Related Experiment Video

Updated: Jul 1, 2026

Inducing Meningococcal Meningitis Serogroup C in Mice via Intracisternal Delivery
10:03

Inducing Meningococcal Meningitis Serogroup C in Mice via Intracisternal Delivery

Published on: November 5, 2019

Meningococcal outer membrane protein NhhA is essential for colonization and disease by preventing phagocytosis and

Hong Sjölinder1, Jens Eriksson, Lisa Maudsdotter

  • 1Department of Medical Biochemistry and Microbiology, Biomedical Centrum, Uppsala University, P.O. Box 582, Uppsala, Sweden.

Infection and Immunity
|September 17, 2008
PubMed

Insights

The meningococcal protein NhhA is crucial for Neisseria meningitidis to colonize the nose and cause sepsis. It helps bacteria evade immune responses like phagocytosis and complement-mediated killing.

Area of Science:

  • Microbiology
  • Immunology
  • Pathogenesis

Background:

  • Neisseria meningitidis causes meningitis and septicemia globally.
  • NhhA is an outer membrane protein involved in bacterial adhesion.

Purpose of the Study:

  • To investigate the role of NhhA in meningococcal disease pathogenesis.
  • To determine how NhhA contributes to bacterial survival and virulence.

Main Methods:

  • Utilized a murine model of meningococcal disease.
  • Assessed bacterial colonization, phagocytosis resistance, and serum resistance.

Main Results:

  • NhhA is essential for nasopharyngeal colonization in vivo.
  • NhhA protects bacteria from phagocytosis and complement-mediated killing.
  • NhhA enhances serum resistance, preventing membrane attack complex deposition.

Conclusions:

  • NhhA is a key virulence factor for Neisseria meningitidis.
  • NhhA promotes bacterial survival by inhibiting host immune responses.
  • NhhA contributes to both mucosal colonization and sepsis development.

More Related Videos

Humanized Mouse Model to Study Bacterial Infections Targeting the Microvasculature11:40

Humanized Mouse Model to Study Bacterial Infections Targeting the Microvasculature

Published on: April 1, 2014

Neisseria meningitidis Infection of Induced Pluripotent Stem-Cell Derived Brain Endothelial Cells10:12

Neisseria meningitidis Infection of Induced Pluripotent Stem-Cell Derived Brain Endothelial Cells

Published on: July 14, 2020

Related Concept Videos

Bacterial Meningitis II: Pathophysiology01:26

Bacterial Meningitis II: Pathophysiology

Bacterial meningitis typically begins when pathogens such as Neisseria meningitidis and Streptococcus pneumoniae colonize the nasopharynx and invade the bloodstream. This process is facilitated by bacterial virulence factors, such as polysaccharide capsules, which resist phagocytosis and complement-mediated killing. Less commonly, bacteria reach the central nervous system via contiguous spread from infections like otitis media or sinusitis, through congenital or acquired dural defects, or...
Bacterial Meningitis01:24

Bacterial Meningitis

Bacterial meningitis is a severe infectious disease involving inflammation of the meninges, the protective membranes surrounding the brain and spinal cord. It occurs when pathogenic bacteria cross the blood–brain barrier and enter the cerebrospinal fluid. Common causative organisms include Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae type b, Listeria monocytogenes, and Escherichia coli K1. The exact route of entry varies by pathogen and host condition.Routes of Entry...
Formation of Lipopolysaccharides01:19

Formation of Lipopolysaccharides

Lipopolysaccharides (LPS) are crucial components of the outer membrane of Gram-negative bacteria, serving both structural and functional roles. It contributes to membrane stability and protects bacteria from host immune responses. LPS is composed of three major regions—lipid A, a core oligosaccharide, and an O antigen. The biosynthesis and assembly of LPS involve a highly coordinated set of enzymatic reactions and transport mechanisms. Additionally, LPS is recognized as an endotoxin, triggering...
Colonisation of Pathogens01:25

Colonisation of Pathogens

Pathogen colonization of host tissues is a critical step in the development of infectious diseases. Various pathogenic microorganisms, including bacteria, fungi, viruses, and protozoa, have evolved complex strategies to attach to, invade, and persist within host environments. These mechanisms enable pathogens to establish infections, evade immune responses, and resist antimicrobial treatments.Attachment to Host CellsIn bacteria, colonization typically begins with adherence to host epithelial...
Cryptococcal Meningitis01:27

Cryptococcal Meningitis

Cryptococcal meningitis is a life-threatening opportunistic infection predominantly associated with HIV/AIDS, accounting for over 100,000 deaths annually worldwide. However, it also affects individuals with other forms of immunosuppression, including those undergoing immunosuppressive therapy, organ transplant recipients, patients with innate immunodeficiencies, and individuals with hematological disorders. The infection is caused mainly by Cryptococcus neoformans and Cryptococcus gattii,...
Determinants of Bacterial Pathogenicity and Virulence01:20

Determinants of Bacterial Pathogenicity and Virulence

Pathogenic bacteria employ a variety of strategies to establish infections, including the secretion of extracellular enzymes that act as potent virulence factors. These enzymes facilitate bacterial colonization of host tissues and help evade immune surveillance. By targeting structural components of host tissues and interfering with immune mechanisms, these enzymes play a pivotal role in disease progression.Extracellular Enzymes Facilitating Tissue Invasion: Several bacterial pathogens secrete...