Abstract P2-08-47: Evaluation of stromal tumor-infiltrating lymphocytes (sTIL) and tertiary lymphoid structures (TLS) in early breast cancer patients with triple negative breast cancer(TNBC) included in a prospective study of neoadjuvant chemotherapy (NAC) with Epirubicin and cyclophosphamide (EC) and carboplatin-paclitaxel (PC) (BSMO 2014-01)

Background: BSMO 2014-01 is a completed prospective phase 2 study evaluating the efficacy of neoadjuvant EC and PC. One of the secondary endpoints was the correlation of sTIL with response, pCR and survival. We also assessed the relationship between sTIL and TLS in the diagnostic biopsies.

Methods: Stromal TIL (sTIL) were evaluated on H&E stained tumor biopsies before the start of the NAC according to the criteria described by Salgado et al(1). Scores were defined as "low" or "high" if lymphocytic infiltration in the stroma around the tumor was ≤ 10% or > 10%. TLS are ectopic lymph node-like structures recently identified in breast cancer. TLS were counted using a dual IHC stain for CD3 (T cells) and CD20 (B cells) and categorized as "little" if the TLS occupied < 10% or "moderate to abundant" if they occupied ≥ 10% of the adjacent tissue. The correlation between sTIL and pathologic parameters was analyzed using the chi-square test; DFS and OS between the groups was estimated by using the log-rank test.

Results: So far we could quantify the number of sTIL in 38 out of 63 TNBC pts treated with neoadjuvant EC-PC. Twenty eight pts had a high sTIL score and 10 pts had a low sTIL score. The high-sTIL group (19/28) achieved a numerical higher pathologic complete remission (pCR) rate than the low-sTIL group (5/10) (p=0.3); both groups had a comparable disease free survival of 28.6 mths and 26.7 mths respectively (p=0.7). The overall survival was similar:29 mths and 27.8 mths respectively (p=0.8). Stromal TLS were identified in 10 out 23 samples available for this analysis and we could demonstrate a positive correlation between high levels of sTIL and high levels of moderate to abundant TLS(CD3) in the adjacent tissue in six out of the ten samples in which TLS were present (p=0.1).

Conclusion: These preliminary results could not confirm the results published by Denkert et al earlier this year(2). A trend for correlation of the presence of high sTIL with moderate to abundant levels of TLS was found. Analysis on the remaining samples of all patients included in the study and correlation with outcome is ongoing and these completed results will be presented.

(1)Assessing Tumor-infiltrating lymphocytes in solid tumors. Hendry S, Salgado R et al. Adv Anat Pathol 2017; 235-251.

(2)Tumour-infiltrating lymphocytes and prognosis in different subtypes of breast cancer. Denkert C et al. Lancet Oncol 2018; 40-50.

Citation Format: Fontaine C, Van den Eynden G, de Wind R, Boisson A, Renard V, Van den Bulck H, Vuylsteke P, Glorieux P, Dopchie C, Decoster L, De Grève J, Awada A, Wildiers H, Willard-Gallo K. Evaluation of stromal tumor-infiltrating lymphocytes (sTIL) and tertiary lymphoid structures (TLS) in early breast cancer patients with triple negative breast cancer(TNBC) included in a prospective study of neoadjuvant chemotherapy (NAC) with Epirubicin and cyclophosphamide (EC) and carboplatin-paclitaxel (PC) (BSMO 2014-01) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-08-47.

Abstract P5-16-06: Neoadjuvant weekly carboplatin and paclitaxel followed by dose dense epirubicin and cyclophosphamide in triple negative breast cancer patients: A single arm phase II study from the Belgian Society of Medical Oncology

Introduction: Triple negative breast cancer (TNBC) remains a challenging disease with dismal prognosis. Platinum analogs have not yet shown to improve long term outcome in this setting, but are associated with increased pathological complete response rate (pCR) at the cost of higher toxicity.

