Flagellin hypervariable region determines symbiotic properties of commensal Escherichia coli strains

Escherichia coli represents a classical intestinal gram-negative commensal. Despite this commensalism, different E. coli strains can mediate disparate immunogenic properties in a given host. Symbiotic E. coli strains such as E. coli Nissle 1917 (EcN) are attributed beneficial properties, e.g., promotion of intestinal homeostasis. Therefore, we aimed to identify molecular features derived from symbiotic bacteria that might help to develop innovative therapeutic alternatives for the treatment of intestinal immune disorders. This study was performed using the dextran sodium sulphate (DSS)-induced colitis mouse model, which is routinely used to evaluate potential therapeutics for the treatment of Inflammatory Bowel Diseases (IBDs). We focused on the analysis of flagellin structures of different E. coli strains. EcN flagellin was found to harbor a substantially longer hypervariable region (HVR) compared to other commensal E. coli strains, and this longer HVR mediated symbiotic properties through stronger activation of Toll-like receptor (TLR)5, thereby resulting in interleukin (IL)-22–mediated protection of mice against DSS-induced colitis. Furthermore, using bone-marrow–chimeric mice (BMCM), CD11c+ cells of the colonic lamina propria (LP) were identified as the main mediators of these flagellin-induced symbiotic effects. We propose flagellin from symbiotic E. coli strains as a potential therapeutic to restore intestinal immune homeostasis, e.g., for the treatment of IBD patients.

A flagellum renders bacteria motile, but this study reveals another property important for symbiosis: the hypervariable region of Escherichia coli flagellin strongly determines activation of TLR5, mediating benefits for the host such as protection against colitis.

Phytotherapie in der Dermatologie: Übersicht zur Heilpflanzenverwendung in der Dermatologie und zu ihrer Verfügbarkeit als Fertigarzneimittel

Obwohl Erkrankungen aus dem dermatologischen Spektrum häufig in der allgemeinmedizinischen und auch naturheilkundlichen Sprechstunde vorkommen, gibt es nur wenig zugelassene Fertigpräparate für Hauterkrankungen. In den Bewertungen der HMPC-Monografien wird häufig nur ein sog. „traditional use“ als Einschätzung vergeben. Nur selten werden Präparate aus dem dermatologischen Einsatzgebiet als „well-established“ eingestuft.

Um die Zahl an wissenschaftlich getesteten, zugelassenen Phytotherapeutika zu erhöhen, bedarf es einer vermehrten Forschungstätigkeit auf diesem Gebiet. Neben den von Pharmafirmen initiierten und finanzierten Studien sollte auch auf universitärer Ebene von pharmakologischer und dermatologischer Seite ein Interesse an der Förderung von phytotherapeutisch-dermatologischen Forschungen bestehen. Nur so könnte die Anzahl der unter wissenschaftlichen Gesichtspunkten getesteten Phytopharmaka für das Gebiet der Dermatologie erhöht werden.

Characterization of different courses of atopic dermatitis in adolescent and adult patients

BACKGROUND

Atopic dermatitis (AD) starts most often during the first years of life and goes into remission in a high proportion of cases during childhood. However, in severe cases, AD persists until adulthood or starts and relapses later in life. So far, studies investigating the natural course of AD during adolescence and adulthood are rare. The aim of our study was to classify different courses of AD and to correlate these with specific risk factors for severe variants of AD.

METHODS

A detailed clinical examination and retrospective evaluation of the history of the disease were performed in a collective of 725 adolescent and adult patients with AD. Laboratory data including total and specific IgE were evaluated.

RESULTS

Six hundred and seven patients of 725 patients could be classified into course types. Of these 607 patients 85.7% could be classified into five main different course types of all 31 course types recorded. The highest differences in the number of sensitizations, total immunoglobulin E serum levels and predilection of the skin lesions were observed between patients with an early type of onset of AD and a chronic persisting course until adulthood and patients with a late type of onset of AD, that is, after the 20th year of life.

CONCLUSION

Our data show that the natural course of AD can be divided into subgroups that display different clinical features. The data support the assumption of a broad heterogeneity of AD in adolescence and adulthood and emphasize the future need for careful stratification of patients with AD.

Human ovarian surface epithelial cells immortalized with hTERT maintain functional pRb and p53 expression

OBJECTIVE

Cell immortalization is considered to be a prerequisite status for carcinogenesis. Normal human ovarian surface epithelial (OSE) cells, which are thought to be the origin of most of human ovarian carcinomas, have a very limited lifespan in culture. Establishment of immortalized OSE cell lines has, in the past, required inactivation of pRb and p53 functions. However, this often leads to increased chromosome instability during prolonged culture.

