Citations

Abstract In idiopathic pulmonary fibrosis, the quantitation of disease severity using pulmonary function tests is often confounded by emphysema. We have identified the composite physiologic index (CPI) most closely reflecting the morphologic extent of pulmonary fibrosis. Consecutive patients with a clinical/computed tomography (CT) diagnosis of idiopathic pulmonary fibrosis (n = 212) were divided into group I (n = 106) and group II (n = 106). The CPI was derived in group I (by fitting pulmonary function tests against disease extent on CT) and was tested in Group II. The formula for the CPI was as follows: extent of disease on CT = 91.0 − (0.65 × percent predicted diffusing capacity for carbon monoxide [DLCO]) − (0.53 × percent predicted FVC) + (0.34 × percent predicted FEV1). In group II, the CPI correlated more strongly with disease extent on CT (r2 = 0.51) than the individual pulmonary function test (DLCO the highest value, r2 = 0.38). A subanalysis demonstrated that the better fit of the CPI was ascribable to a correction of the confounding effects of emphysema. Mortality was predicted more accurately by the CPI than by a pulmonary function test in all clinical subgroups, including a separate cohort of 36 patients with histologically proven usual interstitial pneumonia (CPI, p < 0.0005; FVC, p = 0.002; PO2, p = 0.002). In conclusion, a new CPI, derived against CT and validated using split sample testing, is a more accurate prognostic determinant in usual interstitial pneumonia than an individual pulmonary function test.

Abstract Lymphangiomyomatosis (LAM) is characterized by the proliferation of abnormal smooth muscle cells and cystic degeneration of the lung. LAM affects almost exclusively young women. Although lung transplantation provides effective therapy for end-stage LAM, there are reports of LAM recurrence after lung transplantation. Whether these recurrent LAM cells arise from the patient or the lung transplant donor is an area of controversy. We used microsatellite marker fingerprinting and TSC2 gene mutational analysis to study a patient with recurrent LAM after single-lung transplantation. The DNA microsatellite marker pattern indicated the presence of patient-derived LAM cells in the allograft. A somatic one base pair deletion in exon 18 of the TSC2 gene was identified in pulmonary and lymph node LAM cells before transplantation. The same mutation was in the recurrent LAM, demonstrating that the recurrent LAM was derived from the patient. Fluorescence in situ hybridization revealed that cells immunoreactive with the monoclonal antibody HMB-45 did not contain a Y chromosome. These data indicate that histologically benign LAM cells can migrate or metastasize in vivo to the transplanted lung. In addition, the patient had no evidence of a renal angiomyolipoma at autopsy and therefore demonstrated for the first time that somatic TSC2 mutations cause LAM in patients without angiomyolipomas.

Abstract Acute lung injury (ALI) and its more severe form, the acute respiratory distress syndrome (ARDS), are syndromes of acute respiratory failure that result from acute pulmonary edema and inflammation. The development of ALI/ARDS is associated with several clinical disorders including direct pulmonary injury from pneumonia and aspiration as well as indirect pulmonary injury from trauma, sepsis, and other disorders such as acute pancreatitis and drug overdose. Although mortality from ALI/ARDS has decreased in the last decade, it remains high. Despite two major advances in treatment, low VT ventilation for ALI/ARDS and activated protein C for severe sepsis (the leading cause of ALI/ARDS), additional research is needed to develop specific treatments and improve understanding of the pathogenesis of these syndromes. The NHLBI convened a working group to develop specific recommendations for future ALI/ARDS research. Improved understanding of disease heterogeneity through use of evolving biologic, genomic, and genetic approaches should provide major new insights into pathogenesis of ALI. Cellular and molecular methods combined with animal and clinical studies should lead to further progress in the detection and treatment of this complex disease.

