Belimumab restores Treg/Th17 balance in patients with refractory systemic lupus erythematosus

Belimumab, a specific inhibitor of the soluble B lymphocyte stimulator (BlyS), is the first biological drug approved by the United States Food and Drug Administration for the treatment of patients with active systemic lupus erythematosus (SLE) refractory to standard therapy. Given that an imbalance between regulatory T cells (Treg) and interleukin (IL)-17A-secreting T cells (Th17) has been reported in various autoimmune disorders, we assessed the frequency of both Treg and Th17 peripheral blood populations before and after belimumab administration in 20 patients with active SLE refractory to standard therapy. After six months of treatment, the mean SELENA-SLEDAI score as well as the mean anti-double-stranded DNA antibody titers were significantly decreased. In addition, we observed a significant increase in Treg percentages and a parallel, significant decrease in Th17 percentages, accompanied by significantly reduced serum levels of IL-21. In vitro studies showed that Treg purified from belimumab-treated patients were fully functional and displayed a suppressor function similar to that of Treg purified from healthy donors. Belimumab can restore Treg/Th17 balance in SLE patients with uncontrolled disease activity, and this results in decreased flare rate and reduced glucocorticoid dosage.

Macrophages in Skin Cancer: Quantitative and Functional Studies

The number of tumor-infiltrating macrophages was estimated in 43 patients with skin cancer, including 18 cases of squamous cell and 25 cases of basal cell carcinoma. Macrophages were identified in cell cultures by 2 assays, namely phagocytosis and resistance to detachment by trypsin. The average percentage of adherent cells for the 2 groups of skin tumors was 4.5 ± 2.6 and 10.2 ± 5.2, respectively, and the difference was statistically significant. Follow-up studies after surgical excision of the primary neoplasm showed a relatively low macrophage content in 2 of the 4 cases in which local recurrences occurred. Preliminary functional studies suggested that soluble factors may be released by neoplastic cells, accounting for the inhibitory effect of tumor cell supernatants on macrophage Chemotaxis in vitro.

HCV RNA Genomic sequences and HCV-E2 glycoprotein in sural nerve biopsies from HCV-infected patients with peripheral neuropathy

AIMS

Peripheral neuropathy (PN), the major neurological complication of chronic HCV infection, is frequently associated with mixed cryoglobulinaemia (MC) and small-vessel systemic vasculitis. While humoral and cell-mediated immune mechanisms are suspected to act together in an aberrant immune response that results in peripheral nerve damage, the role of HCV remains largely speculative. The possible demonstration of HCV in peripheral nerve tissue would obviously assume important pathogenic implications.

METHODS

We studied sural nerve biopsies from 11 HCV-positive patients with neuropathic symptoms: five with and six without MC. In situ hybridization (ISH) and immunofluorescence studies were carried out to detect genomic and antigenomic HCV RNA sequences and HCV-encoded E2-glycoprotein, respectively.

RESULTS

Epineurial vascular deposits of E2-glycoprotein were found in four (80%) MC and in two (33.3%) non-MC patients, respectively. These findings were enhanced by the perivascular deposition of positive-, though not negative-strand replicative RNA, as also found in the nerve extracts of all patients. Mild inflammatory cell infiltrates with no deposits of immunoglobulins and/or complement proteins were revealed around small vessels, without distinct vasculitis changes between MC and non-MC patients.

CONCLUSIONS

These results indicate that nerve vascular HCV RNA/E2 deposits associated to perivascular inflammatory infiltrates were similar in chronically HCV-infected patients, regardless of cryoglobulin occurrence. Given the failure to demonstrate HCV productive infection in the examined sural nerve biopsies, nerve damage is likely to result from virus-triggered immune-mediated mechanisms.

Activation-induced cytidine deaminase in B cells of hepatits C virus-related cryoglobulinaemic vasculitis

Immunoglobulin variable region heavy chain (IgVH ) somatic gene diversification is instrumental in the transformation process that characterizes hepatitis C virus (HCV)-related B cell lymphoproliferative disorders. However, the extent to which activation-induced cytidine deaminase (AID), an enzyme essential for IgV gene somatic hypermutation (SHM), is active in cryoglobulinaemic vasculitis (CV) remains unclear. AID mRNA expression in the peripheral blood of 102 chronically hepatitis C virus (HCV)-infected patients (58 with and 44 without CV) and 26 healthy subjects was investigated using real-time reverse transcription-polymerase chain reaction (RT-PCR). The features of activation-induced cytidine deaminase (AID) protein and mRNA transcripts were explored in liver tissue biopsies and portal tracts isolated using laser capture microdissection. In chronically HCV-infected patients, AID mRNA expression was almost threefold higher in those with than in those without CV and sevenfold higher than in healthy subjects (median-fold: 6.68 versus 2.54, P = 0.03 and versus 0.95, P = 0.0003). AID transcript levels were significantly higher in polyclonal than in clonally restricted B cell preparations in either CV or non-CV patients (median-fold, 15.0 versus 2.70, P = 0.009 and 3.46 versus 1.58, P = 0.02, respectively). AID gene expression was found to be related negatively to age and virological parameters. AID protein was found in portal tracts containing inflammatory cells that, in several instances, expressed AID mRNA transcripts. Our data indicate that the aberrant expression of AID may reflect continuous B cell activation and sustained survival signals in HCV-related CV patients.

Four proteins governing overangiogenic endothelial cell phenotype in patients with multiple myeloma are plausible therapeutic targets

Bone marrow (BM) angiogenesis has an important role in the initiation and progression of multiple myeloma (MM). We looked at novel mechanisms of vessel formation in patients with MM through a comparative proteomic analysis between BM endothelial cells (ECs) of patients with active MM (MMECs) and ECs of patients with monoclonal gammopathy of undetermined significance (MGECs) and of subjects with benign anemia (normal ECs). Four proteins were found overexpressed in MMECs: filamin A, vimentin, α-crystallin B and 14-3-3ζ/δ protein, not yet linked to overangiogenic phenotype. These proteins gave a typical distribution in the BM of MM patients and in MMECs versus MGECs, plausibly according to a different functional state. Their expression was enhanced by vascular endothelial growth factor, fibroblast growth factor 2, hepatocyte growth factor and MM plasma cell conditioned medium in step with enhancement of MMEC angiogenesis. Their silencing RNA knockdown affected critical MMEC angiogenesis-related functions, such as spreading, migration and tubular morphogenesis. A gradual stabilization of 14-3-3ζ/δ protein was observed, with transition from normal ECs to MGECs and MMECs that may be a critical step for the angiogenic switch in MMECs and maintenance of the cell overangiogenic phenotype. These proteins were substantially impacted by anti-MM drugs, such as bortezomib, lenalidomide and panobinostat. Results suggest that these four proteins could be new targets for the antiangiogenic management of MM patients.

