A human CD137×PD-L1 bispecific antibody promotes anti-tumor immunity via context-dependent T cell costimulation and checkpoint blockade

Immune checkpoint inhibitors demonstrate clinical activity in many tumor types, however, only a fraction of patients benefit. Combining CD137 agonists with these inhibitors increases anti-tumor activity preclinically, but attempts to translate these observations to the clinic have been hampered by systemic toxicity. Here we describe a human CD137xPD-L1 bispecific antibody, MCLA-145, identified through functional screening of agonist- and immune checkpoint inhibitor arm combinations. MCLA-145 potently activates T cells at sub-nanomolar concentrations, even under suppressive conditions, and enhances T cell priming, differentiation and memory recall responses. In vivo, MCLA-145 anti-tumor activity is superior to immune checkpoint inhibitor comparators and linked to recruitment and intra-tumor expansion of CD8 + T cells. No graft-versus-host-disease is observed in contrast to other antibodies inhibiting the PD-1 and PD-L1 pathway. Non-human primates treated with 100 mg/kg/week of MCLA-145 show no adverse effects. The conditional activation of CD137 signaling by MCLA-145, triggered by neighboring cells expressing >5000 copies of PD-L1, may provide both safety and potency advantages.

Adaptable antigen matrix platforms for peptide vaccination strategies and T cell-mediated anti-tumor immunity

Injection of antigenic peptides has been widely used as a vaccine strategy to boost T cell immunity. However, the poor immunogenicity of single peptides can potentially be strengthened through modification of the tertiary structure and the selection of the accompanying adjuvant. Here, we generated antigenic peptides into non-linear trimers by solid phase peptide synthesis, thereby enhancing antigen presentation by dendritic cells to CD8⁺ T cells in vitro and in vivo. CD8⁺ T cells from mice vaccinated with trimers showed an KLRG1⁺ effector phenotype and were able to recognize and kill antigen-expressing tumor cells ex vivo. Importantly, trimers outperformed synthetic long peptide in terms of T cell response even when equal number of epitopes were used for immunization. To improve the synthesis of trimers containing difficult peptide sequences, we developed a novel small molecule that functions as conjugation platform for synthetic long peptides. This platform , termed Antigen MAtriX (AMAX) improved yield, purity and solubility of trimers over conventional solid phase synthesis strategies. AMAX outperformed synthetic long peptides in terms of both CD8⁺ and CD4⁺ T cell responses and allowed functionalization with DC-SIGN-binding carbohydrates for in vivo dendritic cell targeting strategies, boosting T cell responses even further. Moreover, we show that agonistic CD40 antibody combined with MF59 (AddaVax) emulsion synergistically improves the antigen-specific T cell response of the AMAX in vivo. Also, tumor-associated antigens and neo-antigens could be incorporated in AMAX for tumor-specific CD8⁺ T cell responses. Importantly, immunization with a mix of neoantigen AMAX could reduce tumor growth in a pre-clinical syngeneic mouse model. Hence, we provide pre-clinical support for the induction of effector CD8⁺ T cells through the adaptable AMAX platform as easy implementable peptidic vaccination strategy against any antigen of choice, including neoantigens for anti-tumor immunity.

Abstract 539: A bispecific Fc-silenced IgG1 antibody (MCLA-145) requires PD-L1 binding to activate CD137

CD137 (4-1BB) is a transmembrane costimulatory receptor on T and NK cells that enhances adaptive immune responses and is a critical mediator of antitumor immunity. The development of CD137 targeted agents for cancer therapy has been hampered by on-target off-tumor toxicity in the case of agonist monospecific, bivalent mAbs or limited antitumor activity in the case of crosslinking mAbs. Here we have developed an Fc-silenced bispecific IgG1 antibody to CD137 and PD-L1 with monovalent binding specificity to each target. MCLA-145 drives transactivation of CD137 in the vicinity of cells expressing PD-L1, such as in the immunosuppressive tumor microenvironment. The degree of CD137 agonistic activity in T cells correlated with the expression level of PD-L1 on neighboring cells, as demonstrated in transactivation assays whereby reporter T cells were co-cultured with cells expressing different levels of PD-L1. PD-L1 expression as low as 6000 receptors per cell was sufficient to activate CD137 in neighboring T cells. In contrast, MCLA-145 blocked PD-1 signaling without requirement for CD137 binding in a PD-1/PD-L1 reporter assay. CD137 signaling was induced by MCLA-145 in multiple primary human immune cell assays including the mixed lymphocyte reaction, human PBMC, and whole blood SEB stimulation assays. MCLA-145 reversed T cell suppression mediated by M2 macrophages or Tregs, in vitro. In addition, MCLA-145 enhanced Ag-specific expansion and differentiation of human naïve CD8+ T cells in vitro.

