Chemokine networks in vivo: involvement of C-X-C and C-C chemokines in neutrophil extravasation in vivo in response to TNF-alpha

In this study, we have evaluated the role of specific chemotactic cytokines in leukocyte recruitment to s.c. tissue in response to TNF-alpha in vivo. Injection of TNF-alpha into s.c. air pouches led to a rapid, transient accumulation of leukocytes. Maximal accumulation of leukocytes in the air pouch was observed at between 2 and 4 h after injection of TNF-alpha. The cellular exudate comprised predominantly neutrophils, with smaller numbers of eosinophils and mononuclear phagocytes also being recruited. However, lymphocyte recruitment was not observed. TNF-alpha injection induced a time-dependent increase in the levels of immunoreactive macrophage inflammatory protein (MIP)-2, MIP-1alpha, and JE in the pouch exudate as well as increased steady-state mRNA levels of KC, MIP-2, MIP-1alpha, and JE in the tissue lining the s.c. pouch and of MIP-2, MIP-1alpha, and JE in the exudate cell population. Passive immunization with specific Abs directed against each of these chemokines significantly inhibited the accumulation of neutrophils, mononuclear phagocytes, and eosinophils in response to TNF-alpha. Taken together, these data demonstrate the existence of a chemokine network in vivo involving at least four individual chemokines that regulates recruitment of the major peripheral blood granulocytes and mononuclear phagocytes to s.c. sites during acute inflammation. To our knowledge, these data are also the first demonstration that the C-C chemokine JE is involved in neutrophil recruitment in a physiologic system in vivo.     

Establishment of tumor cell culture (ILA) derived from hamster pancreatic islets treated with BOP

ILA cells were established from tumors induced by the pancreatic carcinogen N-nitrosobis(2-oxopropyl)amine (BOP) in hamster islets. The proliferation, morphology, karyotype, immunoreactivity with certain antibodies and growth factor secretion of these tumor cells were compared with the same parameters in tumor cells induced by BOP in hamster ductal cells (TAKA-1-BOP) established in a previous study. Minor differences were found in the morphology and ultrastructure of the 2 cell lines. Contrary to TAKA-1-BOP cells, ILA cells did not express cytokeratins 8.13, 13 or 18 but did express DU-PAN-2 and TAG-72, 2 known human pancreatic cancer-associated antigens. No endocrine cell markers were expressed. A significant difference also was found in the chromosomal pattern in that there were more abnormalities and marker chromosomes in ILA cells than in TAKA-1-BOP cells and the Y or X chromosomes were missing in ILA cells. ILA cells produced TGF-alpha, IGF-I, bombesin and gastrin and expressed specific binding sites for hEGF. TGF-alpha secretion from ILA cells was much greater than that from TAKA-1-BOP cells. Our results indicate that pancreatic cancer cells grown in vitro are not a single clone. We conclude that there are some genetic and biological differences between tumors arising from pancreatic duct and islets and that pancreatic ductal adenocarcinomas originating from islets have a profound malignant potential.     

Transduction of CD34+ hematopoietic progenitor cells with an antitat gene protects T-cell and macrophage progeny from AIDS virus infection

Transduction of hematopoietic stem cells with genes that inhibit human immunodeficiency virus (HIV) replication has the potential to reconstitute immune function in individuals with AIDS. We evaluated the ability of an autoregulated gene, antitat, to inhibit replication of simian immunodeficiency virus (SIV) and HIV type 1 (HIV-1) in hematopoietic cells derived from transduced progenitor cells. The antitat gene expresses an antiviral RNA encoding polymeric Tat activation response elements in combination with an antisense tat moiety under the control of the HIV-1 long terminal repeat. CD34+ hematopoietic progenitor cells were transduced with a retroviral vector containing the antitat gene and then cultured under conditions that support in vitro differentiation of T cells or macrophage-like cells. Rhesus macaque CD4+ T cells and macrophage-like cells derived from CD34+ bone marrow cells transduced with the antitat gene were highly resistant to challenge with SIV, reflecting a 2- to 3-log reduction in peak SIV replication compared with controls. Similarly, human CD4+ T cells derived from CD34+ cord blood cells transduced with antitat were also resistant to infection with HIV-1. No evidence for toxicity of the antitat gene was observed in any of five different lineages derived from transduced hematopoietic cells. These results demonstrate that a candidate therapeutic gene introduced into hematopoietic progenitor cells can retain the ability to inhibit AIDS virus replication following T-cell differentiation and support the potential use of the antitat gene for stem cell gene therapy.     

Adjunctive treatment of compartment syndrome with hyperbaric oxygen

Trauma-induced compartment syndrome and other acute traumatic peripheral ischemias have been effectively treated with hyperbaric oxygen therapy. We describe a case of compartment syndrome associated with an acute exertional injury. After surgical decompression, hyperbaric oxygen therapy reduced edema and improved tissue viability. The mechanisms of hyperbaric oxygen applicable to the pathophysiology of compartment syndrome are described. We believe that hyperbaric oxygen is a useful intervention in the management of compartment syndrome.     