Cyclosporin-A efficacy in chronic idiopathic urticaria

Common drugs in the therapy of chronic idiopathic urticaria (CIU) include antihistamines alone or combined with corticosteroids, but severe unresponsive patients require alternative treatments. This retrospective study aims to evaluate clinical response and safety of low-dose and long-term oral Cyclosporin-A (CyA) in unresponsive patients. One hundred and ten CIU patients, unresponsive to a previous treatment (antihistamines plus prednisone 0.2 mg/kg/day), received additional oral CyA 1–3 mg/kg/day for 6 months. The patients were subdivided into three groups (A, B, C) according to the different CyA doses. Parameters of clinical efficacy including pruritus, and size and number of wheals were evaluated at baseline, after three and six months. All adverse events were recorded. The mean total symptom severity score decreased by 63% in Group A, 76% in Group B, and 85% in Group C after 6 months. Total disappearance of the symptoms was recorded in 43 patients (39.1%): 7 (28%) of Group A; 12 (37.5%) of Group B and 24 (45%) of Group C. After a mean of 2 months from CyA suspension, 14 patients (11%) had recurrence of symptoms. Minor side effects were noted in 8 patients (7%). Our study indicates that low-dose, long-term CyA therapy is efficacious and safe in severe unresponsive CIU.

CD20-depleting therapy in autoimmune diseases: from basic research to the clinic

The B lymphocyte-associated antigen CD20 is becoming an important immunotherapy target for autoimmune diseases, although its biological function has not been defined. Besides rheumatoid arthritis, growing experience with B cell-depleting therapy indicates that it may be effective in Sjögren's syndrome, dermatomyositis-polymyositis, systemic lupus erythematosus and some types of vasculitides. However, controlled clinical trials are still lacking for some of these indications. Infection has not been seen as a major limitation to this therapy, but reports of progressive multifocal leukoencephalopathy in an extremely small number of patients are of concern. Here, we review the therapeutic actions of anti-CD20 antibodies, and the recent and ongoing clinical trials with CD20-depleting therapy in autoimmune diseases.

Managing myelodysplastic symptoms in elderly patients

Most patients with myelodysplastic syndromes (MDS) are elderly (median age range 65 to 70 years); as a consequence, the incidence and prevalence of these diseases are rising as the population ages. Physicians are often uncertain about how to identify patients who may benefit from specific treatment strategies. The International Prognostic Scoring System is a widely used tool to assess the risk of transformation to leukemia and to guide treatment decisions, but it fails to take into account many aspects of treating elderly patients, including comorbid illnesses, secondary causes of MDS, prior therapy for MDS, and other age-related health, functional, cognitive, and social problems that affect the outcome and managing of myelodysplastic symptoms. Patients with low-risk disease traditionally have been given only best supportive care, but evidence is increasing that treatment with novel non-conventional drugs such as lenalidomide or methyltransferase inhibitors may influence the natural history of the disease and should be used in conjunction with supportive-care measures. Supportive care of these patients could also be improved in order to enhance their quality of life and functional performance. Elderly patients commonly have multiple medical problems and use medications to deal with these. In addition, they are more likely to have more than one health care provider. These factors all increase the risk of drug interactions and the consequent treatment of toxicities. Manifestations of common toxicities or illnesses may be more subtle in the elderly, owing to age-associated functional deficits in multiple organ systems. Particularly important to the elderly MDS patient is the age-related decline in normal bone marrow function, including the diminished capacity of response to stressors such as infection or myelosuppressive treatments. Through the integration of geriatric and oncological strategies, a personalized approach toward this unique population may be applied. As with many diseases in the elderly, reliance on family members or friends to maintain the prescribed treatments, including travel to and from appointments, may place additional stressors on the patient and his/her support network. Careful evaluation and knowledge of functional status, ability to tolerate treatments, effect of disease progression, and general overall health conditions can provide the best opportunity to support these patients. Immediate assessment of daily living activities may detect deficiencies or deficits that often require early interventions.

Blockade of the Ras pathway by manumycin, a farnesyltransferase inhibitor, overcomes the resistance of myeloma plasma cells to Fas-induced apoptosis

Ras activation (by point mutation or binding of IL-6) is frequently observed in multiple myeloma (MM). As farnesylation of Ras protein by farnesyltransferase is a critical step for Ras functional activity, farnesyltransferase inhibitors (FTI) have emerged as potential anti-cancer agents. Manumycin, a natural FTI, prevents proliferation and induces apoptosis of myeloma cells refractory to Fasand drug-induced cell death. Fas pathway analysis showed that Fas-resistant apoptosis of Fas-positive myeloma cells parallels FLIP (FLICE/caspase-8-inhibitory protein) expression. Treatment of fresh purified myeloma cells, myeloma cell clone-2 and U266 cell line with manumycin induced down-regulation of FLIP expression with concomitant expression of Apo 2.7 antigen, the marker of early apoptosis. Down-regulation of FLIP mRNA levels in drug-treated cells was associated to suppression of the transcription factor NF-kappaB that plays a central role in chemoresistance, survival and proliferation of myeloma cells. Further analysis showed that manumycin-induced apoptosis involved caspases activation and was prevented by the addition of caspases specific inhibitors. Finally, pretreatment of Fas-resistant/FLIP-positive cells with manumycin sensitised them to Fas-triggered apoptosis. Overall results indicate that manumycin-induced apoptosis involves Fas pathway. FTIs may thus be proposed as a promising class of anti-cancer agents which can boost the cytotoxic effect of conventional drugs by overcoming NF-kappaB activation and Fas-resistant apoptosis.

