Human adaptive immune system

The human adaptive immune system is a complex network of specialized cells and processes that provides long-term protection against specific pathogens through the generation of immunological memory. When targeted by live-attenuated poliovirus types 1, 2, and 3—the components of the Oral Poliovirus Vaccine (OPV)—the system initiates a robust response involving both B-cell mediated antibody production and T-cell activation (StatPearls, 2023). This interaction is unique because the attenuated virus replicates within the gastrointestinal tract, effectively inducing mucosal immunity (secretory IgA) which is essential for blocking person-to-person transmission (WHO, 2022). The primary therapeutic goal of stimulating this system is the prevention of poliomyelitis, a disease characterized by viral invasion of the central nervous system and subsequent motor neuron destruction (CDC, 2023). However, the use of live-attenuated strains presents significant safety challenges, including the rare occurrence of vaccine-associated paralytic poliomyelitis (VAPP) and the potential for the virus to regain virulence and circulate as vaccine-derived poliovirus (cVDPV) (Nature Reviews Microbiology, 2018). Consequently, while the adaptive immune system is the functional target for achieving polio eradication, the transition to inactivated vaccines is often required to mitigate these specific risks in the final stages of global health initiatives.

Other names

Adaptive immunityAcquired immune systemSpecific immune system

Induction of mucosal and systemic immunity through the presentation of viral antigens to B and T cells following replication of attenuated virus in the gastrointestinal tract.