Untangling Neutrophil Clues to Increased Bacterial Infections in CLL
Posted: Tuesday, April 27, 2021
Patients with chronic lymphocytic leukemia (CLL) tend to be more prone than other individuals to develop frequent and severe bacterial infections, possibly because the malignancy represses the strong antibacterial function of neutrophils. Daniel Robert Engel, PhD, of University Hospital Essen, Germany, and colleagues sought to learn more about the underlying phenotypical and functional changes in the affected neutrophils.
Using a mouse model and bioinformatic analysis of the neutrophil proteome, they learned, among other findings, that CLL progression reduces neutrophils’ expression of CD62L and CXCR4. In turn, they described in Blood Advances that this might be associated with impairment of the ability of the neutrophils to migrate to an area of infection—in this case, the urinary bladder because mice were engineered to have CLL as well as urinary tract infections caused by Escherichia coli.
The researchers explained that they also found increased expression of proteins associated with interferon signaling, corresponding to greater suppression of neutrophils. Taken together, the results of the study “provide a molecular signature of neutrophils in CLL with a broad range of proteins with biomarker or therapeutic potential, such as interferon-induced protein with tetratricopeptide repeats, ISG15, ceruloplasmin, hemopexin, and GRB2.”
In patients with CLL, serious lung infections can lead to life-threatening complications. The data generated by this work, according to Dr. Engel and colleagues, could be important in addressing infections there and in other organs beyond the urinary tract. Additional studies building on this new knowledge are necessary, they concluded.
Disclosure: The study authors’ disclosure information can be found at ashpublications.org.