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Photonic power converters (PPCs), which convert narrow-band light to electricity, are essential components in power-by-light systems. When designed for telecommunications wavelengths such as the O-band, near 1310 nm, the devices are well-suited to power-over-fiber applications. Despite the potential for very high power conversion efficiencies ( >50% ), PPCs can be adversely affected by high-intensity nonuniform illumination conditions. In this work, we characterized two O-band PPC designs based on: high-quality InGaAsP absorber material lattice-matched to an InP substrate, and metamorphic InGaAs absorber material lattice-mismatched to a GaAs substrate, a more cost-effective and scalable alternative. We measured each device under O-band laser illumination with five beam profiles having peak-to-average ratios ranging from 2 to 11. Both devices were insensitive to the beam uniformity for input illumination with average irradiance below 2 W/cm 2 over their 5.4-mm 2 active areas, but exhibited better open-circuit voltages under larger, more uniform illumination profiles at higher incident powers. Measured efficiencies reached 52.8% and 48.7% for the lattice-matched and mismatched devices, respectively. Distributed circuit modeling results suggested that both lateral conduction losses and localized heating effects were responsible for the measured dependence on beam-size. Our work demonstrates the potential for O-band PPCs, presenting two highly efficient designs suitable for powering devices requiring ≲250 mW, with an appropriate illumination profile.

Genetic vaccination using naked plasmid DNA is an immunization strategy both against infectious diseases and cancer.In order to improve efficacy of DNA vaccines, particularly in large animals and humans, different strategies have been pursued. These vaccination strategies are based on different application routes, schedules and coexpression of immunomodulatory molecules as adjuvants. Our mouse tumor model offers the possibility to investigate Her2/neu DNA vaccines in different settings, that is, intramuscular or intradermal application with or without coexpression of adjuvants. The immunogenicity of predicted peptides for Her2/neu specific memory T cells were screened and confirmed after intramuscular and intradermal application. Protection from tumor growth in tumor challenge experiments and both T cell and humoral immune responses against Her2/neu peptides are used as surrogate parameters for vaccine efficacy.

Although safety concerns preclude the use of live attenuated HIV vaccines in humans, they provide a useful system for identifying the elusive correlates of protective immunity in the SIV/macaque animal model. However, a number of pieces of evidence suggest that protection may result from prior occupancy of susceptible target cells by the vaccine virus rather than the immune response. To address this, we developed a Nef-deletion variant of an RT-SHIV whose active replication could be shut off by treatment with RT-inhibitors. Groups of macaques were inoculated with the ∆Nef-RT-SHIV and immune responses allowed to develop before antiretroviral treatment and subsequent challenge with wild-type SIVmac239. Vaccinated animals either resisted infection fully or significantly controlled the subsequent viremia. However, there was no difference between animals undergoing replication of the vaccine virus and those without. This strongly suggests that competition for available target cells does not play a role in protection.

The HERV-K(HML-2) family is the most recent addition to the collection of human endogenous retroviruses. It comprises proviruses that encode functional proteins that can assemble into replication defective particles carrying the envelope protein. Using a reconstituted HERV-K113 envelope sequence, we have analyzed its ability to mediate entry into a set of 33 cell lines from 10 species. Of these, 30 were permissive, demonstrating an amphotropism consistent with a broad expression of receptor protein(s). In an initial effort to identify a receptor for HERV-K(HML-2) we investigated whether transferrin receptor 1 and hyaluronidase 2, known cellular receptors of the closely related betaretroviruses mouse mammary tumor virus (MMTV) and Jaagsiekte sheep retrovirus (JSRV), could facilitate HERV-K(HML-2) entry. However, neither of these proteins could serve as a receptor for HERV-K(HML-2). Moreover, during attempts to further characterize the tropism of HERV-K(HML-2), we identified a cellular activity that inhibits infection at a post-entry, pre-integration step.

A hydrofluoric-acid (HF)-free hydrogen plasma dry etching process prior to the deposition of intrinsic amorphous silicon onto thin n-type planar Czochralski silicon wafers is developed. The influence of substrate temperature, hydrogen flow rate, and power density on the passivation quality is investigated. Advanced characterization using spectroscopic ellipsometry and transmission electron microscopy shows the impact of the etching conditions, especially the temperature and gas flow rates, on the surface quality and interface properties. It is found that the native oxide can only be removed effectively when wafers are subjected to higher temperature or lower hydrogen flow rate. The hydrogen, oxygen, and carbon concentration profiles at the a -Si/ c -Si interface of the plasma-etched samples are studied and compared with the traditionally HF cleaned interface to gain a better understanding of the reasons for the superior passivation quality.

