Real-time ultrasound elastography for assessment of response to brentuximab vedotin treatment in relapsed and refractory Hodgkin lymphoma.

OBJECTIVE: To evaluate the application of ultrasound elastography (ES) in monitoring treatment response to brentuximab vedotin (Seattle Genetics, Seattle, WA, USA). PATIENTS AND METHODS: Patients were selected when suffering from relapsed and refractory Hodgkin Lymphoma (HL). Our research investigated if the interim of ultrasound ES is a predictive value for treatment outcome in patients treated with brentuximab vedotin. RESULTS: 30 patients with refractory HL were enrolled. After treatment with brentuximab vedotin, 14 patients were classified as responders and 16 were classified as non-responders. At baseline, there was no difference between the groups both in the strain ratio (z = 1.1, p = 0.3) and in the volume (z = -0.3, p = 0.8). While after treatment there was a difference between the groups both in the strain ratio (z = -2.09, p < 0.05) and in the volume (z = 4.1, p < 0.001). CONCLUSIONS: Real-time elastosonography could be a reliable tool for the assessment of refractory Hodgkin lymphoma response to brentuximab vedotin treatment and help to identify patient with improved clinical outcome early during treatment. Results indicate that changes in ultrasound elastosonography parameters are correlated with the clinical and pathologic response of patients. These findings could pave the way for establishing protocols for the clinical applications of ultrasound elastography techniques in therapy response monitoring.

The role of second-look ultrasound of BIRADS-3 mammary lesions detected by breast MR imaging.

OBJECTIVE: To asses the value of second-look ultrasound (US) for identifying BIRADS 3 (Breast Imaging Reporting Data System) mammary lesions detected by breast Magnetic Resonance imaging (MRI). MATERIALS AND METHODS: From April 2008 to May 2009 330 breast MRI were performed of which 60 patients are classified as BIRADS 3. 84 lesions underwent second-look US and percutaneous vacuum biopsy Vacora system US-guided. STATISTICAL ANALYSIS: lesions were stratified into two groups: visible on US (Group 1) and not visible on US (Group 2). The clinical impact of second-look US was studied in terms of negative predictive value (NPV). RESULTS: The positive predictive value (PPV) of category 3 BIRADS MRI was found to be 89%. Second look-US results detected lesions in 51% of the MRI enhancing lesions. The second look-US showed a NPV of 97%. The NPV of second look-US was significantly greater than the NPV of MRI BIRADS 3 (97% vs 89%, p<0.05). The logistic regression analysis showed a higher number of malignant lesions in group 1 than in group 2 (7vs 2, OR 3.7, p<0.05). CONCLUSIONS: The second-look US permitted the correct management of subcentimetric MRI BIRADS 3 lesions not visible with conventional imaging tecniques.

Role of [18F]-FDG-PET/MDCT in evaluating early response in patients with Hodgkin's lymphoma.

PURPOSE: The authors evaluated the prognostic role of 18-fluoro-fluorodeoxyglucose positron emission tomography/multidetector computed tomography ([(18)F]-FDG PET/MDCT) in treating patients with Hodgkin's lymphoma (HL). MATERIALS AND METHODS: We retrospectively evaluated 132 patients with HL studied with PET/MDCT before the start of chemotherapy (CTX) for staging purposes and again after two CTX cycles with [doxorubicin (Adriblastin), bleomycin, vinblastine, dacarbazine (ABVD_] (interim PET/MDCT), at least 30 days after the end of the last CTX cycle and/or 3 months after the end of radiotherapy, if delivered (final PET-MDCT). RESULTS: Interim PET-MDCT was negative in 104/132 patients (79%), and their final PET-MDCT showed complete remission in 102/104 (98%) of cases, with disease recurrence/persistence in two (2%). In the remaining 28 (21%) patients, interim PET-MDCT revealed an early response in 68% of cases and chemoresistance with disease progression in 32% of cases; in these 28 patients, final PET-MDCT showed a lack of response to treatment in 43% of cases (43%) and complete remission in 57% of cases. Statistical analysis of these data showed that interim PET-MDCT had a negative predictive value of 98% and a positive predictive value of 42%, with values of sensitivity, specificity and diagnostic accuracy of 85.7%, 86.4% and 86.4%, respectively. CONCLUSIONS: Interim PET-MDCT has a reliable prognostic role in diagnosis and treatment of patients with HL, as it helps predict which patients are more likely to achieve a complete response at the end of treatment. PET/MDCT may also lead to a change in treatment, with reduced treatment-related toxic effects and significantly reduced total costs.

