Secretion of cytokines by uroepithelial cells stimulated by Escherichia coli and Citrobacter spp.

Urinary tract epithelial cells (T 24/83) are able to express interleukin (IL)-6, IL-8, platelet-derived growth factor (PDGF) and tumour necrosis factor-alpha, but not IL-1 beta, IL-2, IL-4 and IL-10 in response to an infection with uropathogenic bacteria. The process of cytokine secretion is time dependent, with a significant increase in the cytokine activity after 60 min. The expression of virulence factors of the bacteria does not seem to play a role. The interaction between bacterial products (e.g. lipopolysaccharide) and/or bacterial adhesion mediated by adhesins and specific receptor molecules of cell surfaces may be responsible for the activity of mediator protein expression in the epithelial cells. The release of PDGF and IL-8 was found to be higher when due to Escherichia coli HB 101 (rough form) than that caused by other bacterial strains. Citrobacter CB 3009 provoked the highest level of IL-6. The PDGF level correlated significantly with IL-6 and IL-8 values (P<0.001). There was a significant correlation between the time-dependent release of IL-6 and IL-8 (P<0.05). In epithelial cytokine response to bacterial infection, the reaction of the epithelial cells may modify themselves (e.g. internalization of bacteria) and the immuno-regulatory processes that are caused by infection and responsible for parenchymal injury.

Internalization of extraintestinal Escherichia coli O18 strains by epithelial cells is modulated by EGF, insulin, and effectors of transmembrane signal transduction.

Adhesion to and internalization into host cells is an essential step in the pathogenesis of various bacterial infections. Here we investigated the effects of growth factors on the internalization of Escherichia coli O18 strains isolated from patients with urinary tract infection (UTI) by human epithelial cells. A dramatic increase in the uptake of Escherichia coli was observed after treatment of epithelial cells with epidermal growth factor (EGF) and to a lower extent with insulin. EGF-dependent internalization can be suppressed by tyrosine kinase inhibitors suggesting an involvement of the receptor tyrosine kinases in the regulation of the endocytotic process. Inhibitors of phospholipase A2, lipoxygenase, and cyclooxygenase significantly decreased internalization of bacteria induced by EGF. Finally, the specific inhibitor of PI 3-kinases Wortmannin was shown to suppress completely the EGF-independent internalization. The data of this analysis indicate the involvement of several signaling paths in bacterial internalization of uropathogenic Escherichia coli O18 strains and contribute to the comprehension of the pathogenesis of recurrent UTI.

[Lymphocyte transformation test (LTT) as a model for evaluating cytokine-induced immunomodulation in renal cell carcinoma]. / Lymphozytentransformations-test (LTT) als Modell zur Uberprüfung der zytokinvermittelten Immunmodulation beim Nierenzellkarzinom.

We investigated the immunomodulatory capacity of cytokines produced by renal cell carcinoma in vitro by analyzing their effects on mitogen-induced T-lymphocyte blast cell transformation. All of the tested 70 cell cultures, derived from 70 tumor areas in 33 patients, had immunomodulatory capacity. In addition to suppression in the lymphocyte transformation test (max. 44/70; 63%) there was also superinduction (max. 37/70; 53%). We found no significant correlation with the stage and grade of primary tumors. However, the suppression of mitogen-induced T-lymphocyte blast cell transformation was significant in multifocal tumors (0.08% TCM, P < 0.001) and non-significant in metastatic tumors. The production of the assayed cytokines IL-6, IL-10, IL-11, and TGF beta 1 was variable and there was no significant correlation to the immunomodulatory capacity of the tumors.

Serum transforming growth factor-beta1 in patients with renal cell carcinoma.

PURPOSE: A major problem of renal cell carcinoma is the prediction of metastases via tumor prognostic markers. Therefore, much effort has been committed to the development of new prognostic markers. MATERIALS AND METHODS: The level of transforming growth factor-beta1 was measured by enzyme-linked immunosorbent assay in serum samples collected from patients with renal cell carcinoma before radical nephrectomy. RESULTS: In serum samples from 21 patients with renal cell carcinoma and 21 healthy controls mean transforming growth factor-beta1 levels were 177 +/- 54.1 versus 65.6 +/- 15.8 ng./ml., respectively. This difference was statistically significant (Mann-Whitney U test p <0.001). CONCLUSIONS: Increased levels of transforming growth factor-beta1 are common in serum of patients with renal cell carcinoma.

Cytogenetic, histopathologic, and immunologic studies of multifocal renal cell carcinoma.

