Enhancement of human polymorphonuclear leucocyte motility by erythromycin in vitro and in vivo
Related Experiment Video
Updated: Aug 18, 2026
Analyzing the Effects of Stromal Cells on the Recruitment of Leukocytes from Flow
Published on: January 7, 2015
Abstract:
The effects of erythromycin on the migration, phagocytosis and antimicrobial activity of human polymorphonuclear leucocytes (PMNLs) were investigated in vitro. Therapeutic concentrations of erythromycin potentiated PMNL staphylocidal activity without affecting phagocytosis. PMNL random motility and migration to leuco-attractant endotoxin-activated serum (EAS) were significantly enhanced by erythromycin at concentrations of greater than 5 x 10(-5)M (16,5 micrograms/ml). To assess the possible in vivo significance of these findings the same PMNL functions were investigated in healthy adult volunteers before and 90 minutes and 1 week after the ingestion of a single 500 mg tablet of erythromycin stearate. PMNL migration to EAS and antimicrobial activity were significantly increased after ingestion of erythromycin and eventually returned to normal levels. A single intraperitoneal injection of 1,5 mg erythromycin lactobionate significantly increased the mean survival time of mice experimentally infected with Candida albicans. These micro-organisms are resistant to the antimicrobial effects of erythromycin. These findings show that erythromycin possesses nonspecific immunopotentiating properties which may contribute to the antimicrobial activity of this antibiotic.
Insights
Erythromycin enhances immune cell function, boosting the body's defense against infections. This antibiotic shows potential as an immunomodulator, improving the effectiveness of the immune system.
Area of Science:
- Immunology
- Pharmacology
- Microbiology
Background:
- Human polymorphonuclear leucocytes (PMNLs) are crucial for innate immunity.
- Erythromycin is a widely used antibiotic with known antimicrobial properties.
Purpose of the Study:
- To investigate the in vitro and in vivo effects of erythromycin on PMNL functions.
- To determine if erythromycin possesses immunomodulatory effects beyond its direct antimicrobial activity.
Main Methods:
- In vitro studies assessed PMNL migration, phagocytosis, and staphylocidal activity.
- In vivo studies involved healthy volunteers and a mouse model infected with Candida albicans.
- Erythromycin concentrations and PMNL functions were measured before and after treatment.
Main Results:
- Erythromycin enhanced PMNL staphylocidal activity and migration in vitro.
- In vivo, erythromycin increased PMNL migration and antimicrobial activity in healthy volunteers.
- Erythromycin administration improved survival rates in mice infected with Candida albicans, an organism resistant to erythromycin.
Conclusions:
- Erythromycin exhibits non-specific immunopotentiating properties.
- These immune-enhancing effects may contribute to the overall therapeutic efficacy of erythromycin.
- Erythromycin could be considered an immunomodulatory agent in addition to its antibiotic function.
