Single-photon-level narrowband memory in a hollow-core photonic bandgap fiber.

An experimental platform operating at the level of individual quanta and providing strong light-matter coupling is a key requirement for quantum information processing. In our work, we show that hollow-core photonic bandgap fibers filled with laser-cooled atoms might serve as such a platform, despite their typical complicated birefringence properties. To this end, we present a detailed theoretical and experimental study to identify a fiber with suitable properties to achieve operation at the single-photon level. In the fiber, we demonstrate the storage and on-demand retrieval as well as the creation of stationary light pulses, based on electromagnetically induced transparency, for weak coherent light pulses down to the single-photon level with an unconditional noise floor of 0.017(4) photons per pulse. These results clearly demonstrate the prospects of such a fiber-based platform for applications in quantum information networks.

Phase I clinical trial of mixed bacterial vaccine (Coley's toxins) in patients with NY-ESO-1 expressing cancers: immunological effects and clinical activity.

PURPOSE: Mixed bacterial vaccine (MBV, Coley's toxins) is a historical, vaguely defined preparation of heat-inactivated Streptococcus pyogenes and Serratia marcescens used as nonspecific immunotherapy in the treatment of cancer. The mechanism of action is suspected to have an immunologic basis, yet it is poorly defined up to now. We developed a new, biochemically well defined and current good manufacturing practice-compliant MBV preparation, which has been investigated in patients with NY-ESO-1 expressing cancers. EXPERIMENTAL DESIGN: Patients received MBV subcutaneously at a starting dose of 250 EU (endotoxin units) twice a week. The MBV dose was escalated in each patient until a body temperature of 38°C to 39.5°C was induced or up to the maximum dose of 547.000 EU. Changes in serum cytokine levels were determined and immune responses to NY-ESO-1 were evaluated. Tumor response was assessed according to RECIST. RESULTS: Twelve patients were enrolled and 11 of them developed fever after the administration of MBV. Ten of 12 patients showed a consistent increase in serum IL-6 levels with the highest levels coinciding with the highest body temperature. A subgroup of patients showed increasing levels of TNF-α, IFN-γ, and IL1-ß. A patient with metastatic bladder cancer showed a partial tumor response strongly correlated with MBV-induced fever and highly elevated levels of several cytokines. CONCLUSIONS: MBV at fever-inducing dose levels can lead to a massive induction of immunoregulatory cytokines that may be involved in inducing tumor regressions. We propose to further explore the role of MBV as a potent immune modulator at higher dose levels and in conjunction with antigen-specific cancer vaccines.

Therapeutic administration of a synthetic CpG oligodeoxynucleotide triggers formation of anti-CpG antibodies.

The synthetic oligodeoxynucleotide CpG 7909, which contains unmethylated cytosine/guanine (CpG) motifs, has potent immunostimulatory effects when coadministered with NY-ESO-1 peptides or recombinant NY-ESO-1 protein, resulting in an enhanced cellular and humoral immune response against the vaccine antigen. In this study, we report the development of anti-CpG-ODN antibodies in 21 of 37 patients who received CpG 7909 either alone or as a vaccine adjuvant. Specific anti-CpG immunoglobulin G (IgG) antibody titers ranged from 1:400 to 1:100,000. The anti-CpG antibodies cross-reacted with other synthetic CpG-ODNs but not with the DNA of mixed bacterial vaccine and were shown to be phosphorothioate backbone specific. Vaccine-related severe side effects observed in some patients were most likely not related to the development of anti-CpG antibodies. In addition, anti-CpG antibodies did not have negative effects on the vaccine immune response. These results show that anti-CpG antibodies develop in humans against short unmethylated CpG dinucleotide sequences after administration of CpG 7909. Our data therefore substantiate the potency of CpG 7909 to directly stimulate human B-cells and suggest that anti-CpG antibody monitoring should be a part of ongoing and planned clinical trials with CpG-ODNs.

Efficacy of vaccination with recombinant vaccinia and fowlpox vectors expressing NY-ESO-1 antigen in ovarian cancer and melanoma patients.