In vivo, MCLA-145 treatment resulted in significant tumor immune activation and antitumor responses in two separate humanized mouse tumor models. In one model, human T cells expressing NY-ESO specific TCR were adoptively transferred to mice bearing A549 tumors which expressed NY-ESO antigen and human PD-L1. MCLA-145 treatment at 5 mg/kg resulted in 54% tumor growth inhibition (TGI) as compared to T cell only treated mice. In the tumors of MCLA-145 treated mice, the percentage of NY-ESO specific CD8+ T cells were significantly increased compared to controls. In a second model, mice engrafted with human CD34+ cells were implanted with the breast tumor cell line MDA-MB-231. MCLA-145 at 0.5 mg/kg and 5 mg/kg induced significant tumor growth inhibition (55 and 57% respectively) as compared to vehicle control or Fc-silenced huIgG1 controls. Additionally, two out of nine animals in the 5 mg/kg MCLA-145-treated group had complete tumor regression. MCLA-145 increased the number of infiltrating CD8+ T cells, as well as the percentage of central memory CD8+ T cells. The cured animals were then re-challenged with MDA-MB-231 tumor cells, and tumors of previously cured mice were rejected as compared to no growth inhibition in treatment-naïve CD34+ NSG mice. In conclusion, these data support the clinical evaluation of MCLA-145 as a novel, PD-L1 dependent CD137 agonist immune therapy.

Citation Format: Patrick Mayes, Paul Tacken, Steve Wang, Pieter-Fokko van Loo, Thomas Condamine, Hans van der Maaden, Eric Rovers, Steef Engels, Floris Fransen, Ashwini Kulkarni, Yao-bin Liu, Arpita Mondal, Leslie Hall, Soyeon Kim, Marina Martinez, Shaun O'Brien, Edmund Moon, Steven Albelda, Peggy Scherle, Gregory Hollis, Reid Huber, Mark Throsby, Cecile A. Geuijen. A bispecific Fc-silenced IgG1 antibody (MCLA-145) requires PD-L1 binding to activate CD137 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 539.

Outer membrane vesicles engineered to express membrane-bound antigen program dendritic cells for cross-presentation to CD8+ T cells

