Activated CD8(+) T cells and NKT cells in BAL fluid improve diagnostic accuracy in sarcoidosis.

PURPOSE: The clinical diagnosis of pulmonary sarcoidosis is based on the presence of noncaseating granulomas in an appropriate clinical setting with either bilateral hilar adenopathy and/or parenchymal infiltrates. Lymphocytosis with an increased CD4/CD8 T cell ratio in bronchoalveolar lavage fluid is supportive. We evaluated the diagnostic accuracy of a predictive binary logistic regression model in sarcoidosis based on sex, age, and bronchoalveolar lavage fluid cell profile with and without the inclusion of HLA-DR(+) CD8(+) T cells and natural killer T-cell fractions. METHODS: A retrospective analysis of differential cell counts and lymphocyte phenotypes by flow cytometry in bronchoalveolar lavage was performed in 183 patients investigated for possible diffuse parenchymal lung disease. A logistic regression model with age, sex, lymphocyte fraction, eosinophils, and CD4/CD8 ratio in bronchoalveolar lavage fluid (basic model) was compared with a final model, which also included fractions of HLA-DR(+) CD8(+) T cells and natural killer T cells. Diagnostic accuracy of the two models was assessed by receiver operating characteristic (ROC) curves. RESULTS: The area under the ROC curve for the basic and final model was 0.898 [95 % confidence interval (CI) 0.852-0.945] and 0.937 (95 % CI 0.902-0.972), respectively, p = 0.008. CONCLUSIONS: Assessment of HLA-DR(+) CD8(+) T cell and natural killer T-cell fractions may improve diagnostic accuracy and further strengthen the importance of bronchoalveolar lavage in the diagnostic workup of sarcoidosis.

Elevated serum concentrations of activated hepatocyte growth factor activator in patients with multiple myeloma.

OBJECTIVES: Hepatocyte growth factor (HGF) is a potential key factor in multiple myeloma. Conversion of pro-HGF to its active form is a critical limiting step for its biological effects. We aimed to examine the levels of the most potent activator, the hepatocyte growth factor activator (HGFA), in serum and bone marrow plasma of patients with multiple myeloma. METHODS: The activated form of HGFA was measured by an enzyme-linked immunosorbent assay in serum (n = 49) and bone marrow plasma (n = 16) from multiple myeloma patients, and in serum from healthy controls (n = 24). RESULTS: The median concentrations of activated HGFA in myeloma and control sera were 39.7 (range 6.2-450.0) and 17.6 ng/mL (range 4.8-280.6), respectively. The difference was statistically significant (P = 0.037). The median concentration of activated HGFA in bone marrow plasma was 6.1 ng/mL (range 3.5-30.0). CONCLUSION: We here show for the first time that the activated form of HGFA is present at high levels in serum and bone marrow of myeloma patients, thus providing a necessary prerequisite for the activation of HGF.

Toll-like receptors mediate proliferation and survival of multiple myeloma cells.

Multiple myeloma (MM) is an incurable B-cell malignancy characterized by accumulation of malignant plasma cells in bone marrow (BM) and recurrent or persistent infections. Toll-like receptors (TLRs) are essential in the host defense against infections and today 10 human TLRs (TLR1-TLR10) and one TLR-homolog (RP105) have been characterized. B cells express several TLRs (mainly TLR1, 6, 7, 9, 10 and RP105) and TLR-initiated responses in B cells include proliferation, anti-apoptosis effect and plasma cell (PC) differentiation. The present study was designed to analyze the role of TLRs in MM. We show that frequent expressions of TLRs were detected in cell lines from MM patients (minimum six TLRs in each). In comparison, only few TLRs (mainly TLR1 and or RP105) were found expressed in PCs from BM of healthy donors. In addition, TLR-specific ligands induce increased proliferation and survival of the MM cell lines, partially due to an autocrine interleukin-6 production. Importantly, we demonstrate that also PC from MM patients proliferates in response to TLR-specific ligands. In conclusion, TLR-ligands may contribute to increased growth and survival of MM cells in MM patients.

Identification of new targets for therapy of osteolytic bone disease in multiple myeloma.

One of the most characteristic features of multiple myeloma is the development of osteolytic bone lesions. Myeloma-associated bone disease is caused by an increase in osteoclastic bone resorption and a decrease in osteoblastic new bone formation. Insight into the molecular mechanisms of osteoclastogenesis has been provided by the detection of receptor activator of NF-kappaB ligand (RANKL), its specific receptor (RANK) and its decoy receptor antagonist osteoprotegerin (OPG). The RANK signaling system is abnormally regulated in multiple myeloma and targeting this system may ameliorate myeloma bone disease. Less is known about the development of osteoblastic dysfunction, and further knowledge about the interaction between myeloma cells and osteoblasts is required. The aim of this review is to focus on the principles of bone biology for a better understanding of the development of myeloma bone disease and to identify possible therapeutic targets.

