An immune system may undergo a working.Logical formLearned from9 sentences. Persons can be immune to a virus.Logical formLearned from9 sentences. A person can be immune for life.Logical formLearned from9 sentences. Signalings can be between immune cells.Logical formLearned from9 sentences. Immune systems may get a chance.Logical formLearned from9 sentences. A protein may stimulate cells of an immune system.Logical formLearned from9 sentences. Patients may have immune systems.Logical formLearned from9 sentences. An immune response can be chronic.Logical formLearned from9 sentences. A complexity may pertain-to an immune system.Logical formLearned from9 sentences. Immune systems can be ravaged.Logical formLearned from9 sentences. An immune system may undergo (building blocks).Logical formLearned from9 sentences. Immune cells can be regulatory.Logical formLearned from9 sentences. A group of persons can be immune from dangers of collective hysteria.Logical formLearned from9 sentences. An immune system may overreact to substances.Logical formLearned from9 sentences. An influence can be on an immune system.Logical formLearned from9 sentences.