Cigarette smoking and risk of prostate cancer: a population-based case-control study in Ontario and British Columbia, Canada

The relationship between cigarette smoking and risk of prostate cancer was examined in a case-control study conducted in Ontario and British Columbia, Canada. In each centre, cases were men with a histologically confirmed diagnosis of adenocarcinoma of the prostate notified to the provincial cancer registry. In Ontario, controls were selected randomly from assessment lists maintained by the Ontario Ministry of Revenue and were frequency matched to the cases on age. In British Columbia, controls were also frequency matched to the cases on age and were selected randomly from a roster maintained by the Medical Services Plan of British Columbia. The study in Ontario was conducted between April 1990 and April 1992, and that in British Columbia was conducted between January 1989 and December 1991. In all, the study included 408 cases (207 in Ontario and 201 in British Columbia) and 407 controls (207 in Toronto and 200 in British Columbia (one case was unmatched). Overall, there was little variation in risk of prostate cancer with pack-years of cigarette consumption (filter and non-filter cigarettes combined), and there was no evidence for an effect confined to filter or non-filter cigarettes. There was some evidence for a positive association with non-filter cigarettes in British Columbia, but on formal testing for heterogeneity, this finding was not inconsistent with the absence of an association in Ontario. There was also little variation in risk by years since first smoked or (for ex-smokers) by years since quitting. These data provide little support for an association between cigarette smoking and prostate cancer risk.     

Purification and characterization of an endo-1,3-beta-glucanase from Aspergillus fumigatus

An endo-1,3-beta-glucanase was purified from a cell wall autolysate of Aspergillus fumigatus. This beta-glucanase activity was associated with a glycosylated 74-kDa protein. Using a sensitive colorimetric assay and a high-performance anion-exchange chromatography with a pulsed electrochemical detector for product analysis, it was shown that the endoglucanase hydrolysed exclusively linear 1,3-beta-glucan chains, had an optimum pH of 7.0 and an optimum temperature of 60 degrees C. A substrate kinetic study gave a Km value of 0.3 mg/ml for soluble (laminarin and laminari-oligosaccharides) and 1.18 mg/ml for insoluble (curdlan) 1,3-beta-glucan. Laminari-oligosaccharide degradation, analysed by HPLC, showed that the endoglucanase bind to the subtrate at several positions and suggested that the active site of the enzyme recognized five glucose units linked by a 1,3-beta bond. The association of the present endo-1,3-beta-glucanase with the cell wall of A. fumigatus suggests a putative role for this enzyme during cell-wall morphogenesis.     

Expression profile of hyaluronidase mRNA transcripts in the kidney and in renal cells

Technical innovation has recently resulted in the routine use of gated-SPECT in myocardial perfusion imaging. In the present work we compare estimates of left ventricular function (LV cavity) by gated-SPECT with those of conventional echocardiography in a group of 95 ischemic patients, 49 of whom had previous myocardial infarction. Kappa analysis showed correlation coefficients of 0.67 for global function in the whole group and of 0.68 in patients with MI, as well as of 0.56 in the anterior wall, and 0.55 in the inferior wall. With these data, we believe that the technique is useful and it adds to the conventional perfusion SPECT imaging. Also, it is conveniently validated against echocardiography in our hands.     

Genetic and immunologic analyses of PlpE, a lipoprotein important in complement-mediated killing of Pasteurella haemolytica serotype 1

Pasteurella haemolytica serotype 1 is the bacterium most commonly associated with bovine shipping fever. The presence of antibodies against P. haemolytica outer membrane proteins (OMPs) correlates statistically with resistance to experimental P. haemolytica challenge in cattle. Until now, specific P. haemolytica OMPs which elicit antibodies that function in host defense mechanisms have not been identified. In this study, we have cloned and sequenced the gene encoding one such protein, PlpE. Analysis of the deduced amino acid sequence revealed that PlpE is a lipoprotein and that it is similar to an Actinobacillus pleuropneumoniae lipoprotein, OmlA. Affinity-purified, anti-PlpE antibodies recognize a protein in all serotypes of P. haemolytica except serotype 11. We found that intact P. haemolytica and recombinant E. coli expressing PlpE are capable of absorbing anti-PlpE antibodies from bovine immune serum, indicating that PlpE is surface exposed in P. haemolytica and assumes a similar surface-exposed conformation in E. coli. In complement-mediated killing assays, we observed a significant reduction in killing of P. haemolytica when bovine immune serum that was depleted of anti-PlpE antibodies was used as the source of antibody. Our data suggest that PlpE is surface exposed and immunogenic in cattle and that antibodies against PlpE contribute to host defense against P. haemolytica.     

A logistic dose-ranging method for phase I clinical investigations trials

This paper describes an alternative to the continual reassessment method (CRM) for phase I trials. The logistic dose ranging strategy (LDRS) uses logistic regression and a dose allocation scheme similar to the CRM. It can easily be implemented from any logistic regression program. The LDRS can be a stand alone dose allocation scheme or it can be incorporated into standard three on a dose strategies to indicate when escalation can proceed more rapidly. Finally, the effect of covariates such as age or comorbid conditions on the toxicity expected for the dose selected for a phase II trial can be examined.