Immune status of free-ranging green turtles with fibropapillomatosis from Hawaii

Cell-mediated and humoral immune status of free-ranging green turtles (Chel onia,mydas) in Hawaii (USA) with and without fibropapillomatosis (FP) were assessed. Tumored and non-tumored turtles from Kaneohe Bay (KB) on the isla nd of Oahu and from FP-free areas on the west (Kona/Kohala) coast of the is land of Hawaii were sampled from April 1998 through February 1999. Turtles on Oahu were grouped (0-3) for severity of tumors with 0 for absence of tum ors, 1 for light, 2 for moderate, and 3 for most severe. Turtles were weigh ed, straight carapace length measured and the regression slope of weight to straight carapace length compared between groups (KB0, KB1, KB2, KB3, Kona ). Blood was assayed for differential white blood cell count, hematocrit, i n vitro peripheral blood mononuclear cell (PBMC) proliferation in the prese nce of concanavalin A (Con-A) and phytohaemagglutinin (PHA), and protein el ectrophoresis. On Oahu, heterophil/lymphocyte ratio increased while eosinop hil/monacyte ratio decreased with increasing tumors score. Peripheral blood mononuclear cell proliferation indices for ConA and PRA were significantly lower for turtles with tumor scores 2 and 3. Tumor score 3 turtles (KB3) h ad significantly lower hematocrit, total protein, alpha 1, alpha 2, and gam ma globulins than the other four groups. No significant differences in immu ne status were seen between non-tumored (or KB1.) turtles from Oahu and Haw aii. There was no significant difference between groups in regression slope s of body condition to carapace length. We conclude that turtles with sever e FP are imunosuppressed. Furthermore, the lack of significant difference i n immune status between non-tumored (and KB1) turtles from Oahu and Kona/Ko hala indicates that immunosuppression may not be a prerequisite for develop ment of FP.