Aim: To further increase or maintain the high pCR rate with platinum containing schedules while decreasing toxicity by administering low dose weekly carboplatin instead of high-dose 3 weekly carboplatin as in CALGB 40603.(1)

Patients and methods: We evaluated the tolerability and the impact of the addition of weekly carboplatin (CP) to paclitaxel (P) and dose dense epirubicin-cyclofosfamide (EC) on pCR in an open-label multicenter phase II study in stage II/III TNBC patients (pts). Sixty three pts received dose dense paclitaxel (P:80mg/m2/wk) concurrent with carboplatin (CP: AUC=2) for 12 wks, followed by two-weekly epirubicin (E:90mg/m2) and cyclophosphamide (C:600mg/m2) for 4 cycles. The primary endpoint is pCR in the breast and axilla. Additionally treatment deliveryand adverse events are recorded. A correlative assessment of germline mutations in homologous recombination (HR) genes is planned. Pts are monitored for response by magnetic resonance and mammography and also for relapse free survival and time to treatment failure. The study size sample has been calculated according to the optimal Simon's two-stage design method. The target sample size was 63 patients with 80% power to detect a pCR rate of ≥47% (α= 0.05).

Results: Accrual to the study is completed with 63 eligible pts with operable, noninflammatory stage II and III TNBC included. Most patients were between 40 and 60 yrs old and were clinical stageT2 tumors. Half of the pts were clinically node + and 70% were G3. Sixty six percent had breast conserving surgery. Sixteen out of 26 (61.5%) of the currently evaluable pts achieved a pCR rate in the breast and axilla. The other ongoing patients have not yet reached this endpoint. Four out of 21 evaluable pts that completed the chemotherapy missed two or more doses of CP due to neutropenia(NP) G3/4(2), general deterioration G3(1) and polyneuropathy(PNP) G3(1) and seven pts needed one dose reduction of P and/or CP due to NP G3-4 (3-2) and PNP G2(1) and one abdominal infection.

Conclusion: These preliminary data suggest that the addition of weekly carboplatinum to neoadjuvant paclitaxel and EC is feasible and has a promising pCR rate in the breast and axilla as high as 61.5% in early TNBC pts. More mature toxicity and outcome data and correlation with genome analysis will be presented.

(1) Impact of the addition of carboplatin and/or bevacizumab to neoadjuvant once per week paclitaxel followed by dose-dense doxorubicin and cyclophosphamide on pathologic complete response rates in stage II to III triple-negative breast cancer: CALGB 40603(Alliance) Sikov WM et al. J Clin Oncol 33:13-21; 2014.

Citation Format: Fontaine C, Cappoen N, Renard V, Vuylsteke P, Van Den Bulck H, Glorieux P, t'Kint de Roodenbeke D, Dopchie C, Decoster L, Vanacker L, De Grève J, Awada A, Wildiers H. Neoadjuvant weekly carboplatin and paclitaxel followed by dose dense epirubicin and cyclophosphamide in triple negative breast cancer patients: A single arm phase II study from the Belgian Society of Medical Oncology [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-16-06.

Effects 4.5 years after an interactive GP educational seminar on antibiotic therapy for respiratory tract infections: a randomized controlled trial

BACKGROUND

The few studies assessing long-term effects of educational interventions on antibiotic prescription have produced conflicting results.

OBJECTIVES

Our aim was to assess the effects after 4.5 years of an interactive educational seminar designed for GPs and focused on antibiotic therapy in respiratory tract infections (RTIs). The seminar was expected to decrease antibiotic prescriptions for any diagnosis.

METHODS

We conducted a randomized controlled parallel-group trial in a Paris suburb (France), with GPs as the randomization unit and prescriptions as the analysis unit. The intervention occurred in September 2004 and the final assessment in March 2009. Among 203 randomized GPs, 168 completed the study, 70 in the intervention group and 98 in the control group. Intervention GPs were randomized to attending only a 2-day interactive educational seminar on evidence-based guidelines about managing RTIs or also 1 day of problem-solving training. The primary outcome was the percentage of change in the proportion of prescriptions containing an antibiotic for any diagnosis in 2009 versus 2004. An intention-to-treat sensitivity analysis was performed using multiple imputation.

