18 research outputs found
Substantially increased sensitivity of the spot-ELISA for the detection of anti-insulin antibody-secreting cells using a capture antibody and enzyme-conjugated insulin
This paper describes an antibody capture spot-ELISA for the detection of anti-insulin antibody-secreting cells. The assay is based on the binding of secreted antibodies by immobilised isotype-specific capture antibodies and subsequent detection of insulin-specific antibodies with a conjugate of human insulin and alkaline phosphatase (HI-AP). Compared with the conventional approach, using antigen for coating and employing an enzyme-linked detecting antibody, this technique improved the detection of murine cells secreting anti-insulin antibodies of different IgG subclasses
Antigen detection in vivo after immunization with different presentation forms of rabies virus antigen, II. Cellular but not humoral systemic immune responses against rabies virus immune stimulating complexes are macrophage dependent
In this paper we describe the effect of depletion of splenic macrophages on the uptake, and immune response against, different formulations of rabies virus antigen. Splenic macrophages were removed by intravenous injection with clodronate liposomes. beta-propiolacton inactivated rabies virus (RV-BPL) and immune-stimulating complexes (iscom) containing these antigens were given to macrophage-depleted and control mice. In the absence of phagocytic cells in the spleen, antigen is still trapped in the red pulp and to a lesser extent in the peri-arteriolar lymphocyte sheaths (PALS) for both antigen formulations. The localization pattern in the main area of immune response induction, namely the follicles, was unaltered after macrophage depletion. Functionally, the depletion of splenic and liver macrophages had no influence on the induction of specific antibody responses in both RV-BPL or RV-iscom immunized mice, even though the latter presentation form was clearly associated with specific localization in the marginal metallophillic macrophages. In RV-BPL immunized mice, macrophage depletion had no influence on proliferative T-cell responses. However, macrophage-depleted mice that were immunized with RV-iscom showed a significant decrease in proliferative T-cell respon
Leveraging academic knowledge in the innovation ecosystem
Scientific advancement and advancements in information technology have
increased our capability for sharing information, and spreading scientific
discoveries throughout society. In the past decade the Dutch government has
been trying to stimulate the knowledge economy through various means. Among
them the stimulation of the founding of the Dutch Centres for Entrepreneurship,
and the Valorisation programme. However, over the years, publication volume
has become the main indicator for being a successful scientist. This focus on
publications and research disincentivizes scientists from activities that generate
more concrete value for society.
The Societal Impact Value Cycle seeks to offer scientists and others a toolbox
for visualising and understanding the way innovation can be fostered, and how
other processes can foster scientific research in return. It also maps the way by
which an innovation ecosystem generates socio-economic value from academic
activities. It should be noted that not all scientific research leads to innovations
that generate value for society, and not all research is intended to change the
course of events. Nonetheless, fostering cooperation between research institutes
and societal stakeholders, and increasing awareness of how entrepreneurial
skills and activities could not only lead to a return on investments necessary for
scientific advancement, but also increase the societal impact from academic
endeavours. This could benefit our society, and societies worldwide, both socially
and economically.
