IL-17C mediates the recruitment of tumor-associated neutrophils and lung tumor growth

Chronic obstructive pulmonary disease (COPD) is associated with an increased risk for lung cancer and an aberrant microbiota of the lung. Microbial colonization contributes to chronic neutrophilic inflammation in COPD. Nontypeable Haemophilus influenzae (NTHi) is frequently found in lungs of stable COPD patients and is the major pathogen triggering exacerbations. The epithelial cytokine interleukin-17C (IL-17C) promotes the recruitment of neutrophils into inflamed tissues. The purpose of this study was to investigate the function of IL-17C in the pulmonary tumor microenvironment. We subjected mice deficient for IL-17C (IL-17C^-/-) and mice double deficient for Toll-like receptor 2 and 4 (TLR-2/4^-/-) to a metastatic lung cancer model. Tumor proliferation and growth as well as the number of tumor-associated neutrophils was significantly decreased in IL-17C^-/- and TLR-2/4^-/- mice exposed to NTHi. The NTHi-induced pulmonary expression of IL-17C was dependent on TLR-2/4. In vitro, IL-17C increased the NTHi- and tumor necrosis factor-α-induced expression of the neutrophil chemokines keratinocyte-derived chemokine and macrophage inflammatory protein 2 in lung cancer cells but did not affect proliferation. Human lung cancer samples stained positive for IL-17C, and in non-small cell lung cancer patients with lymph node metastasis, IL-17C was identified as a negative prognostic factor. Our data indicate that epithelial IL-17C promotes neutrophilic inflammation in the tumor microenvironment and suggest that IL-17C links a pathologic microbiota, as present in COPD patients, with enhanced tumor growth.

Sex mismatch in heart transplantation is associated with increased number of severe rejection episodes and shorter long-term survival

BACKGROUND

Heart transplantation is the criterion standard for treating end-stage heart failure. Male sex of both the donor organ and the recipient is advantageous for survival, possibly owing to hemodynamic or immunologic reasons. The effect of sex mismatch on long-term survival in male heart transplant recipients is less known.

PATIENTS AND METHODS

In this prospective single-center study, we reviewed follow-up data for 57 sex-mismatched and 179 sex-matched men who underwent orthotopic heart transplantation between 1990 and 2002.

RESULTS

Median survival was significantly shorter in the sex-mismatched group (8.1 vs 12.9 years; P < .04). Subgroup analysis revealed that this was even more pronounced in male heart recipients with coronary artery disease (2.4 vs 12.9 years; P < .001). Female donor organs were significantly smaller (left ventricular end-diastolic diameter 49 vs 51 mm; P < .05), and recipients more often experienced clinically relevant episodes of cellular rejection during the first 3 months posttransplantation (International Society for Heart and Lung Transplantation grade 3, 5.6% vs 3.1%; P < .001). Global left ventricular function, and immunosuppressive and inflammatory parameters did not differ.

CONCLUSION

In male orthotopic heart transplant recipients, sex mismatch is associated with adverse outcome owing to increased number and severity of episodes of graft rejection.

Expression of tight and adherens junction proteins in ulcerative colitis associated colorectal carcinoma: upregulation of claudin-1, claudin-3, claudin-4, and beta-catenin

BACKGROUND

Tight junction (TJ) proteins play a critical role in cellular adhesion, glandular differentiation, and cellular proliferation. The function of these proteins is compromised in a number of intestinal diseases, including ulcerative colitis that has an increased incidence for colorectal carcinoma (CAC). The aim of this study was to determine the expression of TJ proteins, claudin-1-4, occludin, ZO-1, and the adherens junction (AJ) protein beta-catenin in CAC.

METHODS

Sixteen colectomy specimens with CAC, adjoining intraepithelial neoplasia, and normal mucosa were studied by immunofluorescence. A semiquantitative evaluation of all investigated proteins was performed by scoring the staining intensity, and the TJ and AJ protein expression in neoplastic cells was compared to normal and intraepithelial neoplastic colonic mucosa.

RESULTS

Using an intensity scoring system, mucosa of crypts and surfaces of CAC exhibited significantly elevated expression levels of claudin-1, claudin-3, claudin-4, and beta-catenin compared to intraepithelial neoplasia and normal mucosa (p<0.05). These data were confirmed by a comparative score. The expression of claudin-2, occludin, and ZO-1 showed no differences between the groups.

CONCLUSION

TJ proteins claudin-1, claudin-3, claudin-4, and the AJ protein beta-catenin are overexpressed in CAC. This suggests that these proteins may become potential markers and targets in CAC.

