Apmis

SILVENNOINEN, OLLI; SAHARINEN, PIPSA; PAUKKU, KIRSI; TAKALUOMA, KATI; KOVANEN, PANU

doi: 10.1111/j.1699-0463.1997.tb05047.xpmid: 9269296

Cytokines are the principal regulators of cell proliferation and differentiation of hematopoietic cells and these responses are initiated through activation of hematopoietic cytokine receptors. Although the receptor intracellular domains lack any kinase domains, activation of cytokine receptors lead to rapid induction of tyrosine phosphorylation. Recently, cytokine receptors have been shown to associate with and activate members of the cytoplasmic Jak tyrosine kinase family. Activation of Jak kinases leads to phosphorylation of several signaling proteins and thereby couples ligand‐mediated receptor stimulation to activation of intracellular signaling pathways. The best characterized substrates for Jaks are the Stat transcription factors, which are crucial mediators of cytokine‐mediated gene responses, and, particularly, central determinants for the specificity in cytokine responses.

ROKITA, E.; MENZEL, E. J.

doi: 10.1111/j.1699-0463.1997.tb05048.xpmid: 9269297

The accumulation of sCD14 shed from human monocytes in vivo might correlate with other inflammatory parameters and could be of importance in overcoming a sepsis situation. The development of the sCD14 titer in the supernatant of monocyte‐enriched MNC cultures isolated from healthy volunteers was studied utilizing a commercially available sCD14 ELISA. These culture experiments revealed the prolonged liberation of sCD14 into the supernatant during a period of several days. A medium‐exchange schedule of 2–3 days was found to be superior to a longer incubation period with respect to the sCD14 yield. PMA initially enhanced the CD14 shedding slightly, but after a few hours it strongly repressed the process. Such a reduction was also achieved by protein synthesis inhibitors (cycloheximide, actinomycin D). Additionally, we monitored the concentration of sCD14, CRP, IL‐6 and IL‐8 in human sera from healthy persons or patients suffering from severe burn injuries with or without sepsis. Our results indicate that sCD14 is strongly correlated with IL‐6, but not with IL‐8. sCD14 titers were higher in the group of patients with both burn injuries and sepsis. From experiments with monocyte‐enriched MNC cultures isolated from healthy volunteers and medium supplemented with sera containing sCD14 as well as radiolabeled LPS, we conclude that the enhanced shedding of CD14 in vivo during sepsis is probably not able to reduce the binding of LPS to monocytes.

THORUP, ALIS KARABULUT; DABELSTEEN, ERIK; SCHOU, SØREN; GIL, SUSANA G.; CARTER, WILLIAM G.; REIBEL, JESPER

doi: 10.1111/j.1699-0463.1997.tb05049.xpmid: 9269298

β1 and β4 integrins are receptors on epithelial cells mediating cell‐extracellular matrix adhesion. Furthermore, α2β1 and α3β1 contribute to cell‐cell adhesion. Laminin‐5 in epithelial basement membranes (BMs) is a ligand for α6β4 and α3β1. Expression of different integrins and laminin‐5 was studied in oral epithelium to characterize regional variations in these adhesion molecules. Monoclonal antibodies directed against α2‐α6β1/α6β4 and laminin‐5 were examined in cryopreserved biopsies of normal mucosa by immunohistochemistry. Laminin‐5 was expressed as a line along the BMs. The junctional epithelium showed a unique phenotype: Laminin‐5 was detected in the internal BM at the tooth surface and in the external BM, where excessive laminin‐5 was seen in the stroma. α6β4 was expressed in all cells of the junctional epithelium. Integrins α4β1 and α5β1 were not detected in the epithelia, whereas α2β1 and α3β1 showed differential expression. Epithelia with well‐developed rete pegs and connective tissue papillae showed polarized α3β1 expression along the BM in the rete pegs, in contrast to negative expression at the tips of the connective tissue papillae. A variation in the suprabasal distribution of α2β1 and α3β1 was observed between epithelia from different regions. α2β1 and α3β1 were detected in basal/parabasal cells in keratinized epithelia, whereas there was increased suprabasal expression in nonkeratinized mucosa. These results indicate inhomogeneity in the basal cell population of oral squamous epithelia and differential expression of integrins, which may reflect differences in the underlying stroma. Laminin‐5 deposits in the stroma underneath the junctional epithelium may indicate subclinical gingival inflammation.