Portal vein thrombosis after radiofrequency ablation of HCC.

The authors describe an unusual complication after radiofrequency ablation of hepatocellular carcinoma (HCC). An 84-year old man, already operated of right hepatectomy for HCC, underwent radiofrequency ablation (RFA) of a new focal hepatic lesion in IV segment, under ultrasound (US) and computed tomography (CT) guidance. The procedure was carried out without any special difficulties or complications. Seven days later, the patient suddenly complained epigastric pain, progressive jaundice and sleepiness and an increase in cholestasis sierological parameters. A CT scan revealed thrombosis of the left side branch of the portal vein, with moderate bile ducts distension. The case described demonstrates how RFA may cause thermally mediated damage of the surrounding structures, due to unpredictable radio-frequency propagation. The interest of this case report is due to the fact that portal vein thrombosis did not occur immediately after the procedure, it happened without direct vessel injury by the needle and involved a vessel greater than 3 mm.

Accuracy of early and delayed FDG PET-CT and of contrast-enhanced CT in the evaluation of lung nodules: a preliminary study on 30 patients.

PURPOSE: The aim of our prospective study was to compare the diagnostic accuracy of early, delayed and dual-time-point positron emission tomography (PET) acquisition with contrast enhanced computed tomography (CT) within a PET-CT examination in the evaluation of pulmonary solitary nodules (SPNs). MATERIALS AND METHODS: Thirty patients were enrolled in the study. All the patients underwent a dual-time-point PET-CT examination. Whole-body PET images were acquired at 50 min after fluorine18-fluorodeoxyglucose ((18)F-FDG) administration (early), followed by a chest acquisition (delayed). Lung nodules with maximum standardised uptake value SUVmax > or =2.5 were considered malignant. SUVmax was calculated on early and delayed images; SUV increasing > or =10% (Delta SUVmax) was considered suggestive of malignancy. Absence of significant lung nodule enhancement (<15 Delta HU) at CT was considered strongly predictive of benignity. For the CT morphological assessment, the irregularity of the shape of each lesion was rated. PET-CT results were related to histological assays and clinical records. Diagnostic accuracy was assessed by area under the receiveroperarting characteristic (ROC) curves analysis. RESULTS: Early and delayed SUVmax of malignant nodules were significantly higher than those of benign disease. Early SUVmax sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 77%, 91%, 79.5% and 66.7%; delayed SUVmax corresponding values were 77%, 66%, 74% and 66%; dual-time-point SUVmax values were 83%, 67%, 75% and 74%; DeltaHU values were 94%, 34%, 67%, 96%; CT morphologic evaluation values were 61%, 46%, 60%, 47%. Area under the curve (AUC) for early SUVmax was 0.79, for delayed SUVmax 0.80, for dual-time-point SUVmax 0.85, for DeltaHU 0.63 and for CT morphologic assessment 0.58. CONCLUSIONS: In our small series of patients, early and delayed SUVmax showed comparable accuracies, whereas morphological and contrast enhanced CT evaluations showed the lowest accuracies. Dual-time-point SUVmax showed the largest AUC. However, dual-time-point SUVmax was most sensitive, whereas single-time-point SUVmax was most specific.

Cost-effectiveness analysis of two vacuum-assisted breast biopsy systems: Mammotome and Vacora.

