Role of Staphylococcus aureus and Streptococcus pyogenes Biofilms on the Alternation of Cellular Immunity in Pediat-ric Tonsillitis Patients

This study examines the effect of Staphylococcus aureus and Streptococcus pyogenes biofilms on cellular hematological parameters and distribution and phenotyping of cellular immunity in mucosal tissue of tonsils. Thirty healthy controls and fifty pediatric tonsillitis patients participated in the research. Thirty isolated S. aureus and S. pyogenes were tested for biofilm-forming capability (BFC). Hematological parameters were assessed before tonsillectomy, and 9 tonsil samples were evaluated using hematoxylin and eosin stain to investigate the histopathological alterations. Immunohistochemistry (IHC) staining was carried out for detecting dendritic cells (CD1a), neutrophils (CD15), macrophages (CD68), helper T cells (CD4), and cytotoxic T cells (CD8). Hematological parameters showed a significant increase in total WBC count in pediatric tonsillitis patients infected with S. aureus, mixed bacteria, and S. pyogenes groups. Both S. aureus and S. pyogenes had the ability to form biofilms with different capacities. 72% of the S. aureus isolates showed a moderate BFC compared to 23% strong and 5% with weak ability. While 50% of S. pyogenes showed strong BFC compared to 37% moderate and 13% with weak ability. The biofilms' effect on immune cells CD1a and CD15 showed weak positive staining, while CD68, CD4, and CD8 showed positive to strong positive staining. This study confirmed the capability of S. aureus and S. pyogenes to form biofilms with different effects on the immune cells in palatine tonsils of children, and the decreased number of dendritic cells (CD1a) and neutrophils (CD15) influence phagocytosis and antigen processing and presenting, which confirmed the association between BFC and the persistent nature of infection. Understanding a pathogen's BFC may guide clinicians to implement more aggressive or combination therapies to improve patient management and outcomes in the treatment strategies.