Heimo Lagler

Sterile protection against human malaria by chemoattenuated PfSPZ vaccine

A highly protective malaria vaccine would greatly facilitate the prevention and elimination of malaria and containment of drug-resistant parasites. A high level (more than 90%) of protection against malaria in humans has previously been achieved only by immunization with radiation-attenuated Plasmodium falciparum (Pf) sporozoites (PfSPZ) inoculated by mosquitoes; by intravenous injection of aseptic, purified, radiation-attenuated, cryopreserved PfSPZ (‘PfSPZ Vaccine’); or by infectious PfSPZ inoculated by mosquitoes to volunteers taking chloroquine or mefloquine (chemoprophylaxis with sporozoites). We assessed immunization by direct venous inoculation of aseptic, purified, cryopreserved, non-irradiated PfSPZ (‘PfSPZ Challenge’) to malaria-naive, healthy adult volunteers taking chloroquine for antimalarial chemoprophylaxis (vaccine approach denoted as PfSPZ-CVac). Three doses of 5.12 × 104 PfSPZ of PfSPZ Challenge at 28-day intervals were well tolerated and safe, and prevented infection in 9 out of 9 (100%) volunteers who underwent controlled human malaria infection ten weeks after the last dose (group III). Protective efficacy was dependent on dose and regimen. Immunization with 3.2 × 103 (group I) or 1.28 × 104 (group II) PfSPZ protected 3 out of 9 (33%) or 6 out of 9 (67%) volunteers, respectively. Three doses of 5.12 × 104 PfSPZ at five-day intervals protected 5 out of 8 (63%) volunteers. The frequency of Pf-specific polyfunctional CD4 memory T cells was associated with protection. On a 7,455 peptide Pf proteome array, immune sera from at least 5 out of 9 group III vaccinees recognized each of 22 proteins. PfSPZ-CVac is a highly efficacious vaccine candidate; when we are able to optimize the immunization regimen (dose, interval between doses, and drug partner), this vaccine could be used for combination mass drug administration and a mass vaccination program approach to eliminate malaria from geographically defined areas.

TREM-1 Activation Alters the Dynamics of Pulmonary IRAK-M Expression In Vivo and Improves Host Defense during Pneumococcal Pneumonia

Triggering receptor expressed on myeloid cells-1 (TREM-1) is an amplifier of TLR-mediated inflammation during bacterial infections. Thus far, TREM-1 is primarily associated with unwanted signs of overwhelming inflammation, rendering it an attractive target for conditions such as sepsis. Respiratory tract infections are the leading cause of sepsis, but the biological role of TREM-1 therein is poorly understood. To determine the function of TREM-1 in pneumococcal pneumonia, we first established TREM-1 up-regulation in infected lungs and human plasma together with augmented alveolar macrophage responsiveness toward Streptococcus pneumoniae. Mice treated with an agonistic TREM-1 Ab and infected with S. pneumoniae exhibited an enhanced early induction of the inflammatory response that was indirectly associated with lower levels of negative regulators of TLR signaling in lung tissue in vivo. Later in infection, TREM-1 engagement altered S. pneumoniae-induced IRAK-M (IL-1R-associated kinase-M) kinetics so as to promote the resolution of pneumonia and remarkably led to an accelerated elimination of bacteria and consequently improved survival. These data show that TREM-1 exerts a protective role in the innate immune response to a common bacterial infection and suggest that caution should be exerted in modulating TREM-1 activity during certain clinically relevant bacterial infections.

Anakinra in two adolescent female patients suffering from colchicine-resistant familial Mediterranean fever: effective but risky.