RESULTS

After 4.5 years, absolute changes in the primary outcome measure were -1.1% (95% confidence interval: -2.2 to 0.0) in the intervention group and +1.4% (0.3-2.6) in the control group, yielding an adjusted between-group difference of -2.2% (-2.7 to -1.7; P < 0.001). Both intervention modalities had significant effects, and multiple imputation produced similar results.

CONCLUSIONS

A single, standardized and interactive educational seminar targeting GPs significantly decreased antibiotic use for RTIs after 4.5 years.

Neoadjuvant capecitabine and docetaxel (plus trastuzumab): an effective non-anthracycline-based chemotherapy regimen for patients with locally advanced breast cancer

BACKGROUND

To evaluate capecitabine-docetaxel (XT), with trastuzumab (H) in human epidermal growth factor receptor 2 (HER2)-positive disease, in inoperable locally advanced breast cancer (LABC).

PATIENTS AND METHODS

Patients received up to six neoadjuvant 21-day cycles of capecitabine 900 mg/m(2) twice daily, days 1-14, plus docetaxel 36 mg/m(2), days 1 and 8. Patients with HER2-positive disease also received trastuzumab 6 mg/kg every 3 weeks. The primary end point was pathologic complete response (pCR) rate, evaluated separately in HER2-negative and HER2-positive cohorts. Secondary end points included clinical response rates and tolerability.

RESULTS

The pCR rate was 15% [95% confidence interval (CI) 7-28] in 53 patients receiving XT and 40% (95% CI 26-55) in 50 patients receiving HXT. After neoadjuvant therapy, 50 patients receiving XT and 45 receiving HXT underwent surgery. No unexpected toxicity was observed: the most common grade ≥3 adverse events were diarrhea/mucositis (30% and 20%, respectively) and grade 3 hand-foot syndrome (11% and 6%, respectively). Disease-free survival and overall survival were similar with XT and HXT after median follow-up of 22 months in the XT cohort and 21 months in the HXT cohort.

CONCLUSION

Neoadjuvant XT (HXT in HER2-positive disease) is highly effective in inoperable LABC, demonstrating pCR rates of 15% and 40%, respectively. This non-anthracycline-containing regimen offers obvious benefits in early disease, where avoidance of long-term cardiotoxicity is particularly important.

Neurological grading, survival, MR imaging, and histological evaluation in the rat brainstem glioma model

OBJECTIVE

Convection-enhanced delivery using carboplatin in brainstem glioma models was reported to prolong survival. Functional impairment is of additional importance to evaluate the value of local chemotherapy. We established a neurological scoring system for the rat brainstem glioma model.

MATERIAL AND METHODS

In 46 male Fisher rats stereotactically 10(5) F-98 cells were implanted at 1.4-mm lateral to midline and at the lambdoid suture using guided screws. Following 4 days local delivery was performed using Alzet pumps (1 microl/h over 7 days) with either vehicle (5% dextrose) or carboplatin via one or two cannulas, respectively. All rats were subsequently tested neurologically using a specified neurological score. In 38 animals survival time was recorded. Representative MR imaging were acquired in eight rats, respectively, at day 12 after implantation. HE staining was used to evaluate tumor extension.

RESULTS

Neurological scoring showed significantly higher impairment in the high dose carboplatin group during the treatment period. Survival was significantly prolonged compared to control animals in the high dose carboplatin-one cannula group as well as in both low dose carboplatin groups (18.6 +/- 3 versus 26.3 +/- 9, 22.8 +/- 2, 23.6 +/- 2 days; p < 0.05). Overall neurological grading correlated with survival time. MR imaging showed a focal contrast enhancing mass in the pontine brainstem, which was less exaggerated after local chemotherapy. Histological slices visualized decreased cellular density in treatment animals versus controls.

CONCLUSION

Local chemotherapy in the brainstem glioma model showed significant efficacy for histological changes and survival. Our neurological grading enables quantification of drug and tumor-related morbidity as an important factor for functional performance during therapy.

Iodine-123-interleukin-2 scintigraphy in metastatic hypernephroma: a pilot study

AIM

This pilot study reports on the uptake of (123)I-interleukin 2 (IL-2) in metastatic renal cell carcinoma (MRCC) patients and its relationship to prognostic factors of response or failure of MRCC to cytokines treatment.