Activated CD8+ T cells and natural killer T cells in bronchoalveolar lavage fluid in hypersensitivity pneumonitis and sarcoidosis.

BACKGROUND: Sarcoidosis and hypersensitivity pneumonitis are diffuse parenchymal lung diseases characterized by formation of non-caseating granulomas with a bronchocentric distribution. Analysis of the white blood cell differential profile in bronchoalveolar lavage fluid can be a useful supplement in the diagnostic work-up. OBJECTIVE: Diagnostic markers that can improve the discrimination of sarcoidosis and hypersensitivity pneumonitis are wanted. METHODS: Bronchoalveolar lavage fluid fractions of CD4+ and CD8+ T cells expressing the activation marker HLA-DR and fractions of natural killer T cells determined by flow cytometry were investigated in sarcoidosis (N=83), hypersensitivity pneumonitis (N=10) and healthy control subjects (N=15). RESULTS: In hypersensitivity pneumonitis, natural killer T cell fractions were over 7-fold greater [median (IQR): 5.5% (3.5-8.1) versus 0.7% (0.5-1.2), p<0.0001], and HLA-DR+ fractions of CD8+ lymphocytes were almost two fold greater [median (IQR): 79% (75-82) versus 43% (34-52), p<0.0001] than in sarcoidosis. In healthy control subjects, natural killer T cell fractions of leucocytes and HLA-DR+ fractions of CD8+ lymphocytes were lower [median (IQR): 0.3% (0.3-0.6) and 30% (26-34), p=0.02 and p=0.01 compared to sarcoidosis]. The combined use of these two markers seems to discriminate the diseases very well. CONCLUSION: This study suggests a role for the bronchoalveolar lavage fluid lymphocyte subsets HLA-DR+ CD8+ T cells and natural killer T cells in the diagnostic work up of sarcoidosis and hypersensitivity pneumonitis.

Marked osteoblastopenia and reduced bone formation in a model of multiple myeloma bone disease in severe combined immunodeficiency mice.

We report on an in vivo model of human myeloma producing bone disease in irradiated severe combined immunodeficiency disease mice using the human myeloma cell line JJN-3 and its subline JJN-3 T1. The cell lines are not Epstein-Barr virus transformed and produce large amounts of hepatocyte growth factor (HGF). Mice had radiological signs of osteolysis and mild hypercalcemia. Xenografted cells were predominantly found in bone marrow and brown adipose tissue, but also in meninges and liver. Take was documented by histopathological examination, immunophenotyping of cultured bone marrow, and radiography. HGF was detected in serum and bone marrow plasma. Disease generally occurred within 45 days of intravenous inoculation and was signaled by paraparesis or signs of intracranial neoplasia. More than 90% of the mice had take of xenografts. The subline JJN-3 T1 gave more reproducible bone marrow take than the native cell line. Bone histomorphometric examination revealed a 99% reduction in osteoblast counts and a 33% reduction in osteoclast counts in areas of tumor growth. Bone formation rates were reduced by 53%. The results suggest that osteoblastopenia and reduced bone formation is of importance for the occurrence of osteolytic lesions in this model.

Hepatocyte growth factor reverses the TGF-beta-induced growth inhibition of CCL-64 cells. A novel bioassay for HGF and implications for the TGF-beta bioassay.

The influence of human hepatocyte growth factor (HGF) on the transforming growth factor beta (TGF-beta) bioassay CCL-64 was examined. HGF induced proliferation of the CCL-64 cells and potently counteracted TGF-beta-induced growth inhibition. HGF was not inactivated by transient acidification to pH 2, a commonly used procedure to activate latent TGF-beta. HGF was a stronger mitogen for the mink lung cells than epidermal growth factor (EGF), a known stimulator of CCL-64 cell growth. Costimulation of the cells by these two cytokines resulted in an additive effect on proliferation. In complex biological fluids containing large amounts of HGF, the TGF-beta concentration can be underestimated when determined by the CCL-64 assay. When a fixed amount of TGF-beta is added, the CCL-64 cells can be used as a reliable bioassay for HGF with a sensitivity of about 1 ng/ml.

Comparison of the effects of 2-chlorodeoxyadenosine and melphalan myeloma cell lines.