Sir, Mutations in the pyrin gene (MEFV) cause the inflammatory disorder familial Mediterranean fever (FMF) [1]. Most of the patients are treated with colchicine for the prevention of both attacks and secondary amyloidosis. Clinical failure of colchicine treatment is seen in 5 to 10% of patients. Patients who are non-responders suffer a lot despite taking painkillers. Quite often patients are unable to manage daily life because of the disease. No treatment recommendations exist for these cases [2]. Recently, two case reports concerning treatment of colchicine-resistant FMF patients with anakinra were published [3,4]. Anakinra is an interleukin-1 (Il-1) receptor antagonist. Il-1 is a major proinflammatory cytokine that is increased in activity by pyrin, which is shown to be elevated in FMF [5,6]. Since knowledge about the efficacy and tolerance of anakinra is rare we herein present two case studies of patients treated with it. Case 1: A 29-year old Turkish woman with positive personal and family FMF history was visiting our outpatient clinic in March 2007 because of recurrent FMF attacks associated with severe abdominal pain and fever. FMF was previously diagnosed in this patient in Turkey when she was 13 years of age. She had been taking colchicine tablets for several years but in the last year the attack rate had increased and she had typical symptoms every week. During the onset of symptoms she took a large amount of different painkillers, which had no effect. Despite an increased dosage of colchicine (1·5 mg d –1 ), she had elevated inflammation signs [C-reactive protein (CRP): 90·5 mg L –1 , normal: 0–10 mg L –1 ; serum amyloid A (SAA): 626 mg L –1 , normal: < 5 mg L –1 ]. Her serum creatinine level was 0·71 mg dL –1 and no proteinuria was detected. Because of her poor quality of life caused by the recurrent attacks we decided to try anakinra treatment. After informing the patient about the potential side effects and the empirical aspects of the therapy, treatment was started with 100 mg anakinra administered subcutaneously every day. Before administration a quantiFERON-TB Gold test was performed which showed a negative result. After eight days of anakinra treatment the patient was symptom free and after three weeks the inflammatory parameters almost normalised (Fig. 1). The administration of colchicine was not interrupted at any time point. Three weeks after the start of treatment, administration of anakinra was stopped because the patient was feeling well and it was assumed that continuing with colchicine would prolong the attack rate. After 4 days the patient came to our outpatient department again and was complaining of severe abdominal pain. The inflammation parameters were also elevated. Administration of anakrina was restarted and recovery was achieved within a few days concomitant with a decrease in the inflammation parameters. Colchicine was stopped at this time point since efficacy was missing. During the following 3 months an ‘on and off treatment’ with anakrina took place. The first time the application was stopped because the patient could not tolerate any further injections due to severe pain at the site of the injection. Her symptoms and inflammation parameters returned very quickly afterwards. The patient then decided to restart anakinra because the severity of her pain due to FMF persistently increased. Since the patient’s insurance company refused to pay for this treatment, anakinra therapy was stopped until this problem was resolved. Vienna General Hospital, Medical University of Vienna, Vienna, Austria (R. Gattringer, H. Lagler, K. B. Gattringer, S. Knapp, H. Burgmann, S. Winkler, W. Graninger, F. Thalhammer).

Daptomycin, Fosfomycin, or Both for Treatment of Methicillin-Resistant Staphylococcus aureus Osteomyelitis in an Experimental Rat Model

ABSTRACT The in vivo activities of daptomycin, fosfomycin, and a combination of both antibiotics against a clinical isolate of methicillin-resistant Staphylococcus aureus (daptomycin MIC, 0.25 μg/ml; fosfomycin MIC, 0.5 μg/ml) were evaluated in a rat model of osteomyelitis. A total of 37 rats with experimental osteomyelitis were treated for 4 weeks with either 60 mg/kg of body weight of daptomycin subcutaneously once daily, 75 mg/kg fosfomycin intraperitoneally once daily, a combination of both drugs, or a saline placebo. After the completion of treatment, animals were euthanized, and the infected tibiae were processed for quantitative bacterial culture. Bone cultures were found to be positive for methicillin-resistant S. aureus in 9 of 9 (100%) animals of the placebo group, in 9 of 9 (100%) animals treated with daptomycin, in 1 of 10 (10%) fosfomycin-treated rats, and in 1 of 9 (22.2%) rats comprising the combination group. Results of bacterial counts in the bone samples were expressed as log10 CFU/g of bone and analyzed by using the Mann-Whitney U test followed by Bonferronis multiple-comparison test. Based on bacterial counts, treatment with daptomycin was significantly superior to placebo, although it remained inferior to treatment with fosfomycin. No synergistic or antagonistic effect was observed for the combination therapy. No development of resistance against daptomycin or fosfomycin was observed after the 4-week treatment period.

Pandemic influenza A H1N1 vaccine in recipients of solid organ transplants: immunogenicity and tolerability outcomes after vero cell derived, non-adjuvanted, whole-virion vaccination.

