Anticorpi anti-Helicobacter pylori IgG, Microblot (CagA, VacA, UreA, NAP, HpaA, HcpC, GroEL)

Helicobacter pylori is a Gram-negative bacterium that colonizes the human gastric mucosa and is one of the most common bacterial infections worldwide. Transmission occurs primarily via fecal-oral and oral-oral routes.

H. pylori infection is associated with chronic inflammation of the gastric and duodenal mucosa and is the main etiological factor of chronic gastritis, as well as a major contributor to gastric and duodenal peptic ulcer disease. Persistent infection is associated with an increased risk of gastric adenocarcinoma and MALT lymphoma.

IgG antibodies to Helicobacter pylori, detected by the Microblot (immunoblot) method, reflect the systemic immune response to infection and are used in the serological diagnosis of chronic infection. The test identifies an extended IgG antibody profile against specific bacterial antigens and virulence factors, including CagA, VacA, UreA, NAP, HpaA, HcpC, and GroEL.

• CagA (p120) - major virulence factor associated with severe gastric inflammation, peptic ulcer disease, premalignant lesions, and increased risk of gastric adenocarcinoma
• VacA (p87) - cytotoxin involved in epithelial cell damage, vacuolization, mitochondrial dysfunction, and apoptosis
• UreA (p29) - urease subunit enabling bacterial survival in the acidic gastric environment through acid neutralization
• NAP - neutrophil-activating protein involved in inflammatory response of the gastric mucosa
• HpaA - adhesin responsible for bacterial attachment to gastric epithelium
• HcpC - immunogenic protein associated with chronic infection and host–pathogen interaction
• GroEL - heat shock protein (chaperonin) involved in bacterial stress adaptation and immune response

The presence of IgG antibodies indicates current or past exposure to H. pylori. However, serology cannot confirm active infection, as antibodies may persist after eradication. For confirmation of active infection, urea breath test, stool antigen testing, or endoscopic methods are recommended depending on clinical indication.

Indications

• suspected Helicobacter pylori infection
• chronic gastritis
• gastric and duodenal peptic ulcer disease
• dyspeptic symptoms (epigastric pain, heartburn, nausea, postprandial discomfort)
• clinical screening
• evaluation of chronic H. pylori infection

Procedure
Venous blood sampling under standard laboratory conditions.

Method
Immunoblot (Microblot), detection of IgG antibodies to Helicobacter pylori antigens.