Study highlights microRNAs as key regulators in Klebsiella pneumoniae infections

A review in Biomolecules and Biomedicine sheds light on how microRNAs (miRNAs)—small regulatory RNA molecules—play a central role in the body’s response to Klebsiella pneumoniae, a major cause of hospital-acquired infections and rising antimicrobial resistance.

K. pneumoniae is a Gram-negative bacterium responsible for conditions such as pneumonia, sepsis, peritonitis, and urinary tract infections. Its ability to develop into multidrug-resistant and hypervirulent strains has made it a priority pathogen in health care settings worldwide.

Current treatments are increasingly compromised by antibiotic resistance, highlighting the urgent need for new diagnostic and therapeutic approaches.

The review explores recent research on miRNAs—molecules that control gene expression and influence immune responses—showing how they modulate inflammation, immune cell activation, and host-pathogen interactions during K. pneumoniae infection. These insights are helping researchers better understand how the body responds to infection and where intervention might be most effective.

“MicroRNAs are not just passive markers—they actively shape the course of infection,” said the study’s lead author. “They regulate cytokine production, immune signaling, and even post-translational modifications, giving us a new window into host-pathogen biology.”

Key findings:

• In lung infections, miRNAs such as miR-155, miR-23a, and miR-181a-5p influence inflammation and tissue injury by regulating signaling pathways like p38MAPK and STAT3.
• During sepsis, miRNAs have been linked to immune dysregulation and may serve as biomarkers for disease severity. For example, miR-155 affects neutrophil activity, while miR-7108-5p and miR-342-3p are associated with bacterial evasion from immune cells.
• In peritonitis, a range of miRNAs alter cytokine responses by targeting pathways such as TLR/IL-1 signaling, influencing the balance between immune activation and tolerance.
• The review also introduces the role of SUMOylation, a protein modification process that can be disrupted by certain miRNAs to either enhance or suppress immune responses.

Addressing the limitations of current therapies

Antibiotic treatments for K. pneumoniae infections are becoming less effective as resistance spreads globally. miRNAs offer a promising complement or alternative by providing new targets for modulating the immune system.

Researchers are now exploring miRNA-based diagnostics and therapeutic strategies, including the potential to enhance the body’s own defenses or reduce harmful inflammation.

“Targeting specific miRNAs could allow us to fine-tune the immune response without relying solely on antibiotics,” the authors noted. “This could be especially valuable in patients with multidrug-resistant infections.”

The findings support the development of miRNA-based diagnostic tools to predict infection severity, monitor treatment responses, or identify patients at risk of poor outcomes. Additionally, combining miRNA modulators with antibiotics may offer a synergistic approach to overcoming resistance and improving clinical efficacy.

As research continues to uncover the molecular details of how K. pneumoniae interacts with the host, miRNAs are emerging as powerful tools in the fight against infectious diseases.