Outer membrane vesicles (OMVs) are vesicular nano-particles produced by Gram-negative bacteria that are recently being explored as vaccine vector. The fact that OMVs can be efficiently produced by a hypervesiculating Salmonella typhimurium strain, are packed with naturally-occurring adjuvants like lipopolysaccharides (LPS), and can be engineered to express any antigen of choice, makes them ideal candidates for vaccinology. However, it is unclear whether OMVs induce dendritic cell (DC)-mediated antigen-specific T cell responses and how immune activation is coordinated. Here, we show that OMVs induce maturation of human monocyte-derived DCs, murine bone marrow-derived DCs and CD11c+ splenic DCs. OMV-induced DC maturation was dependent on the presence of LPS and the myeloid differentiation primary response 88 (MyD88) adapter protein downstream of toll-like receptor signaling. Importantly, OMVs did not induce pyroptosis/cell death, but instead provided a significant survival benefit in DCs over non-stimulated DCs. OMVs displaying a sizeable ovalbumin fragment at the vesicle surface induce potent cross-presentation in BMDCs and splenic CD11c⁺ DCs to OTI CD8⁺ T cells, dependent on MyD88. Interestingly, the OMV-induced preference to cross-presentation was only partly dependent on the BATF3-dependent CD8a⁺ professional cross-presenting DC subset. Hence, an OMV-specific programming of DCs that induces maturation and provides a survival benefit for antigen presentation to T cells is identified. Additionally, for the first time, antigen-specific and potent cross-presentation of antigen-loaded OMVs to CD8⁺ T cells is demonstrated. These data provide mechanistical insight into the processes needed for the DC-mediated cross-presentation of OMV-derived antigens to CD8⁺ T cells with implications for therapeutic strategies. STATEMENT OF SIGNIFICANCE: Bacteria are primarily known to cause disease. However, recent research has focused on using engineered bacteria and its byproducts as vaccine agents. In particular, outer membrane vesicles (OMVs) have shown promise in eliciting potent immunity against a variety of pathogens. While most vaccines rely on the generation of antibodies, the control of viral replication and tumor growth is driven by cytotoxic CD8⁺ T cells induced by dendritic cells (DCs). As such, there is a dire need for vaccines that use DCs to elicit CD8⁺ T cell responses. Studying OMVs as engineered biomaterial and its interaction with DCs allows tailored induction of immunity. This study includes important findings on OMV-dendritic cell interactions and for the first time supports OMVs as vehicles for the induction of antigen-specific CD8⁺ T cell responses. Additionally, important mechanistical insight into the molecular pathways needed for the cross-presentation of OMV-derived antigens to CD8⁺ T cells is provided.

Abstract P4-12-06: Quality of life, fatigue, and subjective cognitive functioning immediately and 6 months after adjuvant chemotherapy in breast cancer patients

Background

The aim of this study was to examine quality of life (QoL), fatigue, and subjective cognitive functioning (SCF) after chemotherapy in breast cancer (BC) patients.

Methods

BC patients were recruited before chemotherapy (3 FEC+3 Tax, BC-Chemo) and compared with disease-specific controls (i.e., BC patients not receiving chemotherapy, BC-Controls) and healthy controls (HC) matched for age and education.

All participants completed questionnaires assessing QoL (using the Functional Assessment of Cancer Therapy – General Population), fatigue (using the Functional Assessment of Chronic Illness Therapy-Fatigue), and SCF (with the Cognitive Failure Questionnaire) at recruitment and 6 months later (i.e., one month after the end of chemotherapy). Follow-up data (1 year after recruitment) were available for BC-Chemo and HC only.

Difference scores were computed for each participant (i.e., score after 6 months/ 1 year minus score at baseline) and transformed when necessary so that negative scores would reflect decline over time (i.e., decreased QOL, increased fatigue, and increased cognitive complaints). These difference scores were analysed using independent t-tests (BC-Chemo vs BC-Controls on one hand, and BC-Chemo vs HC on the other hand).

Results

Eighteen BC- Chemo, 19 BC-Controls, and 20 HC completed the study (mean age = 49, 58, and 44 years, resp., p = 0.001, BC-Controls being significantly older).

Statistical analyses showed that, after chemotherapy, BC- Chemo patients showed significantly lower QoL, more fatigue, and declined SCF than both groups of controls (see Table 1).

However, 6 months later, no statistically significant differences were found between BC- Chemo and HC with respect to QoL and fatigue. Only SCF remained significantly lower in BC- Chemo.

Table 1.Mean Scores (standard deviations) for Quality of Life (QoL), Fatigue, and Subjective Cognitive Functioning (SCF) in Breast Cancer Patients treated with Chemotherapy (BC-Chemo) or not (BC-Controls) and Healthy Controls 6 months and 1 Year After Baseline BC-ChemoBC-ControlsHealthy ControlsQoL (FACT-GP)   6 months after baseline-5.8 (8)1.1 (8.7)*-0.3 (4.7)*1 year after baseline-5.3 (11.8) 0.2 (9.4)Fatigue (FACIT-F)   6 months after baseline-6.1 (11.1)0 (7.3)*-0.1 (3.8)*1 year after baseline-3.6 (10.3) -2.1 (6.5)SCF (CFQ)   6 months after baseline-7.4 (9.4)0.3 (10.9)*1 (5)*1 year after baseline-10.4 (13) 1.2 (6)**p < 0.05 (two-tailed independent t-tests vs BC-Chemo). Note. FACT-GP: Functional Assessment of Cancer Therapy – General Population (higher scores = greater QoL). FACIT-F: Functional Assessment of Chronic Illness Therapy-Fatigue Scale (higher scores = low fatigue). CFQ: Cognitive Failure Questionnaire (higher scores = greater subjective cognitive problems). All difference scores reflect decline over time.