Recombinant poxviruses (vaccinia and fowlpox) expressing tumor-associated antigens are currently being evaluated in clinical trials as cancer vaccines to induce tumor-specific immune responses that will improve clinical outcome. To test whether a diversified prime and boost regimen targeting NY-ESO-1 will result in clinical benefit, we conducted two parallel phase II clinical trials of recombinant vaccinia-NY-ESO-1 (rV-NY-ESO-1), followed by booster vaccinations with recombinant fowlpox-NY-ESO-1 (rF-NY-ESO-1) in 25 melanoma and 22 epithelial ovarian cancer (EOC) patients with advanced disease who were at high risk for recurrence/progression. Integrated NY-ESO-1-specific antibody and CD4(+) and CD8(+) T cells were induced in a high proportion of melanoma and EOC patients. In melanoma patients, objective response rate [complete and partial response (CR+PR)] was 14%, mixed response was 5%, and disease stabilization was 52%, amounting to a clinical benefit rate (CBR) of 72% in melanoma patients. The median PFS in the melanoma patients was 9 mo (range, 0-84 mo) and the median OS was 48 mo (range, 3-106 mo). In EOC patients, the median PFS was 21 mo (95% CI, 16-29 mo), and median OS was 48 mo (CI, not estimable). CD8(+) T cells derived from vaccinated patients were shown to lyse NY-ESO-1-expressing tumor targets. These data provide preliminary evidence of clinically meaningful benefit for diversified prime and boost recombinant pox-viral-based vaccines in melanoma and ovarian cancer and support further evaluation of this approach in these patient populations.

Efficient in vivo priming by vaccination with recombinant NY-ESO-1 protein and CpG in antigen naive prostate cancer patients.

PURPOSE: NY-ESO-1, one of the most immunogenic tumor antigens, is expressed in 15% to 25% of metastatic prostate cancers. The immunological and clinical effects of vaccination with recombinant NY-ESO-1 protein combined with CpG as adjuvant were evaluated. EXPERIMENTAL DESIGN: In a phase I clinical study, patients with advanced prostate cancer were vaccinated with recombinant NY-ESO-1 protein (100 µg) mixed with CpG 7909 (2.5 mg) every 3 weeks intradermally for 4 doses. Objectives of the study were the safety of the vaccine and changes of specific humoral and cellular immunological responses to NY-ESO-1 in relation to detectable NY-ESO-1 expression in the individual tumor. RESULTS: All 12 baseline sero-negative patients developed high-titer NY-ESO-1 antibody responses. B-cell epitope mapping identified NY-ESO-1 p91-110 to be recognized most frequently by vaccine-induced antibodies. Two patients developed significant antibody titers against the adjuvant CpG. NY-ESO-1-specific CD4+ and/or CD8+ T-cell responses were induced in 9 patients (69%). Five of these 9 patients did not express NY-ESO-1 in the autologous tumor. Postvaccine CD8+ T-cell clones recognized and lyzed HLA-matched tumor cell lines in an antigen-specific manner. CONCLUSION: Our data provide clear evidence for the capacity of NY-ESO-1 protein/CpG vaccine to induce integrated antigen-specific immune responses in vivo and to efficiently prime CD8+ T-cell responses in NY-ESO-1 antigen-negative patients. Our results may also support further clinical vaccination protocols with NY-ESO-1 protein not only focused on the treatment of existing cancer, but also to prevent further development of NY-ESO-1 positive cancers in vivo.

[Long-term remission of malignant melanoma stage IV after antigen-specific immunotherapy]. / Langzeitremission bei malignem Melanom Stadium IV nach antigenspezifischer Immuntherapie.

This case report describes the clinical course of a patient with progressing metastatic melanoma (M1a) under standard chemotherapy, followed by long-term partial remission of disease under treatment with experimental, specific immunotherapy. Detectable specific immune responses demonstrate the correlation between continued tumor regression and the administered specific immunotherapy.

Tumor-reactive CD8+ T-cell responses after vaccination with NY-ESO-1 peptide, CpG 7909 and Montanide ISA-51: association with survival.

Peptide-based vaccines have led to the induction of antigen-specific CD8(+) T-cell responses in patients with NY-ESO-1 positive cancers. However, vaccine-induced T-cell responses did not generally correlate with improved survival. Therefore, we tested whether a synthetic CpG 7909 ODN (deoxycytidyl-deoxyguanosin oligodeoxy-nucleotides) mixed with NY-ESO-1 peptide p157-165 and incomplete Freund's adjuvants (Montanide(R) ISA-51) led to enhanced NY-ESO-1 antigen-specific CD8(+) immune responses in patients with NY-ESO-1 or LAGE-1 expressing tumors. Of 14 HLA-A2+ patients enrolled in the study, 5 patients withdrew prematurely because of progressive disease and 9 patients completed 1 cycle of immunization. Nine of 14 patients developed measurable and sustained antigen-specific CD8(+) T-cell responses: Four had detectable CD8+ T-cells against NY-ESO-1 after only 2 vaccinations, whereas 5 patients showed a late-onset but durable induction of NY-ESO-1 p157-165 specific T-cell response during continued vaccination after 4 months. In 6 patients, vaccine-induced antigen-specific T-cells became detectable ex vivo and reached frequencies of up to 0.16 % of all circulating CD8(+) T-cells. Postvaccine T-cell clones were shown to recognize and lyse NY-ESO-1 expressing tumor cell lines in vitro. In 6 of 9 patients developing NY-ESO-1-specific immune responses, a favorable clinical outcome with overall survival times of 43+, 42+, 42+, 39+, 36+ and 27+ months, respectively, was observed.

