CXCL17 is a mucosal chemokine elevated in idiopathic pulmonary fibrosis that exhibits broad antimicrobial activity

The mucosal immune network is a crucial barrier preventing pathogens from entering the body. The network of immune cells that mediates the defensive mechanisms in the mucosa is likely shaped by chemokines, which attract a wide range of immune cells to specific sites of the body. Chemokines have been divided into homeostatic or inflammatory depending upon their expression patterns. Additionally, several chemokines mediate direct killing of invading pathogens, as exemplified by CCL28, a mucosa-associated chemokine that exhibits antimicrobial activity against a range of pathogens. CXCL17 was the last chemokine ligand to be described and is the 17th member of the CXC chemokine family. Its expression pattern in 105 human tissues and cells indicates that CXCL17 is a homeostatic, mucosa-associated chemokine. Its strategic expression in mucosal tissues suggests that it is involved in innate immunity and/or sterility of the mucosa. To test the latter hypothesis, we tested CXCL17 for possible antibacterial activity against a panel of pathogenic and opportunistic bacteria. Our results indicate that CXCL17 has potent antimicrobial activities and that its mechanism of antimicrobial action involves peptide-mediated bacterial membrane disruption. Because CXCL17 is strongly expressed in bronchi, we measured it in bronchoalveolar lavage fluids and observed that it is strongly upregulated in idiopathic pulmonary fibrosis. We conclude that CXCL17 is an antimicrobial mucosal chemokine that may play a role in the pathogenesis of interstitial lung diseases.     

Differential gene expression in lymphocytes from malnourished children

Malnutrition, which is widespread in developing countries, may be particularly devastating during childhood, when tissue development is occurring and nutrient requirements are great. Since protein-energy malnutrition potentially involves many cellular alterations, we have evaluated gene expression changes in lymphocytes from malnourished children using differential hybridization cloning. A cDNA library was generated from well-nourished children and differential screenings were performed with cDNAs obtained from well-nourished and malnourished children who presented with bacterial gastrointestinal infections. Differential expression was detected for genes involved in cell development and differentiation, and for genes involved in lymphocyte and mitochondrial functions. The genes detected in the present study suggest mechanisms for the changes in cell growth and immune function that are associated with protein-energy malnutrition. Two down-regulated genes in malnourished children may represent mechanisms of protection against immunosuppression. This finding clearly merits further investigation.     

Embolization itself stimulates thrombus propagation in pulmonary embolism

The role of active thrombosis in the pathophysiology of pulmonary embolism is unclear. We tested the hypothesis that venous thrombi significantly increase their thrombotic activity once they embolize into the high-flow circulation of the pulmonary arteries. Thrombotic activity was measured using an immunoassay that measures both fibrinopeptide B (FPB) as well as its most abundant metabolite des-arginine FPB. Thrombi were formed in the femoral veins of adult dogs. In one group, the thrombi were embolized without anticoagulation. In the second group, heparin (300 U/kg bolus, then 90 U x kg(-1) x h(-1) infusion) was administered before embolization to prevent subsequent thrombotic activity. Plasma FPB concentrations were significantly suppressed in the heparinized group relative to the nonheparinized group for 1 h postembolization (P = 0.038). We conclude that pulmonary embolization itself causes preexisting venous thrombi to greatly intensify their thrombotic activity and that embolization-associated thrombus propagation can be prevented by heparin.     

Secretion of biologically active human interleukin 22 (IL-22) by Lactococcus lactis

Interleukin-22 (IL-22) participates in the modulation of innate immunity and inflammation. This cytokine has important therapeutic potential, such as with ulcerative colitis, liver and lung injury, and infection, in different animal models. We generated a Lactococcus lactis strain that secretes human IL-22 under the regulation of the nisin-inducible promoter. Identification and secretion of this cytokine was demonstrated using western blots of culture supernatants from IL-22-expressing bacteria. The recombinant IL-22 protein produced by L. lactis was biologically active as determined by its ability to induce IL-10 secretion when co-cultured with a colon epithelial cell line in vitro. We consider this novel strain a promising live vaccine for various therapeutic applications.     

CDX-2, MUC-2 and B-catenin as intestinal markers in pure mucinous carcinoma of the breast

Background

Pure mucinous adenocarcinoma of the breast is a rare entity characterized by the production of variable amounts of mucin comprising 1% to 6% of breast carcinomas. Some mucinous adenocarcinomas have shown expression of intestinal differentiation markers such as MUC-2. This study examines the expression of intestinal differentiation markers in this type of breast carcinoma.