METHODS

Nine consecutive patients with MRCC underwent an (123)I-IL-2 scan (6 male and 3 female; mean age 64 years; range 51-78). Uptake in metastases was related to a summed score of 4 independent factors, predictive of rapid progression under cytokine treatment as defined by Negrier et al.

RESULTS

Four patients presented with metastases at one site, 4 at 2 sites and one patient at 3 different sites. Summed scores were: 5 patients had a summed score of 1; 3 a summed score of 2 and 1 patient a summed score of 3. Uptake of (123)I-IL-2 by tumor tissue was found in only 2 patients. Uptake occurred in 1 patient with a summed score of 3 and in 1 with a summed score of 2.

CONCLUSION

In this small series of patients with MRCC, (123)I-IL-2 uptake was found in tumors of 2 patients who less likely will benefit from cytokine treatment. Additional studies are needed to assess the relationship between the pretreatment uptake of (123)/I-IL2 in MRCC and the response to IL-2 therapy.

Perspectives on the development of a therapeutic HER-2 cancer vaccine

With good reason, the majority of cancer vaccines tested, or being tested, have targeted the induction of anti-tumour CTL responses. However, the clinical success of monoclonal antibodies such as Rituximab/CD20, Trastuzumab/HER-2, Cetuximab/EGFR and Bevacisumab/VEGF suggests that their respective targets may also be relevant for cancer vaccines aiming at the induction of an effective humoral anti-tumour response to mimic, or potentially improve upon, the effects of monoclonal therapies. We report here an overview of the development of a protein vaccine targeting HER-2/neu, with an emphasis on the immunologic results obtained from the testing of the vaccine in animal models of disease and in toxicology programs, to its evaluation in three clinical trials in breast cancer patients.

A Belgian registry of interleukin-2 administration for treatment of metastatic renal cell cancer and confrontation with literature data

In an effort to map the use of interleukin-2 (IL-2) treatment in patients with clear cell renal cell cancer (RCC) in Belgian hospitals, 44 cases were registered from 9 hospitals between February 2003 and June 2006. It was demonstrated that the majority of these patients were treated with subcutaneous (SC) IL-2. Other methods such as the inhalation of the drug in case of intrathoracic disease or high dose intravenous (IV) administration were much less frequent (3 and 0 cases in this registry, respectively). The results of antitumour activity (around 16% partial response-absence of complete responses) and toxicity of this drug correlate with observations from the literature with the SC administration. In view of the poor results and tolerance with the currently used cytokines (IL-2 or interferon-alfa), much hope is directed towards the development of the novel targeted drugs like sunitinib or sorafenib used alone or in combination with cytokines in this disease.

Femtosecond time resolved coherent anti-Stokes Raman spectroscopy: experiment and modelization of speed memory effects on H2-N2 mixtures in the collision regime

With the aim of temperature diagnostic, femtosecond time-resolved CARS (coherent anti-Stokes Raman spectroscopy) is applied to probe H2 in H2-N2 mixtures. In a first part, a Lorentzian profile is used to model the femtosecond CARS response. A difference between the experimental broadening and the expected one is observed in the collision regime. The observed broadening increases strongly in an inhomogeneous way with respect to the perturber concentration. This is of considerable importance for temperature measurements. In a second part, we show that in the collision regime, this inhomogeneous broadening is due to the speed dependence of the collisional parameters and the memory effects of the radiator speed. A new modelization of the time-resolved CARS response taking into account the speed memory effects is presented and applied to the temperature diagnostic in H2-N2 mixtures. The numerical results are in good agreement with experiments.