During the 2009/10 pandemic of influenza A (H1N1), the American Society of Transplantation and other health organizations recommended that immunocompromised patients should be vaccinated as the key preventive measure. Since there are no data available for the immunogenicity of the unadjuvanted pandemic influenza vaccine in immunocompromised patients - as opposed to the adjuvanted preparation - the objective of this study was to evaluate the immunogenicity of an adjuvant-free H1N1 vaccine in recipients of solid organ transplants. Patients were recruited at the Vienna General Hospital, Austria. The vaccination schedule consisted of 2 doses of a whole-virion, vero cell derived, inactivated, non-adjuvanted influenza A/California/07/2009 (H1N1) vaccine given with an interval of 3 weeks. A hemagglutination inhibition (HI) assay on blood samples obtained prior to the first and after each vaccination was used for serologic analysis. The primary immunologic endpoint was the seroconversion rate, defined as the proportion of subjects with an individual 4-fold increase in HI titer of at least 1:40. In addition, virus-specific IgG antibodies to the pandemic H1N1 strain were measured using a commercially available ELISA. Twenty-five organ transplant patients (16 males, 9 females) aged 25-79 years were vaccinated and provided blood samples for serologic analysis. The time elapsed since transplantation was 10 months to 25 years (mean: 9 years; 95% CI 6-13 years). The vaccine was well tolerated and no local adverse events were noticed. After two vaccinations 37% of the patients demonstrated seroconversion in the HI assay as defined above and 70% had virus-specific IgG antibodies. Among the HI vaccine responders were 6 of 14 heart transplant recipients and 1 of 4 liver transplant recipients. The number and type of immunosuppressive agents did not significantly differ in their effect on the immune response. Our results show that the novel vero cell derived and adjuvant-free pandemic A/California/07/2009 (H1N1) influenza vaccine induced limited but measurable immune responses in adult recipients of solid organ transplants.

Cytokine profile of Plasmodium falciparum -specific T cells in non-immune malaria patients

CD3+ T cells are important sources of both pro‐ and anti‐inflammatory cytokines during Plasmodium falciparum malaria. We studied the frequency of interleukin‐2 (IL‐2), gamma interferon (IFN‐γ), tumour necrosis factor‐alpha (TNF‐α) and IL‐10 expressing CD3+ cells in 10 non‐immune malaria patients with uncomplicated malaria and in one patient with cerebral malaria after P. falciparum‐specific and non‐specific mitogenic stimulation. Analysis by fluorescence‐activated cell sorting was performed after drug‐induced clearance of parasites to allow previously sequestered T cells to be detected in peripheral blood. CD3+ cells of patients responded to P. falciparum infected erythrocytes with significant increases in the percentage of IL‐2, IFN‐γ, and TNF‐α, but also IL‐10, positive cells. CD3+ cells from malaria‐naïve donors were also responsive to specific stimulation albeit to a much lesser extent. Mitogenic stimulation of PBMC revealed no significant differences between cells of patients and controls. CD3+ cells of the patient with cerebral malaria were hyporesponsive both to the infecting parasite isolate as well as to our laboratory‐adapted P. falciparum isolate, whereas two patients with uncomplicated disease were more responsive to their infecting parasites than to the laboratory‐adapted isolate. The results indicate that the increased responsiveness of in vivo primed compared to malaria‐naïve CD3+ cells is Plasmodium‐specific and biased towards production of IFN‐γ and TNF‐α.

Hepatitis E virus seroprevalence in Austrian adults: a nationwide cross-sectional study among civilians and military professionals.

Background Hepatitis E Virus (HEV) infection is globally increasing. The present study was performed to investigate the HEV seroprevalence, exposure risks as well as occupational risks for military personnel in Austria, a Central European country. Methods and Findings A nationwide cross-sectional seroprevalence study was performed in 997 healthy Austrian adults, professional soldiers and civilians. Routine laboratory and HEV specific antibodies were determined. In addition, epidemiological information on possible risk factors for exposure to HEV was obtained. The overall seropositivity for HEV antibodies was 14.3% and significantly increased with age. Seroprevalence was significantly higher among individuals with previous military employments abroad (21.4% vs. 9.9%) and among professional soldiers aged 30–39 years (20.2% vs. 7.3%). No association was found for private travel, occupational or private animal contact or regular outdoor activities. Individuals who tested positive for antibodies against HEV had significantly higher laboratory values regarding liver enzymes, lipid levels and blood fasting glucose. Conclusions Exposure to HEV is common in Austria. Military employment abroad could be a potential risk factor for HEV infection. Further studies are required to investigate the significance of pathological laboratory results found among asymptomatic individuals previously exposed to HEV.

Clinical Features, Treatment and Outcome of Mucosa-Associated Lymphoid Tissue (MALT) Lymphoma of the Ocular Adnexa: Single Center Experience of 60 Patients

