The IL-1 type 1 receptor is required for the development of LPS-induced airways disease

BACKGROUND: The contribution of IL-1beta signaling through the IL-1 type 1 receptor (IL-1R1) to the development of persistent LPS-induced airway disease has not been investigated. OBJECTIVE: To determine the importance of signaling through the IL-1 type 1 receptor in the development of LPS-induced airway disease. METHODS: We exposed IL-1R1-deficient (C57BL/6(IL-1RI-/-)) mice to an aerosol of LPS or filtered air for 1 day, 1 week, or 4 weeks. RESULTS: After 4 weeks of LPS inhalation, C57BL/6(IL-1RI-/-) mice failed to develop significant submucosal thickening, whereas C57BL/6 mice had significantly thickened submucosa in small, medium, and large airways compared with those of unexposed control mice. Cell proliferation in the airways of both the 1-week and 4-week LPS-exposed C57BL/6(IL-1RI-/-) mice was significantly reduced compared with LPS-exposed C57BL/6 mice. mRNA for type III alpha-3 procollagen was significantly elevated over baseline in C57BL/6 yet remained unchanged compared with baseline in C57BL/6(IL-1RI-/-) mice after 1 week or 4 weeks of LPS inhalation. mRNA for tissue inhibitor of metalloprotease 1 in C57BL/6 mice in the 1-week and 4-week groups was significantly elevated over both control mice and C57BL/6(IL-1RI-/-) mice. CONCLUSION: These data support the hypothesis that signaling through the IL-1 receptor modulates extracellular matrix homeostasis in response to inhaled LPS. CLINICAL IMPLICATIONS: Attenuating IL-1R1-mediated signaling might be an effective therapy against the development of airway remodeling in chronic inflammatory diseases.     

Indocyanine green loaded hyaluronan-derived nanoparticles for fluorescence-enhanced surgical imaging of pancreatic cancer

Pancreatic ductal adenocarcinoma is highly lethal and surgical resection is the only potential curative treatment for the disease. In this study, hyaluronic acid derived nanoparticles with physico-chemically entrapped indocyanine green, termed NanoICG, were utilized for intraoperative near infrared fluorescence detection of pancreatic cancer. NanoICG was not cytotoxic to healthy pancreatic epithelial cells and did not induce chemotaxis or phagocytosis, it accumulated significantly within the pancreas in an orthotopic pancreatic ductal adenocarcinoma model, and demonstrated contrast-enhancement for pancreatic lesions relative to non-diseased portions of the pancreas. Fluorescence microscopy showed higher fluorescence intensity in pancreatic lesions and splenic metastases due to NanoICG compared to ICG alone. The in vivo safety profile of NanoICG, including, biochemical, hematological, and pathological analysis of NanoICG-treated healthy mice, indicates negligible toxicity. These results suggest that NanoICG is a promising contrast agent for intraoperative detection of pancreatic tumors.     

An Alternative Approach to Selecting Patients for High‐risk Screening with Breast MRI

Current guidelines for adding breast MRI to annual screening mammography are based entirely upon stratification of risk, with a heavy focus on lifetime calculations. This approach is fraught with difficulty due to the reliance on mathematical models that vary widely in their calculations, the inherent age discrimination of using lifetime risks rather than short‐term incidence, and the failure to incorporate mammographic density, the latter being an independent risk as well as the greatest predictor of mammographic failure. By utilizing a system of patient selection similar to what was used in the American College of Radiology Imaging Network (ACRIN) 6666 trial for multi‐modality imaging, 33 women without a prior diagnosis of breast cancer were found to harbor mammographically occult carcinoma through MRI screening. These 33 patients represent a 2% yield, closely approximating the yields seen in prospective MRI screening trials of women at very high risk of breast cancer. Using the “~20–25%” minimum established by the American Cancer Society and later the National Comprehensive Cancer Network, the Gail model would have prompted the use of MRI in only 9 of 33 (27.3%) patients, the Claus model 1 of 33 (3%), and the Tyrer–Cuzick model 12 of 33 (36.4%). Using all three models and opting for the highest calculated risk, then including BRCA‐positivity, still would have identified only 16 of 33 (48.5%) patients with occult breast cancer discovered by MRI. Only one patient was BRCA‐positive, and none had lobular carcinoma in situ, while 6 of 33 patients (18.2%) had atypical ductal hyperplasia (ADH). Measures are proposed to refine patient selection for MRI screening through the use of short‐term or categorical risks, mammographic density, while maintaining cost‐effectiveness through longer MRI screening intervals.     

Expression of the human MUC1 mucin cDNA in a hamster pancreatic tumor cell line HP-1.

A full length cDNA for the human mucin gene, MUC1, under the control of human beta actin promoter, was transfected into a carcinogen induced hamster pancreatic ductal tumor cell line, HP-1. Transfectants were selected by resistance to geneticin. Integration of the foreign human MUC1 cDNA occurred at multiple sites in the genome of HP-1. Northern blot analysis showed MUC1 expression in cells transfected with MUC1 cDNA placed in the correct orientation, but not in control cells (HP-1 cells transfected with vector alone, or with the MUC1 cDNA placed in the antisense orientation). Western blot analysis using monoclonal antibody HMFG-2, which is reactive with the MUC1 protein, showed results consistent with the Northern blot data. Positive immunoperoxidase staining using HMFG-2 was seen in HP-1 cells transfected with MUC1 cDNA but not with untransfected or HP-1 control cells. The integration of human MUC1 mucin gene in HP-1 cells caused no significant change in the growth rate of HP-1 cells in vitro, but resulted in an enhanced growth rate for xenografts of MUC1 transfected HP-1 cells grown in nude mice.     

