CD4 T cell phenotype after AS01-adjuvanted immunization is shaped by prior antigen or pathogen exposure
By
Robbert G. van der Most
Geert Leroux-Roels
June 22, 2026
Clinical Report: Influence of Previous Antigen or Pathogen Exposure on CD4 T Cell Phenotype Following AS01-Adjuvanted Vaccination
Background CD4 T-cell responses are crucial for the efficacy of many vaccines, particularly in the context of infectious diseases. The AS01 adjuvant is utilized in several licensed vaccines, enhancing both the quantity and quality of these immune responses. Understanding how previous exposure to pathogens or antigens affects vaccine responses is essential for developing effective vaccination strategies.
Data Highlights No numerical data or trial data was provided in the source material.
Key Findings AS01 adjuvant enhances antigen-specific polyfunctional CD4 T-cell immunity. Prior exposure to pathogens increases the capacity of vaccine-induced CD4 T cells to produce interferon-γ. Vaccine responses vary significantly between immunologically naïve and pathogen-primed individuals. Pre-existing immune memory influences the quality and quantity of CD4 T-cell responses. Different populations, including infants and immunocompromised individuals, show varied responses to AS01-adjuvanted vaccines. Clinical Implications Healthcare professionals should consider the immunological background of individuals when administering AS01-adjuvanted vaccines.
Conclusion Understanding pre-existing immune memory is important for optimizing CD4 T-cell responses to AS01-adjuvanted vaccines.
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