Initial indications that retroviruses are connected to neoplastic transformation were seen more than a century ago. This concept has also been tested for endogenized retroviruses (ERVs) that are abundantly expressed in many transformed cells. In healthy cells, ERV expression is commonly prevented by DNA methylation and other epigenetic control mechanisms. ERVs are remnants of former exogenous forms that invaded the germ line of the host and have since been vertically transmitted. Several examples of ERV-induced genomic recombination events and dysregulation of cellular genes that contribute to tumor formation have been well documented. Moreover, evidence is accumulating that certain ERV proteins have oncogenic properties. In contrast to these implications for supporting cancer induction, a recent string of papers has described favorable outcomes of increasing human ERV (HERV) RNA and DNA abundance by treatment of cancer cells with methyltransferase inhibitors. Analogous to an infecting agent, the ERV-derived nucleic acids are sensed in the cytoplasm and activate innate immune responses that drive the tumor cell into apoptosis. This “viral mimicry” induced by epigenetic drugs might offer novel therapeutic approaches to help target cancer cells that are normally difficult to treat using standard chemotherapy. In this review, we discuss both the detrimental and the new beneficial role of HERV reactivation in terms of its implications for cancer.

Hydrogenated intrinsic amorphous silicon suboxide thin films deposited onto c -Si wafers by decomposing hydrogen, silane, and carbon dioxide in an industrial remote inductively coupled plasma tool are studied. Compared with intrinsic amorphous silicon deposited in the same tool, this material displays an improved process temperature window and excellent surface passivation quality, which is important for industrialization. The wide process window of over 200 °C (100 to 350 °C) mainly results from the slow depletion of H atoms at elevated temperature due to a suppressed epitaxial growth, whereas the excellent passivation quality is due to a much higher H content in the film compared with amorphous silicon. The temperature stability is further supported by a study using a high-resolution transmission electron microscopy. Under the optimal condition, the amorphous silicon suboxide demonstrates an effective minority carrier lifetime of over 4.7 ms on planar n-type 1-Ω · cm Czochralski silicon wafers, which is equivalent to an effective surface recombination velocity of less than 1.7 cm/s, and an implied open-circuit voltage of 741 mV.

In this work, hydrogen plasma etching of surface oxides was successfully accomplished on thin (∼100 µm) planar n-type Czochralski silicon wafers prior to intrinsic hydrogenated amorphous silicon [a-Si:H(i)] deposition for heterojunction solar cells, using an industrial inductively coupled plasma-enhanced chemical vapour deposition (ICPECVD) platform. The plasma etching process is intended as a dry alternative to the conventional wet-chemical hydrofluoric acid (HF) dip for solar cell processing. After symmetrical deposition of an a-Si:H(i) passivation layer, high effective carrier lifetimes of up to 3.7 ms are obtained, which are equivalent to effective surface recombination velocities of 1.3 cm s–1 and an implied open-circuit voltage (Voc) of 741 mV. The passivation quality is excellent and comparable to other high quality a-Si:H(i) passivation. High-resolution transmission electron microscopy shows evidence of plasma-silicon interactions and a sub-nanometre interfacial layer. Using electron energy-loss spectroscopy, this layer is further investigated and confirmed to be hydrogenated suboxide layers. (© 2015 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim)

The HERV-K(HML-2) family contains the most recently integrated and best preserved endogenized proviral sequences in the human genome. All known elements have nevertheless been subjected to mutations or deletions that render expressed particles non-infectious. Moreover, these post-insertional mutations hamper the analysis of the general biological properties of this ancient virus family. The expression of consensus sequences and sequences of elements with reverted post-insertional mutations has therefore been very instrumental in overcoming this limitation. We investigated the particle morphology of a recently reconstituted HERV-K113 element termed oriHERV-K113 using thin-section electron microscopy (EM) and could demonstrate that strong overexpression by substitution of the 5'LTR for a CMV promoter and partial codon optimization altered the virus assembly type and morphology. This included a conversion from the regular C-type to an A-type morphology with a mass of cytoplasmic immature cores tethered to the cell membrane and the membranes of vesicles. Overexpression permitted the release and maturation of virions but reduced the envelope content. A weaker boost of virus expression by Staufen-1 was not sufficient to induce these morphological alterations.