RÖNNBLOM, L. E.; PERERS, A.; VALLIN, H. SVENSSON; ERIKSSON, I.; ÖSTERLIND, A.; CEDERBLAD, B.; ALM, G.

doi: 10.1111/j.1699-0463.1997.tb05050.xpmid: N/A

A sensitive dissociation‐enhanced lanthanide fluoroimmunoassay (DELFIA) was evaluated for ability to detect interferon‐α (IFN‐α) in serum of patients with acute infectious disease of less than one week's duration and a fever of >38°C. None of 36 patients with confirmed or probable bacterial disease was IFN‐α positive. In contrast, 13/26 patients with viral infections had detectable levels of IFN‐α in serum, all clearly positive (≥10 U/ml). The IFN‐α positive serum samples were obtained early after onset of clinical disease, after a mean of 2.4 days. The IFN‐α positive samples were obtained from 10 of the 12 patients with influenza or flu‐like infection, and 3 of the 5 patients with varicella or herpes zoster. The IFN‐α negative patients with viral disease (n=9) included five patients with mononucleosis. The DELFIA should be useful in further studies of the value of IFN‐α determinations in the identification of acute viral infections.

VOLDSTEDLUND, MARIANNE; DABELSTEEN, ERIK

doi: 10.1111/j.1699-0463.1997.tb05051.xpmid: 9269300

Most cells express facilitative glucose transporters. Four isoforms (GLUT1‐4) transporting D‐glucose across the plasma membrane show a specific tissue distribution, which is the basis for tissue‐specific patterns in glucose metabolism. GLUT1 is expressed at high levels in tissue barriers such as the blood‐brain barrier, and this isoform has been suggested as an indicator of such barriers. GLUT1 has been found in basal layers of human epidermis where no such tissue barrier is present. To further clarify these issues, we examined the distribution of GLUT1 and GLUT4 in skin, different types of oral mucosa from rat and man, and a human oral careinoma by indirect immunofluorescence microscopy. The results showed that GLUT1 was expressed in the basal and parabasal layers of the different stratified squamous epithelia, with some variations between keratinized and non‐ keratinized subtypes. GLUT1 was also expressed in ductal‐ and myoepithelial cells of minor salivary glands and perineural sheath located in the lamina propra, and furthermore in the cells of an oral careinoma. GLUT4 was not expressed in any of the tissues examined. This distribution of GLUT1 does not fit with the idea of GLUT1 as a general indicator of tissue barriers. In contrast, our results support the prevailing, but limited knowledge of glucose metabolism in squamous stratified epithelia, a metabolism believed to depend mostly on glycolysis, especially in the basal layers. High‐level expression seemed to be confined to keratinocytes without glycogen stores.

KLEMENTSEN, BEATE; JØORGENSEN, LEIF

doi: 10.1111/j.1699-0463.1997.tb05052.xpmid: N/A

The aim of the present study was to obtain information about the distribution of various adhesion molecules within and on the surface of HeLa cells, platelets and endothelial cells in an in vitro model mimicking the early phase of metastasis. Suspensions of HeLa cells and human platelets, added to a medium of cultured human umbilical‐vein endothelial cells, were stimulated by the addition of thrombin. Hirudin was added before thrombin in some experiments, and in other experiments the endothelium was pretreated with 0.5 mM acetylsalicylic acid (ASA). The distribution of platelet‐endothelial cell adhesion molecule (PECAM), P‐selectin, von Willebrand factor (vWf), fibrinogen (FG) and thrombospondin (TSP) was investigated on fixed material from the three experimental settings by using an immunogold electron‐microscopic technique on frozen thin sections. Cells that had not been exposed to thrombin or any other type of stimulation were used as controls. PECAM was the only adhesion molecule detected on HeLa cells. It outlined the membrane on tumour cells that were not adherent to platelets in both basic and hirudin experiments. However, tumour cells in close proximity to activated platelets were unlabelled. In contrast, PECAM was detected on both platelets and endothelium in all experimental settings and in controls. P‐selectin was only demonstrable on platelets in basic experiments. vWf was found both in endothelium and in platelets in controls and in all experimental settings. FG and TSP were found on platelets only, in a manner similar to that seen with vWf. Thus, among the adhesive factors examined in our experimental model, PECAM is the only one demonstrated on HeLa cells. This suggests that PECAM on tumour cells may play a role as adhesion molecule in the early stage of metastasis. P‐selectin, vWf, FG and TSP were also consistently expressed. Therefore, these factors may contribute to the adhesive reactions involved in early metastasis.

