Lea-Ann Kirkham, Australia
West farmers Center of Vaccines and Infectious Diseases, Telethon Kids Institute, the University of Western Australia, Perth, Australia Telethon Kids InstituteAuthor Of 4 Presentations
LACK OF IMPACT OF PNEUMOCOCCAL CONJUGATE VACCINATION ON SEROTYPE-SPECIFIC PNEUMOCOCCAL CARRIAGE DENSITY IN PAPUA NEW GUINEAN INFANTS (ID 769)
- Kate Britton, Australia
- Janessa Pickering, Australia
- William Pomat, Papua New Guinea
- Camilla DeGier, Australia
- Monica L. Nation, Australia
- Casey L. Pell, Australia
- Caitlyn Granland, Australia
- Vela Solomon, Papua New Guinea
- Andrew R. Greenhill, Australia
- Peter Richmond, Australia
- Christopher C. Blyth, Australia
- Deborah Lehmann, Australia
- Catherine Satzke, Australia
- Lea-Ann Kirkham, Australia
DEVELOPMENT OF A MULTIPLEX BEAD-BASED IMMUNOASSAY TO MEASURE PNEUMOCOCCAL POLYSACCHARIDE ANTIBODY AVIDITY IN SMALL VOLUMES OF SERUM (ID 927)
Abstract
Background
Antibody avidity measures the strength of antibody-antigen binding, providing information on antibody quality. Usually avidity tests require large sample volumes, especially for multiple antigens, which is not suitable for paediatric studies. We investigated whether a bead-based avidity assay specific to pneumococcal polysaccharides could be developed using small volume samples.
Methods
Pneumococcal polysaccharides (1,3,4,5,6B,7F,9V,14,18C,19A,19F,23F) were modified with DMTMM (4-(4,6-dimethyl[1,3,5]triazin-2-yl)-4-methyl-morpholinium) and conjugated to carboxylated beads. 1M NaSCN was used to dissociate weak hydrogen bonds between antibody and antigen. The assay was validated on longitudinally collected sera from 6 pneumococcal conjugate vaccinated infants at 1,4,9,10,23,24 months of age. Avidity index (AI) was determined as the serum IgG titre that remained bound after NaSCN treatment compared to untreated serum.
Results
AIs against all 12 polysaccharides were obtained. In general, AIs increased following PCV immunisation. However, AIs were highly variable between children at each time-point. The lowest AIs were observed for serotype 1 and 3.
Conclusions
We have developed an assay that simultaneously measures antibody avidity for 12 pneumococcal polysaccharides in <5mL serum, and will now apply this assay to a cohort of PCV10- and PCV13-vaccinated children. This high-throughput assay may be a useful alternative measure of antibody quality compared to more technical assays such as multiplex-opsonophagocytosis.
ANTIMICROBIAL SUSCEPTIBILITY OF PNEUMOCOCCAL CARRIAGE ISOLATES AMONG PAPUA NEW GUINEAN CHILDREN VACCINATED WITH 10-VALENT OR 13-VALENT PNEUMOCOCCAL CONJUGATE VACCINES (PCVS) (ID 388)
- Tilda Orami, Papua New Guinea
- Audrey Michael, Papua New Guinea
- Rebecca Ford, Papua New Guinea
- Mition J. Yoannes, Papua New Guinea
- Vela Solomon, Papua New Guinea
- Gerard Saleu, Papua New Guinea
- Geraldine Masiria, Papua New Guinea
- Mary Dreyam, Papua New Guinea
- Birunu Nivio, Papua New Guinea
- Anita Van Den Biggelaar, Australia
- Lea-Ann Kirkham, Australia
- Andrew R. Greenhill, Australia
- Peter Richmond, Australia
- Deborah Lehmann, Australia
- Peter Siba, Papua New Guinea
- William Pomat, Papua New Guinea
HIGH PNEUMOCOCCAL CARRIAGE RATES WITH DIVERSE SEROTYPES IN PAPUA NEW GUINEANCHILDRENWITH PNEUMONIA IN A RANDOMIZED TRIAL OF 10-VALENT AND 13-VALENT PNEUMOCOCCAL CONJUGATE VACCINES (ID 430)
- Mition J. Yoannes, Papua New Guinea
- Rebecca Ford, Papua New Guinea
- Audrey Michael, Papua New Guinea
- Vela Solomon, Papua New Guinea
- Geraldine Masiria, Papua New Guinea
- Gerard Saleu, Papua New Guinea
- Mary Dreyam, Papua New Guinea
- Birunu Nivio, Papua New Guinea
- Peter Siba, Papua New Guinea
- Peter Richmond, Australia
- Lea-Ann Kirkham, Australia
- Andrew R. Greenhill, Australia
- Deborah Lehmann, Australia
- William Pomat, Papua New Guinea