The development of cellular immunity to Epstein-Barr virus after allogeneic bone marrow transplantation

Epstein-Barr virus-induced lymphoproliferative disease (EBV-LPD) is a potentially lethal complication during the first 6 months after allogeneic bone marrow transplantation (BMT). To determine whether deficiencies of EBV-specific cellular immunity contribute to EBV-LPD susceptibility and distinguish patients at risk, we performed limiting dilution analysis to quantify anti-EBV cytotoxic T-lymphocyte precursor (CTLp) frequencies in 26 recipients of unmodified or T-cell-depleted (TCD) grafts from EBV-seropositive donors. At 3 months post-BMT (n = 26), only five patients had EBV CTLp frequencies in the range of seropositive normal controls, irrespective of the type of transplant administered. By 6 months post-BMT, 9 of 13 patients tested had EBV CTLp frequencies within the normal range. The time period in which these patients had deficient cellular immunity to EBV corresponds to the period in which we have observed EBV-LPD in most prior patients. One patient with a low EBV CTLp frequency at 4 months post-BMT developed an EBV-LPD. Within 2 weeks of receiving an infusion of donor peripheral blood mononuclear cells (PBMC) providing less than 1,200 EBV- specific cytotoxic T-cell precursors, populations of EBV-specific CTL in the circulation were restored to levels detected in normal seropositive adults. Concurrently, the patient achieved a regression of the EBV-LPD, which has been sustained without further therapy. These studies indicate that recipients of both unmodified and TCD marrow grafts have profound deficiencies of EBV-specific T cell-mediated immunity early posttransplant, and that the period of risk for EBV-LPD closely corresponds to this interval of severe deficiency. Treatment of one patient with EBV-LPD with marrow donor-derived PBMC induced a rapid expansion of EBV-specific cytotoxic T-cell populations that occurred contemporaneously with the clinical regression of disease.     

An inhibitory monoclonal antibody to factor X that blocks prothrombin activation but not prothrombinase enzyme assembly

A monoclonal antibody (designated alpha BFX-2b) prepared against bovine factor X inhibited factor X activity in human, bovine, porcine, rabbit, and canine plasma. In assays using purified prothrombinase components, factor Xa, factor Va, phospholipid vesicles, and calcium ion with the fluorescent active site thrombin inhibitor dansylarginyl-N-(3-ethyl-1,5- pentanediyl)amide, the antibody inhibited the conversion of prothrombin to thrombin. Antibody alpha BFX-2b also blocked prothrombinase cleavage of the macromolecular substrates prethrombin 1 and prethrombin 2 but did not inhibit factor Xa hydrolysis of the synthetic substrate benzoyl- Ile-Glu-Gly-Arg-p-nitroanilide. The antibody also prevented the inactivation of factor Xa by antithrombin III but did not prevent the inactivation by soybean trypsin inhibitor. Antibody alpha BFX-2b bound factor Xa with a stoichiometry of 1:1 and an apparent dissociation constant of 9.0 x 10(-11) mol/L as estimated from its inhibition of prothrombinase activity. Antibody alpha BFX-2b did not prevent binding of factor Xa to factor Va-phospholipid as measured by using fluorescence polarization or high-pressure liquid gel chromatography with the fluorescent Factor Xa analogue dansyl-glutamyl-glycyl-arginyl- Xa. Immunoblotting of factor X following electrophoresis on sodium dodecyl sulphate-polyacrylamide gels and transfer to nitrocellulose indicated that the antigenic determinant recognized by antibody alpha BFX-2b was found on the heavy chain of factors X and Xa. From these observations it can be concluded that antibody alpha BFX-2b recognizes a highly conserved epitope on the factor X heavy chain that is remote from the topographic sites required for prothrombinase complex assembly and substrate hydrolysis but may be located at or near a portion of the macromolecular substrate binding site.     

Regulation of phosphatidylinositol turnover in brain synaptoneurosomes: stimulatory effects of agents that enhance influx of sodium ions.

Norepinephrine and carbamoylcholine stimulate accumulation of [3H]inositol phosphates from [3H]inositol-labeled guinea pig cerebral cortical synaptoneurosomes through interaction with alpha 1-adrenergic and muscarinic receptors, respectively. In addition to such agonist, a variety of natural products that affect voltage-dependent sodium channels can markedly stimulate accumulation of [3H]inositol phosphates. These include alkaloids that activate sodium channels, such as batrachotoxin, veratridine, and aconitine; peptide toxins that alter activation or slow inactivation of sodium channels, such as various scorpion toxins from Leiurus, Centruroides, and Tityus species; and agents that cause repetitive firing of sodium channel-dependent action potentials, such as pyrethroids and pumiliotoxin B. Ouabain, and agent that will increase accumulation of internal sodium by inhibition of Na+, K+-ATPase, also stimulates formation of [3H]inositol phosphates, as does monensin, a sodium ionophore. Tetrodotoxin and saxitoxin, specific blockers of voltage-dependent sodium channels, prevent or reduce the stimulatory effects of sodium channel agents and ouabain on phosphatidylinositol turnover, while having lesser or no effect, respectively, on receptor-mediated or monensin-mediated stimulation. Removal of extracellular sodium ions markedly reduces stimulatory effects of sodium channel agents, while removal of extracellular calcium ions with EGTA blocks both receptor-mediated and sodium channel agent-mediated phosphatidylinositol turnover. The results provide evidence for a hitherto unsuspected messenger role for sodium ions in excitable tissue, whereby neuronal activity and the resultant influx of sodium will cause activation of phospholipase systems involved in hydrolysis of phosphatidylinositols, thereby generating two second messengers, the inositol phosphates, which mobilize calcium from internal stores, and the diacylglycerols, which activate protein kinase C.