CD4+ T cells transfer resistance against Citrobacter rodentium-induced infectious colitis by induction of Th 1 immunity

Citrobacter rodentium induces an acute, self-limited colitis in mice which is histologically associated with crypt hyperplasia. The infection serves as a model for human infectious colitis induced by enteropathogenic Escherichia coli. We investigated if Balb/c mice, which had spontaneously cleared C. rodentium infection, were protected against re-infection and if resistance against intestinal infection can be systemically transferred using spleen cells. The course of infection was monitored by faecal excretion. Spleen cells, splenic CD3+ and CD4+ cells were transferred from resistant mice to non-infected recipients prior to infection. Cytokine secretion, serum and faecal antibody titres and histological disease severity were assessed. Balb/c mice were resistant against re-infection. The course of infection was shorter in mice receiving primed spleen cells, CD3+ and CD4+ cells. Transfer of CD4+ T cells from resistant mice induced gamma-interferon, interleukin (IL)-2 and IL-17 secretion and suppressed IL-10 secretion. Anti-Citrobacter serum IgG1 and IgG2a enzyme-linked immunosorbent assay OD levels were increased. Faecal IgA secretion was increased while serum IgA was suppressed in recipients of CD4+ cells. Large bowel histology showed protection from colitis in recipients of primed cells as indicated by normal colonic epithelium. In Balb/c mice, C. rodentium infection is followed by resistance, which can be transferred by CD4+ cells. Transfer of protection is associated with IL-17 secretion, enhanced serum IgG and faecal IgA secretion. This is the first study to demonstrate the mechanisms by which systemic resistance from previously C. rodentium-infected mice can be transferred to non-infected animals.

Heart Transplantation for Isolated Noncompaction of the Left Ventricle in an Infant

Isolated noncompaction of the left ventricular myocardium is a rare cardiomyopathy typically showing a "spongy" myocardium on ultrasound. We report on the ultrasonic and pathomorphological characteristics of an infant who, at the age of 40 days, was treated by heart transplantation for isolated noncompaction. Noncompaction should be suspected in newborns with otherwise unexplained cardiomyopathy and a "spongy" left ventricle. However, ultrasonic and pathological findings may be much less pronounced at this age than later in life.

Neoplastic Heart Disease - The Muenster Experience With 108 Patients

BACKGROUND

Tumours of the heart are rare. Different histological subtypes are known. The most common tumour entity is benign cardiac myxoma. Malignant heart tumours are less common. Tumours originating in other organs such as the kidney may also affect the heart by tumour progression via the inferior caval vein. A large experience with surgical treatment of different types of heart tumours is presented.

METHODS

Between January 1989 and April 2004, 108 patients with a heart tumour were included in a database. All patients underwent radical surgical resection, except for 2 patients who had malignant lymphoma of the heart.

RESULTS

Histological findings included 78 myxomas (72.2 %), and 6 other benign cardiac tumours in 5.6 % of the patients. Primary malignant heart tumours were seen in 10 (9.2 %) and renal cell carcinoma with cardiac involvement in 6 (5.6 %) patients. Eight patients presented with tumour metastases inside the heart (7.4 %). Mean overall survival was 12.7 years for myxoma patients and 5.6 years for patients with other benign heart tumours. Patients with primary malignant heart tumours survived 5.5 years on average.

CONCLUSIONS

Heart tumours are rare, but usually life-threatening. Radical surgical resection is the therapy of choice and may offer excellent long-term survival, even in cases with malignant heart tumours.

Survival and clonal expansion of mutating "forbidden" (immunoglobulin receptor-deficient) epstein-barr virus-infected b cells in angioimmunoblastic t cell lymphoma

Angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) is a peculiar T cell lymphoma, as expanding B cell clones are often present besides the malignant T cell clones. In addition, large numbers of Epstein-Barr virus (EBV)-infected B cells are frequently observed. To analyze the differentiation status and clonal composition of EBV-harboring B cells in AILD, single EBV-infected cells were micromanipulated from lymph nodes of six patients with frequent EBV(+) cells and their rearranged immunoglobulin (Ig) genes analyzed. Most EBV-infected B cells carried mutated Ig genes, indicating that in AILD, EBV preferentially resides in memory and/or germinal center B cells. EBV(+) B cell clones observed in all six cases ranged from small polyclonal to large monoclonal expansions and often showed ongoing somatic hypermutation while EBV(-) B cells showed little tendency for clonal expansion. Surprisingly, many members of expanding B cell clones had acquired destructive mutations in originally functional V gene rearrangements and showed an unfavorable high load of replacement mutations in the framework regions, indicating that they accumulated mutations over repeated rounds of mutation and division while not being selected through their antigen receptor. This sustained selection-free accumulation of somatic mutations is unique to AILD. Moreover, the survival and clonal expansion of "forbidden" (i.e., Ig-deficient) B cells has not been observed before in vivo and thus represents a novel type of viral latency in the B cell compartment. It is likely the interplay between the microenvironment in AILD lymph nodes and the viral transformation that leads to the survival and clonal expansion of Ig-less B cells.