We have studied the effects of 2-chlorodeoxyadenosine (2-CdA) and melphalan on DNA synthesis and cell proliferation of five myeloma cell lines and one primary culture of highly purified myeloma cells. The DNA synthesis was estimated by thymidine incorporation and cell death was estimated by a coluorimetric assay sensitive to mitochondrial activity. The concentrations of 2-CdA giving 50% inhibition of DNA synthesis (ID50) in four cell lines were 8, 100, 500 and 2500 nM, whereas the corresponding concentrations of melphalan were 600, 600, 1000 and 7500 nM, respectively. In one cell line, the ID50 for melphalan was 400 nM, whereas 2-CdA apparently was without inhibitory effect and the ID50 was not reached. The ID50 for 2-CdA in the primary culture was 250 nM. When compared on a molar basis, 2-CdA had a more potent inhibitory effect than melphalan on four out of five myeloma cell lines. This is in contrast to clinical experiments which have shown lack of effect of 2-CdA in myeloma patients. Our study shows that 2-CdA has a marked heterogeneous effect on myeloma cell lines and opens up the possibility that a similar variation in sensitivity may also exist among myeloma cell clones in vivo.

The role of hepatocyte growth factor and its receptor c-Met in multiple myeloma and other blood malignancies.

The cytokine hepatocyte growth factor (HGF) and its receptor c-Met are a ligand-receptor pair with important functions in a communicative interplay between HGF-producing, mesenchymal cells and c-Met-expressing target cells. HGF is cytoprotective and causes regeneration of parenchyma after tissue damage in several organs. The receptor c-Met was first characterized as an oncogene product being responsible for the transformation of an osteosarcoma cell line. HGF or c-Met is overexpressed in several human cancers, including various carcinomas. Some cells of hematopoietic origin also seem to be capable of c-Met expression, but the precise role of HGF in normal hematopoiesis is yet to be determined. In blood malignancies like acute myelogenous leukemia and, notably, multiple myeloma, HGF is overproduced and has implications for the prognosis of the patients. Biological significance of HGF overexpression in multiple myeloma is discussed and is likely to include effects on bone turnover and angiogenesis.

Matrix metalloproteinases in multiple myeloma.

Multiple myeloma is a deadly malignancy characterized by plasma cell infiltration of bones. The resulting effect is painful "punched-out" lesions where bone is eroded and filled with myeloma cells that suppress and replace the normal marrow components. Recently it has been shown that myeloma cells produce matrix-metalloproteinase-9 (MMP-9) and MMP-2 and that accumulation of MMP-9 protein is suppressed upon expression of the heparan sulfate proteoglycan, syndecan-1. In this review, we briefly consider the potential roles for MMPs in the pathogenesis of multiple myeloma. MMPs likely have major roles in: 1) the infiltration of bone and other tissues by the myeloma cells; 2) the osteolytic bone destruction caused by overly active osteoclasts, 3) extracellular matrix remodeling by bone marrow stromal cells; 4) promoting the invasion of the endothelial cells that form neoangiogenic blood vessels necessary to sustain tumor foci; and 5) promoting the growth of myeloma cells. Effective and safe synthetic inhibitors of MMPs are available and these may prove useful in limiting the growth and spread of myeloma cells. In addition, recent insights into the suppression of MMP-9 by syndecan-1 may suggest new strategies for treatment of myeloma.

Elevated hepatocyte growth factor in sera from patients with insulin-dependent diabetes mellitus.

Hepatocyte growth factor (HGF) is a pleiotropic cytokine known to be involved in tissue regeneration and repair. We measured serum levels of HGF in patients with insulin-dependent diabetes mellitus (type 1). The patients were divided into four groups: (1) 10 patients at clinical presentation before insulin treatment; (2) 19 patients with newly diagnosed type 1 diabetes (diabetes duration 1/2-3 years); (3) 14 patients with long-standing type 1 diabetes without renal involvement (diabetes duration >10 years, and urinary albumin excretion (UAER) <20 microg/ min); and (4) 20 patients with long-standing type I diabetes with renal involvement (diabetes duration >10 years and UAER 20-500 microg/min). Sera from 24 age- and sex-matched healthy blood donors constituted a control group. The HGF levels of the four groups were (mean +/- SD); group 1, 0.74+/-0.14; group 2, 0.78+/-0.40; group 3, 0.86+/-0.42; group 4, 0.79+/-0.27 ng/ml, compared to 0.43+/-0.24 ng/ml in the control group (P<0.0008). HGF levels were not significantly different between the four patient groups. The elevated serum HGF levels did not correlate with complications related to type 1 diabetes, such as UAER, retinopathy and macrovascular complications, suggesting that HGF levels were not associated with the type 1 diabetes complications. In conclusion, our results show that type 1 diabetic patients have increased serum HGF levels compared with controls and that HGF is elevated to the same extent in newly diagnosed as well as in long-standing type 1 diabetes.