Conclusions

Shortly after chemotherapy (i.e., 6 months after baseline), breast cancer patients experienced diminished QoL and increased fatigue compared to both disease-specific and healthy controls, but these differences were no longer significant 6 months later. In contrast, group differences in SCF were significant at both timepoints, suggesting long-lasting cognitive decline for patients receiving chemotherapy.

Citation Format: Mebis J, Censabella S, Engels S, Van Marsenille C, Orye G, Marquette S, Vansteelant L, Luyten D, Maes A, Noé L, Bulens P. Quality of life, fatigue, and subjective cognitive functioning immediately and 6 months after adjuvant chemotherapy in breast cancer patients [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 P4-12-06.

Historical atmospheric pollution trends in Southeast Asia inferred from lake sediment records

Fossil fuel combustion leads to increased levels of air pollution, which negatively affects human health as well as the environment. Documented data for Southeast Asia (SEA) show a strong increase in fossil fuel consumption since 1980, but information on coal and oil combustion before 1980 is not widely available. Spheroidal carbonaceous particles (SCPs) and heavy metals, such as mercury (Hg), are emitted as by-products of fossil fuel combustion and may accumulate in sediments following atmospheric fallout. Here we use sediment SCP and Hg records from several freshwater lentic ecosystems in SEA (Malaysia, Philippines, Singapore) to reconstruct long-term, region-wide variations in levels of these two key atmospheric pollution indicators. The age-depth models of Philippine sediment cores do not reach back far enough to date first SCP presence, but single SCP occurrences are first observed between 1925 and 1950 for a Malaysian site. Increasing SCP flux is observed at our sites from 1960 onward, although individual sites show minor differences in trends. SCP fluxes show a general decline after 2000 at each of our study sites. While the records show broadly similar temporal trends across SEA, absolute SCP fluxes differ between sites, with a record from Malaysia showing SCP fluxes that are two orders of magnitude lower than records from the Philippines. Similar trends in records from China and Japan represent the emergence of atmospheric pollution as a broadly-based inter-region environmental problem during the 20th century. Hg fluxes were relatively stable from the second half of the 20th century onward. As catchment soils are also contaminated with atmospheric Hg, future soil erosion can be expected to lead to enhanced Hg flux into surface waters.

Tumor sialylation impedes T cell mediated anti-tumor responses while promoting tumor associated-regulatory T cells

The increased presence of sialylated glycans on the tumor surface has been linked to poor prognosis, yet the effects on tumor-specific T cell immunity are hardly studied. We here show that hypersialylation of B16 melanoma substantially influences tumor growth by preventing the formation of effector T cells and facilitating the presence of high regulatory T cell (Treg) frequencies. Knock-down of the sialic acid transporter created "sialic acid low" tumors, that grew slower in-vivo than hypersialylated tumors, altered the Treg/Teffector balance, favoring immunological tumor control. The enhanced effector T cell response in developing "sialic acid low" tumors was preceded by and dependent on an increased influx and activity of Natural Killer (NK) cells. Thus, tumor hypersialylation orchestrates immune escape at the level of NK and Teff/Treg balance within the tumor microenvironment, herewith dampening tumor-specific T cell control. Reducing sialylation provides a therapeutic option to render tumors permissive to immune attack.

Size quantization of Dirac fermions in graphene constrictions

Quantum point contacts are cornerstones of mesoscopic physics and central building blocks for quantum electronics. Although the Fermi wavelength in high-quality bulk graphene can be tuned up to hundreds of nanometres, the observation of quantum confinement of Dirac electrons in nanostructured graphene has proven surprisingly challenging. Here we show ballistic transport and quantized conductance of size-confined Dirac fermions in lithographically defined graphene constrictions. At high carrier densities, the observed conductance agrees excellently with the Landauer theory of ballistic transport without any adjustable parameter. Experimental data and simulations for the evolution of the conductance with magnetic field unambiguously confirm the identification of size quantization in the constriction. Close to the charge neutrality point, bias voltage spectroscopy reveals a renormalized Fermi velocity of ∼1.5 × 10(6) m s(-1) in our constrictions. Moreover, at low carrier density transport measurements allow probing the density of localized states at edges, thus offering a unique handle on edge physics in graphene devices.