Low prevalence of latently Epstein-Barr virus-infected cells in chronic gastritis

The association of Epstein-Barr virus (EBV) with a proportion of gastric carcinomas is well established. The role of EBV in conditions predisposing to carcinoma such as chronic gastritis has remained undefined, however. We used in situ hybridization with radioactive and nonradioactive single-stranded RNA probes specific for the EBV small latent nuclear transcripts, EBER1 and EBER2, to analyze biopsy specimens from 242 patients with mild to severe chronic gastritis of Sydney classification types A, B, and C. A small number of EBV infected lymphocytes was detected in only nine cases, even in biopsies investigated with radioactive probes. Labeling of epithelial or stromal cells was not observed. The paucity of latently EBV-infected cells in chronic gastritis biopsies differs from the previously reported higher prevalence of virus carrying cells in inflammatory conditions at other sites of the gastrointestinal tract. These findings argue against a direct involvement of EBV in the pathogenesis of chronic gastritis. The low prevalence of EBV-positive cells suggests that local factors do not favor the entry and retention of circulating EBV-infected lymphocytes in gastric mucosa. Moreover, our findings indicate that EBV infection of gastric epithelial cells is not an early event in gastric carcinogenesis.

Molecular single-cell analysis of Hodgkin- and Reed-Sternberg cells harboring unmutated immunoglobulin variable region genes

Hodgkin- and Reed-Sternberg (H/RS) cells in classical Hodgkin's disease of the B lineage are the clonal progeny of antigen-experienced B cells harboring highly mutated immunoglobulin variable (V) region genes. Based on the detection of obviously destructive somatic mutations in a fraction of cases, we speculated that H/RS cells may be derived from a pre-apoptotic germinal center B cell. Seemingly contradicting this speculation, we present here the first case of classical Hodgkin's disease with H/RS cells harboring unmutated, potentially functional V region genes, which may indicate the derivation of the H/RS clone from a naive B cell. However, germinal center founder cells, which have not yet acquired somatic mutations, already have the intrinsic propensity to die by apoptosis. Thus, the rare occurrence of H/RS cells with unmutated V genes is expected if the H/RS cells are derived from the pool of pre-apoptotic germinal center B cells.

Molecular single-cell analysis of the clonal relationship of small Epstein-Barr virus-infected cells and Epstein-Barr virus-harboring Hodgkin and Reed/Sternberg cells in Hodgkin disease

Epstein-Barr virus (EBV) can be detected in the tumor cells of approximately 40% of cases of classical Hodgkin disease (cHD). Clonality studies suggest that infection of the neoplastic Hodgkin and Reed/Sternberg (HRS) cells occurs before tumor clone expansion. In EBV-positive cases, variable numbers of EBER-positive small B cells are sometimes also observed that immunohistologically differ from the neoplastic cells by lack of CD30 and latent membrane protein 1 expression. To analyze the clonal relationship between these EBV(+) cells and the HRS cells, single EBV-infected CD30(-) B cells, as well as HRS cells from 3 cases of EBV-positive cHD were micromanipulated, their immunoglobulin gene rearrangements amplified and then compared with each other. In 2 cases, all small EBV-infected cells were clonally unrelated to the HRS cells. In a third case, 2 of 29 small CD30(-) cells were found to carry HRS cell-specific rearrangements. Thus, small CD30(-) EBV-infected B cells in cHD belong to the HRS tumor clone rarely, if at all. In all cases, small clones unrelated to the HRS cell clones were identified among the small EBV(+) CD30(-) cells. The vast majority of small EBV(+) CD30(-) B cells was found to carry somatically mutated V region genes, indicating that in lymph nodes of patients with HD, like in the peripheral blood of healthy individuals, EBV persists in memory B cells.