HER-2 DNA and protein vaccines containing potent Th cell epitopes induce distinct protective and therapeutic antitumor responses in HER-2 transgenic mice

Overexpression of the growth factor receptor HER-2 (c-erbB-2, neu) has transforming potential and occurs in approximately 20-30% of breast and ovarian cancers. HER-2 is a self Ag, but Abs and T cells specific for HER-2 have been isolated from cancer patients, suggesting HER-2 may be a good target for active immunotherapy. We constructed rat HER-2 DNA and protein vaccines containing potent Th cell epitopes derived from tetanus toxin and studied their potency in two strains of mice transgenic for the rat HER-2 molecule. Vaccination with HER-2 DNA protected nontransgenic mice from tumor challenge, but induced only moderate protection in one of the tumor models. However, vaccination with the modified HER-2 protein resulted in almost complete protection from tumor challenge in both tumor models. This protection could be mediated by Abs alone. In addition, protein vaccination efficiently eliminated pre-established tumors in both models, even when vaccination occurred 9 days after tumor implantation. These data demonstrate the potential of HER-2-based vaccines as therapeutic agents for the treatment of cancers overexpressing HER-2.

Postpulse molecular alignment measured by a weak field polarization technique

We report a direct nonintrusive observation of alignment and planar delocalization of CO2 after an intense linearly polarized femtosecond laser pulse excitation. The effects are measured by a polarization technique involving a perturbative probe that itself does not induce appreciable alignment. We show that this technique allows one to measure a signal proportional to <cos((2)theta>-1/3, with theta the angle between the molecular axis and the laser polarization. Simulations that support this analysis allow one to characterize the experimentally observed alignment and planar delocalization quantitatively.

Inhibition of natural killer cell activation signals by killer cell immunoglobulin-like receptors (CD158)

The killer cell immunoglobulin-like receptor (KIR) family includes receptors that bind to HLA class I molecules on target cells and inhibit natural killer (NK)-cell cytotoxicity, and receptors such as KIR3DL7 with no known ligand and function. Inhibitory KIR recruit the tyrosine phosphatase SHP-1 to block signals transduced by any one of a number of activation receptors. Inhibition of overall protein tyrosine phosphorylation by SHP-1 during binding of KIR to MHC class I on target cells is selective, suggesting that a limited number of substrates are dephosphorylated by SHP-1. We have chosen to study KIR inhibition as it occurs during binding of KIR to MHC class I on target cells, despite the technical limitations inherent to studies of processes regulated by cell contact. KIR binding to MHC class I on target cells inhibits tyrosine phosphorylation of the activation receptor 2B4 (CD244) and disrupts adhesion of NK cells to target cells. Inhibition of proximal events in NK activation may increase the availability of NK cells by liberating them from non-productive interactions with resistant target cells. As the receptors and the signaling pathways that induce NK cytotoxicity are not fully characterized, elucidation of the inhibitory mechanism employed by KIR may provide insight into NK activation.

Transduction of cytotoxic signals in natural killer cells: a general model of fine tuning between activatory and inhibitory pathways in lymphocytes

NK-cells are large granular lymphocytes, which are capable of exerting two major types of effector function, cell cytotoxicity and lymphokine secretion. NK-cells can exert cell cytotoxicity in one of two ways. First, NK-cells are able to recognize and to induce the lysis of antibody-coated target cells during antibody-dependent cell cytotoxicity (ADCC). Second, during natural cytotoxicity NK-cells are also able to recognize and to induce the lysis of a variety of target cells, including primarily virus-infected cells as well as tumor cells. Recently, a novel mechanism has been elucidated which controls NK-cell-activation programs and which is based on the cell surface expression of killer-cell inhibitory receptors (KIR). We will review here the molecular dissection of this inhibitory signalling pathway which utilizes immunoreceptor tyrosine-based inhibition motifs (ITIM) expressed in KIR intracytoplasmic domain. We will also show that this strategy used by NK-cells to regulate their effector functions is a general decision mechanism which exists not only in T- and B-lymphocytes, but also in a variety of other hematopoietic cells.

The CD8 beta polypeptide is required for the recognition of an altered peptide ligand as an agonist

T cell activation is triggered by the specific recognition of cognate peptides presented by MHC molecules. Altered peptide ligands are analogs of cognate peptides which have a high affinity for MHC molecules. Some of them induce complete T cell responses, i.e. they act as agonists, whereas others behave as partial agonists or even as antagonists. Here, we analyzed both early (intracellular Ca2+ mobilization), and late (interleukin-2 production) signal transduction events induced by a cognate peptide or a corresponding altered peptide ligand using T cell hybridomas expressing or not the CD8 alpha and beta chains. With a video imaging system, we showed that the intracellular Ca2+ response to an altered peptide ligand induces the appearance of a characteristic sustained intracellular Ca2+ concentration gradient which can be detected shortly after T cell interaction with antigen-presenting cells. We also provide evidence that the same altered peptide ligand can be seen either as an agonist or a partial agonist, depending on the presence of CD8beta in the CD8 co-receptor dimers expressed at the T cell surface.