Whole-body hyperthermia (WBH) in combination with carboplatin in patients with recurrent ovarian cancer - a phase II study.

OBJECTIVE: Despite considerable progress in the front-line treatment in patient with advanced ovarian cancer, the outcome of patients with recurrent or refractory disease is still poor. Based on promising results of a pilot study, we initiated a phase II study with WBH and carboplatin in pretreated patients with advanced ovarian cancer to investigate the toxicity and efficacy of WBH in combination with carboplatin. METHODS: 47 patients with histologically confirmed epithelial ovarian carcinoma were enrolled in the study. Patients were pretreated with at least one palliative chemotherapy regimen. Of 47 patients 24 were classified as platinum refractory or resistant and 16 as platinum sensitive. RESULTS: Main toxicity was hematological with grade 3/4 anaemia, leukopenia and thrombocytopenia occurring in 49%, 49% and 65%, respectively. Cardiac complications occurred with grade 1/2 in 22 of 47 (47%) patients and with grade 3 in 1 patient (2%). In 35 patients evaluable for response, the overall response rate was 45% [CR: 4/35 (11%), PR: 12/35 (34%), NC: 9/35 (26%]. In platinum refractory and resistant patients we observed CR in 6%, PR in 24% and NC in 24%. The median overall survival and progression free survival were 61.5 weeks and 29 weeks, respectively. CONCLUSION: This study confirms that WBH in combination with carboplatin is an active salvage treatment option in patients with advanced ovarian cancer. However, significant hematological toxicity has to be considered and renders this regimen less suitable for palliative care setting. There is no evidence yet, that whole-body hyperthermia contributes to any clinical improvement beyond chemotherapy alone. This question can only be addressed in a randomized phase III trial.

LUD 00-009: phase 1 study of intensive course immunization with NY-ESO-1 peptides in HLA-A2 positive patients with NY-ESO-1-expressing cancer.

NY-ESO-1 is a cancer-testis antigen and an attractive target for immunotherapy in patients with different malignancies. Here we report the results of a phase I clinical study of intensive course NY-ESO-1 peptide vaccination, evaluating the safety, immunogenicity and clinical response in HLA-A2 positive patients with NY-ESO-1 expressing cancers. Of 20 patients enrolled in the trial, 14 completed at least 2 cycles of immunization and were evaluable for clinical and immunological response. Five of these evaluable patients were treated in cohort 1 (baseline seropositive) and 9 patients were treated in cohort 2 (baseline seronegative). During vaccination, NY-ESO-1-specific CD8+ T-cells were induced in 3 of 9 baseline seronegative patients. In patients with pre-existing antigen-specific CD8+ T-cells, their number increased or remained stable. In contrast to previous immunization protocols with less intensive immunization schedules, we observed a rapid induction of high magnitude NY-ESO-1 peptide-specific T-cell responses detectable already on day 15-22 of immunization. A specific immune response of high magnitude and early onset may be more effective in eliminating minimal residual disease in adjuvant treatment situations and in preventing tumor progression due to immune escape mechanisms.

The phenolic compounds in Cladonia lichens are not antimicrobial in soils.

According to classic text books on lichen biology, the phenolic secondary chemicals in lichens have antibiotic effects on soil microorganisms and mycorrhizal fungi in ecosystems. However, the experimental evidence for this under natural conditions is still relatively scarce. We examined some of the assumptions behind the concept of antimicrobial effects of lichen secondary substances: (1) the secondary substances of Cladonia stellaris, usnic and perlatolic acids, are leached out from the lichens by rainwater; (2) these substances inhibit the microbial activity of soil, and; (3) since they are extremely resistant to microbial decomposition, the soil underneath a continuous lichen mat is enriched in usnic and perlatolic acids. Our results did not support any of these assumptions. The evidence for the antimicrobial activity of lichen secondary substances seems to be weak in comparison to other suggested functions such as light filtering and herbivore protection. We suggest that it is time to re-evaluate the evidence for the antimicrobial ecological role of lichen secondary substances in natural systems.