PURPOSE: This study was undertaken to compare the cost effectiveness of two vacuum-assisted breast biopsy devices, the Mammotome and Vacora systems. MATERIALS AND METHODS: Between January and June 2006, 238 vacuum-assisted breast biopsies were performed at our radiology department. Five out of 238 lesions were excluded because of inadequate sampling. The Mammotome system was used in 108/233 lesions and the Vacora system in 125/233. Fifty-eight lesions underwent ultrasound-guided breast biopsy, and 50 lesions underwent mammography-guided biopsy with both Mammotome and Vacora devices. Magnetic-resonance-guided biopsy was possible with the Vacora system only (17/125 lesions). RESULTS: All procedures were successfully completed. No significant differences were found between the results of the Mammotome and Vacora biopsies in terms of effectiveness: sensitivity was 84.4% and 86.2%, respectively, and specificity 100%. In terms of cost, the Mammotome system has higher costs per procedure compared with the Vacora. CONCLUSIONS: Our clinical results confirm the diagnostic accuracy of both the Mammotome and Vacora systems, whereas our cost analysis shows that there is a considerable difference, mostly related to the initial investment.

MR imaging-guided 10-gauge vacuum-assisted breast biopsy: histological characterisation.

PURPOSE: The aim of this study was to evaluate a handheld vacuum-assisted device for magnetic resonance imaging (MRI)-guided breast biopsy. MATERIALS AND METHODS: In 47 patients, a total of 47 suspicious breast lesions (mean maximum diameter 9 mm) seen with MRI (no suspicious changes on breast ultrasound or mammography) were sampled using a 10-gauge vacuum-assisted breast biopsy (VAB) device under MRI guidance. Histology of biopsy specimens was compared with final histology after surgery or with follow-up in benign lesions. RESULTS: Technical success was achieved in all biopsies. Histological results from VAB revealed malignancy in 15 lesions (32%), atypical ductal hyperplasia in four lesions (8%) and benign findings in 28 lesions (60%). One of four lesions with atypical ductal hyperplasia was upgraded to ductal carcinoma in situ after surgery. One of seven lesions showing ductal carcinoma was upgraded to invasive carcinoma after surgery. Two lesions diagnosed as infiltrating carcinoma by VAB were not validated at excisional biopsy due to complete removal of the lesion during the procedure. During the follow-up (mean 18 months) of histologically benign lesions, we observed no cases of breast cancer development. Because of morphological changes on follow-up MRI scans, two lesions underwent surgical excision, which confirmed their benign nature. Besides minor complications (massive bleeding, n = 1) requiring no further therapeutic intervention, no complications occurred. CONCLUSIONS: MRI-guided biopsy of breast lesions using a handheld vacuum-assisted device is a safe and effective method for the workup of suspicious lesions seen on breast MRI alone.

MR breast imaging: a comparative analysis of conventional and parallel imaging acquisition.

PURPOSE: The objective of this study was to compare conventional breast magnetic resonance imaging (MRI) with breast MRI acquired with the sensitivity-encoding (SENSE) technique on a 1.5-T MRI scanner in the same patient, on the basis of image quality and kinetics analysis. MATERIALS AND METHODS: Thirty-one patients with suspicious mammography and US findings were included in the study. Conventional breast MRI consisted of the following sequences: T1 (matrix, 288 x 512); T2 (matrix 225 x 512); short tau inversion recovery (STIR) (matrix 320 x 224) and dynamic T1 [2D fast-field echo (FFE)] (matrix 256 x 512; temporal resolution

In vivo, high-field, 3-Tesla 1H MR spectroscopic assessment of liver fibrosis in HCV-correlated chronic liver disease.