MATERIALS AND METHODS

In this study, we have used a retroviral infection method to overexpress human telomerase reverse transcriptase (hTERT) gene, in primary normal OSE cells, under optimized culture conditions.

RESULTS

In vitro and in vivo analysis of hTERT-immortalized cell lines confirmed their normal epithelial characteristics. Gene expression profiles and functional analysis of p16(INK4A), p15(INK4B), pRb and p53 confirmed the presence of their intact functions. Our study suggests that inactivation of pRb and p53 is not necessary for OSE immortalization. Furthermore, down-regulation of p15(INK4B) in the immortalized cells may indicate a functional role for this protein in them.

CONCLUSION

These immortal OSE cell lines are likely to be an important tool for studying human OSE biology and carcinogenesis.

[Associated diseases and differential diagnostic considerations in childhood atopic eczema]

Atopic eczema (AE) is a chronic inflammatory skin disease which affects 10 to 20% of children and 1 to 3% of adults. AE is usually diagnosed based on standard criteria such as those of Hanifin and Rajka, whereby the age-related variation must be considered. There are numerous other diseases which go along with AE or show a very similar clinical picture and represent important differential diagnostic considerations including parasitic diseases, immunodeficiency, nutritional diseases, certain neoplastic disorders and various corneal abnormalities. Additionally, it is important to consider diseases which can occur in association with AE, such as keratosis pilaris, alopecia areata or sweat disturbances.

Putative association of a TLR9 promoter polymorphism with atopic eczema

BACKGROUND

Toll-like receptors (TLR) play a pivotal role in the induction of first-line defense mechanisms of the innate immune system and trigger adaptive immune responses to microbial pathogens. Genetic variations in innate immunity genes have been reported to be associated with a range of inflammatory disorders. Deficiencies on the level of immunity receptors such as pathogen-recognition receptors are suspected to affect the maturation of our immune system and to avail thereby the high prevalence of atopic diseases and susceptibility of atopic patients to microbial infections.

AIMS OF THE STUDY

We evaluated TLR9 as susceptibility gene for atopic eczema (AE).

METHODS

Analyses of four tag single-nucleotide polymorphisms in two panels of families containing a total of 483 parent-affected offspring trios as well as a cohort of 274 unrelated adult AE cases and 252 hypernormal population-based controls have been performed.

RESULTS

In both family cohorts, polymorphism C-1237T, which is located within the promoter region of the TLR9 gene, was significantly associated with AE, in particular the intrinsic subtype of AE. No associations were seen in the case-control cohort. Luciferase reporter gene assays revealed significantly higher promoter activity of the TT allelic variant at this single nucleotide polymorphism site.

CONCLUSION

These observations suggest that the TLR9 promoter polymorphism C-1237T might affect AE susceptibility in particular in patients with the intrinsic variant of AE.

Molecular profiling of cervical cancer progression

Most cancer patients die of metastatic or recurrent disease, hence the importance to identify target genes upregulated in these lesions. Although a variety of gene signatures associated with metastasis or poor prognosis have been identified in various cancer types, it remains a critical problem to identify key genes as candidate therapeutic targets in metastatic or recurrent cancer. The aim of our study was to identify genes consistently upregulated in both lymph node micrometastases and recurrent tumours compared to matched primary tumours in human cervical cancer. Taqman Low-Density Arrays were used to analyse matched tumour samples, obtained after laser-capture microdissection of tumour cell islands for the expression of 96 genes known to be involved in tumour progression. Immunohistochemistry was performed for a panel of up- and downregulated genes. In lymph node micrometastases, most genes were downregulated or showed expressions equal to the levels found in primary tumours. In more than 50% of lymph node micrometastases studied, eight genes (AKT, BCL2, CSFR1, EGFR1, FGF1, MMP3, MMP9 and TGF-beta) were upregulated at least two-fold. Some of these genes (AKT and MMP3) are key regulators of epithelial-mesenchymal transition in cancer. In recurrent tumours, almost all genes were upregulated when compared to the expression profiles of the matched primary tumours, possibly reflecting their aggressive biological behaviour. The two genes showing a consistent downregulated expression in almost all lymph node metastases and recurrent tumours were BAX and APC. As treatment strategies are very limited for metastatic and recurrent cervical cancer, the upregulated genes identified in this study are potential targets for new molecular treatment strategies in metastatic or recurrent cervical cancer.

