Related Experiment Video
Updated: Jan 28, 2026
Microscopy-based Assays for High-throughput Screening of Host Factors Involved in Brucella Infection of Hela Cells
Published on: August 5, 2016
Infection by Brucella melitensis or Brucella papionis modifies essential physiological functions of human
Karellen B García-Méndez1,2, Soledad M Hielpos1,2, Pedro F Soler-Llorens1
1VBMI, INSERM, Université de Montpellier, Nîmes, France.
Abstract:
Brucellosis is a zoonosis caused by bacteria of the Brucella genus. In ruminants, brucellosis causes abortion, followed by chronic infection and secretion of bacteria in milk. In humans, it usually presents as flu-like symptoms, with serious complications if untreated. Epidemiological studies have only recently established that brucellosis can also cause pregnancy complications in women, but the pathogenic mechanisms are unknown. Pioneering studies in ruminants showed that Brucella infect trophoblasts and then colonise the placenta where they grow to high density. A recent study showed that the main zoonotic Brucella species can infect human cytotrophoblasts (CTB) and extravillous trophoblasts (EVT). In this work, we show that Brucella papionis (associated with stillbirth in primates) also infects human trophoblasts. However, it replicates actively in CTB, whereas its replication is very restricted within EVT. We also observed alteration of several trophoblastic functions upon infection by B. papionis or Brucella melitensis (the most prevalent species in human brucellosis). Infection altered the production of hormones, the ability of CTB to form syncytiotrophoblasts, and the invasion capacity of EVT. We also found that infection can spread between different types of trophoblasts. These findings constitute a new step in understanding how Brucella infection causes adverse pregnancy outcomes.
Insights
Brucellosis bacteria infect human placental cells, impacting hormone production and cell function. This study reveals how Brucella papionis and Brucella melitensis contribute to adverse pregnancy outcomes.
Area of Science:
- Reproductive biology
- Infectious diseases
- Microbiology
Background:
- Brucellosis, a zoonotic disease, poses risks to human pregnancy, yet pathogenic mechanisms remain unclear.
- Brucella bacteria are known to infect placental cells in ruminants, leading to pregnancy complications.
- Previous studies show zoonotic Brucella species infect human cytotrophoblasts (CTB) and extravillous trophoblasts (EVT).
Purpose of the Study:
- To investigate the infection of human trophoblasts by Brucella papionis, a species linked to stillbirth in primates.
- To elucidate the pathogenic mechanisms by which Brucella species cause adverse pregnancy outcomes in humans.
Main Methods:
- Infection of human CTB and EVT with Brucella papionis and Brucella melitensis.
- Assessment of bacterial replication within different trophoblast cell types.
- Analysis of trophoblastic functions, including hormone production, syncytiotrophoblast formation, and EVT invasion capacity.
Main Results:
- Brucella papionis actively replicates in CTB but shows restricted replication in EVT.
- Infection by B. papionis or B. melitensis alters trophoblastic hormone production, CTB syncytiotrophoblast formation, and EVT invasion.
- Brucella infection can spread between different types of human trophoblasts.
Conclusions:
- Brucella papionis and Brucella melitensis infect and disrupt human trophoblast functions, contributing to adverse pregnancy outcomes.
- Understanding these interactions is crucial for developing strategies to prevent Brucellosis-related pregnancy complications.
Related Concept Videos
01:25Compounds Essential to Human Function
Inorganic Compounds Essential to Human Functioning
Inorganic compounds essential to human functioning include water, salts, acids, and bases. These compounds are inorganic, i.e., they do not have a carbon-hydrogen bond. Water...
01:27Physiology of Respiration I: Functions of the Respiratory System
Fundamental Processes in Respiration:
01:31Essential Minerals for Bone Health
Calcium and Phosphorus
Calcium is a critical component of bones, especially in the form of calcium phosphate and calcium carbonate. Since the body cannot make calcium, it must be obtained from the diet. However, calcium cannot be absorbed from the small intestine without...
01:25Physiological Barriers
The blood endothelial barrier is the most porous of these. It allows all small ionized, un-ionized, and lipophilic molecules to pass through the endothelial lining into the interstitial space...
01:24The Physiology of Taste
01:30Liver Physiology
Metabolic Regulation:
The liver is the central organ involved in regulating blood composition. It stabilizes blood glucose levels, maintaining them within the range of 70–110 mg/dL. When these levels drop, the liver breaks down glycogen reserves and releases glucose into the bloodstream. It can...