IAU Symposium 160

Some of the topics considered include: Search Programs, Populations of Small Bodies, Dynamics, Physical Observations and Modeling, Observations from Space, Origin and Evolution, and Data Bases.Sponsored by International Astronomical Union.Organized by Osservatorio Astronomico di Torino and the Lunar and Planetary Institute.With the contribution of Regione Piemonte, Provincia di Novara, A.P.T. Lago Maggiore, Consiglio Nazionale delle Ricerche, European Space Agency, Alenia Spazio S.p.A.; with the participation of Banca Popolare di Novara, Camera di Commercio di Novara, Martini & Rossi IVLAS S.p.A.PARTIAL CONTENTS: SMACS: Small Missions to Asteroids and Comets. A Fast, Low Cost Approach to the Space Reconnaissance of Near-Earth Objects / M.J.S. Belton--Stochasticity of Comet P/GE-Wang / D. Benest and R. Gonczi--Chips Off of 4 Vesta: A Newly Confirmed Asteroid Family and Link to Basaltic Achondrite Meteorites / R.P. Binzel--Asteroid 243 IDA as a Member of the Koronis Family: Predictions and Implications for the Galileo Encounter / R.P. Binzel and S.M. Slivan--Photoelectric Observations of 4179 Toutatis / C. Blanco and D. Riccioli--Observations of OH in P/Swift-TuttIe and in Several Recent Weak Comets with the Nancay Radio Telescope / D. Bockehie-Morvan, G. Bourgois, P. Colom, J. Crovisier, E. Gerard, and L. Jorda--The Origin of the 3.2-3.6 Micron Emission Features in Comets: Gas or Dust / D. Bockelee-Morvan, T.Y. Brooke, and J. Crovisier--Observations of Sub-millimeter Lines of CH30H, HCN and H2CO in Comet P/Swift-Tuttle with the James Clerk Maxwell Telescope / D. Bockelee-Morvan, R. Padman, J.K. Davies, and J. Crovisier--Astrometric Measurements of Minor Planets in 1991-1992 / G. Bocsa and M. Birlan--Concerted Elemental Analyses- PIXE and TOF-SIMS- of Interplanetary Dust Particles / J. Bohsung, E.K. Jessberger, and T. Stephan--Dynamical Effects of Asymmetric Nongravitational Forces on Long-Period Comets / A. Bolalto, G. Carballo, and J.A. Fenuindez--Images of Comet Swift-Tuttle 1992t in the Light of H20+ and CO+ Ions, and Dust / T. Bonev, K. Jockers, and G.P. Chernova--Two Components in Meteor Spectra / J. Borovicka

Ultrasensitive detection of toxocara canis excretory-secretory antigens by a nanobody electrochemical magnetosensor assay.

peer reviewedHuman Toxocariasis (HT) is a zoonotic disease caused by the migration of the larval stage of the roundworm Toxocara canis in the human host. Despite of being the most cosmopolitan helminthiasis worldwide, its diagnosis is elusive. Currently, the detection of specific immunoglobulins IgG against the Toxocara Excretory-Secretory Antigens (TES), combined with clinical and epidemiological criteria is the only strategy to diagnose HT. Cross-reactivity with other parasites and the inability to distinguish between past and active infections are the main limitations of this approach. Here, we present a sensitive and specific novel strategy to detect and quantify TES, aiming to identify active cases of HT. High specificity is achieved by making use of nanobodies (Nbs), recombinant single variable domain antibodies obtained from camelids, that due to their small molecular size (15kDa) can recognize hidden epitopes not accessible to conventional antibodies. High sensitivity is attained by the design of an electrochemical magnetosensor with an amperometric readout with all components of the assay mixed in one single step. Through this strategy, 10-fold higher sensitivity than a conventional sandwich ELISA was achieved. The assay reached a limit of detection of 2 and15 pg/ml in PBST20 0.05% or serum, spiked with TES, respectively. These limits of detection are sufficient to detect clinically relevant toxocaral infections. Furthermore, our nanobodies showed no cross-reactivity with antigens from Ascaris lumbricoides or Ascaris suum. This is to our knowledge, the most sensitive method to detect and quantify TES so far, and has great potential to significantly improve diagnosis of HT. Moreover, the characteristics of our electrochemical assay are promising for the development of point of care diagnostic systems using nanobodies as a versatile and innovative alternative to antibodies. The next step will be the validation of the assay in clinical and epidemiological contexts