Novel monoclonal antibodies against mouse C3 interfering with complement activation: description of fine specificity and applications to various immunoassays

The role of complement proteins in various pathophysiological settings has been studied primarily using mouse models of disease. However, the specific contribution of C3-derived fragments to these biologic processes has not been addressed in a rigorous manner because of a lack of antibodies that can selectively recognize mouse C3 or any of its degradation fragments. Here we report the generation and characterization of a panel of rat monoclonal antibodies reacting with mouse C3 and its degradation products. We describe their performance in various immunological assays such as ELISA, Western blotting, flow cytometry and immunohistochemistry. Of all the antibodies generated, one selectively recognized the C3a anaphylatoxin, and all other reacted with C3c. Furthermore, two monoclonal antibodies preferentially reacted with the cleaved C3 fragments C3b/iC3b/C3c but not native C3. Except for the one recognizing C3a, all antibodies were suitable for detecting C3 deposited on cells and tissues, two effectively inhibited the hemolytic activity of mouse complement and one enhanced C3-deposition to the cell membrane. These novel monoclonal antibodies may serve as useful reagents for elucidating functions mediated by C3-derived fragments in various pathophysiological conditions.     

Cystatin C is a suitable marker of glomerular function in children with cancer

Antineoplastic chemotherapy is associated with nephrotoxic side effects. Data on nephrotoxicity in childhood cancer are scanty, in part because of the difficulties in obtaining reliable markers of glomerular function. We used serum cystatin C (cysC) to assess glomerular function. CysC was compared with serum creatinine concentration (S_Cr), the endogenous creatinine clearence ( C _Cr), and the calculated Counahan formula ( C _Counahan) in children with leukemia and solid tumors. CysC was measured by particle-enhanced immunoturbidimetric assay. Serum and urinary creatinine concentrations were determined by the Jaffé method. Samples were obtained from 258 children, including 92 receiving anticancer chemotherapy, 108 long-term survivors, 40 children without any renal disease, and 18 patients with chronic renal insufficiency. CysC of patients on current chemotherapy was assessed both before and after treatment. Significant correlations were found between cysC and S_Cr and between 1/cysC and C _Counahan. CysC increased significantly after cisplatin, methotrexate, cyclophosphamide, ifosfamide, and multimodality treatment. Our results suggest that cysC measurement can be used to characterize glomerular function in children with cancer.     

Expression of dentin matrix protein 1 (DMP1) in nonmineralized tissues

Dentin matrix protein 1 (DMP1) is an Arg-Gly-Asp-containing acidic phosphoprotein that was originally identified from a rat incisor cDNA library and was thought to be a dentin-specific protein. DMP1 was later shown to express in a number of hard tissue-forming cells, including osteoblasts, osteocytes, ameloblasts, and cementoblasts, and was considered to play important roles in mineralization. Further, DMP1 gene expression was also detected in fetal bovine brain and in newborn mouse brain. These findings indicate the possibility of DMP1 expression in other soft tissues. In the present study, to clarify the significance of DMP1 expression in nonmineralized tissues, we made a specific antibody to mouse DMP1 peptides and demonstrated that DMP1 protein was localized in mouse brain, pancreas, and kidney by immunohistochemistry. Further DMP1 mRNA was detected in nonmineralized mouse tissues including liver, muscle, brain, pancreas, and kidney by RT-PCR. Based on the evidence that the localization and the expression of DMP1 are not restricted to mineralized tissues, we assume that DMP1 may have functions other than the regulation of mineralization.     

Comparison between angiographic right coronary artery motion and echocardiographic tricuspid annulus motion

OBJECTIVE: To compare echocardiographic M-mode measurements of tricuspid annulus motion (TAM) with angiographic M-mode measurements of right coronary artery motion (RAM). DESIGN: Twenty-four patients were included and examined by echocardiography before the angiographic examination. The amplitudes and the velocities of TAM and the atrial contribution to the total amplitude of TAM were measured. The obtained values were compared with angiographic M-mode measurements of RAM at a proximal and a distal site of the second segment of the right coronary artery. RESULTS: There was no significant difference between several of the echocardiographic M-mode measurements of TAM and the angiographic M-mode measurements of RAM. However, the agreement was rather poor for some variables. CONCLUSION: Different parameters obtained from echocardiographic TAM are not interchangeable with values from angiographic RAM. If measurements of RAM are to be used in the assessment of right ventricular (RV) function further studies are needed to examine the correlation and agreement between RAM and different methods of measuring RV function, i.e. radionuclide angiography or magnetic resonance imaging.     

The role of VATS in the diagnosis and treatment of mediastinal masses

We performed 158 operations for mediastinal lesions in general anaesthesia from 1st December 1995 to 31st May 2004 using video assistance. Among them 105 procedures were diagnostic and 53 therapeutic. There was no mortality and no serious complications. We believe that VATS technique provides a big help in the diagnosis of mediastinal diseases and in the treatment of the benign lesions. It is a responsible safe method and causes less stress for the patients.     

Diverse expression of the K-1 antigen by cortico-medullary and reticular epithelial cells of the bursa of Fabricius in chicken and guinea fowl

The immunocytochemical study of the K-1 monoclonal antibody indicates that the epithelial components of the bursa of Fabricius of the chicken and guinea fowl express the K-1 positive molecule. During embryogenesis, the K-1 antigen expression appears together with the bud-formation. As the number of B cells increases in the developing follicle, the K-1 expression gradually diminishes in the medullary reticular epithelial cells and completely ceases by hatching, which suggests that the molecule is developmentally regulated. After hatching, the expression of the molecule is restricted to the sealing off zone of the lymphoepithelial or medullary region of the follicle: i.e. to the cortico-medullary (CM) epithelial cells and the follicle associated epithelium (FAE) supporting cells in guinea fowl and to the latter ones in the chicken. The expression of the K-1 antigen by these epithelial components may support their structural identity. After hatching, the K-1 molecule is restricted to the CM epithelial cells and/or FAE supporting cells, which suggests that the function of the embryonic epithelial bud is taken over by the CM epithelial cells. The K-1 positive CM epithelial cells form arches, which encompass blast-like cells. The possible relationship of the CM epithelial cells and blast-like cells, which may represent the precursors of bursal secretory dendritic cells is discussed.     

Current possibilities in the treatment of infected pancreatic necrosis

This is a retrospective study about 80 patients treated for infected necrosis of the pancreas between 1998-2003. Operation was performed in 74 patients, diagnosis was achieved by CT or U.S. guided drainage in 12 patients. In further 6 patients drainage and antibiotic therapy provided cure. In patients who were drained pre-operatively (n=12) the first surgical intervention was performed on average on the 30.2 days after admission, while in the group of patients without drainage surgery became necessary after 15.6 days. The difference is statistically significant (p = 0.001). Our data proved that in certain cases percutaneous drainage can delay surgical intervention. Our results also prove that percutaneous drainage itself can lead to complete cure. In our own practice this stands for about 20% of our patients. In 3 patients we proved that if the patients general condition is stable infected necrosis detected by fine needle aspiration can be successfully treated by antibiotic therapy, without surgical or further radiological intervention.