Morbidity and mortality of preterm and newborn infants remain significant public health concerns. Streptococcus agalactiae or Group B Streptococcus (GBS) are a leading cause of bacterial infection associated preterm births, stillbirths and early onset sepsis. We recently showed that increased expression of the hyaluronidase can be associated with GBS invasive disease and induces fetal demise in pregnant mice. The objective of this proposal is to understand how the GBS hyaluronidase subverts the function of multiple host innate immune cells to induce fetal injury and systemic infection.
Aim 1 will define mechanisms by which the GBS hyaluronidase subverts immune cell function and immune cell recruitment.
Aim 2 will establish how expression of the GBS hyaluronidase promotes microbial invasion of the amniotic cavity and fetal injury in the pregnant nonhuman primate model that closely emulates human pregnancy. These studies will provide novel insight into mechanisms of immune evasion during GBS infections. These results are essential and invaluable for development of novel therapeutic approaches to reduce the risk of GBS infection associated fetal injury, stillbirth, preterm births and neonatal infections.

Public Health Relevance

Understanding how pathogen encoded hyaluronidase affects immune cell function and recruitment will be invaluable for the development of therapeutic strategies to prevent Group B Streptococcal infections that include preterm births, stillbirths, and neonatal disease.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI133976-03
Application #
9696340
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
GU, Xin-Xing
Project Start
2017-06-20
Project End
2022-05-31
Budget Start
2019-06-01
Budget End
2020-05-31
Support Year
3
Fiscal Year
2019
Total Cost
Indirect Cost
Name
Seattle Children's Hospital
Department
Type
DUNS #
048682157
City
Seattle
State
WA
Country
United States
Zip Code
98105
Vornhagen, Jay; Quach, Phoenicia; Santana-Ufret, VerĂ³nica et al. (2018) Human Cervical Mucus Plugs Exhibit Insufficiencies in Antimicrobial Activity Towards Group B Streptococcus. J Infect Dis 217:1626-1636
Gendrin, Claire; Merillat, Sean; Vornhagen, Jay et al. (2018) Diminished Capsule Exacerbates Virulence, Blood-Brain Barrier Penetration, Intracellular Persistence, and Antibiotic Evasion of Hyperhemolytic Group B Streptococci. J Infect Dis 217:1128-1138
Mitchell, Timothy; MacDonald, James W; Srinouanpranchanh, Sengkeo et al. (2018) Evidence of cardiac involvement in the fetal inflammatory response syndrome: disruption of gene networks programming cardiac development in nonhuman primates. Am J Obstet Gynecol 218:438.e1-438.e16
Walker, Christie L; Merriam, Audrey A; Ohuma, Eric O et al. (2018) Femur-sparing pattern of abnormal fetal growth in pregnant women from New York City after maternal Zika virus infection. Am J Obstet Gynecol 219:187.e1-187.e20
Adams Waldorf, Kristina M; Olson, Erin M; Nelson, Branden R et al. (2018) The Aftermath of Zika: Need for Long-Term Monitoring of Exposed Children. Trends Microbiol 26:729-732
Vornhagen, Jay; Armistead, Blair; Santana-Ufret, VerĂ³nica et al. (2018) Group B streptococcus exploits vaginal epithelial exfoliation for ascending infection. J Clin Invest 128:1985-1999