Purpose: To evaluate the role of adjuvant interferon alfa after complete resection of locally extensive renal cell carcinoma. Patients and Methods: A total of 283 eligible patients with pT3–4a and/or node-positive disease were randomly assigned after radical nephrectomy and lymphadenectomy to observation or to interferon alfa-NL (Wellferon, Burroughs-Wellcome, Research Park, NC) given daily for 5 days every 3 weeks for up to 12 cycles. Patients were stratified on the basis of pathologic stage. Patients remained on treatment until documented recurrence, excessive toxicity, or patient/physician preference deemed removal appropriate. Results: At median follow-up of 10.4 years, median survival was 7.4 years in the observation arm and 5.1 year in the treatment arm (log-rank P = .09). Median recurrence-free survival was 3.0 years in the observation arm and 2.2 years in the interferon arm (P = .33). Performance status (P = .003), nodal status (N2 v N0, P < .0001), and tumor stage (P = .0002) were significant prognostic factors in multivariate analysis. A proportional hazards model examining the effects of treatment arm and time to recurrence on survival after recurrence among patients who recurred found that random assignment to interferon treatment (P = .009) and shorter time to recurrence (P < .0001) were independent predictors of shorter survival after recurrence. Although no lethal toxicities were observed, severe (grade 4) toxicities including neutropenia, myalgia, fatigue, depression, and other neurologic toxicities occurred in 11.4% of those randomly assigned to interferon treatment. Conclusion: Adjuvant treatment with interferon did not contribute to survival or relapse-free survival in this group of patients.

Abstract Leukemia inhibitory factor (LIF) is a pleiotropic cytokine that induces cardiac myocyte hypertrophy through the signal transducing molecule, glycoprotein 130. To date, localization of LIF in the heart and regulation of cardiac LIF expression in congestive heart failure (CHF) remain undefined. The present study investigates the potential activation of LIF expression in the failing canine heart that was produced by progressive rapid ventricular pacing. Immunohistochemistry for LIF revealed that LIF immunoreactivity was present in the atrial and ventricular myocytes of the normal heart and was markedly increased in the failing heart as compared to the normal heart. Northern blot analysis demonstrated that cardiac LIF mRNA was increased in both atrium and ventricle in CHF as compared to the normal heart (P&lt;0.01). Linear regression analysis revealed a positive correlation between atrial LIF mRNA and atrial pressure (r=0.87, P&lt;0.001 in right atrium and r=0.86, P&lt;0.001 in left atrium). Positive correlations between left ventricular LIF mRNA and left ventricular dimensions (r=0.91, P&lt;0.0001 in end-systolic diameter; r=0.86, P&lt;0.001 in end-diastolic diameter), and an inverse correlation between left ventricular LIF mRNA and left ventricular ejection fraction (EF) were observed (r=−0.93, P&lt;0.0001). There was a positive correlation between left ventricular LIF mRNA and left ventricular mass index (LVMI) (r=0.85, P&lt;0.001). The present study demonstrates that cardiac LIF immunoreactivity and its gene expression are increased in a canine model of experimental CHF and suggests a potential role for LIF in the pathophysiology of CHF.

AbstractMultiple myeloma is a disseminated neoplasm of terminally differentiated plasma cells that is incurable with currently available therapies. Although the disease is radiosensitive, external beam radiation leads to significant toxicity due to sensitive end-organ damage. Thus, genetic approaches for therapy are required. We hypothesized that the incorporation of immunoglobulin promoter and enhancer elements in a self-inactivating (SIN) lentiviral vector should lead to specific and high-level transgene expression in myeloma cells. A SIN lentivector with enhanced green fluorescent protein (EGFP) expression under the control of a minimal immunoglobulin promoter as well as the Kappa light chain intronic and 3′ enhancers transduced myeloma cell lines with high efficiency (30%-90%). EGFP was expressed at a high level in myeloma cells but silent in all nonmyeloma cell lines tested compared with the cytomegalovirus (CMV) promoter/enhancer. Transduction of myeloma cells with the targeted vector coding for the human sodiumiodide symporter (hNIS) led to hNIS expression by these cells allowing them to concentrate radioiodine up to 18-fold compared with controls. Tumor xenografts in severe combined immunodeficiency mice expressing hNIS could be imaged using iodine-123 (123I) and shown to retain iodide for up to 48 hours. These tumor xenografts were completely eradicated by a single dose of the therapeutic isotope iodine-131 (131I) without evidence of recurrence up to 5 months after therapy. We conclude that lentivectors can be transcriptionally targeted for myeloma cells and the use of hNIS as a therapeutic gene for myeloma in combination with 131I needs further exploration.