Antigen targeting to dendritic cells combined with transient regulatory T cell inhibition results in long-term tumor regression

Therapeutic vaccinations against cancer are still largely ineffective. Major caveats are inefficient delivery of tumor antigens to dendritic cells (DCs) and excessive immune suppression by Foxp3⁺ regulatory T cells (Tregs), resulting in defective T cell priming and failure to induce tumor regression. To circumvent these problems we evaluated a novel combinatorial therapeutic strategy. We show that tumor antigen targeting to DC-SIGN in humanized hSIGN mice via glycans or specific antibodies induces superior T cell priming. Next, this targeted therapy was combined with transient Foxp3⁺ Treg depletion employing hSIGNxDEREG mice. While Treg depletion alone slightly delayed B16-OVA melanoma growth, only the combination therapy instigated long-term tumor regression in a substantial fraction of mice. This novel strategy resulted in optimal generation of antigen-specific activated CD8⁺ T cells which accumulated in regressing tumors. Notably, Treg depletion also allowed the local appearance of effector T cells specific for endogenous B16 antigens. This indicates that antitumor immune responses can be broadened by therapies aimed at controlling Tregs in tumor environments. Thus, transient inhibition of Treg-mediated immune suppression potentiates DC targeted antigen vaccination and tumor-specific immunity.

Limitations to carrier mobility and phase-coherent transport in bilayer graphene

We present transport measurements on high-mobility bilayer graphene fully encapsulated in hexagonal boron nitride. We show two terminal quantum Hall effect measurements which exhibit full symmetry broken Landau levels at low magnetic fields. From weak localization measurements, we extract gate-tunable phase-coherence times τϕ as well as the inter- and intravalley scattering times τi and τ*, respectively. While τϕ is in qualitative agreement with an electron-electron interaction-mediated dephasing mechanism, electron spin-flip scattering processes are limiting τϕ at low temperatures. The analysis of τi and τ* points to local strain fluctuation as the most probable mechanism for limiting the mobility in high-quality bilayer graphene.

Graphene-based charge sensors

We discuss graphene nanoribbon-based charge sensors and focus on their functionality in the presence of external magnetic fields and high frequency pulses applied to a nearby gate electrode. The charge detectors work well with in-plane magnetic fields of up to 7 T and pulse frequencies of up to 20 MHz. By analyzing the step height in the charge detector's current at individual charging events in a nearby quantum dot, we determine the ideal operation conditions with respect to the applied charge detector bias. Average charge sensitivities of 1.3 × 10(-3)e Hz(-1/2) can be achieved. Additionally, we investigate the back action of the charge detector current on the quantum transport through a nearby quantum dot. By varying the charge detector bias from 0 to 4.5 mV, we can increase the Coulomb peak currents measured at the quantum dot by a factor of around 400. Furthermore, we can completely lift the Coulomb blockade in the quantum dot.

Fabrication of coupled graphene-nanotube quantum devices

We report on the fabrication and characterization of all-carbon hybrid quantum devices based on graphene and single-walled carbon nanotubes. We discuss both carbon nanotube quantum dot devices with graphene charge detectors and nanotube quantum dots with graphene leads. The devices are fabricated by chemical vapor deposition growth of carbon nanotubes and subsequent structuring of mechanically exfoliated graphene. We study the detection of individual charging events in the carbon nanotube quantum dot by a nearby graphene nanoribbon and show that they lead to changes of up to 20% of the conductance maxima in the graphene nanoribbon, acting as a well performing charge detector. Moreover, we discuss an electrically coupled graphene-nanotube junction, which exhibits a tunneling barrier with tunneling rates in the low GHz regime. This allows us to observe Coulomb blockade on a carbon nanotube quantum dot with graphene source and drain leads.