Mitomycin C, 5-fluorouracil, leucovorin, and oxaliplatin as a salvage therapy for patients with cisplatin-resistant advanced gastric cancer: a phase I dose escalation trial.

BACKGROUND: This study aimed at evaluating the feasibility and toxicity of a salvage therapy with mitomycin C (MMC), 5-fluorouracil (5-FU), leucovorin, and oxaliplatin in patients with cisplatin-resistant advanced gastric cancer. METHODS: A 3-patient cohort dose-escalating study design was used. The patients received FLO: oxaliplatin 85 mg/m2, 5-FU 2,600 mg/m2 (24 h), leucovorin 200 mg/m2 on days 1, 15, and 29 plus MMC on day 1 (FLOM). The MMC dose was escalated from 6 to 12 mg/m2 in 2- mg/m2 steps. Cycles were repeated every 6 weeks. RESULTS: Twenty patients were enrolled in 4 treatment cohorts. The treatment was well tolerated with grade 3 or 4 nonhematological toxicities affecting less than 5% of patients. Grade 3 or 4 neutropenia, anemia, and thrombocytopenia were observed in 9 (45%), 7 (35%), and 5 (25%) of 20 patients, respectively. Mild but prolonged thrombocytopenia was dose limiting, requiring treatment discontinuation or a treatment delay >or=2 weeks in 8 (40%) of 20 patients. MMC 10 mg/m2 every 6 weeks was considered as the optimal dose in combination with FLO. Objective responses were observed in 7 (35%) of 20 patients, and 7 further patients (35%) had stable disease. Median time to progression and overall survival were 4.1 and 8 months, respectively. CONCLUSIONS: Prolonged cumulative myelotoxicity was dose limiting in the therapy with MMC, 5-FU, and oxaliplatin. This combination chemotherapy seems to overcome cisplatin resistance in patients with advanced gastric cancer.

Recombinant vaccinia/fowlpox NY-ESO-1 vaccines induce both humoral and cellular NY-ESO-1-specific immune responses in cancer patients.

NY-ESO-1 is a cancer/testis antigen expressed in a range of human malignancies, and a number of vaccine strategies targeting NY-ESO-1 are being developed. In the present study, the safety and immunogenicity of recombinant vaccinia-NY-ESO-1 and recombinant fowlpox-NY-ESO-1 were analyzed in a series of 36 patients with a range of different tumor types. Each construct was first tested individually at two different dose levels and then in a prime-boost setting with recombinant vaccinia-NY-ESO-1 followed by recombinant fowlpox-NY-ESO-1. The vaccines were well tolerated either individually or together. NY-ESO-1-specific antibody responses and/or specific CD8 and CD4 T cell responses directed against a broad range of NY-ESO-1 epitopes were induced by a course of at least four vaccinations at monthly intervals in a high proportion of patients. CD8 T cell clones derived from five vaccinated patients were shown to lyse NY-ESO-1-expressing melanoma target cells. In several patients with melanoma, there was a strong impression that the natural course of the disease was favorably influenced by vaccination.

Phase I clinical study of the recombinant antibody toxin scFv(FRP5)-ETA specific for the ErbB2/HER2 receptor in patients with advanced solid malignomas.

