Immune response, neuronal regulation

Homo sapiens (compared to Drosophila melanogaster) Large-scale gene duplications with substantial expansion of genes involved in acquired immune response (B cells, T cells, major histocompatibility complex genes, cytokines, chemokines and their receptors), plasma proteases (complement and hemostatic proteins), proteins associated with apoptotic regulation and proteins related to neuronal network formation and electrical coupling... 

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... 

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