CD8 beta increases CD8 coreceptor function and participation in TCR-ligand binding

To study the role of CD8 beta in T cell function, we derived a CD8 alpha/beta-(CD8-/-) T cell hybridoma of the H-2Kd-restricted N9 cytotoxic T lymphocyte clone specific for a photoreactive derivative of the Plasmodium berghei circumsporozoite peptide PbCS 252-260. This hybridoma was transfected either with CD8 alpha alone or together with CD8 beta. All three hybridomas released interleukin 2 upon incubation with L cells expressing Kd-peptide derivative complexes, though CD8 alpha/beta cells did so more efficiently than CD8 alpha/alpha and especially CD8-/- cells. More strikingly, only CD8 alpha/beta cells were able to recognize a weak agonist peptide derivative variant. This recognition was abolished by Fab' fragments of the anti-Kd alpha 3 monoclonal antibody SF1-1.1.1 or substitution of Kd D-227 with K, both conditions known to impair CD8 coreceptor function. T cell receptor (TCR) photoaffinity labeling indicated that TCR-ligand binding on CD8 alpha/beta cells was approximately 5- and 20-fold more avid than on CD8 alpha/a and CD8-/- cells, respectively. SF1-1.1.1 Fab' or Kd mutation D227K reduced the TCR photoaffinity labeling on CD8 alpha/beta cells to approximately the same low levels observed on CD8-/- cells. These results indicate that CD8 alpha/beta is a more efficient coreceptor than CD8alpha/alpha, because it more avidly strengthens TCR-ligand binding.

Desulfitobacterium sp. strain PCE1, an anaerobic bacterium that can grow by reductive dechlorination of tetrachloroethene or ortho-chlorinated phenols

A strictly anaerobic bacterium, strain PCE1, was isolated from a tetrachloroethene-dechlorinating enrichment culture. Cells of the bacterium were motile curved rods, with approximately four lateral flagella. They possessed a gram-positive type of cell wall and contained cytochrome c. Optimum growth occurred at pH 7.2-7.8 and 34-38 degrees C. The organism grew with L-lactate, pyruvate, butyrate, formate, succinate, or ethanol as electron donors, using either tetrachloroethene, 2-chlorophenol, 2,4,6-trichlorophenol, 3-chloro-4-hydroxy-phenylacetate, sulfite, thiosulfate, or fumarate as electron acceptors. Strain PCE1 also grew fermentatively with pyruvate as the sole substrate. L-Lactate and pyruvate were oxidized to acetate. Tetrachloroethene was reductively dechlorinated to trichloroethene and small amounts ( 5%) of cis-1,2-dichloroethene and trans-1,2-dichloroethene. Chlorinated phenolic compounds were dechlorinated specifically at the ortho-position. On the basis of 16S rRNA sequence analysis, the organism was identified as a species within the genus Desulfitobacterium, which until now only contained the chlorophenol-dechlorinating bacterium, Desulfitobacterium dehalogenans.

Complete degradation of tetrachloroethene by combining anaerobic dechlorinating and aerobic methanotrophic enrichment cultures