EBV-infected B cells in infectious mononucleosis: viral strategies for spreading in the B cell compartment and establishing latency

Infection of humans with Epstein-Barr virus (EBV) may cause infectious mononucleosis (IM). Analysis of single EBV-infected cells from tonsils of IM patients for rearranged immunoglobulin genes revealed two strategies of EBV for rapid and massive spread in the B cell compartment: the direct infection of many naive as well as memory and/or germinal center B cells and the expansion of the latter cells to large clones. In IM, the generation of virus-harboring memory B cells from naive B cells passing through a germinal center reaction likely plays no role. Members of clones can show distinct morphologies and likely also EBV gene expression patterns, and this ability implies a mechanism by which EBV-harboring cells can evade immune surveillance and establish a pool of persisting EBV-infected B cells.

Distribution and phenotype of Epstein-Barr virus-infected cells in inflammatory bowel disease

Little is known about Epstein-Barr virus (EBV) infection of colon mucosa, particularly in inflammatory bowel diseases. Crohn's disease and ulcerative colitis are thought to differ in T-helper lymphocyte composition and cytokine secretion patterns. Some of the implicated cytokines are growth factors for EBV-infected cells. We examined colon mucosa for differences in the distribution and phenotype of EBV-infected cells. Colon tissues with Crohn's disease (n = 31) or ulcerative colitis (n = 25) and controls (n = 60) were characterized by in situ hybridization and immunohistology for six EBV gene products as indicators of latent and replicative EBV infection. The cells were additionally phenotyped by combined detection of the EBV transcripts and B- or T-cell antigens. B lymphocytes predominated as the site of latent EBV infection in the colon and were most numerous in ulcerative colitis. In active ulcerative colitis, EBV-positive lymphocytes accumulated under and within the epithelium and displayed evidence for replicative infection. The patterns of mucosal EBV gene expression indicate local impairment of virus-specific T-cell responses in active ulcerative colitis. Detection of EBV may help to discriminate between active ulcerative colitis and other inflammatory bowel diseases. Colon mucosa is a potential site of EBV replication and may be relevant for EBV transmission.

Molecular analysis of single B cells from T-cell-rich B-cell lymphoma shows the derivation of the tumor cells from mutating germinal center B cells and exemplifies means by which immunoglobulin genes are modified in germinal center B cells

T-cell-rich B-cell lymphoma (TCRBCL) belongs to the group of diffuse large cell lymphomas (DLL). It is characterized by a small number of tumor B cells among a major population of nonmalignant polyclonal T cells. To identify the developmental stage of the tumor progenitor cells, we micromanipulated the putative neoplastic large CD20(+) cells from TCRBCLs and amplified and sequenced immunoglobulin (Ig) V gene rearrangements from individual cells. In six cases, clonal Ig heavy, as well as light chain, gene rearrangements were amplified from the isolated B cells. All six cases harbored somatically mutated V gene rearrangements with an average mutation frequency of 15.5% for heavy (VH) and 5.9% for light (VL) chains and intraclonal diversity based on somatic mutation. These findings identify germinal center (GC) B cells as the precursors of the transformed B cells in TCRBCL. The study also exemplifies various means how Ig gene rearrangements can be modified by GC B cells or their malignant counterparts in TCRBCL: In one case, the tumor precursor may have switched from kappa to lambda light chain expression after acquiring a crippling mutation within the initially functional kappa light chain gene. In another case, the tumor cells harbor two in-frame VH gene rearrangements, one of which was rendered nonfunctional by somatic mutation. Either the tumor cell precursor entered the GC with two potentially functional in-frame rearrangements or the second VHDHJH rearrangement occurred in the GC after the initial in-frame rearrangement was inactivated by somatic mutation. Finally, in each of the six cases, at least one cell contained two (or more) copies of a clonal Ig gene rearrangement with sequence variations between these copies. The presence of sequence variants for V region genes within single B cells has so far not been observed in any other normal or transformed B lymphocyte. Fluorescence in situ hybridization (FISH) points to a generalized polyploidy of the tumor cells.

Generalised acanthosis nigricans with vitiligo

We report on a 19-year-old woman with generalised acanthosis nigricans of the inherited type and concomitant vitiligo. Cutaneous velvety thickening of the skin with intensification of skin markings and progressive development of hyperpigmented papillomatous, verrucoid lesions in the body folds started to develop in early childhood. These hyperpigmentations were continuously replaced by a progressive vitiligo, finally leaving most of the acanthosis nigricans lesions completely depigmented. Generalised, pachyderma-like acanthosis nigricans with concomitant vitiligo is an association which to the best of our knowledge has not yet been described.