Quantitative studies on biological water oxidation: a novel mechanism of T cells and antibodies.

Prior studies show that purified T cell receptors (TCRs) and antibodies catalyze the oxidation of water to H2O2 in the presence of singlet oxygen, but the comparative efficiencies of TCRs and antibodies in this process have not been reported. Since H2O2 has been shown to activate TCRs and selectively regulate redox sensitive TCR signaling pathways, it is important to understand the physiological significance of these recently uncovered processes. This new information might be used to develop new therapeutic tools for immune and inflammatory diseases.

Biophotonic hydrogen peroxide production by antibodies, T cells, and T-cell membranes.

Rapidly accumulating evidence indicates that inflammatory T cells sensitively respond to their redox environment by activating signal transduction pathways. The hypothesis that T-cell receptors have the potential to catalytically transform singlet oxygen into H(2)O(2) attracted our attention since the biophysical regulation of this process would provide a new tool for therapeutically directing T cells down a preferred signaling pathway. Light-dependent production of H(2)O(2) was first described in antibodies, and we reproduced these findings.

A photochemical microreactor used to analyze hydrogen peroxide (H2O2) production of T lymphocytes.

In this report we describe a new photochemical reactor and its use in the study of ultraviolet-B light (UVB) dependent H2O2 production by T lymphocytes. In the reactor multiple biological samples rotate around a luminescent tube and thus simultaneously absorb a uniform light-flux. The reactor was developed to expand our earlier studies where we showed that UVB activates T lymphocytes so that 10(7) cells produce about 60 nmol H2O2 per minute.

Characterization of a real time H2O2 monitor for use in studies on H2O2 production by antibodies and cells.

It was recently shown that antibodies catalyze a reaction between water and ultraviolet light (UV) creating singlet oxygen and ultimately H2O2. Although the in vivo relevance of these antibody reactions is unclear, it is interesting that among a wide variety of non-antibody proteins tested, the T cell receptor is the only protein with similar capabilities. In clinical settings UV is believed to exert therapeutic effects by eliminating inflammatory epidermal T cells and we hypothesized that UV-triggered H2O2 production is involved in this process.

Use of proteomics methodology to evaluate inflammatory protein expression in tendinitis.

In previous studies we established a rat model of acute tendinitis including functional and mechanical measures of healing. Achilles' tendinitis was induced by injection of collagenase, an enzyme that produces localized fiber digestion and edema formation. As quantitative measures of tissue inflammation, hypercellularity and edema were evaluated in injured tendons in comparison with controls.

Effect of short duration electromagnetic field exposures on rat mass.

Daily preexposure and postexposure mass measurements of 65 rats (young males and females, old males) a proprietary pulsed wound healing field, pulsed electromagnetic field, (PEMF), or their control fields for 4 h/day for 21 days. Statistical analysis of mass changes over time showed that young rats exposed to PEMF lost more mass and recovered it more slowly compared to controls (2-4% more loss) than did older PEMF exposed rats or any 60 Hz exposed rats. We conclude that daily preexposure and postexposure mass measurements are needed to adequately assess the effects of electromagnetic fields on body mass.