Degradation of tetrachloroethene (perchloroethylene, PCE) was investigated by combining the metabolic abilities of anaerobic bacteria, capable of reductive dechlorination of PCE, with those of aerobic methanotrophic bacteria, capable of co-metabolic degradation of the less-chlorinated ethenes formed by reductive dechlorination of PCE. Anaerobic communities reductively dechlorinating PCE, trichloroethene (TCE) and dichloroethenes were enriched from various sources. The maximum rates of dechlorination observed for various chloroethenes in these batch enrichments were: PCE to TCE (341 mumol l-1 day-1), TCE to cis-dichloroethene (159 mumol l-1 day-1), cis-dichloroethene to chloroethene (99 mumol l-1 day-1) and trans-dichloroethene to chloroethene (22 mumol l-1 day-1). A mixture of these enrichments was inoculated into an anoxic fixed-bed upflow column. In this column PCE was converted mainly into cis-1,2-dichloroethene, small amounts of TCE and chloroethene, and chloride. Enrichments of aerobic methanotrophic bacteria were grown in an oxic fixed-bed downflow column. Less-chlorinated ethenes, formed in the anoxic column, were further metabolized in this oxic methanotrophic column. On the basis of analysis of chloride production and the disappearance of chlorinated ethenes it was demonstrated that complete degradation of PCE was possible by combining these two columns. Operation of the two-column system under various process conditions indicated that the sensitivity of the methanotrophic bacteria to chlorinated intermediates represented the bottle-neck in the sequential anoxic/oxic degradation process of PCE.

Normal development and function of natural killer cells in CD3 epsilon delta 5/delta 5 mutant mice

The CD3 epsilon polypeptide contributes to the cell surface display as well as to the signal transduction properties of the T-cell antigen receptor complex. Intriguingly, the distribution of CD3 epsilon is not restricted to T cells, since activated mouse, human, and avian natural killer (NK) cells do express intracytoplasmic CD3 epsilon polypeptides. CD3 epsilon is also present in the cytoplasm of fetal thymic T/NK bipotential progenitor cells, suggesting that it constitutes a component of the NK differentiation program. We report here that the genetic disruption of CD3 epsilon exon 5 alters neither NK cell development nor in vitro and in vivo NK functions, although it profoundly blocked T-cell development. These results support the notion that CD3 epsilon is dispensable for mouse NK cell ontogeny and function and further suggest that the common NK/T-cell progenitor cell utilizes CD3 epsilon as a mandatory component only when differentiating toward the T-cell lineage.

Different roles for the Fc epsilon RI gamma chain as a function of the receptor context

The high affinity immunoglobulin E receptor (Fc epsilon RI) and the B and T cell antigen receptors (TCR) are multimeric complexes containing subunits with cytoplasmic antigen recognition activation motifs (ARAMs). The presence of multiple motifs may be a way to amplify a single signal or provide independent activation modules. Here we have compared the signaling capacity of the same Fc epsilon RI gamma motif in the context of two different receptors, Fc epsilon RI and TCR/CD3, simultaneously reconstituted on the surface of the same zeta-deficient T cell line. Both reconstituted receptors mediate early (phosphorylation) and late (interleukin [IL]-2 release) signals. Mutation of the two tyrosine residues of ARAM gamma alters early signaling by both receptors, but the set of substrates phosphorylated via ARAM gamma is different for each receptor and is thus dependent on the receptor context. Furthermore, the mutations prevent Fc epsilon RI- but not TCR/CD3-mediated IL-2 release. These data demonstrate that ARAM gamma is necessary for allowing both receptors to phosphorylate the complete set of substrates, and that the CD3 complex, unlike the Fc epsilon RI beta chain, contains activation modules capable of compensating for the absence of a functional ARAM gamma in generating late signals such as IL-2 release.

Tobacco and occupation as risk factors in bladder cancer: a case-control study in southern Belgium

A pilot case-control study on bladder cancer, with population-based controls matched for each of 74 cases, has been conducted in two industrial areas of Southern Belgium in order to analyze the influence of tobacco use and occupation. Observed bladder cancer risk for smokers is more than 5 times higher than that for non-smokers, and the risk for people having an a priori hazardous occupation is about 3.5 times higher than that of other subjects. A dose-response relationship was found for tobacco exposure and duration of employment. It seems that the risk is increased in a log-linear way by these variables. Population attributable risks show that in 20 cases of bladder cancer, 17 could be explained by the two factors combined. This study also reveals an increased risk for metal workers, truck and engine drivers, coal-miners, and rubber and coal-tar workers. The risk for metal workers is specially high in the case of turners, metal fitters, blacksmiths, stokers and workers exposed to hot metal.