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K D Beckman

Publications and source records attributed to K D Beckman.

3 recordsLinked to original sources
PubMed1984

Characterization of two suppressor cells that together prevent in vivo development of cytolytic T cells to hapten-altered self.

Two suppressor cell populations that interact to down-regulate in vivo development of the cytolytic T-cell (CTL) response to trinitrophenyl-modified syngeneic spleen cells (TNP-SC) have been further characterized. Suppressor cells induced by the iv injection of trinitrophenyl-modified syngeneic spleen cells possess Thy 1.2 antigen. Their precursors are insensitive to pretreatment of host animals with cyclophosphamide (CY). Suppressor cells that arise after dermal sensitization with trinitrochlorobenzene are also Thy 1.2 antigen positive but their precursors are sensitive to pretreatment with CY. These characteristics of the two suppressor T cells (Ts) are identical to those of the two Ts that are generated by similar methodologies and that together suppress contact sensitivity (CS) to picryl chloride. Neither the CS nor CTL response was suppressed when host animals possessed only one set of Ts. In contrast to suppression of CS at the efferent phase, development of CTL was suppressed only when the two Ts were present early during sensitization (afferent phase). Since the results point to several similarities between the two sets of Ts that are active in the down-regulation of the CS and CTL responses, it is suggested that the two dissimilar immune responses directed to the same hapten, namely CS and CTL, may be controlled by the same suppressor cells. Since it appears that the two sets of Ts interact to affect different phases of the CS and CTL responses, down-regulation of each must be accomplished through different mechanisms.

Animals↗
PubMed1983

Two distinct suppressor T cells acting in concert cause suppression of cytolytic T lymphocyte (CTL) response to hapten-altered self in vivo.

The participation of two subpopulations of suppressor T cells (Ts) active in the suppression of hapten-specific contact sensitivity (CS) was investigated in the down-regulation of in vivo development of CTL to hapten-altered self. We have shown that Ts efferent (Ts-eff) cell that is induced by tolerizing mice with an i.v. injection of hapten-coupled syngeneic spleen cells, and the auxiliary Ts cell (Ts-aux), which is generated by dermal application of hapten, together suppress the generation of CTL. Thus, when tolerant mice possessing Ts-eff cells were concomitantly sensitized for CTL and CS (which causes the arisal of Ts-aux and TDTH effector cells), the development of CTL was suppressed. Furthermore, adoptive transfer of lymph node cells from dermally sensitized mice into tolerant mice also suppressed the CTL response. Use of lymph node cells from mice pretreated with cyclophosphamide before dermal sensitization and therefore lacking Ts-aux cells was not efficient in suppressing the CTL response. Thus, neither Ts-eff alone nor TDTH in conjunction with Ts-aux were capable of suppressing the development of CTL. In addition to supporting the view that the in vivo generation of CTL is suppressed when both Ts-eff and Ts-aux cells are present, the data indicate that suppressor cells operational for one T cell-mediated response (CS) are equally functional for a separate unrelated one (CTL).

Animals↗