▪ Abstract It has been a little more than 20 years since the first appreciation that the biologically active hormonal form of the secosteroid vitamin D—classically categorized as a regulator of calcium/phosphorous metabolism and bone mineralization—can exert effects on cells of the immune system. Since then a substantial literature has accumulated to suggest that these effects are exerted on multiple immune cell types, are predominantly suppressive at pharmacologic levels, and are potent enough to have true therapeutic potential in the management or prevention of immune-mediated diseases. Less clear at present, however, are the physiological roles played by the vitamin D endocrine system in the regulation of normal and abnormal immune responses. In this review, an appraisal of the current understanding of vitamin D–mediated immune regulation is presented that emphasizes progress towards its clinical application as well as the manner in which emerging models of normal immune function may facilitate a more complete understanding of its physiologic significance.

ABSTRACTWe examined the role of the cytokines gamma interferon (IFN-γ) and interleukin-12 (IL-12) in the model of acute babesiosis with the WA1Babesia. Mice genetically deficient in IFN-γ-mediated responses (IFNGR2KO mice) and IL-12-mediated responses (Stat4KO mice) were infected with the WA1Babesia, and observations were made on the course of infection and cytokine responses. Levels of IFN-γ and IL-12 in serum increased 24 h after parasite inoculation. The augmented susceptibility observed in IFNGR2KO and Stat-4KO mice suggests that the early IL-12- and IFN-γ-mediated responses are involved in protection against acute babesiosis. Resistance appears to correlate with an increase in nitric oxide (NO) production. In order to assess the contribution of different cell subsets to resistance against the parasite, we also studied mice lacking B cells, CD4+T cells, NK cells, and macrophages. Mice genetically deficient in B lymphocytes or CD4+T lymphocytes were able to mount protective responses comparable to those of immunosufficient mice. In contrast, in vivo depletion of macrophages or NK cells resulted in elevated susceptibility to the infection. Our observations suggest that a crucial part of the response that protects from the pathogenicBabesiaWA1 is mediated by macrophages and NK cells, probably through early production of IL-12 and IFN-γ, and induction of macrophage-derived effector molecules like NO.

ABSTRACTPneumocystis cariniiremains an important and potentially fatal cause of opportunistic pneumonia. Animal studies reveal that substantial quantities of surfactant protein D (SP-D) accumulate in the airspaces duringP. cariniipneumonia and are particularly abundant in aggregates of organisms. Due to the multimeric structure of SP-D, we hypothesized that SP-D mediates aggregation of the organism. From previous clinical studies it is known that aggregated organisms are conspicuous in sections of lung tissue and bronchoalveolar lavage (BAL) fluids of humans with activeP. cariniipneumonia. Herein, we observe that SP-D levels increased at least fourfold in BAL fluids of patients withP. cariniipneumonia. Next, a spectrophotometric sedimentation assay was developed to assess the aggregation ofP. cariniiin vitro by SP-D.P. cariniiorganisms were first stripped with glutathione to remove bound SP-D and subsequently incubated in the presence of SP-D and 2 mM calcium.P. cariniiincubated with natural SP-D (10 μg/ml) containing dodecamers and higher-order forms exhibited aggregation and enhanced sedimentation compared to that of glutathione-strippedP. carinii. Aggregation was also enhanced by the concentrated supernatant of rat BAL fluid, and this effect was abolished by the selective removal of SP-D from the lavage fluid.P. cariniiaggregation was reduced by maltose, mannose, and EDTA, consistent with the role of the SP-D C-type lectin domain (CRD) in the aggregation event. Comparisons of different molecular forms of SP-D showed that dodecamers—but not trimeric subunits—mediate optimal aggregation ofP. carinii. Aggregation ofP. cariniiby SP-D was shown to be responsible for the impaired phagocytosis of the organisms by alveolar macrophages. Thus, SP-D-mediated aggregation ofP. cariniimay represent one means by which the organism avoids elimination by the host.

Abstract Exocytosis of granules containing apoptosis-inducing proteins is one mechanism of target cell killing by cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells. Granules containing perforin and granzymes are redistributed to the area of cell contact initiated by specific interactions between surface ligands on a target cell and receptors on an effector lymphocyte. The formation of a stable conjugate between a cytotoxic lymphocyte and its potential target cell, followed by the directed delivery of granule components to the target cell are prerequisites of lymphocyte-mediated killing. Critical to understanding the development of cytotoxic function by CTLs and NK cells is the delineation of the second messenger pathways that specifically control the reorganization of the actin cytoskeleton during cell-mediated cytotoxicity. The low molecular weight guanosine 5′-triphosphate-binding proteins of the Rho family play a central role in these regulatory events controlling cytotoxic lymphocyte activation.