PURPOSE: Histology is the gold standard by which to diagnose and score hepatic fibrosis. Recently, it has been proposed that hepatic magnetic resonance spectroscopy (MRS) could provide an accurate representation of the disease process. The aim of this study was to correlate the in vivo high-field (3-Tesla) (1)H MRS features of noncirrhotic chronic hepatitis C patients stratified according to the histopathological stages of fibrosis. MATERIALS AND METHOD: Six healthy controls and 23 patients with biopsy-proven precirrhotic hepatitic C virus (HCV)-related liver disease were included. The subdivision of patients into the histopathological stages of fibrosis was based on the Ishak fibrosis (F) scoring system: mild hepatitis (0< or =F< or =1), moderate (2< or =F< or =3) and severe hepatitis (4< or =F< or =5). For correlation analysis, the Spearman nonparametric test was used. Differences between groups were calculated with the nonparametric Mann-Whitney U test. A p value <0.05 was considered significant. The particular metabolite content was evaluated in relative units (RU), according to the pattern metabolite/H(2)O=area of the metabolite x1,000/area of nonsuppressed water. RESULT: A significant statistical difference was observed between control vs. mild and moderate vs. severe disease severity in choline-containing compounds (CCC)/H(2)O ratios (p=0.0379 and p=0.0003) and in glutamine/glutamate (Glx)/H(2)O ratios (p=0.004 and p<0.0001), whereas a statistically significant difference in the lipid/H(2)O ratios was achieved only between control vs. moderate and between moderate vs. severe stages of disease (p=0.011 and p=0.0030). CONCLUSION: High-field (1)H MRS successfully differentiates between mild/moderate vs. severe stages of chronic hepatitis and can be considered a complement to most standard imaging protocols in the liver.

Sixty-four-section CT cerebral perfusion evaluation in patients with carotid artery stenosis before and after stenting with a cerebral protection device.

BACKGROUND AND PURPOSE: Brain tissue viability depends on cerebral blood flow (CBF) that has to be kept within a narrow range to avoid the risk of developing ischemia. The aim of the study was to evaluate by 64-section CT (VCT) the cerebral perfusion modifications in patients with severe carotid stenosis before and after undergoing carotid artery stent placement (CAS) with a cerebral protection system. MATERIALS AND METHODS: Fifteen patients with unilateral internal carotid stenosis (>or=70%) underwent brain perfusional VCT (PVCT) 5 days before and 1 week after the stent-placement procedure. CBF and mean transit time (MTT) values were measured. RESULTS: Decreased CBF and increased MTT values were observed in the cerebral areas supplied by the stenotic artery as compared with the areas supplied by the contralateral patent artery (P < .001). A significant normalization of the perfusion parameters was observed after the stent-placement procedure (mean pretreatment MTT value, 5.3 +/- 0.2; mean posttreatment MTT value, 4.3 +/- 0.18, P < .001; mean pretreatment CBF value, 41.2 mL/s +/- 2.1; mean posttreatment CBF value, 47.9 mL/s +/- 2.9, P < .001). CONCLUSIONS: PVCT is a useful technique for the assessment of the hemodynamic modifications in patients with severe carotid stenosis. The quantitative evaluation of cerebral perfusion makes it a reliable tool for the follow-up of patients who undergo CAS.

FEM analysis of RF breast ablation: multiprobe versus cool-tip electrode.

BACKGROUND: Radio-frequency ablation (RFA) has recently received much attention as an effective minimally invasive strategy for the local treatment of tumors. The purpose of this study was to evaluate the efficacy of single-needle cool-tip RF breast ablation in terms of temperature distribution and duration of the procedure as compared to multiprobe RF breast ablation. MATERIALS AND METHODS: Two different commercially available radiofrequency ablation needle electrodes were compared. Finite-element method (FEM) models were developed to simulate the thermoablation procedures. A series of ex vivo radiofrequency thermal lesions were induced to check the response of the FEM calculations. RESULTS: Data obtained from FEM models and from ex vivo procedures showed that cool-tip RF breast ablation assures better performances than multiprobe RF breast ablation in terms of temperature distribution and duration of the procedure. Histopathological analysis of the cool-tip RF thermoablated specimens showed successful induction of coagulation necrosis in the thermoablated specimens. CONCLUSION: Data obtained from FEM models and from ex vivo procedures suggest that the proposed cool-tip RF breast ablation may kill more tumor cells in vivo with a single application than the multiprobe RF breast ablation.

Increased hepatitis C virus (HCV)-specific CD4+CD25+ regulatory T lymphocytes and reduced HCV-specific CD4+ T cell response in HCV-infected patients with normal versus abnormal alanine aminotransferase levels.

