Modulation of macrophage inflammatory function through selective inhibition of the epigenetic reader protein SP140.

Background: SP140 is a bromodomain-containing protein expressed predominantly in immune cells. Genetic polymorphisms and epigenetic modifications in the SP140 locus have been linked to Crohn's disease (CD), suggesting a role in inflammation.

Results: We report the development of the first small molecule SP140 inhibitor (GSK761) and utilize this to elucidate SP140 function in macrophages.

Increasing the discrimination power of rapid evaporative ionisation mass spectrometry (REIMS) in analytical control tissue quality screening and cell line sample identification.

Rationale: Rapid Evaporative Ionisation Mass Spectrometry (REIMS) has been evaluated as a tool to improve analytical efficiency and add capability in areas within Pharmaceutical Research and Development (Pharma R&D). This article reports the comparison of single MS, and tandem MS/MS REIMS (REIMS and REIMS/MS) methodologies to investigate which mode produces maximum discrimination power for screening applications.

Methods: Control tissue samples and cell line suspension samples were analysed using optimised REIMS and REIMS/MS to evaluate which technique produced optimal discrimination power for control tissue and cell line identification.

Immunomodulatory activity of a methionine aminopeptidase-2 inhibitor on B cell differentiation.

Methionine aminopeptidase-2 (MetAP-2) inhibitors have potent anti-angiogenesis activity and are being developed for the treatment of solid tumours. The recently observed specific expression of MetAP-2 in germinal centre B cells suggests that it has a role in regulating B cell function. We have demonstrated a potent MetAP-2-dependent inhibitory effect on the antibody secretion from B cell receptor and CD40 co-stimulated primary human B cells in the presence of interleukin-21.

Amelioration of arthritis in two murine models using antibodies to oncostatin M.

Objective: Oncostatin M (OSM) is a member of the interleukin-6 cytokine family, with well-documented effects on cell growth and differentiation. OSM also has proinflammatory and cartilage degradative properties. The aim of this study was to investigate the significance of OSM in arthritis pathology using a neutralizing antibody in arthritis models.

Synergistic effects of glycoprotein 130 binding cytokines in combination with interleukin-1 on cartilage collagen breakdown.

Objective: To determine whether other glycoprotein 130 (gp130) binding cytokines can mimic the effects of oncostatin M (OSM) in acting synergistically with interleukin-1alpha (IL-1alpha) to induce cartilage collagen breakdown and collagenase expression, and to determine which receptors mediate these effects.

Methods: The release of collagen and proteoglycan was assessed in bovine and human cartilage explant cultures. Messenger RNA (mRNA) and protein production from immortalized human chondrocytes (T/C28a4) was analyzed by Northern blotting and specific enzyme-linked immunosorbent assays.

Discovery of novel ansamycins possessing potent inhibitory activity in a cell-based oncostatin M signalling assay.

We describe the isolation and characterisation of novel non-benzoquinone ansamycin metabolites related to geldanamycin from a culture of Streptomyces sp. S6699. The compounds possess potent inhibitory activity in a cell-based assay measuring inhibition of oncostatin M signalling in a reporter cell line utilising a secreted placental alkaline phosphatase (sPAP) readout.

The generation and characterization of antagonist RNA aptamers to human oncostatin M.

Oncostatin M (OSM) is a multifunctional member of the interleukin-6 cytokine family. OSM has been implicated as a powerful proinflammatory mediator and may represent a potentially important, novel therapeutic opportunity for treatment of established rheumatoid arthritis. To further investigate the role of OSM in inflammatory disorders, we have isolated a series of RNA aptamers that bind specifically to human OSM.

The role of oncostatin M in animal and human connective tissue collagen turnover and its localization within the rheumatoid joint.

Objective: To study the interaction of interleukin-1alpha (IL-1alpha) and oncostatin M (OSM) in promoting cartilage collagen destruction.

Methods: Bovine, porcine, and human cartilage and human chondrocytes were studied in culture. The levels of collagenase (matrix metalloproteinase 1 [MMP-1]) and tissue inhibitor of metalloproteinases 1 (TIMP-1) were measured by bioassay and enzyme-linked immunosorbent assay (ELISA).

A study of factor XIIIa and MAC 387 immunolabeling in normal and pathological skin.

Immunolabeling with two new antibodies, Factor XIIIa and MAC 387, has been studied in routinely processed biopsy specimens of normal skin, subcutaneous tissues, lymph nodes, and a variety of pathological conditions. These presumptive cell markers of the monocyte-macrophage lineage appear to label totally different and possibly mutually exclusive subsets of cells. In normal skin, Factor XIIIa labeled fixed dermal connective tissue cells, emphasizing their dendritic morphological appearance.

Pro-inflammatory mediators induce sustained release of prostaglandin E2 from human dermal microvascular endothelial cells.