[The advent of biosimilars: new rules to guarantee patient safety]

Biosimilars are medicinal products proposed as copies of biotech drugs whose patents have expired. Their entry into the therapeutic armamentarium entails knowledge of the rules established in Europe relevant to their use in clinical practice. In September 2007, an Italian panel of experts comprising two nephrologists, a clinical immunologist, an oncohematologist, a pharmacologist, and a hospital pharmacist examined the main features of biotech drugs and the issues faced by the regulatory authorities in the definition of a specific approval pathway for biosimilars in Europe. The panel of experts agreed that it is important to inform the medical and scientific community that biosimilars are not exact copies of their reference products; therefore the rules governing their clinical use are not the same as those established for biotech drugs in general. Patient safety should be the fundamental principle guiding therapeutic choices, and making these choices should be the prerogative of physicians.

Delayed complete remission in a patient with multiple myeloma

We report a strikingly positive, late response to bortezomib in conjunction with pegylated liposomal doxorubicin in a 79-year old woman with multiple myeloma (MM). The patient obtained a partial remission after eight courses of therapy and a complete remission about 10 months after the end of therapy. This delayed complete remission may be similar to the spontaneous regression reported for other malignancies such as melanoma or lymphoma. We postulate that the immune response and a persistent anti-angiogenic effect of bortezomib could well explain the delayed complete remission in our patient.

Overexpression of interleukin-12 and T helper 1 predominance in lupus nephritis

Imbalance of cytokine homeostasis is a prominent feature of both experimental and human systemic lupus erythematosus (SLE). Because interleukin (IL)-12 promotes interferon (IFN)-gamma production leading to polarization of peripheral cells toward a T helper (Th) 1 phenotype, we investigated its role in lupus nephritis (LN). Soluble Th1 and Th2 cytokines were measured by enzyme-linked immunosorbent assay (ELISA) in sera and urines of SLE patients and controls. Th1/Th2 peripheral lymphocyte polarization was determined by flow cytometry. Glomerular accumulation of IL-12 was evaluated by immunohistochemistry, whereas urinary IL-12 was evaluated by ELISA. Higher serum IL-12 levels in SLE were associated with LN, whereas IL-4 was unrelated to the renal damage. Peripheral cells from LN patients showed a Th1 phenotype with a high IFN-gamma expression that paralleled the severity of renal damage. IL-12 was present within glomerular mononuclear cells in classes IV and V LN, and its accumulation was correlated strongly with urinary levels. IL-12 overexpression in SLE may contribute to the development of LN. Both serum and urinary IL-12 elevation reflect its glomerular production and parallel Th1 polarization of peripheral T cells and high IFN-gamma production. In SLE patients, IL-12 measurement may thus be predictive of the development of LN.

Current and emerging therapeutic approaches in HCV-related mixed cryoglobulinemia

Recognition of hepatitis C virus (HCV) as an etiological factor in mixed cryoglobulinemia (MC) has dramatically changed our point of view in its treatment. Emphasis is placed on abatement and clearance of viral load and deletion of clonal expansions of IgM molecules with rheumatoid factor activity-synthesising B cells. The purpose of this review is to discuss the underlying scientific rationale and results of clinical studies of new treatment approaches to MC, with a focus on cell-depleting therapies and chemokine blockade. Additional antiviral agents directed to several phases of HCV life cycle acting with different or alternate mechanisms are proposed with the goal to enhance response rates more broadly suitable for MC patients with vasculitis and peripheral neuropathies. The majority of the available data on these new treatment approaches stems from open-label studies, but controlled trials are under way. Therapy directed against chemokines and/or cytokines represents an interesting and promising future target.

New therapies in multiple myeloma

The melphalan-prednisone regimen has been considered as standard therapy for patients with multiple myeloma (MM) for many years. Recently, high-dose chemotherapy with stem-cell support has extended progression-free survival and increased overall survival, and it is now considered conventional therapy in younger patients. However, most patients relapse and the salvage treatment is not very effective. New active drugs, including immunomodulatory agents, thalidomide (Thal) and lenalidomide, and the proteasome inhibitor bortezomib, have shown promising anti-myeloma activity. These novel treatments are aimed at overcoming resistance of tumour cells to conventional chemotherapy, acting both directly on myeloma cells and indirectly by blocking the interactions of myeloma cells with their local microenvironment and suppressing growth and survival signals induced by autocrine and paracrine loops in the bone marrow. Thal has been widely studied, mostly in combination regimens in patients with relapsed MM and, more recently, in front-line therapy, showing efficacy in terms of response rate and event-free survival. Bortezomib has been found to possess remarkable activity, especially in combination with other chemotherapeutic agents, in relapsed/refractory and newly diagnosed MM, as well as in patients presenting adverse prognostic factors. Lenalidomide, in combination with dexamethasone, is showing high overall response rates in relapsed and refractory MM and promising results also in first-line therapy. In this paper, the results of the most significant trials with Thal, bortezomib and lenalidomide are reported. Several ongoing clinical studies will hopefully allow the identification of the most active combinations capable of improving survival in patients with MM.

Vasculogenic mimicry by bone marrow macrophages in patients with multiple myeloma

Bone marrow macrophages of patients with active and nonactive multiple myeloma (MM), monoclonal gammopathies of undetermined significance (MGUS) and benign anemia (controls) were stimulated for 7 days with vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), and analysed for the expression of endothelial cell (EC) markers by reverse transcription (RT)-PCR, real-time RT-PCR, western blot and immunofluorescence. Their vasculogenic ability was investigated in vitro in a Matrigel assay and in vivo on bone marrow biopsies through dual immunofluorescence and confocal laser microscopy. Active MM macrophages exposed to VEGF and bFGF acquired EC markers and formed capillary-like structures mimicking paired bone marrow ECs (multiple myeloma patient-derived endothelial cells, MMECs), with major responsiveness compared to macrophages from nonactive MM, MGUS or controls. Bone marrow biopsies of active MM harbored 'mosaic' vessels, being formed by MMECs, EC-like macrophages and macrophages themselves. These figures were rare in nonactive MM and absent in MGUS or controls. Our data indicate that macrophages contribute to build neovessels in active MM through vasculogenic mimicry, and this ability proceeds parallel to progression of the plasma cell tumors. Macrophages may be a target for the MM antivascular treatment.

