cytoplasmic domain of tissue factor promotes liver fibrosis in mice

To evaluate the role of tissue factor (TF) and protease activated receptor (PAR)-2 in liver fibrosis. METHODSUsing CCl4 administration for eight weeks, we induced hepatic fibrosis in wild-type C57BL/6 mice and in mice with deletion of the cytoplasmic signalling domain of TF (TF§CT/§CT), deletion of PAR-2 (PAR-2-/-) and combined deletion of TF signalling domain and PAR-2 (TF§CT/§CT/PAR-2-/-). Hepatic fibrosis area was assessed by quantitative imaging of picrosirius red staining. Hepatic collagen content was assessed by hydroxyproline levels. Hepatic stellate cells (αSMA positive) and hepatic macrophages (CD68 positive) were identified by immunohistochemistry. Hepatic gene expression was determined by PCR and liver TGFβ1 content by ELISA. RESULTSCCl4 treated mice with deletion of the PAR-2 gene (PAR-2-/-) and the cytoplasmic domain of TF (TF§CT/§CT) developed significantly less hepatic fibrosis, characterised by reduced liver fibrosis area and hydroxyproline content, compared to control wildtype mice treated with CCl4. The observed reduction in histological fibrosis was accompanied by a significant decrease in the hepatic content of TGFβ, the prototypic fibrogenic cytokine, as well as fewer activated hepatic stellate cells and hepatic macrophages. Deletion of the TF cytoplasmic signalling domain reduced hepatic fibrosis to levels similar to those observed in mice lacking PAR-2 signalling but combined deletion provided no added protection against fibrosis indicating a lack of mutual modulating effects that have been observed in other contexts such as angiogenic responses. CONCLUSIONTissue factor cytoplasmic domain is involved in TF-PAR-2 signalling initiating hepatic fibrosis and is a potential therapeutic target, as its deletion would not impact coagulation.

Primary cutaneous CD30-positive anaplastic large cell lymphoma analysis

OBJECTIVE: To examine 10 cases with primary cutaneous CD30-positive anaplastic large cell lymphoma (ALCL), analyze their clinical manifestations and pathological and immunohistochemical features, and improve early diagnosis of this disease. METHODS: We studied the morphological characteristics of primary cutaneous CD30-positive ALCL using histopathological methods. Leukocyte common antigen (LCA), CD20, CD30, CD45RO, CD68, epithelial membrane antigen (EMA), cytokeratin (CK) and HMB45 antibodies were used to determine the expression of their respective antigens from routine paraffin samples of the patients. RESULTS: Ten patients (7 men and 3 women, aged 31 to 84 years) complained of subcutaneous masses or papular eruptions over their lower trunks and extremities. Histopathologically, the lesions were composed of numerous large round or oval pleomorphic cells. The cytoplasm was usually abundant, amphophilic or basophilic, and finely vacuolated. Nuclei were commonly eccentrically localized and lobated or horseshoed in shape, and multinucleated giant cells and Reed-Sternberg-like cells were seen. Nucleoli were generally multiple and large. Of the 10 patients, tumor cells displayed positive antigen expression of CD30 in all cases, positive CD45RO in 6 cases, positive CD20 in only 1 case, but negative CD45RO and CD20 expressions in 3 cases. Two patients died at 7 weeks and 3.4 years of follow-up, respectively. CONCLUSION: Our study highlights the importance of histopathologic features and positive CD30 staining for differentiation of this disease from other malignant skin tumors.