1. Consequences of the photodynamic treatment of resting and activated peripheral T lymphocytes
- Author
-
Agnes H. Chan, David J. Granville, Huijun Jiang, Simon Leong, Julia G. Levy, and David W. C. Hunt
- Subjects
Male ,Porphyrins ,CD3 Complex ,Receptors, Antigen, T-Cell, alpha-beta ,T-Lymphocytes ,T cell ,Apoptosis ,Biology ,Lymphocyte Activation ,Antibodies ,Mice ,Interleukin 21 ,medicine ,Animals ,Cytotoxic T cell ,IL-2 receptor ,Interphase ,Pharmacology ,Photosensitizing Agents ,ZAP70 ,Verteporfin ,CD28 ,Receptors, Interleukin-2 ,DNA ,Natural killer T cell ,Molecular biology ,medicine.anatomical_structure ,Mice, Inbred DBA ,Immunology ,Cell Division ,CD8 - Abstract
The impact of the immunomodulatory photosensitizer benzoporphyrin derivative monoacid ring A (BPD-MA, verteporfin) and visible light on the survival and surface receptor pattern of resting and activated murine T cells was evaluated. T cells treated for 48 h with immobilized anti-CD3 monoclonal antibody upregulated expression of the interleukin-2 receptor alpha-chain (CD25), transferrin receptor (CD71), the apoptosis-regulating Fas receptor (CD95), contained a greater level of the anti-apoptotic protein Bcl-2 and accumulated significantly more BPD-MA than their unactivated counterparts. Activated T cells displayed a modestly greater susceptibility to the photodynamic induction of DNA fragmentation than resting T cells. Resting T cells treated with sub-lethal levels of BPD-MA and light did not exhibit changes in surface levels of CD3, CD4, CD8, CD28, CD45 or T cell receptor (TCR) beta-chain structures. However, levels of major histocompatibility complex (MHC) class I antigens were decreased while the density of Thy-1.2 (CD90) increased on these cells. Photodynamically treated T cells failed to express optimal CD25 levels when exposed to the mitogenic anti-CD3 antibody. Activated T cells treated with sub-lethal levels of BPD-MA and light exhibited lower CD25 levels, a temporary block in cell cycle transition, but unaltered expression of MHC Class I, CD3, CD4, CD8, CD45, CD54, CD71, CD122 (IL-2R beta-chain) or TCR beta-chain antigens 24 h afterward. Resting and activated T lymphocytes differ in susceptibility to PDT-mediated apoptosis but both types are sensitive to anti-proliferative effects the treatment exerts at sub-lethal photosensitizer levels. The marked sensitivity of activated T cells to photodynamic inactivation likely contributes to the immunomodulatory action of BPD-MA.
- Published
- 1999