Results

Twenty-two cases of pure mucinous adenocarcinoma of the breast were assessed. Immunochemistry was performed for beta-catenin, CDX-2 and MUC-2. All cases were positive for B-catenin. MUC-2 positivity was observed in all cases; 63. 6% were 3 plus positive. All cases were negative for CDX-2.

Conclusions

These results suggest that mucinous breast carcinomas express some markers of intestinal differentiation, such as MUC-2 and beta-catenin; however, future studies with a larger series of cases and using molecular techniques that help affirm these results are needed.     

Inflammatory and Anti-inflammatory Responses Co-exist Inside Lung Granuloma of Fatal Cases of Coccidioidomycosis: A Pilot Report

Coccidioidomycosis is a fungal disease caused by Coccidioides immitis or Coccidioides posadasii. These fungi are endemic in the southern USA and northern Mexico. Immunocompromised patients are susceptible to develop severe forms of this fungal infection. Cytokines play an important role in controlling the fungal infection, but little is known about the predominant immunological environment in human lung tissue from fatal cases. Our aim was to analyze the pro-inflammatory and anti-inflammatory cytokines and monocyte/macrophages markers (CD14 and CD206) in the granulomas of six fatal cases of coccidioidomycosis. Cytokines and surface markers were higher in coccidioidomycosis cases when compared to control (P?<?0.05). CD14 positive cells were increased inside the coccidioidal granuloma when compared to the outside (P?<?0.05). No differences were found in the number of CD206+ cells inside the granuloma when compared to the outer population (P?>?0.05). Interestingly, an analysis of stain intensity signals showed an increased signaling of CD14, CD206, IL-10 and TNFα inside the granuloma when compared to the outside (P?<?0.05). iNOS and IL-12 gene expression were not detected in coccidioidomycosis cases, while IL-10, IL-6 and TGFβ gene expression were detected, but the differences when compared to healthy lungs were not significant (P?>?0.05). TNFα gene expression was lower in coccidioidomycosis cases when compared to healthy lung (P?=?0.05). In conclusion, pro- and anti-inflammatory responses co-exist inside of the granulomas of fatal cases of coccidioidomycosis and the absent of iNOS and IL-12 gene expression may be related with patient’s outcome.     

CXCL10/XCL1 fusokine elicits in vitro and in vivo chemotaxis

Fusokines are proteins formed by the fusion of two cytokines. They have greater bioavailability and therapeutic potential than individual cytokines or a combination of different cytokines. Interferon-gamma-inducible protein 10 (CXCL10) and lymphotactin (XCL1) are members of the chemotactic family of cytokines, which induce tumor regression by eliciting immune-system cell chemotaxis. We engineered a replication-deficient adenoviral system expressing CXCL10/XCL1 fusokine (Ad FIL) and assessed its chemotactic response in vitro and in vivo. The CXCL10/XCL1 fusokine elicited a greater chemotactic effect in IL-2 stimulated lymphocytes than individual or combined cytokines in vitro. CXCL10/XCL1 fusokine biological activity was demonstrated in vivo by intratumoral chemoattraction of CXCR3+ cells. Thus, this novel CXCL10/XCL1 fusokine may represent a potential tool for gene therapy treatment of cancer and other illnesses that require triggering immune-system cell recruitment.     

Accuracy of Self‐Reported Energy Intakes in Low‐Income Urban 4th Grade Minority Children

We examined the accuracy of self‐reported energy intake (rEI) in low‐income, urban minority school‐aged children at risk for obesity and associated diabetes utilizing a relatively new, simple previously published prediction equation for identifying inaccurate reports of dietary energy intake. Participants included 614 nine‐year‐old boys (51%) and girls (49%). Three 24‐h dietary recalls were collected. Children's height, weight (used to calculate BMI), and percent body fat (%BF) were measured. Physical fitness, reported family history of diabetes, and ethnicity were also collected. A previously published prediction equation was used to determine the validity of rEIs in these children to identify under‐, plausible‐, and over‐reporters. Additionally, we examined the question of whether there is a difference in reporting by sex, ethnicity, BMI, and %BF. On average, 18% of the children were at risk of being overweight, 43% were already overweight at baseline, yet these children reported consuming fewer calories on average than recommended guidelines. Additionally, reported caloric intake in this cohort was negatively associated with BMI and %BF. Using the previously described methods, 49% of participants were identified as under‐reporters, whereas 39 and 12% were identified as plausible‐ and over‐reporters, respectively. On average, children reported caloric intakes that were almost 100% of predicted energy requirement (pER) when the sedentary category was assigned. Inactivity and excessive energy intake are important contributors to obesity. With the rising rates of obesity and diabetes in children, accurate measures of energy intake are needed for better understanding of the relationship between energy intake and health outcomes.