This publication will offer valuable insight and an effective toolbox for people
interested in socio-economic value creation from scientific research, or, in other
words, valorisation. Therewith, it lays at the heart of Stichting Maatschappij en
Onderneming’s daily occupations and our close cooperation with the Erasmus
University Rotterdam
Food-pharma convergence in medical nutrition
At present, industries within the health and life science sector are moving towards one another resulting in new industries such as the medical nutrition industry. Medical nutrition products are specific nutritional compositions for intervention in disease progression and symptom alleviation. Industry convergence, described as the blurring of boundaries between industries, plays a crucial role in the shaping of new markets and industries. Assuming that the medical nutrition industry has emerged from the convergence between the food and pharma industries, it is crucial to research how and which distinct industry domains have contributed to establish this relatively new industry. The first two stages of industry convergence (knowledge diffusion and consolidation) are measured by means of patent analysis. First, the extent of knowledge diffusion within the medical nutrition industry is graphed in a patent citation interrelations network. Subsequently the consolidation based on technological convergence
Risk in Vaccine Research and Development Quantified
To date, vaccination is the most cost-effective strategy to combat infectious diseases. Recently, a productivity gap affects the pharmaceutical industry. The productivity gap describes the situation whereby the invested resources within an industry do not match the expected product turn-over. While risk profiles (combining research and development timelines and transition rates) have been published for new chemical entities (NCE), little is documented on vaccine development. The objective is to calculate risk profiles for vaccines targeting human infectious diseases. A database was actively compiled to include all vaccine projects in development from 1998 to 2009 in the pre-clinical development phase, clinical trials phase I, II and III up to Market Registration. The average vaccine, taken from the preclinical phase, requires a development timeline of 10.71 years and has a market entry probability of 6%. Stratification by disease area reveals pandemic influenza vaccine targets as lucrative. Furthermore, vaccines targeting acute infectious diseases and prophylactic vaccines have shown to have a lower risk profile when compared to vaccines targeting chronic infections and therapeutic applications. In conclusion; these statistics apply to vaccines targeting human infectious diseases. Vaccines targeting cancer, allergy and autoimmune diseases require further analysis. Additionally, this paper does not address orphan vaccines targeting unmet medical needs, whether projects are in-licensed or self-originated and firm size and experience. Therefore, it remains to be investigated how these - and other - variables influence the vaccine risk profile. Although we find huge differences
Probiotic and synbiotic safety in infants under two years of age
In this study, we systematically evaluated safety aspects in clinical trials with probiotics and synbiotics in young infants (0-2 years of age). This study is an update of earlier reports and covers the recent literature from 2008-2013. The safety evaluation is performed along the Common Terminology Clinical Adverse Events (CTCAE) version 4.0 scale, hereby also providing guidance for future studies. Safety aspects are represented and related to number of participants per probiotic strain/culture, study duration, dosage, clinical condition and selected afflictions. The results show a deficiency in the precise reporting and classification of adverse events in most studies. Analysis of 57 clinical trials with probiotics and synbiotics in combination with eight follow-up studies indicate that probiotic administration to infants between 0 and 24 months is safe with regard to the evaluated strains in infants with a particular health status or susceptibility. Most adverse events and serious adverse events were considered unrelated to the study product, and there were no major safety concerns. Almost all studies concluded that none of the adverse effects were related to the study product; the study products are generally well tolerated. Finally, inconsistent, imprecise and potentially incomplete reporting as well as the variation in probiotic strains, dosages, administration regimes, study populations and reported outcomes, greatly limit the generalizability of conclusions and argue convincingly for obligatory and standardised behaviour on adverse events (CTCAE) reporting in 'food' studies
Growth phase of orally administered Lactobacillus strains differentially affects IgG1/IgG2a ratio for soluble antigens: Implications for vaccine development
Lactobacillus strains with probiotic activity are major constituents of numerous common food products. Due to their 'generally regarded as safe'-status (GRAS-status), Lactobacillus strains can also be genetically engineered for use in oral immunotherapeutic applications, such as vaccination and T lymphocyte tolerance induction in autoimmune disease. In the current study, we demonstrate that the growth phase of orally administered individual Lactobacillus strains can differentially affect antigen-specific antibody subclasses IgG1 and IgG2a, which might reflect skewing of systemic activity of T helper cell type 2 (Th2) and T helper cell type 1 (Th1) pathways, respectively. Mice were orally fed different wild type Lactobacillus strains in log phase or stationary phase and immunized intraperitoneally with a T-cell dependent protein antigen. Sera were evaluated for the ratio of antigen-specific IgG1 and IgG2a antibodies. Stationary Lactobacillus