57
antibodies (a T-cell controlled event in mice) associated with the
hapten-carrier effect in mammals does not necessarily occur in fish.
However, Uhr et al. (113) demonstrated that goldfish, when acclimated to
a high temperature (35C), were capable of responding to an antigen with
both 16S and 7S antibodies (as opposed to a response at lower tempera
tures of only 16S antibodies). Though it was not proven that the 7S
antibody vas in fact a de_ novo product and not a degradation product of
the 16S antibody or a shed membrane receptor, a PHA, high temperature
responsive cell type conceivably could be functional in controlling the
switch mechanism at 35C in goldfish.
Temperature effects on lymphocytes may not be confined solely to
bluegill lymphocytes. R. C. Ashman, University of Western Australia,
Nedlands (personal communication) has demonstrated an increase in PHA
responsiveness of human T-cells when cultured at 39C rather than 37C.
Armadillos have body temperatures of < 35C, yet the transformation of
lymphocytes stimulated by PHA was increased approximately 2.6 times
when cultured at 37C rather than 33C (91). Perhaps an evaluation of
mitogenic responses of other mammalian lymphocytes cultured in narrower
temperature ranges (37  2C) is warranted. However experiments done
by J. W. Shands, Jr., University of Florida, Gainesville, Fla. (personal
communication) using mouse spleen lymphocytes cultured with LPS and PHA
at 22, 27, 32, 35, 37 and 39C showed the optimal response to both mito
gens was obtained at 37C.
The Bluegill Lymphocyte as an Experimental Model
Differential responses to mitogens by cells cultured at different
temperatures should provide a valuable method to study functional and
physiochemical properties of the cells involved in immune reactions of