The vasodilator prostaglandin E2 has been proposed as a mediator of erythema in a variety of cutaneous inflammatory reactions and prostacyclin levels have been found to be elevated in ultraviolet induced erythema. Human recombinant interleukin 1 alpha and lipopolysaccharide induced a concentration- and time-dependent release of prostaglandin E2, but not prostacyclin, from cultured neonatal and adult human dermal microvascular endothelial cells. Prostaglandin E2 was measurable at 2 h after stimulation with 1 U/ml interleukin 1 alpha, levels increased rapidly up to 6 h and more slowly up to 24 h.

An immunohistochemical study of fibrous papule of the nose: 25 cases.

Twenty-five cases of fibrous papule of the nose were studied by light microscopy and by immunohistochemistry using a panel of 4 cell markers. These included polyclonal antibodies against S100 protein and Factor XIII-a (FXIII-a), and 2 monoclonal antibodies, MAC 387 which labels monocyte derived macrophage cells and Ulex Europaeus Agglutinin-1 (UEA-1) a pan endothelial cell marker. An increase in the number of S100 protein positive cells, particularly in the upper dermis, was observed in 3 lesions.

Large cell lymphocytoma--a clinicopathological study.

Fourteen patients with large cell lymphocytoma were studied. They presented with solitary or small numbers of grouped nodules on the trunk or head and neck region, which histologically consisted of diffuse and nodular dermal aggregates of lymphoid cells. A proportion of these cells were large with clear cytoplasm and a varying degree of nuclear atypia.

The histogenesis of mammary and extramammary Paget's disease.

The histogenesis of mammary and extramammary Paget's disease has been studied by immunohistochemical staining of paraffin-embedded tissue using a panel of epithelial cell markers, which react with secretory or ductal epithelium, but not stratified epithelium. These markers included a monoclonal antibody E29 to epithelial membrane antigen EMA, the cytokeratin marker CAM 5.2 and three new monoclonal antibodies raised to human milk fat globule membrane (LICR-LON-TW19 and H.

Histiocytoma cutis: a tumour of dermal dendrocytes (dermal dendrocytoma).

The histogenesis of histiocytoma (dermatofibroma) was investigated using new antibodies that demonstrate factor XIIIa (FXIIIa) positive cells and the monocyte macrophage cell series (MAC 387), in formalin fixed tissue. The distribution of S100 protein, vimentin and Ulex europaeus agglutinin I (UEA-I) were also studied. The antibody against FXIIIa labelled the normal dermal population of fixed connective tissue cells (dermal dendrocytes) emphasizing their dendritic processes; cells that are widely distributed, but are most numerous in the papillary dermis.

The histogenesis of angiosarcoma of the face and scalp: an immunohistochemical and ultrastructural study.

Thirteen cases of angiosarcoma of the face and scalp have been examined using immunohistochemistry and electron microscopy. Endothelial cell markers have been employed in an immunoperoxidase technique on tissue that has either been routinely processed, periodate-lysine paraformaldehyde fixed (PLP) and cold processed, or fixed in methacarn. A consistent pattern of endothelial cell labeling was only achieved in the PLP fixed tissue.

The detection of endothelial cell antigens in cutaneous tissue using methacarn and periodate lysine paraformaldehyde fixation.

The use of monoclonal antibodies with endothelial cell specificity has prompted a search for methods of fixation which combine the morphology of paraffin-embedded tissue, with preservation of labile membrane antigens. Immunohistochemical staining using a variety of endothelial cell markers was compared in tissue fixed in formalin, methacarn, periodate lysine paraformaldehyde (PLP) and in frozen tissue. Whilst lectin-binding with Ulex europaeus agglutinin I (UEA) and localisation of Factor VIII-related antigen (FVIII RA) and laminin was well-visualised in methacarn-fixed and PLP-fixed tissue, fixation in PLP was necessary for the two monoclonal antibodies, PAL-E and EN4.

Histogenesis of Kaposi's sarcoma in patients with and without acquired immune deficiency syndrome (AIDS).

Immunohistochemical studies were performed in thirty skin biopsies from patients with Kaposi's sarcoma, who did and did not have the acquired immune deficiency syndrome (AIDS). Tumour histogenesis was rigorously tested using a battery of endothelial cell markers, which included two new monoclonal antibodies, EN4 and PAL E. These are both specific for endothelial cells and can be visualised in appropriately fixed paraffin embedded tissue.

Malignant angiosarcoma of the scalp: a case report with immunohistochemical studies.

A case of angiosarcoma of the scalp is reported. The histogenesis of this tumour is discussed in terms of the ultrastructural and immunohistochemical findings. This type of angiosarcoma is uncommon and carries a poor prognosis: the therapeutic alternatives are discussed.