# Adaptive Immunity > See also: [[Innate Immunity]] The **adaptive immune system** is - Slow response ranging from days to weeks - Variable *(Changing of T and B cell receptors)* - Numerous highly selective specificities - Improve during the course of response The primary cells of the adaptive immune response are [[The Lymphatic System]] (primarily T and B cells) These cells act as highly specific receptors for one type of pathogen. Your body is capable of forming billions of different variations of these receptors to recognize and attack a specific pathogen. [[The Lymphatic System]] is what allows the lymphocytes and other relevant [[cells of the immune system]] to travel through the body and quickly arrive at sites of infection. ## Cell-Mediated Immunity > See also: > - [[T-Cells]] ## Humoral-Mediated Immunity > See also: > - [[The Complement System]]