Torunn Hjøllo1, Eirik Bratland2, Hans Steinsland3, Matej Radunovic2, Nina Langeland4, Kurt Hanevik4. 1. Department of Clinical Science, Faculty of Medicine, University of Bergen, Bergen, Norway. Electronic address: torunn.hjollo@uib.no. 2. Department of Clinical Science, Faculty of Medicine, University of Bergen, Bergen, Norway. 3. Centre for International Health, Department of Global Public Health and Primary Care, University of Bergen, Norway; Department of Biomedicine, University of Bergen, Bergen, Norway. 4. Department of Clinical Science, Faculty of Medicine, University of Bergen, Bergen, Norway; Norwegian National Advisory Unit on Tropical Infectious Diseases, Department of Medicine, Haukeland University Hospital, Bergen, Norway.
Abstract
INTRODUCTION/AIMS: The long-term humoral immune response after a natural giardiasis infection is not well understood. The aim of this study was to evaluate longitudinal serum IgA and IgG/M responses towards conserved regions of two Giardia variant-specific surface proteins (VSP) and whether these responses differ between Giardia assemblages and durations of infection. METHODS: We recruited thirty Giardia-positive patients, mainly returning travellers, and eighteen healthy adults presumed to be Giardia unexposed. Blood samples were collected before treatment, and at 6 weeks, 6 months and 12 months after the infection cleared. We used a multiplex bead-based flow cytometry immunoassay to measure Giardia specific IgA and IgG/M responses targeting two recombinant antigens from G. lamblia VSP proteins 3 and 5 (VSP3 and VSP5). RESULTS: Serum levels of anti-VSP5 and anti-VSP3 IgA decreased rapidly to low levels after treatment but continued to be substantially higher than that of presumed unexposed controls even after 6 and 12 months. The IgG/M response decreased more gradually but remained significantly higher than presumed unexposed controls at all time points, except for anti-VSP3 at 12 months. There were no significant difference in responses for infections with assemblage A and assemblage B Giardia lamblia. Chronic infections (>8 weeks) were associated with a significantly lower anti-VSP5 IgG/M response. CONCLUSION: This study describes the kinetics of the humoral immune response against two Giardia VSP proteins over one year, and the considerable cross reactivity between the two human infective Giardia assemblages. Persons with chronic Giardia infection seem to have lower levels of VSP antibodies.
INTRODUCTION/AIMS: The long-term humoral immune response after a natural giardiasis infection is not well understood. The aim of this study was to evaluate longitudinal serum IgA and IgG/M responses towards conserved regions of two Giardia variant-specific surface proteins (VSP) and whether these responses differ between Giardia assemblages and durations of infection. METHODS: We recruited thirty Giardia-positivepatients, mainly returning travellers, and eighteen healthy adults presumed to be Giardia unexposed. Blood samples were collected before treatment, and at 6 weeks, 6 months and 12 months after the infection cleared. We used a multiplex bead-based flow cytometry immunoassay to measure Giardia specific IgA and IgG/M responses targeting two recombinant antigens from G. lamblia VSP proteins 3 and 5 (VSP3 and VSP5). RESULTS: Serum levels of anti-VSP5 and anti-VSP3 IgA decreased rapidly to low levels after treatment but continued to be substantially higher than that of presumed unexposed controls even after 6 and 12 months. The IgG/M response decreased more gradually but remained significantly higher than presumed unexposed controls at all time points, except for anti-VSP3 at 12 months. There were no significant difference in responses for infections with assemblage A and assemblage B Giardia lamblia. Chronic infections (>8 weeks) were associated with a significantly lower anti-VSP5 IgG/M response. CONCLUSION: This study describes the kinetics of the humoral immune response against two Giardia VSP proteins over one year, and the considerable cross reactivity between the two humaninfective Giardia assemblages. Persons with chronic Giardia infection seem to have lower levels of VSP antibodies.
Authors: Barbara J Davids; Ching M Liu; Elaine M Hanson; Christine H Y Le; Jonathan Ang; Kurt Hanevik; Marvin Fischer; Matej Radunovic; Nina Langeland; Marcela Ferella; Staffan G Svärd; Majid Ghassemian; Yukiko Miyamoto; Lars Eckmann Journal: Infect Immun Date: 2019-05-21 Impact factor: 3.441
Authors: Benjamin F Arnold; Diana L Martin; Jane Juma; Harran Mkocha; John B Ochieng; Gretchen M Cooley; Richard Omore; E Brook Goodhew; Jamae F Morris; Veronica Costantini; Jan Vinjé; Patrick J Lammie; Jeffrey W Priest Journal: Elife Date: 2019-08-19 Impact factor: 8.140
Authors: Sozaburo Ihara; Yukiko Miyamoto; Christine H Y Le; Vivien N Tran; Elaine M Hanson; Marvin Fischer; Kurt Hanevik; Lars Eckmann Journal: PLoS Negl Trop Dis Date: 2022-04-25