Erythropoietin/erythropoietin-receptor system is involved in angiogenesis in human hepatocellular carcinoma

Ribatti D, Marzullo A, Gentile A, Longo V, Nico B, Vacca A & Dammacco F (2007) Histopathology50, 591–596 Erythropoietin/erythropoietin-receptor system is involved in angiogenesis in human hepatocellular carcinoma

Hepatitis C virus infection, cryoglobulinaemia, and beyond

Hepatitis C virus (HCV) infection is the major cause of mixed cryoglobulinaemia (MC), an immune complex (IC)-mediated systemic vasculitis mainly involving the small blood vessels. The precise mechanism of cryoprotein production is currently unknown. HCV virions and non-enveloped core protein participate in the formation of cold-insoluble ICs. Cryoglobulinaemic patients represent a distinct HCV-infected population, in that significant HCV enrichment of lymphoid cells is accompanied by evidence of productive virus infection and increased frequency of B cells. Liver, the major target organ of HCV, is the site of accumulation of inflammatory infiltrates that shares many architectural features with lymphoid tissue and reflects a distorted homeostatic balance between factors that enhance cellular recruitment, proliferation and retention, and those that decrease cellularity (cell death and emigration). There is now overwhelming evidence of a direct contribution to B-cell growth and survival through production of a variety of cytokines and chemokines. Liver tissue over-expression and abnormal circulating levels of B-cell activating factor belonging to the TNF family can provide effective costimulatory mechanisms to sustain the B-cell clonal expansion, which constitutes molecular stigmata of MC. Indolent lymphoproliferation might act as the starting point of chronic, multistage lymphomagenesis. An innovative therapeutic strategy is directed to 'eradication of the virus' and deletion of B-cell clonalities.

Hepatitis C virus productive infection in mononuclear cells from patients with cryoglobulinaemia

The relationship between the occurrence of cryoglobulins and hepatitis C virus (HCV) productive infection in peripheral blood and bone marrow-derived lymphocytes was explored. HCV minus strand RNA, the viral replicative intermediate, was searched for by a polyA(+) tract strand-specific Tth-based reverse transcriptase-polymerase chain reaction (RT-PCR) in lymphoid cells of 46 patients with acute and chronic infection. The HCV minus strand was demonstrated in RNA extracted from six (13%) and five (11%) peripheral blood and bone marrow-derived lymphocytes, respectively. The HCV replicating form in lymphoid cells was associated strictly with mixed cryoglobulinaemia (MCG), in that it was found in six of 13 (46%) MCG patients, including two with B cell non-Hodgkin's lymphoma (NHL). No traces of HCV-negative strand RNA were found in four patients with acute hepatitis C, in 15 with chronic active hepatitis without extrahepatic disorders, in seven with monoclonal gammopathy of undetermined significance, and in seven with B-NHL without MCG. These results emphasize the direct role of the virus in the pathogenesis of MCG and support the contention that HCV is not specifically lymphotropic, its entry and replication in lymphoid cells being determined largely by selective interactions.

In vivo inhibition of human hepatocellular carcinoma related angiogenesis by vinblastine and rapamycin

This paper illustrates the use of the chick embryo chorioallantoic membrane (CAM) assay to determine the single and combined antiangiogenic effects of very low doses of vinblastine (VBL) and rapamycin (RAP) in human hepatocellular carcinoma (HCC). The angiogenic response induced by human HCC biopsy specimens was inhibited by each drug and sinergistically by their combination. Morever, immunohistochemical detection of microvessels with anti-CD31 mAB showed that their area was significantly lower in specimens treated with VBL and RAP in combination. Sinergy on the part of these well-known drugs when used in combination as antiangiogenics at very low doses may be of significance in the designing of new ways of treating HCC.

Bortezomib as an antitumor agent

The ubiquitin-proteasome pathway (UPP) is the major non-lysosomal proteolytic system in the cytosol and nucleus of all eukaryotic cells. Bortezomib (also known as PS-341 and Velcade) is a proteasome inhibitor, a novel class of cancer therapies. Bortezomib blocks multi-ubiquitinated protein degradation by inhibiting 26S proteasome activity, including regulating cell cycle, anti-apoptosis, and inflammation, as well as immune surveillance. In multiple myeloma (MM) cells, bortezomib directly induces cell stress response followed by activation of c-Jun NH(2) terminal kinase (JNK)/stress-activated protein kinase (SAPK), and triggers caspase-dependent apoptosis of tumor cells. Recent clinical studies demonstrated that bortezomib had remarkable anti-tumor activity in refractory and relapsed MM, providing the basis to approval by FDA. Its anti-tumor activities earlier in the course, in combination therapies, and in other malignancies is ongoing.

Interleukin-18 overexpression as a hallmark of the activity of autoimmune inflammatory myopathies

The objective of this study was to explore the role of interleukin (IL)-18 in patients with inflammatory myopathies (IM) such as dermatomyositis (DM) and polymyositis (PM) in relation to the possible predominance of a Th1 immune response in their pathogenesis. Serum concentrations of IL-18, interferon (IFN)-gamma, IL-4 and IL-6 were measured in six patients by enzyme-linked immunosorbent assay (ELISA). IL-18 expression was evaluated by in situ hybridization (ISH), whereas CD68, CD8 and CD83 were investigated by immunohistochemistry (IHC) to define the main producers of IL-18. Lastly, the expression of both IL-18 receptor (IL-18R) and monocyte chemoattractant protein (MCP)-1 was also explored by IHC. High serum levels of IL-18 and IFN-gamma, and conversely low titres of IL-4 and IL-6, were demonstrated in both diseases. In addition, IL-18 was overexpressed in muscle biopsy specimens from patients with IM. Both macrophages and dendritic cells (DC) surrounding either perivascular and perimysium areas in DM or endomysium in PM were the main producers of IL-18. Endothelial cells (EC), smooth muscle cells (SMC) and CD8(+) T cells expressed a high content of IL-18R. Vessel cells overexpressed MCP-1 in parallel with IL-18R. High concentrations of serum IL-18 as well as muscular up-regulation of IL-18 and IL-18R suggest that deregulation of the IL-18/IL-18R pathway is a pathogenetic mechanism in IM. Measurement of IL-18 may thus predict the severity of both DM and PM.