We present an alternative method of depositing a high-quality passivation film for heterojunction silicon wafer solar cells, in this paper. The deposition of hydrogenated intrinsic amorphous silicon suboxide is accomplished by decomposing hydrogen, silane, and carbon dioxide in an industrial remote inductively coupled plasma platform. Through the investigation on CO2partial pressure and process temperature, excellent surface passivation quality and optical properties are achieved. It is found that the hydrogen content in the film is much higher than what is commonly reported in intrinsic amorphous silicon due to oxygen incorporation. The observed slow depletion of hydrogen with increasing temperature greatly enhances its process window as well. The effective lifetime of symmetrically passivated samples under the optimal condition exceeds 4.7 ms on planarn-type Czochralski silicon wafers with a resistivity of 1 Ωcm, which is equivalent to an effective surface recombination velocity of less than 1.7 cms−1and an implied open-circuit voltage (Voc) of 741 mV. A comparison with several high quality passivation schemes for solar cells reveals that the developed inductively coupled plasma deposited films show excellent passivation quality. The excellent optical property and resistance to degradation make it an excellent substitute for industrial heterojunction silicon solar cell production.

Attenuated Salmonella is an approved oral life vaccine that is currently entering pre-clinical cancer vaccination studies as a promising DNA carrier. In a syngeneic mouse model for neuroblastoma, oral gavage of Salmonella typhimurium (SL7207) carrying recent generated survivin DNA vaccines induced a stronger cellular anti-NB immune response than gene gun application or injection of lentivirally transduced bone marrow-derived DCs. The level of Salmonella-associated side effects was not significant as indicated by unaffected survivin-mediated hematopoiesis and wound healing. We believe that our findings provide an important baseline to translate Salmonella-based DNA vaccination into a clinical application for neuroblastoma.

Passivated emitter and rear cells (PERC) are considered to be the next generation of industrial-type screen-printed silicon solar cells. Deposition methods for rear passivation layers have to meet both the high-throughput and low-cost requirements of the PV industry in combination with high-quality surface passivation properties. In this paper, we evaluate and optimise a novel deposition technique for AlO x passivation layers by applying an inductively coupled plasma (ICP) plasma-enhanced chemical vapour deposition (PECVD) process. The ICP AlO x deposition process enables high deposition rates up to 5 nm/s as well as excellent surface recombination velocities below 10 cm/s after firing. A fixed negative charge of −4×10 12 cm −2 is measured for ICP AlO x single layers with an interface state density of 11.0×10 11 eV −1 cm −2 at midgap position. When applied to PERC solar cells the ICP AlO x layer is capped with a PECVD SiN y layer. We achieve independently confirmed conversion efficiencies of up to 20.1% for large-area (15.6×15.6 cm 2 ) PERC solar cells with screen-printed metal contacts and ICP AlO x /SiN y rear side passivation on standard boron-doped Czochralski-grown silicon wafers. The internal quantum efficiency reveals an effective rear surface recombination velocity S rear of (90±30) cm/s and an internal rear reflectance R b of (91±1)% which demonstrates the excellent rear surface passivation of the ICP AlO x /SiN y layer stack.

DNA vaccines are potential tools for the induction of immune responses against both infectious disease and cancer. The dermal application of DNA vaccines is of particular interest since the epidermal and dermal layers of the skin are characterized by an abundance of antigen-presenting cells (APCs). The aim of our study was to compare tumor protection as obtained by two different methods of intradermal DNA delivery (gene gun and jet injector) in a well-established HER2/neu mouse tumor model. BALB/c mice were immunized twice with a HER2/neu-coding plasmid by gene gun or jet injector. Mice were then subcutaneously challenged with HER2/neu+ syngeneic D2F2/E2 tumor cells. Protection against subsequent challenges with tumor cells as well as humoral and T-cell immune responses induced by the vaccine were monitored. Gene gun immunization was far superior to jet injector both in terms of tumor protection and induction of HER2/neu-specific immune responses. After gene gun immunization, 60% of the mice remained tumo...

