Dear Madam or Sir,
As in previous years, DIARECT will be exhibiting at MEDICA 2016, the world’s largest medical trade show that will take place in Düsseldorf, Germany from November 14 – 17, 2016. This year, the DIARECT team is excited to present a brand new booth design, providing a welcoming atmosphere to all our visitors at booth 1/E19.
Well-established autoimmune antigens, as well as our new product line - human chimeric monoclonal antibodies - will be displayed. New additions to the infectious disease serology and allergy product lines will be presented.
For a first impression of our enlarged product portfolio, you are welcome to browse our new catalog, already available at the following link: Catalog.
To schedule personal appointments, or receive further information on our products, please contact us at:
Tel. +49 761 47979-0
Recombinant Allergens: Additions to our Popular Product Line
Most allergenic materials such as pollen and foods contain multiple allergenic proteins. The molecular identification of specific allergens and the subsequent establishment of Component Resolved Diagnosis (CRD) of allergies, allow the detection of and distinction between specific and cross-specific IgE antibodies (Canonica et al. 2013, Van Gasse et al. 2015, Werfel et al. 2015).
Food allergens in particular are known to be manifested in acute allergic reactions such as hives, bronchospasm and systemic anaphylaxis. In Northern Europe, where up to 30 - 40% of young adults are sensitized to birch pollen, pollen cross-sensitization to peanut is common. CRD may prove useful in distinguishing cross-sensitization from a life-threatening peanut allergy (Kukkonen et al. 2015).
DIARECT is pleased to announce an extended panel of recombinant food allergens for the molecular diagnostics of allergies. Moreover, selected grass and tree pollen allergens have been added to the existing panel.
For a complete list of our recombinant allergens please see below:
Canonica et al. (2013) World Allergy Organ Journal 6: 17
Kukkonen et al. (2015 ) Allergy DOI: 10.1111/all.12671
Van Gasse et al. (2015) Clinical Chim Acta 444: 54-61
Werfel et al. (2015) Allergy 70: 1079-1090
For additional product related information or updated product flyers please feel free to contact us at:
Tel: +49 761 47979-0
New Infectious Disease Antigens and Nomenclature Changes
Lyme Disease Spirochaete Taxonomy
According to the recent nomenclature changes to enable differentiation between Lyme Disease and Relapsing Fever spirochaetes (Adeolu and Gupta 2014, Oren and Garrity 2015), DIARECT, in concordance with these new guidelines has modified the product names of our existing Borrelia product line. Genus names of all Lyme borreliosis antigens will be changed to Borreliella spp.
Further, due to a taxonomic change on species level (Margos et al. 2009, Oren and Garrity 2015), the antigen Borrelia garinii p58 derived from the PBi strain, and already included in DIARECT’s product line of infectious disease antigens will be named Borreliella bavariensis p58 (see table below).
New Lyme Antigens – p28 and p30
Borreliella burgdorferi p28, also known as outer membrane porin Oms28, or BB_A74, was first identified by Skare et al. (1995) as virulent strain-associated outer membrane–spanning (Oms) protein, present in isolated outer membrane fractions. The surface-exposed lipoprotein contains 257 amino acids, has a molecular mass of 28 kDa and can be absent in some natural isolates of B. burgdorferi, due to lack of the encoding gene (Li et. al. 2007). Cluss et al. (2004) surmised that p28 plays an important role in host-pathogen interaction. Using black lipid membrane assays, Skare et al. (1996) showed that p28 is a membrane porin. Nevertheless, scientists are in disagreement about the function of p28 as Mulay et al. (2007) found that secondary structure of the p28 is mainly alpha-helical (78%) and lacks porin-like properties. They concluded p28 is a periplasmic protein associated with the outer membrane. Therefore, the function of the protein is not completely clear.
Immunofluorescence studies suggested that B. burgdorferi p30 is an outer surface protein (Das et al. 1996). Antibodies against p30 are recognized in app. 22% of Lyme borreliosis patients. Regardless, p30 is not detectable in all strains of B. burgdorferi. The encoding chromosomal gene is 801 nucleotides in length and has homology with periplasmic substrate-binding proteins of Gram-negative bacteria, which may explain possible function of the protein. The protein p30 contains 267 amino acids and the predicted molecular weight is 30 kDa. The putative substrate-binding protein is immunologically recognized in human and murine Lyme borreliosis.
To offer a more comprehensive spectrum of Borreliella antigens for assay development DIARECT is now introducing the recombinant Borreliella burgdorferi antigens p28 and p30, both expressed in E.coli (Figure).
Adeolu and Gupta (2014) Antonie van Leeuwenhoek 105: 1049–1072
Chandra et al. (2011) Clinical and Vaccine Immunology 18:767–771
Cluss et al. (2004) Infection and Immunity 72: 6279–6286
Das et al. (1996) Research in Microbiology 147: 739–751.
Li et al. (2007) Infection and Immunity 75: 4237–4244
Margos et al. (2009) Applied and Environmental Microbiology 75: 5410–5416
Mulay et al. (2007) Journal of Bacteriology 189: 2063–2068
Oren and Garrity (2015) Int. Journal of Systematic of Evolutionary Microbiology 65: 1105–1111
Skare et al. (1996) Journal of Bacteriology 178: 4909–4918
Skare et al. (1995) Journal of Clinical Investigation 96: 2380–2392
Product Launch: StabilBlock® Immunoassay Stabilizer
Expanding the Immunoassay Stabilizer product range, key benefits of the new SurModics IVD StabilBlock® Immunoassay Stabilizer are:
- minimizing non-specific binding
- maximizing signal-to-noise ratios within immunoassay applications
StabilBlock® effectively preserves, like StabilCoat® and StabilGuard®, the conformation and activity of dried proteins coated on a wide range of surfaces. At the same time, their blocking mechanisms reduce non-specific binding of interfering proteins to maximize assay sensitivity.
The formulation can be used to stabilize antibodies, antigens or enzymes to keep their peak performance for long durations on an assortment of immunoassay surfaces: polystyrene plates, tubes, glass, membranes, and filter paper. This increases manufacturing scale of your immunoassay and extends shelf lives for the end user.
The StabilBlock® formulation allows for these requirements to be accomplished in a single step while easily being substituted for the blocking solution in an existing assay protocol.
Evaluation samples are now available!