Electronic excited states in bilayer graphene double quantum dots

We report tunneling spectroscopy experiments on a bilayer graphene double quantum dot device that can be tuned by all-graphene lateral gates. The diameter of the two quantum dots are around 50 nm and the constrictions acting as tunneling barriers are 30 nm in width. The double quantum dot features additional energies on the order of 20 meV. Charge stability diagrams allow us to study the tunable interdot coupling energy as well as the spectrum of the electronic excited states on a number of individual triple points over a large energy range. The obtained constant level spacing of 1.75 meV over a wide energy range is in good agreement with the expected single-particle energy spacing in bilayer graphene quantum dots. Finally, we investigate the evolution of the electronic excited states in a parallel magnetic field.

Chronic and acute stress responses in Senegalese sole (Solea senegalensis): the involvement of cortisol, CRH and CRH-BP

The hypothalamus-pituitary-interrenal (HPI) axis is pivotal in the endocrine stress response of fish. Hypothalamic corticotropin-releasing hormone (CRH) initiates the endocrine stress response and stimulates the release of adrenocorticotropic hormone (ACTH) from the pituitary pars distalis, which in turn activates cortisol production and release by the interrenal cells of the head kidney. CRH activity depends on the levels of a specific CRH binding protein (CRH-BP). We have characterized the cDNAs coding for CRH and CRH-BP in Senegalese sole (Solea senegalensis) and investigated their mRNA expression in juveniles that were submitted to a protocol that involved exposure to a chronic stressor (viz. increased cultivation densities) followed by an acute stressor (viz. transfer to increased ambient salinity). Juveniles were cultivated at three densities (1.9, 4.7 and 9.8 kg/m(2)) for 33 days, and then exposed to an osmotic challenge that involved transfer from seawater (39‰ salinity, SW) to hypersaline seawater (55‰, HSW). The highest density imposed stress as indicated by elevated cortisol levels and CRH mRNA expression compared to fish stocked at low density. Fish kept at high density differentially responded to a posterior transfer to HSW; no cortisol or CRH response was seen, but osmoregulatory and metabolic parameters were affected. No differences in CRH-BP mRNA expression levels were found at different stocking densities; transfer to HSW enhanced expression in both low and high density stocked animals, suggesting that CRH-BP acts as a modulator of the acute stress response, not so of the chronic stress response. We conclude that stocking of Senegalese sole at high density is a stressful condition that may compromise the capacity to cope with subsequent stressors.

Sequential MR imaging and proton MR spectroscopy in patients who underwent recent detoxification for chronic alcoholism: correlation with clinical and neuropsychological data

BACKGROUND AND PURPOSE

Chronic alcohol abuse may cause neuropsychological disorders and result in brain atrophy. The purpose of this study was to evaluate the metabolic, morphologic, and functional cerebral changes in the early stage of abstinence from chronic alcoholism.

METHODS

Seventeen alcohol-dependent patients underwent MR imaging and MR spectroscopy on days 1 through 3 and days 36 through 39 of abstinence. In addition, psychological performance measures testing intelligence, concentration, attention, and memory were applied. Neuropsychological data were correlated with spectroscopic and volumetric results by using a Pearson's product moment correlation. The same measurements were also performed in 12 healthy, age-matched control subjects. Peak integral values for N-acetylaspartate (NAA) and choline (Cho) were referred to the peak integral value of creatine (Cr) as the internal reference.

RESULTS

NAA/Cr was decreased in the patients in both the frontal lobes and cerebellum immediately after cessation of drinking (days 1 through 3). After 36 to 39 days of abstinence, NAA/Cr had significantly increased in the patients and corresponded to performance on psychological tests. The Cho/Cr ratio was decreased in the cerebellum during early abstinence but was recovered on days 36 through 39. The patients had enlarged CSF spaces 1 to 3 days after detoxification, which decreased during sobriety. The extent of brain atrophy did not correspond to performance on psychological performance tests.