INTRODUCTION: ScFv(FRP5)-ETA is a recombinant antibody toxin with binding specificity for ErbB2 (HER2). It consists of an N-terminal single-chain antibody fragment (scFv), genetically linked to truncated Pseudomonas exotoxin A (ETA). Potent antitumoral activity of scFv(FRP5)-ETA against ErbB2-overexpressing tumor cells was previously demonstrated in vitro and in animal models. Here we report the first systemic application of scFv(FRP5)-ETA in human cancer patients. METHODS: We have performed a phase I dose-finding study, with the objective to assess the maximum tolerated dose and the dose-limiting toxicity of intravenously injected scFv(FRP5)-ETA. Eighteen patients suffering from ErbB2-expressing metastatic breast cancers, prostate cancers, head and neck cancer, non small cell lung cancer, or transitional cell carcinoma were treated. Dose levels of 2, 4, 10, 12.5, and 20 microg/kg scFv(FRP5)-ETA were administered as five daily infusions each for two consecutive weeks. RESULTS: No hematologic, renal, and/or cardiovascular toxicities were noted in any of the patients treated. However, transient elevation of liver enzymes was observed, and considered dose limiting, in one of six patients at the maximum tolerated dose of 12.5 microg/kg, and in two of three patients at 20 microg/kg. Fifteen minutes after injection, peak concentrations of more than 100 ng/ml scFv(FRP5)-ETA were obtained at a dose of 10 microg/kg, indicating that predicted therapeutic levels of the recombinant protein can be applied without inducing toxic side effects. Induction of antibodies against scFv(FRP5)-ETA was observed 8 days after initiation of therapy in 13 patients investigated, but only in five of these patients could neutralizing activity be detected. Two patients showed stable disease and in three patients clinical signs of activity in terms of signs and symptoms were observed (all treated at doses > or = 10 microg/kg). Disease progression occurred in 11 of the patients. CONCLUSION: Our results demonstrate that systemic therapy with scFv(FRP5)-ETA can be safely administered up to a maximum tolerated dose of 12.5 microg/kg in patients with ErbB2-expressing tumors, justifying further clinical development.

Intratumoral T-cell infiltrates and MHC class I expression in patients with stage IV melanoma.

The infiltration of tumors by T cells has been shown to correlate with prolonged patients' survival. However, it remains unclear why only some tumors are infiltrated with T cells. This study was designed to investigate possible correlations between intratumoral T-cell infiltrates and the expression of cancer-associated antigens and MHC class I and II molecules in patients with melanoma. Fresh frozen samples from 124 stage IV melanoma patients were analyzed by immunohistochemistry for the expression of Melan-A/MART-1, tyrosinase, gp100, NY-ESO-1, and MHC class I and II. Intratumoral T-cell and B-cell infiltrates were detected by staining with anti-CD4, anti-CD8, anti-CD3, and L26 antibodies. The NY-ESO-1 serum antibody status was assessed by Western blot analysis. Intratumoral CD8+ and CD4+ T cells were detected in 63.9% and 71.3% of patients, respectively. We observed a significant heterogeneity of the expression of the melanocyte differentiation antigens, NY-ESO-1, and MHC class I and II molecules. The only significant correlation was found between the expression of MHC class I and the presence of CD4+ and CD8+ T cells (P < 0.0001). There was a strong association between these two variables with respect to the density and distribution of infiltrating T cells and the pattern of MHC class I expression (focal versus homogenous). Intratumoral T-cell infiltration is closely correlated with the MHC class I expression but not with the expression of differentiation antigens, cancer-associated antigens, or MHC class II molecules. These results may have implications for the definition of prognostic variables and for the identification of patients who may benefit from antigen-specific cancer immunotherapy.

Two phase I studies of low dose recombinant human IL-12 with Melan-A and influenza peptides in subjects with advanced malignant melanoma.

Preclinical studies have shown that low dose IL-12 can potentiate cytotoxic lymphocyte responses. Since previous trials have demonstrated significant toxicity from high dose recombinant human IL-12 (rhIL-12), we sought to determine an optimal biological dose for rhIL-12 at lower doses when combined with peptide antigens. Two studies were undertaken. The rhIL-12 was administered at doses of 0 (placebo), 10, 30 and 100 ng/kg, subcutaneously in one study and intravenously in the other. Apart from IL-12 dosing, the studies were identical. Subjects had evaluable stage III or IV melanoma which expressed Melan-A by RT-PCR or immunohistochemistry. Melan-A (26-35) (EAAGIGILTV) and influenza matrix (58-66) (GILGFVFTL) peptides were administered intradermally on weeks 1, 2, 3, 4 and 9. Twenty-eight subjects were enrolled, of whom 24 were evaluable for clinical and immunological responses. Therapy was well tolerated, the main adverse event being influenza-like symptoms. Immunological monitoring included the evaluation of cutaneous reactions and assays for antigen-specific T-cells. Clinical responses included a complete response in a subject with small volume subcutaneous disease, a partial response in a subject with hepatic metastases, and mixed responses in pulmonary, pleural and nodal disease. Biopsies of accessible tumors showed infiltration with CD4+ and CD8+ lymphocytes capable of lysing Melan-A peptide-pulsed targets in vitro. No clear dose-dependent effect of rhIL-12 could be determined. The rhIL-12 given either s.c. or i.v. was well tolerated at doses of 10-100 ng/kg. Clinical and immunological activity has been observed in this study where peptides were administered either with or without low dose rhIL-12.