Multiple leucocyte activation markers to detect neonatal infection

Area of Science:

• Immunology
• Neonatal Medicine
• Infectious Diseases

Background:

• Clinical signs for diagnosing neonatal infections are often non-specific.
• Current laboratory tests for early diagnosis of neonatal infections may be inadequate.
• Activated lymphocytes offer a rapid method for infection detection before organism isolation.

Purpose of the Study:

• To improve the sensitivity of neonatal infection screening tests.
• To identify specific leucocyte subsets involved in the immune response to infection.
• To evaluate a comprehensive range of surface activation markers on T cells, monocytes, and NK cells.

Main Methods:

• Studied up-regulation of surface activation markers on T cells, monocytes, and NK cells.
• Included 17 newborns with positive cultures, 40 with clinical signs of infection, and a control group.
• Established 'normal' ranges for activation markers in preterm and full-term newborns.

Main Results:

• Up-regulation of CD69 on NK cells was the most sensitive marker for neonatal sepsis (13/16 patients).
• Increased CD69 and CD25 expression on T cells observed in 11/17 and 10/17 patients, respectively.
• A combination of NK cell CD69 and T cell activation markers (CD45RA, CD45RO, CD25, CD69) showed high sensitivity and specificity.

Conclusions:

• CD69 up-regulation on NK cells is a novel and sensitive marker for neonatal infection.
• Combining NK cell CD69 with T cell activation markers provides a highly sensitive and specific diagnostic tool for neonatal infections.
• This approach enhances early and reliable diagnosis of neonatal infections.