Successful treatment of acrodermatitis continua suppurativa with topical tacrolimus 0.1% ointment

Acrodermatitis continua suppurativa of Hallopeau (ACS) is a rare pustular variant of psoriasis in which numerous treatment modalities have been used without any consistent long-term effect. We report for the first time two patients with ACS which was successfully treated with topical tacrolimus 0.1% ointment. Our observations raise hopes that this new treatment strategy for ACS may constitute a novel effective therapeutic option for this recalcitrant condition.

[Somatization and alexithymia in male infertility. A replication study]

BACKGROUND AND OBJECTIVE

In a previous study, we found a higher degree of alexithymia and somatization in infertile men (Hum Reprod 2001 Vol.16(3),587-592). This study was designed to confirm the findings of the former study

PATIENTS/METHODS

88 infertile men (48 idiopathic infertility, 40 somatic infertility) were consecutively enrolled in the study. The control group consisted of 44 healthy men. Alexithymia was measured by the 20-item-Toronto-Alexithymia-Scale;somatization was measured by the Symptom Checklist-90-R.

RESULTS

There were no differences between the subgroups of infertile men. The study group showed a significantly higher sum score in the TAS-20 (p<0.01) and a higher score on the scale somatization in the Symptom Checklist-90-R (p<0.05) compared to the control group.

CONCLUSIONS

Our study replicated the findings of the previous investigation. Alexithymia and somatization are discussed as consequences of coping with male infertility.

Procalcitonin: a useful discriminator between febrile conditions of different origin in hemato-oncological patients?

Plasma concentrations of procalcitonin (PCT) have been shown to be elevated in bacterial and fungal infections. In contrast to C-reactive protein (CRP), PCT is not elevated in inflammations of noninfectious origin. Febrile inflammatory conditions are frequent in patients with hemato-oncological diseases. A reliable marker to discriminate infectious inflammations from drug-related and tumor-associated fever is still lacking. To evaluate the impact of PCT in this setting, PCT and CRP were prospectively measured in 95 febrile hemato-oncological patients. Infections could be identified in 40 of 95 patients: 38 of 95 had fever of unknown origin (FUO), 9 patients were suspected to suffer from drug-related fever, and 8 patients from tumor-associated fever. In the noninfection group (drug-related and tumor-associated fever), PCT levels were significantly lower than in patients with infections (P<0.001) or FUO (P<0.001). Differences were still highly significant comparing patients with suspected drug-related or tumor-associated fever alone with the infection or the FUO cohort. All eight patients with tumor-associated fever as well as eight of the nine patients with drug-related fever had PCT levels within the normal range (<0.5 micro g/l). CRP values only partially allowed discrimination between the various subgroups. Differences were significant between patients with drug-related fever and the infection (P=0.001) or FUO group (P=0.004). However, as CRP levels were far above the normal range also in the patients with drug-related fever, the significance of individual values was rather limited. In conclusion, PCT may provide useful additional information to assess the clinical significance of febrile conditions. PCT may facilitate the decision on when to initiate antimicrobial or cytotoxic therapy.

mRNA expression of matrix metalloproteases and their inhibitors differs in subtypes of renal cell carcinomas

Altered expression of matrix metalloproteases (MMPs) and their inhibitors, the tissue inhibitors of matrix metalloproteases (TIMPs), has been demonstrated in various tumour tissues. mRNA expression patterns of MMP-1, MMP-2, MMP-3, MMP-9, MMP-11, MMP-12, MMP-14 and TIMP-1, TIMP-2, TIMP-3 and TIMP-4 were evaluated by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) in 30 renal cell carcinomas (RCC), as well as in the surrounding tissues. Expression of the MMPs was significantly stronger in the carcinomas than in non-malignant tissues. High levels were demonstrated particularly in clear cell RCCs (CC-RCC). Except for MMP-1, MMP expression in the papillary RCCs (P-RCC) was, for most MMPs, significantly lower. Expression of the TIMPs in malignant cells of both subtypes was weak, with the exception of TIMP-4 which was strongly expressed in the P-RCCs and downregulated in the CC-RCCs. The latter was correlated with chromosomal loss of 3p, harbouring the TIMP-4 gene locus. In conclusion, deregulated expression of the MMPs and TIMPs in RCCs differs according to histology, grade, size and cytogenetic characteristics, suggesting that MMP and TIMP expression patterns play an important role for the typical histomorphological features of RCC subtypes and their respective biological behaviour.

