Correlation of T . bryosalmonae prevalence and cell/ antibody marker genes in rainbow trout kidney. ( A ) CD8α; ( B ) CD8ß; ( C ) IL-2Rß; ( D ) secretory IgD; ( E ) secretory IgM; ( F ) secretory IgT. Pearson correlation r coefficients are given relative to T. bryosalmonae RPL18 and kidney swelling (in parentheses). Significant correlations are shown in bold. *P < 0.05; **P < 0.01 (2-tailed).