HCV-NS3 and IgG-Fc crossreactive IgM in patients with type II mixed cryoglobulinemia and B-cell clonal proliferations

We demonstrate that in three cases of MC (two with immunocytoma), the IgM-RF+ component of their cryoprecipitated represents the circulating counterpart of the B-cell receptor (BCR) of the monoclonal overexpanded B-cell population. These IgMs were isolated and used to demonstrate a crossreactivity against both hepatitis C virus (HCV) NS3 antigen and the Fc portion of IgG. Epitopes were identified in a fraction of exemplary samples by using epitope excision approach (NS(31250-1334) and IgG Fc(345-355)). The same phenomenon of crossreactivity has been shown to occur in vivo after immunization of a mouse with the NS3(1251-1270) peptide. To verify if the same reaction was also present in MC samples characterized by an oligo/polyclonal B-cell proliferation, IgM crossreactivity was tested in 14 additional samples. Five out of the 14 were reactive against HCV NS3 and 11 out of 14 were reactive against IgG-Fc peptide. The data support the role of HCV NS3 antigen in a subset of patients with MC, whereas the high frequency of the IgG-Fc epitope suggests that these B cells originate from precursors strongly selected for auto-IgG specificity. We suggest that engagement of specific BCRs by NS3 (or NS3-immunocomplex) antigen could explain the prevalence of IgM cryoglobulins in these patients.

Virological analysis and phenotypic characterization of peripheral blood lymphocytes of hepatitis C virus-infected patients with and without mixed cryoglobulinaemia

In clinical and pathological terms hepatitis C virus (HCV)-infected patients can be subdivided into two main groups with and without mixed cryoglobulinaemia (MC). Involvement of blood mononuclear cells by HCV has potentially important implications. To this end, HCV-RNA levels in peripheral blood lymphocytes (PBL) preparations of 20 chronically HCV-infected patients with MC were measured and compared with those found in a group of 20 patients without MC matched for age, serum HCV-RNA, infectious genotype, source and presumable duration of infection. Phenotypic abnormalities of PBL subsets in each group of patients were determined by cell surface marker expression and compared. Results showed a significant enrichment of HCV-RNA in PBL of MC patients compared with a non-MC group (P = 0.01). Different distribution of HCV-RNA was accompanied by evidence of an increased frequency of circulating B cells. These data indicate that MC patients are characterized distinctly by a higher quota of cell-associated viral load.

Type II mixed cryoglobulinaemia as an oligo rather than a mono B-cell disorder: evidence from GeneScan and MALDI-TOF analyses

OBJECTIVE

To identify and characterize rheumatoid factor (RF)-producing B-cells and cryoprecipitate immunoglobulin (Ig) M in hepatitis C virus (HCV)-positive patients.

METHODS

We purified and characterized, by peptide mass fingerprinting integrated with an NCBI IgBlast data bank search, the IgM component of cryoprecipitate and analysed the VDJ pattern of bone marrow B-cells by gene scan analysis of 17 HCV-positive patients with type II mixed-cryoglobulinaemia.

RESULTS

IgM purified from all of the patients presented an RF specificity. In three of these patients a high and predominant B-cell clone (>or=30%) was found in the bone marrow. B-cell-receptor sequences were determined and immunophenotyping of these clones was performed. Peptide masses originating after tryptic digestion of the B-cell-receptor combinatory regions and those originating by tryptic digestion of the cryoprecipitated IgM from the same patient were comparable. In the remaining patients an oligoclonal/polyclonality was found. However, in some of these patients we were able to find peptides that matched with the B-cell-receptor sequences of overexpanded B cells, indicating that, even in the absence of a clear monoclonal expansion, a fraction of total cryoprecipated IgM may derive from overexpanded B-cell clones found in patients' bone marrow.

CONCLUSIONS

In the majority of mixed cryoglobulinaemia-HCV-positive patients, both in the serum and in B cells from the bone marrow, an oligoclonal pattern is the main molecular picture. When a monoclonal B-cell clone is found, its B-cell-receptor shows an antigen-binding fragment identical to that of cryoprecipitable RF-IgM. Phenotypically, B cells are CD20-positive but CD5-negative, suggesting that the B-1 B-cell subset is not likely to produce high-affinity IgM-RF molecules.

Biological therapy with monoclonal antibodies: a novel treatment approach to autoimmune disease

Most autoimmune diseases (ADs) are still associated with high morbidity and mortality despite the use of a wide range of drugs that can delay their progression, control their symptoms, but never bring about a complete cure. This failure has aroused interest in new forms of monoclonal antibody-based experimental immunotherapy (IT), aiming at targeting cellular antigens or cytokines involved in the pathogenesis of ADs. The first part of this review offers a general overview of the molecular mechanisms that mediate the immune response and the molecule regarded as potential IT targets. A critical evaluation will then be made of some forms of IT, with particular emphasis on TNF-alpha and CD20-blocking reagents. Lastly an account will be given of active IT whereby an endogenous response against antigens regarded as the target of passive IT can be induced by anti-idiotype or peptides.

Hepatitis C virus RNA and core protein in kidney glomerular and tubular structures isolated with laser capture microdissection

The role of hepatitis C virus (HCV) in the production of renal injury has been extensively investigated, though with conflicting results. Laser capture microdissection (LCM) was performed to isolate and collect glomeruli and tubules from 20 consecutive chronically HCV-infected patients, namely 6 with membranoproliferative glomerulonephritis, 4 with membranous glomerulonephritis, 7 with focal segmental glomerulosclerosis and 3 with IgA-nephropathy. RNA for amplification of specific viral sequences was provided by terminal continuation methodology and compared with the expression profile of HCV core protein. For each case two glomeruli and two tubular structures were microdissected and processed. HCV RNA sequences were demonstrated in 26 (65%) of 40 glomeruli, but in only 4 (10%) of the tubules (P < 0.05). HCV core protein was concomitant with viral sequences in the glomeruli and present in 31 of the 40 tubules. HCV RNA and/or HCV core protein was found in all four disease types. The immunohistochemical picture of HCV core protein was compared with the LCM-based immunoassays of the adjacent tissue sections. Immune deposits were detected in 7 (44%) of 16 biopsy samples shown to be positive by extraction methods. The present study indicates that LCM is a reliable method for measuring both HCV RNA genomic sequences and HCV core protein in kidney functional structures from chronically HCV-infected patients with different glomerulopathies and provides a useful baseline estimate to define the role of HCV in the production of renal injury. The different distribution of HCV RNA and HCV-related proteins may reflect a peculiar 'affinity' of kidney microenvironments for HCV and point to distinct pathways of HCV-related damage in glomeruli and tubules.