The aim of this study was to evaluate the efficacy of the chemokine CCL19 (ELC) as an adjuvant for intradermal gene gun delivery of Her2/neu DNA and to investigate the role of B cells in CCL19-mediated enhancement of immune responses. Balb/c mice were immunized intramuscularly (i.m.) on days 1 and 15 with plasmid DNA (pDNA) (100 μg DNA) or intradermally (i.d.) by gene gun delivery (1-2 μg DNA). Administration of pDNA encoding Her2/neu (pDNA(Her2/neu) was compared with pDNA(Her2/neu) plus pDNA(CCL19), pDNA(CCL19), mock vector or uncoated gold particles/phosphate-buffered saline (PBS). Tumor challenge was performed subcutaneously on day 25 with syngeneic Her2/neu(+) tumor cells (D2F2/E2). Intradermal immunization by gene gun led to an enhancement of tumor protection by the DNA vaccine as compared with i.m. immunization. The protective effect of the vaccine was further enhanced by coadministration of pDNA(CCL19) both after i.m. and i.d. immunization. Tumor protection was associated with Her2/neu-specific T cell and humoral immune responses. Experiments in B-cell-deficient μMT mice showed that B cells are crucial for CCL19-mediated enhancement of tumor rejection, most likely as antigen-presenting B cells. DNA vaccines against Her2/neu may play a future role in the treatment of Her2/neu-positive breast cancer patients in a clinical situation of minimal residual disease.

The detection or quantification of retroviruses is often achieved using an antigen-capture ELISA (AC-ELISA) that targets the Gag capsid (CA) protein. We report here the development of an AC-ELISA specific for the p27-CA protein of HERV-K(HML-2). A monoclonal p27-specific antibody is used for capture and a polyclonal anti-p27-CA immune serum generated in rabbits serves for detection. The assay was shown to be specific for HERV-K(HML-2), showing no evidence of cross reactivity with the human retroviruses HIV-1, HIV-2 and HTLV-1 or with XMRV (as a model non-human gammaretrovirus). Using purified recombinant antigen, the limit of detection was shown to be 130 pg/ml. The AC-ELISA can be used to quantify HERV-K(HML-2) expression in teratocarcinoma cell lines and to normalize HERV particles generated by transfecting HEK 293T cells with full-length molecular clones. This novel AC-ELISA also proved useful in studies of virus regulation, for example in demonstrating that HERV-K(HML-2) expression is dramatically enhanced by overexpression of Staufen-1, a binding partner of the HERV-K(HML-2) Rec protein. This specific and sensitive HERV-K(HML-2) AC-ELISA will be a useful tool for investigating many aspects of endogenous retroviruses, from basic research to the role they may play in human diseases or as a surrogate marker for particular diseases.

Retroviruses are well known pathogens of mammals, birds and fish. Their potential to induce cancer in chickens was already described almost 100 years ago and murine retroviruses have been a subject of study for 50 years. The first human retroviruses, HTLV and HIV, were discovered more than 30 years ago, surprising researchers and physicians by the profound differences in the diseases they cause. HTLV-1 is able to induce, after decades of infection, lymphomas/leukemia or neuroimmune disorders whereas untreated HIV infection leads almost inevitably to AIDS. The recently described XMRV (xenotropic murine leukemia virus-related virus) appeared to possess many of the features known for HTLV and was regarded by some to be the third human retrovirus. However, recent publications by Knox et al. [1] and Paprotka et al. [2] have shed new light on this gammaretrovirus. Knox and colleagues clearly demonstrate that XMRV is absent in patients belonging to a chronic fatigue syndrome cohort who had previously been reported to be XMRV-positive [3]. This supports the growing suspicion that laboratory contamination was responsible for the postulated link between XMRV and the disease. Furthermore, Paprotka et al’s identification of XMRV’s origin and the phylogenetic analysis of known XMRV sequences are further nails in the coffin to the notion that XMRV is a clinically relevant infectious human retrovirus.

The inhibitor of apoptosis protein survivin is highly expressed in neuroblastoma (NB) and survivin-specific T cells were identified in Stage 4 patients. Therefore, we generated a novel survivin minigene DNA vaccine (pUS-high) encoding exclusively for survivin-derived peptides with superior MHC class I (H2-K(k)) binding affinities and tested its efficacy to suppress tumor growth and metastases in a syngeneic NB mouse model. Vaccination was performed by oral gavage of attenuated Salmonella typhimurium SL7207 carrying pUS-high. Mice receiving the pUS-high in the prophylactic setting presented a 48-52% reduction in s.c. tumor volume, weight and liver metastasis level in contrast to empty vector controls. This response was as effective as a survivin full-length vaccine and was associated with an increased target cell lysis, increased presence of CD8(+) T-cells at the primary tumor site and enhanced production of proinflammatory cytokines by systemic CD8(+) T cells. Furthermore, depletion of CD8(+) but not CD4(+) T-cells completely abrogated the pUS-high mediated primary tumor growth suppression, demonstrating a CD8(+) T-cell mediated effect. Therapeutic vaccination with pUS-high led to complete NB eradication in over 50% of immunized mice and surviving mice showed an over 80% reduction in primary tumor growth upon rechallenge in contrast to controls. In summary, survivin-based DNA vaccination is effective against NB and the rational minigene design provides a promising approach to circumvent potentially hazardous effects of using full length antiapoptotic genes as DNA vaccines.

