Dynamical modeling and data analysis of HIV infection with infection-age, CTLs immune response and delayed antibody immune response.

HIV infection, a leading cause of AIDS, continues to impose a substantial global health burden. This study investigates the mechanisms of HIV infection and immune responses through a delayed infection-age structured model that integrates viral target cell infection, CTLs-mediated immunity, and delayed antibody immune responses. We rigorously analyze the existence, uniqueness, and boundedness of the model's solution semi-flow, followed by detailed examinations of equilibrium states coexistence and local stability. Using clinical HIV case data from Jiangsu Province, we estimate model parameters and assess fitting accuracy. The model successfully replicates key clinical manifestations in four ART-treated patients, underscoring its medical relevance. Our findings suggest that ART efficacy primarily manifests in reduced infection rates and viral release rates. Notably, reverse transcriptase inhibitors, fusion inhibitors, and entry inhibitors demonstrate significantly superior therapeutic efficacy compared to protease inhibitors and treatments targeting drug-resistant viral strains. Moreover, ART exhibits significantly stronger enhancement of cellular immunity (particularly CD8+ T cell responses) than modulation of humoral immunity, viral reservoirs persist despite potent antiretroviral suppression.