Background Orbital marginal zone B-cell lymphoma (OAML) constitutes for the most frequent diagnosis in orbital lymphoma. Relatively little data, however, have been reported in larger cohorts of patients staged in a uniform way and no therapy standard exists to date. Material and Methods We have retrospectively analyzed 60 patients diagnosed and treated at our institution 1999–2012. Median age at diagnosis was 64 years (IQR 51–75) and follow-up time 43 months (IQR 16–92). All patients had undergone uniform extensive staging and histological diagnosis was made by a reference pathologist according to the WHO classification. Results The majority of patients presented with stage IE (n = 40/60, 67%), three had IIE/IIIE and the remaining 17 stage IVE. Seven patients with IVE had bilateral orbital disease whereas the others showed involvement of further organs. Treatment data were available in 58 patients. Local treatment with radiotherapy (14/58, 24%) or surgery (3/58, 5%) resulted in response in 82% of patients. A total of 26 patients (45%) received systemic treatment with a response rate of 85%. Nine patients received antibiotics as initial therapy; response rate was 38%. Watchful-waiting was the initial approach in 6/58 patients. In total 28/58 patients (48%) progressed and were given further therapy. Median time-to-progression in this cohort was 20 months (IQR 9–39). There was no difference in time-to-progression after first-line therapy between the different therapy arms (p = 0.14). Elevated beta-2-microglobulin, plasmacytic differentiation, autoimmune disorder and site of lymphoma were not associated with a higher risk for progress. Conclusion Our data underscore the excellent prognosis of OAML irrespective of initial therapy, as there was no significant difference in time-to-progression and response between local or systemic therapy. In the absence of randomized trials, the least toxic individual approach should be chosen for OAML.

Immunogenicity and Tolerability after Two Doses of Non-Adjuvanted, Whole-Virion Pandemic Influenza A (H1N1) Vaccine in HIV-Infected Individuals

Background During the influenza pandemic of 2009/10, the whole-virion, Vero-cell-derived, inactivated, pandemic influenza A (H1N1) vaccine Celvapan® (Baxter) was used in Austria. Celvapan® is adjuvant-free and was the only such vaccine at that time in Europe. The objective of this observational, non-interventional, prospective single-center study was to evaluate the immunogenicity and tolerability of two intramuscular doses of this novel vaccine in HIV-positive individuals. Methods and Findings A standard hemagglutination inhibition (HAI) assay was used for evaluation of the seroconversion rate and seroprotection against the pandemic H1N1 strain. In addition, H1N1-specific IgG antibodies were measured using a recently developed ELISA and compared with the HAI results. Tolerability of vaccination was evaluated up to one month after the second dose. A total of 79 HIV-infected adults with an indication for H1N1 vaccination were evaluated. At baseline, 55 of the 79 participants had an HAI titer ≥1∶40 and two patients showed a positive IgG ELISA. The seroconversion rate was 31% after the first vaccination, increasing to 41% after the second; the corresponding seroprotection rates were 92% and 83% respectively. ELISA IgG levels were positive in 25% after the first vaccination and in 37% after the second. Among the participants with baseline HAI titers <1∶40, 63% seroconverted. Young age was clearly associated with lower HAI titers at baseline and with higher seroconversion rates, whereas none of the seven patients >60 years of age had a baseline HAI titer <1∶40 or seroconverted after vaccination. The vaccine was well tolerated. Conclusion The non-adjuvanted pandemic influenza A (H1N1) vaccine was well tolerated and induced a measurable immune response in a sample of HIV-infected individuals.

Single- and Repeated-Dose Pharmacokinetics of Ceftaroline in Plasma and Soft Tissues of Healthy Volunteers for Two Different Dosing Regimens of Ceftaroline Fosamil

ABSTRACT Ceftaroline fosamil (CPT-F) is currently approved for use for the treatment of complicated skin and soft tissue infections and community-acquired pneumonia at 600 mg twice daily (q12h), but other dosing regimens are under evaluation. To date, very limited data on the soft tissue pharmacokinetics (PK) of the active compound, ceftaroline (CPT), are available. CPT concentrations in the plasma, muscle, and subcutis of 12 male healthy volunteers were measured by microdialysis after single and repeated intravenous administration of 600 mg CPT-F q12h or three times daily (q8h) in two groups of 6 subjects each. Relevant PK and PK/pharmacodynamic (PD) parameters were calculated and compared between groups. In plasma, the area under the concentration-time curve (AUC) from 0 to 24 h for total CPT and the cumulative percentage of the dosing interval during which the free drug concentrations exceeded the MIC (fTMIC) for unbound CPT for the currently established threshold of 1 mg/liter were significantly higher in the group receiving CPT-F q8h. Exposure to free drug in soft tissues was higher in the group receiving CPT-F q8h, but high interindividual variability in relevant PK parameters was observed. The mean ratios of the AUC from time zero to the end of the dosing interval (AUC0-τ) for free CPT in soft tissues and the AUC0-τ for the calculated free fraction in plasma at steady state ranged from 0.66 to 0.75. Administration of CPT-F q8h led to higher levels of drug exposure in all investigated compartments. When MIC values above 1 mg/liter were assumed, the calculated fTMIC after dosing q12h was markedly lower than that after dosing q8h. The clinical implications of these differences are discussed in light of recently completed clinical phase III and PK/PD studies.