Applications of such optical technologies as vision care, digital imaging or data communication play an important role in our daily life. Manipulation of light is mainly done using optical lenses. Besides mineral lenses, transparent plastic materials are increasingly gaining in importance. The optical and mechanical properties of lenses are crucially improved by high-quality coatings. This includes primarily anti-reflective coatings to enhance light transmission, hard coats to improve scratch resistance of sensitive plastic substrates and finally clean coats to keep the lenses from catching dust and make cleaning easier. In the following we present modern vacuum coating technologies for the industrial refinement of optical substrates. The focus is on the coating of plastic eyeglass lenses using a revolutionary inline technology. On the one hand, the technology merges all coating steps in a fully automated system, and, on the other hand, enables the flexible combination of different layer stacks necessary for RX-production of ophthalmic lenses. The coating system OPTICUS gives access to this unique inline technology. The design of the OPTICUS is described in the last chapter.

A large proportion of the human genome consists of endogenous retroviruses, some of which are well preserved, showing transcriptional activity, and expressing retroviral proteins. The HERV-K(HML-2) family represents the most intact members of these elements, with some having open and intact reading frames for viral proteins and the ability to form virus-like particles. Although generally suppressed in most healthy tissues by a variety of epigenetic processes and antiviral mechanisms, there is evidence that some members of this family are (at least partly) still active - particularly in certain stem cells and various tumors. This raises the possibility of their involvement in tumor induction or in developmental processes. In recent years, many new insights into this fascinating field have been attained, and this review focuses on new discoveries about coevolutionary events and intracellular defense mechanisms against HERV-K(HML-2) activity. We also describe what might occur when these mechanisms fail or become modulated by viral proteins or other viruses and discuss the new vistas opened up by the reconstitution of ancestral viral proteins and even complete HML-2 viruses.

Background Although human T-lymphotropic virus (HTLV) is transmitted via the same routes as human immunodeficiency virus (HIV), its worldwide seroprevalence differs drastically because HTLV is transmitted mainly via infected cells rather than free virus. The sharing of needles and other equipment places people who inject drugs (PWID) at particularly high-risk for such blood-borne diseases. Methods To validate the methodology used to process and analyze the dried blood spots (DBS) utilized in the study, dried serum spots (DSS) with dilutions of sera from known HTLV infected individuals were analyzed by ELISA and Western blot. DBS collected between 2011 and 2015 from 2,077 PWID in eight German cities recruited by respondent-driven sampling were tested for HTLV-specific antibodies. Results The validation demonstrated that the use of DSS allowed identification of samples with even low titers of HTLV-specific antibodies, although a confirmatory Western blot with an additional venous blood sample would often be required. Despite numerous HIV and HCV positive individuals being identified within the study population, none tested positive for HTLV. Conclusion While the HIV and HCV prevalences in German PWID are comparable to those in other European countries, the very low prevalence of HTLV reflects the situation in the general population.

One of the most promising advanced solar cell designs for x :H(i) have yielded very good results compatible with high-voltage HET solar cells, with the passivation quality of a-SiO x :H(i) being consistently higher, and far less sensitive to the deposition temperature compared to a-Si:H(i). In fact, a-SiO x :H(i) has a stable process window of more than 200°C that is suitable for the production environment. The wider process window can be attributed to suppressed epitaxial growth and incubation layer thickness in the a-SiO x :H(i) layer at high deposition temperatures.

Xenotropic murine leukemia virus-related gammaretrovirus (XMRV) has been recently associated with prostate cancer and chronic fatigue syndrome. To identify nucleic acid sequences, we examined respiratory secretions by using PCR. XMRV-specific sequences were detected in 2%-3% of samples from 168 immunocompetent carriers and approximately 10% of samples from 161 immunocompromised patients.

Retroviruses that have the ability to infect germ line cells can become an integral and inherited part of the host genome. About 8% of the human chromosomal DNA consists of sequences derived from infections by retroviruses that presumably circulated 2–40 millions of years ago, and some elements are actually much older. Post-insertional recombinations, deletions, and mutations have rendered all known human endogenous retroviruses (HERVs) non-infectious. However some, particularly the most recently acquired proviruses of the HERV-K(HML-2) family, can expresses viral proteins and produce viral particles. In this review we will first discuss the major aspects of the endogenization process and peculiarities of the different HERV-K families. We will then focus on the genes and proteins encoded by HERV-K(HML-2) as well as inactivation of these proviruses by postinsertional mutations and their inhibition by antiretroviral factors. After describing the evolutionary interplay between host and endogenous retrovirus we will delve deeper into the currently limited understanding of HERV-K and its possible association with disease, particularly tumorigenesis.

