Immune response processes, cells involve

Stress is also involved in the modulation of the immune responses through mechanisms involving the neurotransmitter serotonin. This is a biologically active amine that plays a prominent role in the regulation of processes such as mood, appetite and sleep. During neurotransmission, serotonin is released from neurons into the synaptic cleft between cells. The amount of serotonin available for neurotransmission in the synaptic cleft is regulated largely by the serotonin transporter involved in the reuptake of serotonin after it has been released.23... 

Despite its considerable involvement in metabolic processes, no specific deficiency syndrome in humans has been attributed to vitamin B6 (19,103). A considerable number of nonvitamin functions have been suggested, but they remain controversial (102,103,108-111). These include roles in coronary heart disease, immune response, premenstrual syndrome, sickle-cell anaemia, asthma, autism, gestational diabetes, carpal tunnel syndrome, and cancer. 

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