murines and Lactobacillus casei cultures, but not two other Lactobacillus strains, evoked significantly higher IgG1/IgG2a ratios than log phase cultures, possibly relating to increased activity of the Th2-pathway. Despite normal variation in antibody responses against TNP-CGG among individual mice, a high correlation was found between the IgG1 and IgG2a responses of mice within experimental groups. This differential antibody response is likely due to growth phase-dependent differences in bacterial cell composition. Since Lactobacillus growth phase dependent skewing of antibody responses possibly reflecting T-cell pathways can inadvertently affect allergic and (auto)-immune responses, the current findings strongly caution against unidimensional views on the oral administration of individual Lactobacillus strains for probiotic or immunotherapeutic purposes, but also suggest additional possibilities for immune modulation
Safety of probiotics and synbiotics in children under 18 years of age
This study aimed to systematically evaluate safety of probiotics and synbiotics in children ageing 0-18 years. This study is the third and final part in a safety trilogy and an update is provided using the most recent available clinical data (2008-2013) by means of the Common Terminology Clinical Adverse Events (CTCAE version 4.0) classification. Safety aspects are represented and related to number of participants per probiotic strain/culture, study duration, dosage, clinical condition and selected afflictions. Analysis of 74 clinical studies indicated that probiotic and/or synbiotic administration in children is safe with regard to the specific evaluated strains, dosages and duration. The population of children include healthy, immune compromised and obese subjects, as well as subjects with intestinal disorders, infections and inflammatory disorders. This study revealed no major safety concerns, as the adverse events (AEs) were unrelated, or not suspected to be related, to the probiotic or synbiotic product. In general the study products were well tolerated. Overall, AEs occurred more frequent in the control arm compared to children receiving probiotics and/or synbiotics. Furthermore, the results indicate inadequate reporting and classification of AEs in the majority of the studies. In addition, generalizability of conclusions are greatly limited by the inconsistent, imprecise and potentially incomplete reporting as well as the variation in probiotic strains, dosages, administration regimes, study populations and reported outcomes
CD40-CD40 ligand interactions in experimental allergic encephalomyelitis and multiple sclerosis
We investigated the role of CD40-CD40 ligand (CD40L) interactions in multiple sclerosis (MS) and experimental allergic encephalomyelitis (EAE). Activated helper T cells expressing CD40L (gp39) surface protein were found in MS patient brain sections, but not in brain tissue sections of normal controls or patients with other neurological diseases. CD40L-positive cells were co-localized with CD40-bearing cells in active lesions (perivascular infiltrates). Most of these CD40 bearing cells proved to be of the monocytic lineage (macrophages or microglial cells), and relatively few were B cells. To functionally evaluate CD40-CD40L interactions, EAE was elicited in mice by means of proteolipid-peptide immunization. Treatment with anti-CD40L monoclonal antibody completely prevented the development of disease. Furthermore, administration of anti-CD40L monoclonal antibody, even after disease onset, shortly before maximum disability score was reached led to dramatic disease reduction. The presence of helper T cells expressing CD40L in brain tissue of MS patients and EAE animals, together with the functional evidence provided by successful experimental prevention and therapy in an animal model, indicates that blockade of CD40-CD40L-mediated cellular interactions may be a method for interference in active MS
Reduced experimental autoimmune encephalomyelitis after intranasal and oral administration of recombinant lactobacilli expressing myelin antigen
Oral administration of autoantigens is a safe and convenient way to induce peripheral T-cell tolerance in autoimmune diseases like multiple sclerosis (MS). To increase the efficacy of oral tolerance induction and obviate the need for large-scale purification of human myelin proteins, we use genetically modified lactobacilli expressing myelin antigens. A panel of recombinant lactobacilli was constructed producing myelin proteins and peptides, including human and guinea pig myelin basic protein (MBP) and proteolipid protein peptide 139-151 (PLP139-151). In this study we examined whether these Lactobacillus recombinants are able to induce oral and intranasal tolerance in an animal model for multiple sclerosis, experimental autoimmune encephalomyelitis (EAE). Lewis rats received soluble cell extracts of Lactobacillus transformants intranasally three times prior to induction of EAE. For the induction of oral tolerance, rats were fed live transformed lactobacilli for 20 days. Ten days after the first oral administration EAE was induced. Intranasal administration of extracts containing guinea pig MBP (gpMBP) or MBP72-85 significantly inhibited EAE in Lewis rats. Extracts of control transformants did not reduce EAE. Live lactobacilli expressing guinea pig MBP72-85 fused to the marker enzyme β-glucuronidase (β-gluc) were also able to significantly reduce disease when administered orally. In conclusion, these experiments provide proof of principle that lactobacilli expressing myelin antigens reduce EAE after mucosal (intranasal and oral) administration. This novel method of mucosal tolerance induction by mucosal administration of recombinant lactobacilli expressing relevant autoantigens could find applications in autoimmune disease in general, such as multiple sclerosis, rheumatoid arthritis and uveitis