BACKGROUND: Multifocal tumor areas occurred in 12-22% of patients with renal cell carcinoma. It is unknown whether these tumors have malignant potential and characterize a higher risk for metastases. The performance of nephron-sparing surgery in patients with low grade or low stage tumors is controversial. METHODS: Primary and secondary tumors were analyzed by conventional cytogenetics and fluorescence in situ hybridization. Production of interleukin (IL)-6, IL-10, IL-11, and transforming growth factor (TGF)-beta1 were determined using standard enzyme-linked immunosorbent assay and bioassays. RESULTS: In 15.2% of the renal cell carcinoma cases evaluated, multifocal tumors were detected. Cytogenetics revealed a concordance of primary and secondary tumors in 9 of 14 cases (64%). In 11 of 12 multifocal tumors (94%), the same immunologic activity status was observed in both primary and secondary tumors. CONCLUSIONS: Secondary tumors must be expected to have malignant potential similar to that of the primary tumors. This was underscored by the high concordance of cytogenetic, histopathologic, and immunologic data in this study.

[Primary culture of different renal cell carcinoma cells with respect to immunomodulatory effects]. / Untersuchungen von Primärkulturen verschiedener Nierenzellkarzinome (NZK) in Hinblick auf immunmodulatorische Effekte.

The presented results show that renal cell carcinomas (RCC) have partial immunomodulatory capacity (production of cytokines as IL-6, -10, -11; modulation of mitogen-induced transformation of T lymphocytes). The production of IL-10 shows a tendency to correlate with higher staging and grading of RCC. The cytokine production does not correlate with specific types of RCC. Direct immunosuppression of T lymphocytes in lymphocyte transformation tests (LTT) was not detectable.

Cystatin A-like immunoreactivity is widely distributed in human brain and accumulates in neuritic plaques of Alzheimer disease subjects.

The cellular localization of cystatin A, an endogenously occurring inhibitor of lysosomal thiol proteases (cathepsins B, H, L and S), was studied immunohistochemically in human postmortem brain using the peroxidase-antiperoxidase method. Both polyclonal and monoclonal antibodies to cystatin A were employed. Western blot analysis revealed one molecular form of the inhibitor in human brain extracts. Its molecular weight was about 13,000. Immunostaining appeared in a sizeable population of neurons and a few cells surrounding cerebral blood vessels (pericytes). In Alzheimer disease subjects cystatin A was found in many neuritic plaques. Possible functional consequences with regard to a role of cystatin A in the inhibition of the Alzheimer amyloid precursor protein (APP)-clipping enzyme, cathepsin B, are discussed.

Substance P, mean apnoea duration and the sudden infant death syndrome (SIDS).

In order to evaluate disturbances of the respiratory control in the first year of life in children with a statistically enhanced risk of SIDS, substance P-like immunoreactivity (SPLI) in plasma and mean apnoea duration (MA) were examined. 4 groups of infants were investigated: Controls, full-term infants with anamnestic SIDS-risk factors, preterm infants with additional risk factors and preterm infants without such factors. Infants aged from -4(corrected age) to 63 weeks. SPLI in plasma was determined by a specific, homologous radioimmunoassay. The SPLI-level was significantly higher in controls (n = 41; means +/- SE = 36.37 +/- 4.86 pg/ml) than in preterm infants without (n = 21; 25.41 +/- 5.54 pg/ml) or with additional anamnestic risk factors (n = 111; 25.89 +/- 3.09 pg/ml). SPLI was higher in full-term SIDS-risk infants (n = 150; 30.73 +/- 2.35 pg/ml) than in the preterm groups. There is a significant age dependence in the groups full-term SIDS-risk infants and preterm infants with additional risk factors. During maturation the SPLI-level in plasma rises in these groups from lower values. The MA-values were determined by means of a daytime polygraphy. There is an age dependence of the MA-values during active sleep in full-term SIDS-risk infants and in preterm infants with additional anamnestic risk factors. In the age group 4-17 weeks (peak of SIDS frequency) in active sleep the MA-values were significantly higher in all 3 risk groups than in the controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Cystatin C containing neurons in human postmortem hypothalamus.

The regional distribution and cellular localization of cystatin C in neurons of human postmortem hypothalamic was studied by use of peroxidase-anti-peroxidase technique. Cystatin C (earlier named gamma-trace) was found to be present in multiple nerve cells belonging to nuclei supraopticus, paraventricularis and arcuatus. We speculate that the occurrence of cystatin C in human cerebrospinal fluid is the result of a release of the protein from these neurons into the ventricular system.