CD4+CD25+ T regulatory cells may play a role in the different clinical presentations of chronic hepatitis C virus (HCV) infection by suppressing CD4+ T cell responses. Peripheral CD4+CD25+ T cells from chronic HCV carriers with normal and abnormal alanine aminotransferase (ALT) were analysed for specificity and effect on HCV-specific CD4+ T cell reactivity by flow cytometry for intracellular cytokine production and proliferation assay. HCV-specific CD4+CD25(+high) T cells consistently produced transforming growth factor (TGF)-beta but only limited amounts of interleukin (IL)-10 and no IL-2 and interferon (IFN)-gamma. The HCV-specific TGF-beta response by CD4+CD25(+high) T cells was significantly greater in patients with normal ALT compared to patients with elevated ALT. In addition, a significant inverse correlation was found between the HCV-specific TGF-beta response by CD4+CD25(+high) T cells and liver inflammation. In peripheral blood mononuclear cells (PBMC), both HCV antigen-induced IFN-gamma production and proliferation of CD4+ T cells were greater in patients with elevated ALT compared with patients with normal ALT. Depletion of CD4+CD25+ cells from PBMC resulted in an increase of both IFN-gamma production and proliferation of HCV-specific CD4+ T cells that was significantly greater in patients with normal ALT levels compared with patients with elevated ALT. In addition, CD4+CD25+ T cells from patients with normal ALT levels proved to be significantly more potent to suppress CD4+ T cell reactivity with respect to those from patients with elevated ALT. In conclusion, these data support the hypothesis that CD4+CD25+ cells may play a role in controlling chronic inflammatory response and hepatic damage in chronic HCV carriers.

Ribavirin increases mitogen- and antigen-induced expression of CD40L on CD4+ T cells in vivo.

Here, CD40L expression and cytokine production have been analysed in peripheral blood cells from orthotopic liver transplantation (OLT) recipients treated with ribavirin for recurrent chronic hepatitis C. The study included 18 OLT recipients treated with ribavirin, eight control OLT recipients and 10 healthy controls. FACS analysis showed that baseline expression of CD40L was not different between ribavirin-treated patients and controls. In contrast, after stimulation with both HCV core antigen and phorbol myristate acetate (PMA) plus ionomycin (IO), the expression of CD40L on CD4 lymphocytes was significantly higher in the ribavirin group compared with controls. In the ribavirin group, the increased expression of CD40L significantly correlated with reduction of HCV RNA levels with respect to pretreatment values. Finally, ribavirin treatment was not associated with modification of PMA-IO-induced cytokine production by T lymphocytes and interleukin (IL)-1beta and tumour necrosis-alpha (TNF)-alpha production by CD40L-stimulated monocytes. In conclusion, these data indicate that ribavirin -upmodulates CD40L expression on CD4 T cells, a property which may account in part for its ability to enhance the antiviral activity of interferon-alpha in the treatment of chronic HCV infection.

Quinoxalinylethylpyridylthioureas (QXPTs) as potent non-nucleoside HIV-1 reverse transcriptase (RT) inhibitors. Further SAR studies and identification of a novel orally bioavailable hydrazine-based antiviral agent.

Quinoxalinylethylpyridylthioureas (QXPTs) represent a new class of human immunodeficiency virus type 1 (HIV-1) non-nucleoside reverse transcriptase (RT) inhibitors (NNRTIs) whose prototype is 6-FQXPT (6). Docking studies based on the three-dimensional structure of RT prompted the synthesis of novel heteroarylethylpyridylthioureas which were tested as anti-HIV agents. Several compounds proved to be potent broad-spectrum enzyme inhibitors and significantly inhibited HIV-1 replication in vitro. Their potency depends on the substituents and the nature of the heterocyclic skeleton linked to the ethyl spacer, and structure-activity relationships are discussed in terms of the possible interaction with the RT binding site. Although the new QXPTs analogues show potent antiviral activity, none of the compounds tested overcome the pharmacokinetic disadvantages inherent to ethylpyridylthioureidic antiviral agents, which in general have very low oral bioavailability. Through an integrated effort involving synthesis, docking studies, and biological and pharmacokinetic evaluation, we investigated the structural dependence of the poor bioavailability and rapid clearance within the thioureidic series of antivirals. Replacing the ethylthioureidic moiety with a hydrazine linker led to a new antiviral lead, offering promising pharmacological and pharmacokinetic properties in terms of antiviral activity and oral bioavailability.