Primary intimal sarcoma of the thoracic aorta

Primary aortic tumors are well known for both their rarity and variability in clinical presentation and usually are diagnosized post-operatively or by post-mortem examination. Intimal sarcoma is a recurrent histological variant and the involvement of the thoracic aorta is an unusual presentation. Angiography and computed tomography are accurate methods to evaluate aortic tumors though transesophageal echocardiography is actually used for the differential diagnosis. Here, we describe an unusual intimal sarcoma of the thoracic aorta whose clinical feature strongly mimicked a diffuse thrombotic disease.

Crosstalk between angiogenesis and lymphangiogenesis in tumor progression

Extensive studies have identified reliable markers of lymphatic endothelial cells, and mechanisms and molecules that regulate development and growth of the lymphatic vessels. Vascular endothelial growth factors (VEGF)-C and VEGF-D, and their cognate receptor tyrosine kinase, VEGF receptor-3 (VEGFR-3), are critical regulators of lymphangiogenesis. By binding to its endothelial cell surface receptors VEGFR-1 and VEGFR-2, VEGF-A mediates vascular leakage, endothelial proliferation and migration. Angiopoietin-2 (Ang-2) is expressed at sites of blood vessel remodeling and invasion, and factors that induce angiogenesis in vivo, such as VEGF-A, upregulate Ang-2 in endothelial cells. In this review, we summarize the literature concerning the crosstalk between angiogenesis and lymphangiogenesis in tumor progression, that is, involvement of VEGF-C, VEGF-D and VEGFR-3 in angiogenesis, and the role played by VEGF-A and Ang-2 in lymphangiogenesis, respectively.

Detection and quantitation of HCV core protein in single hepatocytes by means of laser capture microdissection and enzyme-linked immunosorbent assay

Immunohistochemistry provides valuable information concerning the localization and distribution of hepatitis C virus (HCV)-related proteins in histological sections of liver tissue, but does not readily permit their quantitation in individual cells and the staining intensity of cell immunodeposits cannot be calibrated with the current number of antigen molecules. We specifically detected and quantitated HCV core protein in single hepatocytes by coupling laser capture microdissection (LCM) with a sensitive enzyme-linked immunosorbent assay (ELISA). Quantitation of HCV core protein per cell was carried out on liver tissue cells obtained by LCM from fixed and stained frozen sections of 10 HCV-positive patients with chronic active hepatitis (CAH). Macromolecules from captured cells were solubilized in an extraction buffer and directly assayed for core protein using a sandwich ELISA. Calibration was achieved by developing a standard curve based on known concentrations of HCV core protein. Precision, linearity and sensitivity were verified for known numbers of microdissected tissue cells. In this study, the concentration of HCV core protein in single hepatocytes ranged from 7 to 56 pg/cell. Specificity was verified on 10 replicates of 10 HCV-negative liver tissues. Immunohistochemical staining of HCV core protein was compared with the results of the soluble immunoassay for the adjacent liver tissue sections. Independent scoring of HCV immunostaining failed to parallel the LCM quantitative immunoassay. LCM-based immunoassay significantly expands our ability to investigate function-related antigens in apparently pure cell populations in HCV infection.

Vascular endothelial growth factor and its receptors in multiple myeloma

Multiple myeloma (MM) progresses from an avascular to a vascular phase (active MM) accompanied by a significant increase in microvessel density in the bone marrow. This article summarizes the literature concerning the specific role played by vascular endothelial growth factor (VEGF) in this process. Recent applications of antiangiogenic agents that interfere with VEGF signaling and block MM progression are also described.

New non-angiogenesis dependent pathways for tumour growth

The current wisdom is that tumours are endowed with an angiogenic capability and that their growth, invasion and metastasis are angiogenesis-dependent. This article summarises the literature concerning recent histomorphological studies that indicate that some tumours may be vascularised without significant angiogenesis, probably by using existing vessels, a process later described as vascular co-option, or even by forming vascular channels on their own through a non-endothelial cell process called "vascular mimicry". Moreover, the possibility that bone marrow-derived stem cells may also be a source of endothelial precursor cells recruited for tumour-induced neovascularisation, is reviewed. In fact, it has been assumed that the additional endothelial cells required to construct new tumour vessels come from the division and proliferation of local endothelial cells and that endothelial cells incorporated into sites of neovascularisation, including tumour-induced new blood vessels, may be derived from these precursor cells. Finally, lymphoangiogenesis as a mechanism of de novo formation of lymphatics, favouring the metastatic dissemination of tumour cells, is summarised. Potential therapeutic applications are also discussed.

Non-enveloped HCV core protein as constitutive antigen of cold-precipitable immune complexes in type II mixed cryoglobulinaemia

Hepatitis C virus (HCV) infection has been detected in a large proportion of patients with mixed cryoglobulinaemia (MC). Circulating 'free' non-enveloped HCV core protein has been demonstrated in HCV-infected patients, and this suggests its possible involvement in the formation of cryoprecipitable immune complexes (ICs). Thirty-two anti-HCV, HCV RNA-positive patients with type II MC were evaluated. Non-enveloped HCV core protein, HCV RNA sequences, total IgM, rheumatoid factor (RF) activity, IgG and IgG subclasses, C3 and C4 fractions, C1q protein and C1q binding activity were assessed in both cryoprecipitates and supernatants. Non-enveloped HCV core protein was demonstrated in 30 of 32 (93.7%) type II MC patients. After separation of cold-precipitable material, the protein was removed completely from supernatant in 12 patients (40%), whereas it was enriched in the cryoprecipitates of the remaining 18. In addition, HCV RNA and IgM molecules with RF activity were concentrated selectively in the cryoprecipitates. Differential precipitation was found for both total IgG and IgG subclasses, as they were less represented in the cryoglobulins and no selective enrichment was noted. Immunological characterization of HCV core protein-containing cryoprecipitating ICs after chromatographic fractionation showed that the IgM monoclonal component had RF activity, whereas anti-HCV core reactivity was confined to the IgG fraction. C1q enrichment in addition to high avidity of ICs for C1q binding in the cryoprecipitates suggest that complement activation may occur through the C1q protein pathway. The present data demonstrate that non-enveloped HCV core protein is a constitutive component of cryoprecipitable ICs in type II MC patients.