Deletion within the Src homology domain 3 of Bruton's tyrosine kinase resulting in X-linked agammaglobulinemia (XLA)

The gene responsible for X-linked agammaglobulinemia (XLA) has been recently identified to code for a cytoplasmic tyrosine kinase (Bruton's agammaglobulinemia tyrosine kinase, BTK), required for normal B cell development. BTK, like many other cytoplasmic tyrosine kinases, contains Src homology domains (SH2 and SH3), and catalytic kinase domain. SH3 domains are important for the targeting of signaling molecules to specific subcellular locations. We have identified a family with XLA whose affected members have a point mutation (g-->a) at the 5' splice site of intron 8, resulting in the skipping of coding exon 8 and loss of 21 amino acids forming the COOH-terminal portion of the BTK SH3 domain. The study of three generations within this kinship, using restriction fragment length polymorphism and DNA analysis, allowed identification of the mutant X chromosome responsible for XLA and the carrier status in this family. BTK mRNA was present in normal amounts in Epstein-Barr virus-induced B lymphoblastoid cell lines established from affected family members. Although the SH3 deletion did not alter BTK protein stability and kinase activity of the truncated BTK protein was normal, the affected patients nevertheless have a severe B cell defect characteristic for XLA. The mutant protein was modeled using the normal BTK SH3 domain. The deletion results in loss of two COOH-terminal beta strands containing several residues critical for the formation of the putative SH3 ligand-binding pocket. We predict that, as a result, one or more crucial SH3 binding proteins fail to interact with BTK, interrupting the cytoplasmic signal transduction process required for B cell differentiation.

A new RFLP marker, SP282, at the btk locus for genetic analysis in X-linked agammaglobulinaemia families

X-linked agammaglobulinaemia is an inherited recessive disease in which the primary defect lies in the failure of pre-B cells to develop into mature circulating B cells, due to a defective B-cell cytoplasmic tyrosine kinase (btk). For this study we introduced a new RFLP marker, SP282, which is tightly linked to the XLA locus. In conjunction with the marker DXS178, SP282 was used to identify a carrier female and predict her male offspring to be normal. Subsequently the fetus was shown to have a normal number of circulating B cells, and at 2.5 years of age, the non-affected phenotype of the child was confirmed.

Physical mapping in a YAC contig of 11 markers on the human X chromosome in Xp11.23

By using yeast artificial chromosome (YAC) clones, we have generated a physical map of the short arm of the human X chromosome at Xp11.23. The region analyzed spans the distal marker UBE1 and the ARAF1/TIMP/SYN1/PFC gene cluster and further extends proximally to include ELK1, ZNF21, ZNF81, and OATL1 in a single contig. We have uniquely placed UBE1 and the SYN1 gene cluster in a 330-kb YAC within the contig. In addition, the genes SYP and TFE3 are physically linked in a YAC of 400 kb from the more centromeric portion of Xp11.23. We have refined the map by using fragmentation vectors to generate YAC deletion derivatives. These derivatives show that ZNF81 and ZNF21 lie within an approximately 130-kb segment and that SYN1.2 and ELK1 are less than 50 kb apart. Together these data reveal the following order for the markers in this region: Xpter-UBE1-ARAF1-TIMP-SYN1.2-PFC-ELK1++ +-ZNF81-ZNF21-OATL1-(SYP,TFE3)-Xcen.

Localization of the gene for the Wiskott-Aldrich syndrome between two flanking markers, TIMP and DXS255, on Xp11.22-Xp11.3

The Wiskott-Aldrich syndrome (WAS) is an X-linked recessive genetic disease in which the basic molecular defect is unknown. We previously located the WAS gene between two DNA markers, DXS7 (Xp11.3) and DXS14 (Xp11), and mapped it to the proximal short arm of the human X chromosome (Kwan et al., 1988, Genomics 3:39-43). In this study, further mapping was performed on 17 WAS families with two additional RFLP markers, TIMP and DXS255. Our data suggest that DXS255 is closer to the WAS locus than any other markers that have been previously described, with a multipoint maximum lod score of Z = 8.59 at 1.2 cM distal to DXS255 and thus further refine the position of the WAS gene on the short arm of the X chromosome. Possible locations for the WAS gene are entirely confined between TIMP (Xp11.3) and DXS255 (Xp11.22). Use of these markers thus represents a major improvement in genetic prediction in WAS families.