The human endogenous retrovirus family HERV-K(HML-2) Rec protein is an RNA transport factor that enhances nuclear export of intron-containing retroviral transcripts. Using the yeast two-hybrid approach, we have newly identified human Staufen-1 as a Rec-interacting protein. The interaction was confirmed by coimmunoprecipitation experiments, and the relevant site in Staufen-1 has been mapped to double-stranded RNA binding domain 4 (RBD4). Staufen-1 is in several aspects functionally related to retroviral RNA transport proteins. It binds mRNAs and targets its ribonuclear cargo to polysomes for efficient translation. We observed an accumulation of Staufen-1 in the nucleus of Rec-expressing cells and colocalization in the nucleoli as well as in the cytoplasm. Overexpression of Staufen-1 resulted in a 5-fold enhancement in nuclear export and/or translation of unspliced HERV-K(HML-2) viral RNAs in the presence of Rec and its Rec-responsive element (RcRE) binding site together with a clear increase in virus production. Staufen-1 was previously shown to interact with the Gag protein of HIV-1, promoting Gag oligomerization and RNA encapsidation. We demonstrate here that Staufen-1 also binds to the Gag protein of HERV-K(HML-2). Under stress conditions, Rec colocalizes with Staufen-1 in stress granules in cells that express viral RNA but not in mRNA-decay-related processing bodies. Our results suggest a new role for Staufen-1 as a cellular Rec and HERV-K(HML-2) Gag cofactor.

DNA immunization is a convenient and effective way of inducing a specific antibody response. In mammals, co-administration of vectors encoding immunostimulatory cytokines can enhance the humoral response resulting in elevated antibody titers. We therefore set out to investigate the effect using avian interleukin 1β (IL-1β) and avian interleukin 6 (IL-6) as genetic adjuvants when immunizing laying hens. A BoNT A1 holotoxoid DNA immunogen carrying two inactivating mutations was evaluated for its ability to induce a specific and sustained IgY antibody response. Both the holotoxoid and the cytokine sequences were codon-optimized. In vitro, the proteins were efficiently expressed in transfected HEK 293T cells and the cytokines were secreted into the culture supernatants. Whereas eggs from hens immunized via gene gun using a prime boost strategy showed no differences in their total IgY content, the specific αBoNT A1 response was slightly elevated up to 1.4× by the IL-1β adjuvant vector and increased by 3.8× by the IL-6 vector. Finally, although hens receiving the IL-1β adjuvant had laying capacities above the average, hens receiving the IL-6 adjuvant experienced laying problems.

BACKGROUND: We recently published the rare detection of xenotropic murine leukemia virus-related virus (XMRV) (1/105) in prostate cancer (PCA) tissue of patients in Northern Europe by PCR. The controversial discussion about the virus being detected in PCA tissue, blood samples from patients suffering from chronic fatigue syndrome (CFS), as well as from a significant number of healthy controls prompted us to deepen our studies about detection of XMRV infection applying different detection methods (PCR, cocultivation and immunohistochemistry [IHC]). METHODOLOGY/PRINCIPAL FINDINGS: Peripheral blood mononuclear cells (PBMCs) from 92 PCA and 7 healthy controls were isolated, PHA activated and cocultivated with LNCaP cells for up to 8 weeks. Supernatant of these cells was applied to a reporter cell line, DERSE-iGFP. Furthermore, the PBMCs and cocultivated LNCaP cells were tested for the presence of XMRV by PCR as well as Western Blot analysis. While all PCR amplifications and Western Blot analyses were negative for signs of XMRV infection, DERSE-iGFP cells displayed isolated GFP positive cells in three cases. In all three cases XMRV presence could not be confirmed by PCR technology. In addition, we performed XMRV specific IHC on PCA tissue sections. Whole tissue sections (n = 20), as well as tissue microarrays (TMA) including 50 benign prostate hyperplasia (BPH), 50 low grade and 50 high grade PCA sections and TMAs including breast cancer, colon cancer and normal tissues were stained with two XMRV specific antisera. XMRV protein expression was not detected in any cancer sections included. One BPH tissue displayed XMRV specific protein expression in random isolated basal cells. CONCLUSION: We were unable to conclusively detect XMRV in the blood from PCA patients or from healthy controls and there is no conclusive evidence of XMRV protein expression in PCA, breast cancer and colon cancer tissue sections tested by IHC staining.