Enhancement of T cell apoptosis correlates with increased serum levels of soluble Fas (CD95/Apo-1) in active lupus

Peripheral T cell apoptosis is upregulated in active SLE, in parallel with high expression of both membrane-bound and soluble (s) Fas. Previous studies postulated that sFas down-regulates apoptosis in vitro through its blockade of the Fas-L of cytotoxic cells. We have investigated the extent of apoptosis and sFas levels in 14 patients with active (group A) and 11 with inactive SLE (group B). Fas was predominantly expressed by CD3+ cells from group A, whose increased serological levels of sFas were linearly correlated with the TUNEL positive cell population, whereas low titers paralleled a mild level of apoptosis in group B. This association was also investigated by measuring the effect of sFas on both cell proliferation and caspase activation. We found that incubation with sFas greatly suppressed proliferation of CD3+ cells, especially in group B, and in control cells from healthy donors whose content of CPP32 active products was significantly increased. We postulate that sFas promotes a pro-apoptogen effect, which would explain the high susceptibility to apoptosis in active lupus, and that the apoptosis program itself includes release of sFas to spread the death signal.

Neovascularisation, expression of fibroblast growth factor-2, and mast cells with tryptase activity increase simultaneously with pathological progression in human malignant melanoma

Tissues from 92 proliferative lesions of the melanocytic lineage defining distinct steps in tumour progression were investigated immunohistochemically for changes in angiogenesis, expression of fibroblast growth factor-2 (FGF-2) and density of total mast cells (MCs) and MCs expressing tryptase, an angiogenic-inducing molecule. Although the microvessel number was low in common nevi, it increased significantly in nevi with architectural disorder with varying degrees of melanocytic atypia (termed 'nevi with ADMA'), and these changes persisted during tumour development. Progression of primary melanomas was accompanied by a high microvessel number, and the progression to metastases by another significant increase in the microvessel counts. Expression of FGF-2, evaluated as percentages of positive lesions and positive cells per lesion was upregulated in the course of progression. Changes in expression were associated with nevi with ADMA, tumour changeover, penetration of the tumour into the dermis and metastases. A high correlation was demonstrated in all groups of tissues between the microvessel counts, percentages of FGF-2-positive tumour cells, and both total metachromatic and tryptase-reactive MCs. These results suggest that angiogenesis in human melanoma increases with tumour progression and that FGF-2 secreted by tumour cells and tryptase secreted by host MCs cooperate in its induction.

Beta-2 microglobulin-free HLA class I heavy chain (FHC) A3 and/or A30 soluble products contribute only minimally to serum FHC expression

No monoclonal antibodies (mAbs) are presently available to measure the total amount of beta2-microglobulin-free HLA class I heavy chain (FHC) in sera. The available ELISA-based double determinant immunoassay (DDIA), established to measure FHC, uses two mAbs (TP25.99 and HC-10) that recognize a monomorphic determinant expressed on all HLA-B/C FHC products and a determinant expressed only on some HLA-A FHC products. This restricted reactivity implies that, in addition to HLA-B/C, HLA-A FHC products are also detected in individuals bearing HLA A3 and/or A30 allotypes. The aim of this study was to establish whether such restriction results in the detection of low FHC levels in individuals lacking HLA A3 and/or A30 allospecificities. The FHC mean concentration (+/- SD) in 294 healthy blood/bone marrow donors (HBDs) was 0.24 (+/- 0.2) mg/l. The grouping of HBDs according to their HLA-A FHC product reactivity with one, both or no mAbs did not result in any statistically significant differences (Mann-Whitney test: P > 0.05) between their median FHC concentrations. Since the absence of differences in their FHC levels was not attributable to a difference in the percentage distribution of HLA allotypes associated with high or low HLA-B/C FHC expression, our results indicate that FHC HLA A3 and/or A30 products detected in DDIA by these two mAbs only minimally contribute to FHC serum expression and that the assay is not limited by the failure to detect HLA-A FHC products in A3- and/or A30- individuals.

Correlation of bone marrow angiogenesis and mast cells with tryptase activity in myelodysplastic syndromes

Bone marrow samples from 30 patients with myelodysplastic syndromes (MDS) grouped according to the International Prognostic Scoring System for MDS were investigated for counts of microvessels, total metachromatic mast cells (MC) and MC expressing tryptase, an angiogenesis-inducing molecule. Counts were higher in patients with a poor prognosis. The observation of a high correlation between microvessel counts and both total metachromatic and tryptase-reactive MC in all samples suggests that angiogenesis in MDS increases with their progression and that MC may intervene in the angiogenic response in MDS through tryptase contained in their secretory granules.

Multiple myeloma and mycosis fungoides in the same patient: clinical, immunologic, and molecular studies

The coexistence of multiple myeloma (MM) and mycosis fungoides (MF), and hence of both B- and T-cell neoplastic clones, is a rare event. We describe a case of plaque-stage MF associated with IgG lambda MM. The clinical onset of MF preceded that of MM, supporting the hypothesis that MF predisposed to the development of the B-cell proliferative disorder. The skin tumor cells were found to originate from CD4(+) T-lymphocytes, characterized by a V beta 8 receptor and no proviral human T-lymphotropic virus (HTLV)-I monoclonal integration. They also displayed a polarized Th1-type cytokine profile containing mRNAs for interleukin (IL)-2, interferon (IFN)-gamma, and tumor necrosis factor (TNF)-beta, but not for IL-4, IL-5, or IL-10. The CD8(+)/CD57(+) suppressor-cytotoxic subpopulation was significantly increased in the peripheral blood and was associated with MM progression. Expression of p16INK4A, a gene from the INK family that inhibits cyclin-dependent kinases and regulates the cell cycle, was lacking in MF cells and bone marrow (BM) plasma cells. The p16INK4A gene was silenced by hypermethylation, suggesting that it plays a role in the early phase of the pathogenesis of both diseases. Thus, a lymphoid precursor cell presumably contains aberrations that induce the development of both clonal diseases in a multistep process.

