant Brain Tumors 1 in Normal Human Tissues.

Deleted in malignant brain tumors 1 (DMBT1) is part of the innate immune system and is expressed on mucosal surfaces in various tissues throughout the human body. However, to date, the localization of DMBT1 has not been investigated systematically and comprehensively in normal human tissues. In this study, we analyzed the mRNA expression of DMBT1 in human tissue by quantitative real-time PCR and examined its localization and distribution in the tissue by immunohistochemical staining using the monoclonal DMBT1 antibody HYB213-6. Anti-ovalbumin was used as an isotype control. The highest level of mRNA expression of DMBT1 was found in the small intestine, and the expression level was high throughout the luminal digestive tract. The expression of DMBT1 was especially high in the luminal digestive tract and salivary glands. The lowest expression level was found in the spleen. Immunohistochemical staining showed a high expression level of DMBT1 on mucosal surfaces throughout the body. There was a clear correlation between the mRNA expression and immunohistochemical expression of DMBT1 in the tissue. DMBT1 is strongly expressed on mucosal surfaces and in salivary glands.

Prediction of liver fibrosis severity in alcoholic liver disease by human microfibrillar-associated protein 4.

BACKGROUND: Alcoholic liver disease (ALD) is a public health concern that is the cause of half of all cirrhosis-related deaths. Early detection of fibrosis, ideally in the precirrhotic stage, is a key strategy for improving ALD outcomes and for preventing progression to cirrhosis. Previous studies identified the blood-borne marker human microfibrillar-associated protein 4 (MFAP4) as a biomarker for detection of hepatitis C virus (HCV)-related fibrosis. AIM: To evaluate the diagnostic accuracy of MFAP4 to detect ALD-induced fibrosis. METHOD: We performed a prospective, liver biopsy-controlled study involving 266 patients with prior or current alcohol overuse. Patients were split into a training and a validation cohort. RESULTS: MFAP4 was present in fibrotic hepatic tissue and serum MFAP4 levels increased with fibrosis grade. The area under the receiver operating characteristic curve (AUROC) for detection of cirrhosis was 0.91 (95% CI 0.85-0.96) in the training cohort and 0.91 (95% CI 0.79-1.00) in the validation cohort. For detection of advanced fibrosis, the AUROC was 0.88 (95% CI 0.81-0.94) in the training cohort and 0.92 (95% CI 0.83-1.00) in the validation cohort. The diagnostic accuracy did not differ between MFAP4 and the enhanced liver fibrosis (ELF) test or transient elastography (TE) in an intention-to-diagnose analysis. MFAP4 did not predict hepatic decompensation in a time-to-decompensation analysis in a subgroup of patients with cirrhosis. CONCLUSION: MFAP4 is a novel biomarker that can detect ALD-related fibrosis with high accuracy.