BackgroundXenotropic murine leukemia virus-related virus (XMRV), a novel human retrovirus originally identified in prostate cancer tissues, has recently been associated with chronic fatigue syndrome (CFS), a disabling disease of unknown etiology affecting millions of people worldwide. However, several subsequent studies failed to detect the virus in patients suffering from these illnesses or in healthy subjects. Here we report the results of efforts to detect antibody responses and viral sequences in samples from a cohort of German CFS and relapsing remitting multiple sclerosis (MS) patients with fatigue symptoms.MethodologyBlood samples were taken from a cohort of 39 patients fulfilling the Fukuda/CDC criteria (CFS), from 112 patients with an established MS diagnosis and from 40 healthy donors. Fatigue severity in MS patients was assessed using the Fatigue Severity Scale (FSS). Validated Gag- and Env-ELISA assays were used to screen sera for XMRV antibodies. PHA-activated PBMC were cultured for seven days in the presence of IL-2 and DNA isolated from these cultures as well as from co-cultures of PBMC and highly permissive LNCaP cells was analyzed by nested PCR for the presence of the XMRV gag gene. In addition, PBMC cultures were exposed to 22Rv1-derived XMRV to assess infectivity and virus production.ConclusionNone of the screened sera from CFS and MS patients or healthy blood donors tested positive for XMRV specific antibodies and all PBMC (and PBMC plus LNCaP) cultures remained negative for XMRV sequences by nested PCR. These results argue against an association between XMRV infection and CFS and MS in Germany. However, we could confirm that PBMC cultures from healthy donors and from CFS patients can be experimentally infected by XMRV, resulting in the release of low levels of transmittable virus.

Background XMRV, a xenotropic murine leukemia virus (MuLV)-related virus, was recently identified by PCR testing in 67% of persons with chronic fatigue syndrome (CFS) and in 3.7% of healthy persons from the United States. To investigate the association of XMRV with CFS we tested blood specimens from 51 persons with CFS and 56 healthy persons from the US for evidence of XMRV infection by using serologic and molecular assays. Blinded PCR and serologic testing were performed at the US Centers for Disease Control and Prevention (CDC) and at two additional laboratories. Results Archived blood specimens were tested from persons with CFS defined by the 1994 international research case definition and matched healthy controls from Wichita, Kansas and metropolitan, urban, and rural Georgia populations. Serologic testing at CDC utilized a Western blot (WB) assay that showed excellent sensitivity to MuLV and XMRV polyclonal or monoclonal antibodies, and no reactivity on sera from 121 US blood donors or 26 HTLV-and HIV-infected sera. Plasma from 51 CFS cases and plasma from 53 controls were all WB negative. Additional blinded screening of the 51 cases and 53 controls at the Robert Koch Institute using an ELISA employing recombinant Gag and Env XMRV proteins identified weak seroreactivity in one CFS case and a healthy control, which was not confirmed by immunofluorescence. PCR testing at CDC employed a gag and a pol nested PCR assay with a detection threshold of 10 copies in 1 ug of human DNA. DNA specimens from 50 CFS patients and 56 controls and 41 US blood donors were all PCR-negative. Blinded testing by a second nested gag PCR assay at the Blood Systems Research Institute was also negative for DNA specimens from the 50 CFS cases and 56 controls. Conclusions We did not find any evidence of infection with XMRV in our U.S. study population of CFS patients or healthy controls by using multiple molecular and serologic assays. These data do not support an association of XMRV with CFS.

Background A novel gammaretrovirus named xenotropic murine leukemia virus-related virus (XMRV) has been recently identified and found to have a prevalence of 40% in prostate tumor samples from American patients carrying a homozygous R462Q mutation in the RNaseL gene. This mutation impairs the function of the innate antiviral type I interferon pathway and is a known susceptibility factor for prostate cancer. Here, we attempt to measure the prevalence of XMRV in prostate cancer cases in Germany and determine whether an analogous association with the R462Q polymorphism exists. Results 589 prostate tumor samples were genotyped by real-time PCR with regard to the RNaseL mutation. DNA and RNA samples from these patients were screened for the presence of XMRV-specific gag sequences using a highly sensitive nested PCR and RT-PCR approach. Furthermore, 146 sera samples from prostate tumor patients were tested for XMRV Gag and Env antibodies using a newly developed ELISA assay. In agreement with earlier data, 12.9% (76 samples) were shown to be of the QQ genotype. However, XMRV specific sequences were detected at neither the DNA nor the RNA level. Consistent with this result, none of the sera analyzed from prostate cancer patients contained XMRV-specific antibodies. Conclusion Our results indicate a much lower prevalence (or even complete absence) of XMRV in prostate tumor patients in Germany. One possible reason for this could be a geographically restricted incidence of XMRV infections.