Serum elevations of soluble Fas (CD95/apo-I) concur in deregulating T cell apoptosis during active lupus disease

Apoptosis is deregulated in active systemic lupus erythematosus and Fas is overexpressed by T cells, although the role of its soluble form (sFas) is unclear. We have explored both the biological significance and structure of sFas in relation to the disease activity. Serum levels of both sFas and sFas-L were correlated with T cell apoptosis in 26 systemic lupus eythematosus patients along with measurement of poly (ADP) ribose polymerase and CK18. In addition, both proliferative rate and change of ploidy were measured in CD3+ cells after treatment with sFas. Both sFas and sFas-L correlated with apoptosis in patients with active systemic lupus eythematosus. Incubation with sFas greatly suppressed proliferation of CD3+ cells from inactive patients and healthy donors, whereas immunoprecipitation revealed both the 48-kDa full-length Fas and the 26-kDa splicing variant in sera from active patients. We postulate that sFas is released to exert a pro-apoptogen effect. It seems possible that the apoptosis program itself includes the shedding/secretion of different forms of Fas to spread a death signal.

Bone marrow angiogenesis and plasma cell angiogenic and invasive potential in patients with active multiple myeloma

Factor VIII-related antigen-positive microvessel areas were measured by both immunohistochemistry and computerized image analysis in patients with active multiple myeloma (MM), nonactive MM and monoclonal gammopathies of undetermined significance (MGUS). A 5- to 6-fold larger area was found in patients with active MM compared to the other two groups. The conditioned medium (CM) of their bone marrow plasma cells stimulated endothelial cell proliferation and chemotaxis, monocyte chemotaxis and angiogenesis in vivo [chick embryo chorioallantoic membrane (CAM) system] more strongly and frequently than the CM of patients with nonactive MM and MGUS. An immunoassay of plasma cell lysates gave significantly higher levels of fibroblast growth factor-2 (FGF-2) in patients with active MM than in the other two groups, and a neutralizing anti-FGF-2 antibody inhibited by 54-68% the biological activity exerted by the CM in vitro and in the CAM. In situ hybridization of bone marrow plasma cells and gelatin zymography of CM showed that patients with active MM express higher levels of matrix metalloproteinase-2 (MMP-2) mRNA and protein than those with nonactive MM and MGUS, whereas MMP-9 expression and secretion overlapped in all groups. Overall data suggest that patients with active MM represent the vascular phase of plasma cell tumors that is triggered by bone marrow plasma cells, at least partly, through FGF-2 and MMP-2. Both angiogenesis and MMP-2 secretion can account for intramedullary and extramedullary spreading of plasma cells during the active MM.

Role of hematopoietic growth factors in angiogenesis

In early ontogeny, hematopoiesis is closely associated with angiogenesis. This article reviews recent studies of the effect of hematopoietic growth factors on several endothelial cell functions together with recent findings about angiogenesis and antiangiogenic therapies in hematopoietic malignancies such as leukemia, lymphoma and myeloma.

Italian cross-sectional growth charts for height, weight and BMI (6-20 y)

OBJECTIVE

To trace growth charts for height, weight and body mass index (BMI) that apply to the whole Italian population. Different charts were drawn for central-north and south Italy since children in central-north regions are known to be taller and leaner.

DESIGN

Cross-sectional study.

SETTING

A sample of schoolchildren covering 16 of the 20 Italian regions, with data collected between 1994 and 2000.

SUBJECTS

A total of 27 421 girls and 27 374 boys, aged 6-20 y.

METHODS

Height and weight were measured using portable Harpenden stadiometers and properly calibrated scales, respectively. SIEDP references are presented both as centiles and as LMS curves for the calculation of standard deviation scores. According to International Obesity Task Force, SIEDP charts for BMI include the limits for overweight and obesity, ie the centiles having, at 18 y of age, the value of 25 and 30 kg/m(2), respectively.

RESULTS

The comparison between SIEDP and Tanner et al's charts for height, still in use among most Italian paediatricians, shows that before puberty Italian children are 2-4 cm taller than their English peers. Because of these differences, Tanner's charts fail to detect, when applied to Italian children, 50-90% of short children aged 6-11 y, ie with stature below the 3rd centile of their reference population. Rolland-Cachera et al's centiles for BMI are lower than those of SIEDP standards, mainly during adolescence (up to 6.6 kg/m(2) for the 97th centile), and apply poorly to Italian children. The prevalence of overweight is 27 (boys) and 19% (girls) in south Italy vs 17 (boys) and 10% (girls) in central-north Italy.

CONCLUSIONS

These references intend to supply Italian paediatricians with a tool that avoids the use of outdated or inadequate charts, and thus should be suitable for monitoring their patients' growth.

SPONSORSHIP

Italian Society for Pediatric Endocrinology and Diabetes (SIEDP).

Mast cells and their secretory granules are angiogenic in the chick embryo chorioallantoic membrane

BACKGROUND

Many data suggest that the density of mast cells is highly correlated with the extent of both normal and pathological angiogenesis.

OBJECTIVE

In this study we have compared in an in vivo assay, the chick embryo chorioallantoic membrane, the angiogenic potential of mast cell suspensions isolated from rats, degranulated mast cells and their secretory granules.

METHODS

Gelatin sponges adsorbed with cell suspensions of rat mast cells, degranulated mast cells and their secretory granules were implanted on the top of the chorioallantoic membrane at day 8 of incubation. At day 12 the angiogenic response was evaluated macroscopically, microscopically and by a morphometric method of 'point counting'.

RESULTS

Isolated mast cells and their secretory granules, but not degranulated mast cells, induced an angiogenic response in the chorioallantoic membrane. The addition of antifibroblast growth factor-2 or antivascular endothelial growth factor antibodies reduced the angiogenic response of both mast cells and their secretory granules by 50% and 30%, respectively.

CONCLUSION

These data support the evidence that the angiogenic properties of mast cells depend on the angiogenic molecules contained in their secretory granules and indicate that fibroblast growth factor-2 and vascular endothelial growth factor are the angiogenic cytokines primarily and perhaps synergistically responsible for this vasoproliferative activity.