Listeria adhesion protein-expressing bioengineered probiotics prevent fetoplacental transmission of Listeria monocytogenes in a pregnant Guinea pig model. Academic Article uri icon


  • Pregnancy is a high-risk factor for foodborne pathogen Listeria monocytogenes (Lm), which causes abortion, premature birth, or stillbirth. The primary route of Lm transmission is oral hence intestinal epithelial barrier crossing is a prerequisite for systemic spread. Intestinal barrier crossing, in part, is attributed to the interaction of Listeria adhesion protein (LAP) with its cognate receptor, Hsp60. In a recent study, we showed that oral-dosing of bioengineered Lactobacillus caseiprobiotic (BLP) expressing the LAP protected nonpregnant mice from lethal infection; however, its ability to prevent listeriosis during pregnancy is not known. Therefore, we investigated whether BLP could prevent fetoplacental transmission of Lm in a pregnant guinea pig model. After 14 consecutive days on probiotic (~109CFU/ml in drinking water), pregnant guinea pigs (gestational days 24-28) were orally challenged with Lm (9108-2.5109CFU/animal) and were euthanized 72h post-infection. Maternal mesenteric lymph node (MLN), liver, spleen, lungs, blood, and placenta, and fetal liver were analyzed for the presence/absence of Lm. All tissues/organs from Lm-challenged nave dams and fetuses were Lm positive. Similar tissue distribution was also seen in guinea pigs that received wild-type Lactobacillus casei (LbcWT). Remarkably, Lm was absent in the maternal blood, kidney, lungs, and placenta, and fetal liver from the BLP-fed group even though the Lm was present in the maternal liver, spleen, and MLN. BLP feeding also suppressed Lm-induced inflammatory response in mothers. These data highlight the potential for the prevention of fetoplacental transmission of Lm by LAP-expressing BLP during pregnancy.

published proceedings

  • Microb Pathog

author list (cited authors)

  • Ryan, V. E., Bailey, T. W., Liu, D., Vemulapalli, T., Cooper, B., Cox, A. D., & Bhunia, A. K.

citation count

  • 3

complete list of authors

  • Ryan, Valerie E||Bailey, Taylor W||Liu, Dongqi||Vemulapalli, Tracy||Cooper, Bruce||Cox, Abigail D||Bhunia, Arun K

publication date

  • January 2020