Role of hepatocyte growth factor and its receptor c-met in multiple myeloma.

Multiple myeloma is characterised by the clonal expansion of malignant plasma cells. Recently, we reported that a new cytokine, hepatocyte growth factor (HGF), and its receptor c-met are related to this disease. Here we review the observations that associate HGF with myeloma. Malignant plasma cells produce HGF and express the receptor c-met. Many patients have elevated HGF levels, which is unfavourable both in terms of survival and response to treatment. Possible biological roles of HGF in this disease are discussed, with special focus on bone homeostasis and its binding to heparan sulphate proteoglycans.

Bone morphogenetic proteins induce apoptosis in multiple myeloma cells by Smad-dependent repression of MYC.

Bone morphogenetic proteins (BMPs) have been shown to induce apoptosis and growth arrest in myeloma cells. However, the molecular mechanisms behind these events are not known. The MYC oncogene is a master regulator of cell growth and protein synthesis and MYC overexpression has been proposed to be associated with the progression of multiple myeloma. Here, we show that BMP-induced apoptosis in myeloma cells is dependent on downregulation of MYC. Moreover, the results suggest that targeting the MYC addiction in multiple myeloma is an efficient way of killing a majority of primary myeloma clones. We also found that myeloma cells harboring immunoglobulin (IG)-MYC translocations evaded BMP-induced apoptosis, suggesting a novel way for myeloma cells to overcome potential tumor suppression by BMPs.

Serum/glucocorticoid-regulated kinase 1 (SGK1) is a prominent target gene of the transcriptional response to cytokines in multiple myeloma and supports the growth of myeloma cells.

Multiple myeloma (MM) is a paradigm for a malignant disease that exploits external stimuli of the microenvironment for growth and survival. A thorough understanding of the complex interactions between malignant plasma cells and their surrounding requires a detailed analysis of the transcriptional response of myeloma cells to environmental signals. We determined the changes in gene expression induced by interleukin (IL)-6, tumor necrosis factor-α, IL-21 or co-culture with bone marrow stromal cells in myeloma cell lines. Among a limited set of genes that were consistently activated in response to growth factors, a prominent transcriptional target of cytokine-induced signaling in myeloma cells was the gene encoding the serine/threonine kinase serum/glucocorticoid-regulated kinase 1 (SGK1), which is a down-stream effector of PI3-kinase. We could demonstrate a rapid, strong and sustained induction of SGK1 in the cell lines INA-6, ANBL-6, IH-1, OH-2 and MM.1S as well as in primary myeloma cells. Pharmacologic inhibition of the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway abolished STAT3 phosphorylation and SGK1 induction. In addition, small hairpin RNA (shRNA)-mediated knock-down of STAT3 reduced basal and induced SGK1 levels. Furthermore, downregulation of SGK1 by shRNAs resulted in decreased proliferation of myeloma cell lines and reduced cell numbers. On the molecular level, this was reflected by the induction of cell cycle inhibitory genes, for example, CDKNA1/p21, whereas positively acting factors such as CDK6 and RBL2/p130 were downregulated. Our results indicate that SGK1 is a highly cytokine-responsive gene in myeloma cells promoting their malignant growth.

Syndecan-1 in B lymphoid malignancies.

Syndecans are heparan sulfate-bearing proteoglycans that are found on the surface of most cells. Syndecan-1 is expressed predominantly on epithelia, but is also present on pre-B cells and plasma cells. The syndecans act to bind various effector molecules via their heparan sulfate chains, including both soluble and insoluble molecules within the extracellular milieu. These interactions promote cell adhesion to extracellular matrix and to adjacent cells. In addition, the syndecans can bind to and affect the biological activity of a number of heparin-binding growth factors. Thus, syndecan-1 can play a dramatic role in regulating cell behavior. In this review we discuss the expression of syndecan-1 on malignant B lymphoid cells as well as specific structure-function relationships of the molecule. Emphasis is placed on the important role that syndecan-1 has in regulating the growth of B lymphoid malignancies, particularly multiple myeloma.

Mobility, survival and nursing-home requirements after hip fracture.

A consecutive series of 117 patients treated for hip fracture were followed up prospectively for three years. The mortality was highest during the first year. The proportion living in nursing-homes was increased by 50% at one year and 25% at three years compared with before injury, but the absolute numbers were reduced because of mortality. Reduced pre-injury mobility greatly increased the risk of becoming institutionalized. The proportion of the survivors who walked without aids was reduced by more than half at one and three years. The proportion of those bedridden increased six fold. Among patients who walked without aids before fracture 31% needed two sticks or more and 7% were bedridden after one year. Among those who before fracture walked with one stick or more, the percentages were 91 and 43.

