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Updated: Jul 19, 2026

Implementation of a Permeable Membrane Insert-based Infection System to Study the Effects of Secreted Bacterial Toxins on Mammalian Host Cells
Published on: August 19, 2016
Dynamics of the immune response against extracellular products of group A streptococci during infection
Linda Maripuu1, Anna Eriksson, Björn Eriksson
1Department of Clinical Bacteriology, Umeå University, 901 85 Umeå, Sweden.
Abstract:
The immune response against the infecting group A streptococcus (GAS) extracellular products (EP) was determined in acute- and convalescent-phase sera from 75 patients with different clinical manifestations of GAS infection. All EP elicited a high proliferative response in human peripheral blood mononuclear cells. In patients with bacteremia, low neutralization in acute-phase sera was associated with development of streptococcal toxic shock syndrome. Lack of neutralization in acute-phase sera was more common in patients infected with the T1emm1 serotype. The majority of patients did not develop the ability to neutralize the mitogenic activity of their infecting isolate despite a significant increase in enzyme-linked immunosorbent assay titer in early convalescent-phase sera. In patients with the ability to neutralize GAS EP, the immune response remained high over at least 3 years. In contrast, the neutralization capacity conferred by intravenous immunoglobulin and/or plasma treatment disappeared within 3 months.
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