Treatment with ribavirin and interferon-alpha reduces interferon-gamma expression in patients with chronic hepatitis C.

Recent studies in vitro and in animals have suggested that ribavirin may potentiate the antihepatitis C virus (HCV) activity of interferon-alpha (IFN-alpha) by up-modulating the production of T cell-derived cytokines, such as interleukin (IL)-2 and IFN-gamma, which play a key role in the cellular immune response against HCV. To study the immune-modulatory mechanisms of ribavirin further, cytokine production by activated T cells and circulating cytokine levels were studied by FACS analysis and ELISA testing in 25 patients with chronic hepatitis C unresponsive to IFN-alpha, before and after treatment with either ribavirin plus IFN-alpha or IFN-alpha alone. After 16 weeks of treatment, both the expression of IFN-gamma by activated T cells and the blood levels of IFN-gamma, were significantly reduced with respect to pretreatment values in patients treated with ribavirin and IFN-alpha but not in those undergoing treatment with IFN-alpha alone. The expression of IFN-gamma was significantly lower in patients that gained normal ALT levels with respect to those that did not. No modification of the expression of IL-2, IL-4 and IL-10 was found before and after treatment in either group of patients. In conclusion, the results of this study do not support up-modulation of IFN-gamma and IL-2 production as the mechanism by which ribavirin potentiates IFN-alpha anti HCV activity. In addition, our findings suggest that ribavirin may exert an anti-inflammatory effect and may help reducing IFN-gamma-driven T cell activation and liver damage.

Lack of evidence for the Th2 predominance in patients with chronic hepatitis C.

A T helper (Th)1 to Th2 shift has been proposed to be a critical pathogenic determinant in chronic hepatitis C. Here, we evaluated mitogen-induced and hepatitis C virus (HCV) core antigen-induced cytokine production in 28 patients with biopsy-proven chronic hepatitis C. Flow cytometry demonstrated that after mitogenic stimulation the percentage of Th2 cells (IL-4 + or IL-13 +) and Th0 cells (IFN-gamma/IL-4 + or IL-2/IL-13 +) did not differ between patients and controls. In contrast, the percentage of Th1 cells (IFN-gamma + or IL-2 +) was significantly increased in CD4 +, CD8 +, 'naive'-CD45RA + and 'memory'-CD45RO + T-cell subsets from patients versus controls. Similar results were obtained by ELISA testing supernatants from mitogen-stimulated, unfractionated peripheral blood mononuclear cell (PBMC) cultures. Interferon-alpha treatment was associated with a reduction in the mitogen-induced Th1 cytokine response in those patients who cleared their plasma HCV-RNA. Analysis of cytokine expression by CD4 + T cells after HCV core antigen stimulation in a subgroup of 13 chronic hepatitis C patients demonstrated no cytokine response in 74% of these patients and an IFN-gamma-restricted response in 26%. Finally, no Th2 shift was found in lipopolysaccharide-stimulated monocytes. These data indicate that a Th1 to Th2 shift does not occur in chronic hepatitis C.

Effect of different activation stimuli on the cytokine response of human macrophages to CD40L.

Here we show that CD40L (ligand for CD40) failed to induce the production of tumour necrosis factor alpha (TNF-alpha), interleukin (IL-)-1 beta, IL-10 and IL-12 in macrophages matured in vitro in the absence of growth factors or in the presence of macrophage colony-stimulating factor (M-CSF). In contrast, enzyme-linked immunoabsorbent assay (ELISA) testing and cytofluorimetric (FACS) analysis demonstrated significant production of TNF-alpha and IL-1 beta, but not of IL-10 and IL-12 in macrophages maturated in the presence of CD40L and re-stimulated with CD40L. The priming effect of CD40L on TNF-alpha and IL-1 beta production was related to induction of CD40 expression. Finally, CD40L priming did not modify the cytokine response of macrophages to lipopolysaccharide. In conclusion, our results suggest that CD40/CD40L interactions are important for the activation of macrophages as effector cells that mediate inflammation and tissue damage in T cell-mediated inflammatory processes.