As a prelude to primate studies, the immunogenicity of wild-type and codon-optimized versions of simian immunodeficiency virus (SIV)agm Gag DNA, with and without co-administered granulocyte–macrophage colony-stimulating factor (GM-CSF) DNA, was directly compared in two strains of mice. Gag-specific T cells in the splenocytes of BALB/c and C57BL/6 mice immunized by gene gun were quantified by ELISpot using panels of overlapping synthetic peptides (15mers) spanning the entire capsid proteins of SIVagm, SIVmac and human immunodeficiency virus type 1. Specific antibodies were measured by ELISA. Codon optimization was shown to significantly increase the immune response to the DNA immunogens, reducing the amount of DNA necessary to induce cellular and antibody responses by one and two orders of magnitude, respectively. Co-administration of murine GM-CSF DNA was necessary for the induction of high level T- and B-cell responses. Finally, it was possible to identify both known and novel T-cell epitopes in the Gag proteins of the three viruses.

Orthopoxviruses code for numerous immunomodulatory proteins, the structure and function of which are clarified inadequately. Antibodies constitute a potent tool to study such proteins, enabling conclusions on protein location and time course of expression. However, common antibody production in mice or rabbits requires tedious protein expression and injection, as well as blood collection at regular intervals. To simplify this procedure, IgY antibodies specific for poxviral proteins (F1L and p28) were generated by immunisation of chickens, because antibody retrieval from eggs allows the non-invasive generation of huge amounts of antibodies. The main intentions were (i) to decrease invasiveness, (ii) to immunise with native forms of proteins and (iii) to circumvent previous protein expression and purification. Therefore, chicken were immunised with DNA expression vectors coding for conserved domains of the selected proteins delivered for the first time by a gene gun. Four weeks after initial immunisation specific antibodies were found in the egg yolk as proven by immunofluorescence staining of poxvirus-infected cells. The specific IgY titre rose to 1:80,000 and was stable for more than 120 days. With this investigation we present an universal procedure for IgY design and production that can be applied for various issues in the future.

Objective: A number of trials in primates using a wide range of putative vaccines based on simian immunodeficiency virus (SIV) have been performed and are summarised here. Methods: Rhesus macaques and African green monkey (AGMs) were immunised with the test vaccines and challenged with live virus to test the efficacy of the induced or transferred immune responses to protect from infection or disease development. Results: In initial studies, successful protection from challenge by whole inactivated virus vaccines was subsequently shown to be mediated by immune responses to human cell rather than viral proteins. Passive transfer of neutralising antibodies failed to protect against challenge. The induction of SIV-specific cytotoxic T lymphocytes (CTLs) using lipopeptides also failed to protect from infection, and whereas the frequency of post-infection CTLs (as measured by limiting dilution CTL assay and MHC/tetramer staining) correlated inversely with the cell-associated virus load, no correlation with the plasma virus load was observed. No immunological correlation of protection could be identified in macaques immunised with live attenuated SIV, with sterilising immunity being induced as early as 10 weeks after infection with the attenuated virus. Similarly, whole inactivated virus and passive IgG transfer failed to protect the natural host AGM species from challenge with apathogenic SIVagm, although live attenuated SIVagm afforded some protection despite the lack of overt vaccine virus replication. Conclusions: ‘Traditional’ types of vaccine are either ineffective or inappropriate for use in humans. Current efforts are therefore focusing on the rapidly evolving field of genetic vaccines based on vector DNA and recombinant, attenuated viral and bacterial vectors.

High-pressure discharges are generated using Micro-Structured Electrode (MSE) arrays with electrode distances between 50 and 250 µm. These arrays consist either of a planar electrode system bonded to a dielectric substrate or of a matrix of holes perforated in a composite sheet made out of two metallic foils separated by an insulator. Stable discharges were produced for pressures ranging from 10 to 1000 mbar using DC and radio frequency excitation. The optical appearance is that of a homogeneous glow discharge. Spectral investigations have revealed the presence of a large number density of metastable atoms and highly energetic electrons, while the discharge has a non-thermal character. The non-equilibrium high -pressure plasma provided by the MSE arrays is suitable for surface activation, thin film deposition and reduction of pollutants.