Methods for assaying a donor lung for chronic allograft lung dysfunction (CLAD) optionally bronchiolitis obliterans syndrome (BOS) subtype or restrictive allograft syndrome (RAS) subtype of CLAD or risk of developing BOS subtype or RAS subtype CLAD post-transplant, the method comprising: a. measuring a normalized expression level of an RNA transcript of IL-6 or an expression product thereof in a sample of the donor lung pre-transplant or a normalized expression level of one or more S100 protein, optionally S100A8 and/or S100A9, polypeptide expression product in a sample from the donor lung post-transplant; b. assessing the likelihood of the donor lung developing BOS subtype CLAD or RAS subtype CLAD post-transplant based on said IL-6, S100, optionally S100A8 and/or S100A9, expression level wherein IL-6 expression level is positively correlated with an increased likelihood of developing BOS post-transplant, S100A8 expression level is positively correlated with having or having an increased likelihood of developing RAS and/or BOS subtype CLAD, and S100A9 is positively correlated with having and having an increased likelihood of developing RAS subtype CLAD.