CONCLUSION

Regression of brain atrophy and metabolic recovery occurs at an early stage after abstinence from chronic alcohol abuse. MR spectroscopy findings return to normal metabolic levels within weeks after detoxification. The recovery of NAA/Cr is associated with improved performance on neuropsychological tests.

Abused women's concerns about safety and the therapeutic environment during psychiatric hospitalization

The purposes of this study were to identify the concerns of women who have a history of abuse regarding safety and the inpatient environment during psychiatric hospitalization, and to identify environmental changes they would like to see. A qualitative design was used to explore the women's concerns through semi-structured interviews. Instruments measuring sexual and physical abuse were administered. Of the 20 women recruited from 3 hospitals, 18 reported a history of sexual and/or physical abuse. One investigator interviewed the participants and one acted as recorder. After each interview, a list of identified concerns was generated; these concerns were raised in the next interview if not spontaneously brought up by the participant. Seventeen women reported feeling unsafe in mixed-gender units and said they would prefer segregated areas for programming and meals; 16 expressed concerns about nighttime routines and the traditional practices of restricting medications and contact with staff at night; 15 considered primary nursing extremely important to feeling understood and safe. The participants said they wanted to be heard and to be included in decision-making.

Caddisflies (Trichoptera: Hydropsychidae) used for evaluating water quality of large European rivers

In many European rivers, biodiversity has declined dramatically, and especially riverine insects have disappeared during the past decades. It remains unclear whether poor water quality or deteriorated habitats are limiting the distribution of sensitive aquatic insects in these rivers. The aim of this study, therefore, was to find out if water quality alone is limiting the distribution of these insects in rivers that have suffered from anthropogenic disturbances. To this purpose, caddisflies of the genus Hydropsyche, which are representative riverine insect species, were incubated in two large European rivers, the Rhine and the Meuse. Survival of caddisflies in the River Rhine was fairly high, while there was almost no survival in the River Meuse in three out of five field experiments. The incubations of Hydropsyche in the River Meuse provide evidence that even adequate structural habitat would be insufficient for the reestablishment of Hydropsyche species. The factors limiting the distribution of Hydropsyche species change with the changing constitution of the water; there is not one (group of) compound(s) responsible for the poor water quality. Besides chemical factors, physical factors (like oxygen and current velocity) may be limiting in the River Meuse for Hydropsyche species.

Performance evaluation of the FACSCount System: a dedicated system for clinical cellular analysis

Flow cytometers are instruments that can determine multiparameter data simultaneously and have a great potential in providing unique information about cells. The FACSCount System is designed as the first dedicated flow cytometer for the clinical laboratory. Its current configuration provides CD4, CD8, and CD3 absolute counts from 100 microliters of whole blood. Adapting the FACSCount System to the clinical setting are minimal sample handling, lysis free cell preparation, automated fluorescence gating, built-in calibrated reference beads, and appropriate error code reporting. Quality control checks ensure that reported CD4 counts, important for clinical follow-up and patient management, are accurate, precise, and reproducible across instruments over time.

Localization and actions of transforming growth factor-beta s in the embryonic nervous system

We present evidence for unique localization and specific biological activities for transforming growth factor-beta s (TGF-beta s) 2 and 3, as compared to TGF-beta 1, in the nervous system of the 12-18 day mouse embryo. Each TGF-beta isoform was localized immunohistochemically by specific antibodies raised to peptides corresponding to unique sequences in the respective TGF-beta proteins. Staining for TGF-beta 1 was principally in the meninges, while TGF-beta s 2 and 3 co-localized in neuronal perikarya and axons, as well as in radial glial cells. In the central nervous system, staining was most prominent in zones where neuronal differentiation occurs and less intense in zones of active proliferation, while in the peripheral nervous system, many nerve fibers as well as their cell bodies were strongly immunoreactive for TGF-beta s 2 and 3. Functionally, we have also found that in the presence of an extract of chick eye tissue, TGF-beta s 2 and 3 inhibit survival of cultured embryonic chick ciliary ganglionic neurons in a dose-dependent fashion; TGF-beta 1 shows no inhibitory effects. Our data suggest that TGF-beta s 2 and 3 may play a role in regulation of neuronal migration and differentiation, as well as in glial cell proliferation and differentiation.