THERKILDSEN, MARIANNE HAMILTON; REIBEL, JESPER; SCHIØODT, TORBEN

doi: 10.1111/j.1699-0463.1997.tb05053.xpmid: 9269302

The value of malignancy grading of adenoid cystic carcinomas (ACC) is controversial. Some studies have shown that tumours with a solid growth component have a rapid fatal course, compared to tumours without a solid growth component, in which recurrences develop even many years after initial treatment. Other studies have failed to correlate growth patterns with clinical course. No universally accepted grading system exists and no reproducibility studies of the existing grading systems have been performed. The aim of this study was to examine the reproducibility of grading based on semi‐quantitative assessment of the solid growth pattern in ACC. Two different grading systems were assessed by 3 observers on a material of 59 ACC. Interobserver agreement was evaluated using the kappa statistic. The reproducibility of grading was poor, except for the category “solid component constituting 50% or more of the tumour” (kappa=0.52). It is concluded that quantitative methods are necessary if grading is to be used in prognostic evaluation of ACC. The rarity of the tumours, however, combined with difficulties in diagnosis will impede such investigations unless multicentre studies are undertaken.

KJÆRGAARD, N.; KRISTENSEN, B.; HANSEN, E. S.; FARHOLT, S.; SCHØONHEYDER, H. C.; ULDBJERG, N.; MADSEN, H.

doi: 10.1111/j.1699-0463.1997.tb05054.xpmid: 9269303

The relationship between semen quality, pyospermia and bacteriology was studied in 201 semen specimens from male patients attending a fertility clinic. Semen quality parameters were within normal limits in 115 (57%) patients, slightly reduced in 60 (30%), and 26 (13%) had findings indicating reduced fertility. Twelve patients (6%) had pyospermia. In 182 patients, 552 microorganisms were detected, including Enterobacteriaceae (2.8%), Gardnerella vaginalis (9.6%), Chlamydia trachomatis (1.6%), Mycoplasma genitalium (0.9%), and Ureaplasma urealyticum (11.8%). Semen quality was neither related to occurrence of microorganisms nor pyospermia. However, pyospermia was associated with simultaneous growth of Gardnerella vaginalis and Ureaplasma urealyticum. The exact nature of this association could not be ascertained, in as far as the males were not questioned about urethritis symptoms.

URIBE, ANDRÉES; GUNDERSEN, HANS JØORGEN G.

doi: 10.1111/j.1699-0463.1997.tb05055.xpmid: 9269304

Specimens of antral mucosa were taken from five healthy volunteers and processed for microscopic evaluation. Consecutive 50‐μum‐thick sections were cut to estimate the volume of two antral glands. Two glands in each section were followed throughout by projecting their profiles from two microscopes mounted in parallel. The glandular volume was estimated using Cavalieri's principle. The mean volume of epithelial cells was estimated by systematic random sampling of the sections with an optical disector of known sample volume. The total number of cells per gland was calculated after determination of the volume of the glands and the mean volume of the epithelial cells. The mean volume of the antral glands was 13.6±1.67 106μum3, whilst the mean volume of the epithelial cells was 1256±240 μum3. The total number of epithelial cells per gland was 11216±1104. In conclusion, using stereological methods, the total number of cells as well as the cell volume and the volume of antral glands can be determined in routine biopsy specimens of human stomach provided that the total depth of the mucosa is present in the section.

LANDBERG, GÖORAN; ROOS, GÖORAN

doi: 10.1111/j.1699-0463.1997.tb05056.xpmid: 9298094

Breast cancer is a heterogeneous disease regarding morphology, invasive behavior, metastatic capacity, hormone receptor expression and clinical outcome. For prediction of prognosis, tumor cell kinetics is an important feature, traditionally evaluated by estimation of cell growth‐associated parameters such as mitotic index, S‐phase fraction and expression of proliferation coupled proteins, for example proliferating cell nuclear antigen (PCNA) and Ki‐67 antigen. Recent data indicate that deregulation of the cell cycle can occur at different levels in cancer and that the “deregulation pattern” can be of clinical significance. In the present overview we give a short description of approaches used for cell proliferation assessments, whereafter more recent data on cell cycle deregulation are discussed. Alterations of importance in breast cancer include overexpression of cyclins D1 and E, down‐regulation of cyclindependent kinase inhibitors, such as p16, and inactivation of the retinoblastoma and p53 tumor suppressor proteins.