Here, we evaluated the expression of various 5-HT receptors by Eos from donors with asthma and/or rhinitis (n = 5) by RT-PCR with primers specific for each subtype and found that human Eos express 5-HT1A, 5-HT1B, 5-HT1E, 5-HT2A, 5-HT2B and 5-HT6 receptors with 5-HT2A being the most predominantly expressed, albeit at variable levels among the different donors (Fig. 1, A). Here, HTR1B is linked to rhinitis.