Preoperative traction in patients with hip fractures.

A series of 80 patients with cervical, trochanteric or subtrochanteric hip fractures were randomized to either treatment without traction, skin traction, or skeletal traction during the 1883 h between admission and operation. The institution of skin or skeletal traction was not particularly painful for the patient, but we found no indication that either was of discernible benefit. The number of analgesic medications needed was no higher in patients without traction. We conclude that traction should not be administered routinely to patients awaiting operation for hip fracture.

TNF and IL-6 are potent growth factors for OH-2, a novel human myeloma cell line.

A novel human myeloma cell line, OH-2, was established from pleural fluid of a myeloma patient in end stage of the disease. Effects of cytokines on proliferation were analyzed by measuring uptake of 3H-thymidine. Cell surface antigens were detected by flow cytometry. The cell line is dependent on IL-6 for growth and proliferates in response to TNF. There is synergy between the stimulatory response of TNF and IL-6. The cells express both the p55 and p75 TNF receptors. Neutralizing anti-IL-6 did not inhibit TNF-mediated proliferation, showing that TNF acts through a pathway that is independent of IL-6. TNF was more potent than IL-6 in stimulating the growth of primary myeloma cultures (> 99% pure) from the same patient (OH-2-PC), indicating that TNF in selected myeloma patients has a growth-promoting effect equal to IL-6. OH-2 cells produce and secrete monoclonal IgG-kappa.

Interleukin-15 blocks apoptosis and induces proliferation of the human myeloma cell line OH-2 and freshly isolated myeloma cells.

The growth factor-dependent myeloma cell line OH-2, which has previously been shown to be responsive to interleukin (IL)-6, tumour necrosis factor (TNF)-alpha and lymphotoxin, was examined for response to other growth factors. Enhanced proliferation was found in the presence of IL-10, IL-15, IL-2 and insulin growth factor (IGF)-1. Proliferation was strongest in response to IL-6, intermediate and roughly equipotent in response to IL-15, IL-10 and TNF-alpha, and modest in response to IL-2 and IGF-1. IL-15 was synergistic with TNF-alpha, whereas combinations of IL-15 and the other cytokines were merely additive. IL-15-induced proliferation could not be blocked by neutralizing antibody against gp 130, the common transducer chain of IL-6 and related cytokines. IL-15 and IL-6 prevented apoptosis equally well, both better than TNF-alpha, IL-10, and IGF-1. In four out of six samples of purified primary cells, IL-15 and IL-6 induced proliferation. Furthermore, IL-15 mRNA was detected by RT-PCR in most myeloma cell lines and freshly isolated purified patient samples. IL-15 protein was detectable only in one out of about 20 tested cell supernatants from patients and myeloma cell lines. The OH-2 cell line is multi-responsive to cytokines and is a good system for the study of integration of cytokine signal transduction and growth control in myeloma. IL-15 represents a novel modality of growth regulation in myeloma.

The role of the two TNF receptors in proliferation, NF-kappa B activation and discrimination between TNF and LT alpha signalling in the human myeloma cell line OH-2.

We wanted to study the role of the two TNF receptors (TNFR) in mediating proliferation and nuclear transcription factor kappa-B (NF-kappa B) activation in the human myeloma cell line OH-2. Agonistic antibodies to either of the TNFRs were able to induce proliferation in OH-2 cells, while only antibodies to the p55 TNFR could activate the NF-kappa B. TNF was 100-1000-fold more potent than LT alpha in activation of NF-kappa B and in induction of proliferation in OH-2 cells. Only a 2-fold difference between TNF and LT alpha in affinity for the TNFRs was detected, indicating that the difference in the specific activities of the cytokines can not be explained by different binding affinities. Antagonistic mAbs to either the p55 or p75 TNFR blocked the binding of both cytokines to the cells and significantly inhibited proliferation induced by TNF. On the other hand, only the p55 TNFR mAb was capable of inhibiting the proliferative effect of LT alpha. The p55 mAb 44E potentiated the proliferation induced by LT alpha, but did not affect the TNF-mediated proliferation. The data lead to the following conclusions: (1) both TNFR species trigger proliferation of OH-2 cells, whereas only the p55 TNFR activates the NF-kappa B; (2) TNF signals through both TNFR, whereas LT alpha mediates its signal through the p55 TNFR only; (3) activation of the p55 TNFR by LT alpha is not optimal, but can be facilitated by co-stimulating the receptor with the mAb 44E.