Decoding T and B cell dynamics in inborn errors of immunity: insights into immune dysfunction

IntroductionInborn errors of immunity (IEI) often manifest through alterations in T and B lymphocyte subsets, complicating early diagnosis and management; this review aims to synthesize current knowledge on lymphocyte subgroup dynamics in combined immunodeficiencies (CID) and related disorders.Areas coveredWe surveyed peer-reviewed literature focusing on flow cytometric profiling of T and B cell subpopulations in IEI, including both syndromic and non-syndromic presentations. Key studies were identified through systematic searches of PubMed and Embase between 2000 and 2024, emphasizing quantitative and qualitative changes in naive, central memory, effector memory, and regulatory subsets. Data extraction prioritized correlations between immunophenotypic patterns and genetic defects, clinical phenotypes, and therapeutic interventions.Expert opinionDetailed immunophenotyping holds transformative potential to expedite IEI diagnosis and inform individualized treatment strategies. However, widespread implementation faces barriers such as inconsistent assay standardization, limited access to high-dimensional flow cytometry in resource-constrained settings, and incomplete genotype-phenotype mapping. Future research should integrate multi-omic profiling and machine learning to refine diagnostic algorithms, enabling earlier therapeutic interventions - including targeted biologics, gene therapy, and optimized hematopoietic stem cell transplantation protocols - to improve patient outcomes.