To determine the role of PLXNB2 in sensitizing mice to the development of asthma, mice were intranasally treated with either PBS or PLXNB2 (300 ng) on days 0, 3, 6 and 9; challenged with OVA on days 11, 12 and 13; and killed on day 14 (Figure 4D). This evidence concerns the gene PLXNB2 and asthma.