Granulocyte-macrophage colony-stimulating factor regulates cytokine production in cultured macrophages through CD14-dependent and -independent mechanisms.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) has multiple effects on the antigen phenotype and function of macrophages. In this study we investigated the effect of GM-CSF on cytokine production by macrophages. We found that GM-CSF may modify the tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) response to lipopolysaccharide (LPS) through two different mechanisms. Relatively early in culture, GM-CSF increases the amount of cytokines synthesized by responding cells; this effect appears to be unrelated to modulation of CD14 expression and LPS-binding capacity. After prolonged incubation, GM-CSF up-regulates both CD14 expression and LPS-binding capacity, and the frequency of cytokine-producing cells. Release of CD14 in the culture supernatant was decreased in the presence of GM-CSF, suggesting that a reduced shedding was responsible for the effect of GM-CSF on CD14 expression. Enhancement of cytokine production was also observed in GM-CSF-treated macrophages after stimulation by phorbol 12-myristate 13-acetate (PMA), thus indicating that GM-CSF affects both CD14-dependent and -independent cytokine production. Finally, GM-CSF did not modulate the LPS- and PMA-induced production of IL-10 and IL-12. We conclude that GM-CSF may play a role in manipulating the activation-induced expression of pro-inflammatory cytokines by macrophages. Enhanced production of these cytokines could play an important role in the pathogenesis of Gram-negative septic shock syndrome and in defence against infectious agents.

Human immunodeficiency virus type 1 infection modulates the interleukin (IL)-1beta and IL-6 responses of human macrophages to CD40 ligand stimulation.

Better understanding of the mechanisms of proinflammatory cytokine production during human immunodeficiency virus (HIV) type 1 infection is of pivotal importance. The effect of HIV-1 infection on recombinant CD40 ligand (CD40L)-induced interleukin (IL)-1beta and IL-6 production by human macrophages was analyzed. ELISA and cytofluorometric analysis demonstrated that CD40L stimulation of HIV-1-infected macrophages resulted in substantial production of IL-1beta and IL-6. In contrast, no cytokine response was observed in uninfected cells. No modulation of the receptor for CD40 was found to account for the enhanced response to CD40L. The CD40L effect was not due to lipopolysaccharide contamination and was completely abrogated by preincubation with a monoclonal anti-CD40L antibody. mRNA studies indicated that the priming effect of HIV-1 on the macrophage response to CD40L was regulated at the transcriptional level. Finally, the effect of HIV-1 on the cytokine response could not be abolished by the HIV-1 protease inhibitor U75875 at concentrations that completely suppressed HIV-1 replication.

Non-nucleoside HIV-1 reverse transcriptase inhibitors: synthesis and biological evaluation of novel quinoxalinylethylpyridylthioureas as potent antiviral agents.

New heterocyclic derivatives of ethylpyridylthiourea, quinoxalinylethylpyridylthiourea (QXPT) and analogues, inhibited human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) activity and prevented HIV-1 cytopathogenicity in T4 lymphocytes. Several of these novel non-nucleoside RT inhibitors, with a substituted pyrroloquinoxalinone heteroaromatic skeleton, showed inhibitory activity against wild-type RT as well as against mutant RTs containing the single amino acid substitutions L1001, K103N, V106A, Y1811 and Y188L that was much greater than other non-nucleoside inhibitors such as nevirapine. Maximum potency in enzymatic assays was achieved with a fluoropyrroloquinoxaline skeleton linked to the ethylpyridylthiourea moiety (FQXPT). In cell-based assays on different cell lines and on human monocyte-macrophages, 6-FQXPT exhibited EC50 values in the nanomolar range, with a promising selectivity index. Moreover, 6-FQXPT showed synergistic antiviral activity with zidovudine.