E-rosette inhibitory factor in sera from patients with mycosis fungoides.

Peripheral blood lymphocytes from some of patients with mycosis fungoides disease showed decreased ability to form rosettes with sheep erythrocytes. This decreased percentage of E-rosette forming cells could be normalized when those cells were incubated in culture for 20 hr. Since these data led us to considering a possible inhibitory factor present in patients' sera, we tested their ability to inhibit E-rosetting by T lymphocytes from normal donors, and found that sera from mycosis fungoides patients with low levels of E-rosetting blood lymphocytes showed greater inhibitory effect on E-rosette formation by normal T cells when compared to those either from normal donors or from mycosis patients who had almost normal levels of E-rosetting blood lymphocyte number. The E-rosette inhibitory factor was sensitive to 2-mercaptoethanol treatment and was copurified with serum IgM by ammonium sulfate precipitation and by sequential gel filtrations, suggesting that it might be an anti-T lymphocyte antibody naturally occurring during the disease process.