IMPROVEMENT OF HOST RESPONSE TO SEPSIS BY PHOTOBIOMODULATION

Background and Objective: Late sepsis causes immunosuppression and is associated with energy depletion in lymphocytes. Adjuvant treatment wi th ATP-MgCL2 appears to improve cellular energetics and decrease morta lity. Laser irradiation can promote cell proliferation and increase ce llular ATP synthesis, which may improve the host immune response in se psis. The purpose of this study was to determine whether laser irradia tion (LII has a stimulatory effect on the immune response in sepsis us ing an animal model. Study Deisgn/Materials and Methods: The cecal lig ation and puncture (CLP) rat model was used. Thirty-six SD rats were d ivided equally among four groups: control (nonoperative), sham operati on, CLP treated with laser irradiation, and CLP without laser irradiat ion. The peritoneal cavity of each animal in CLP/laser group was irrad iated immediately after CLP using an Argon-dye laser at a wavelength o f 630 nm and at a fluence of 5 J/cm(2). Some animals were euthanized 2 4 hr following CLP and were used to evaluate the immune response (lymp hoctye proliferation). In a separate experiment, the survival of septi c rats was observed for 60 days. Lymphocytes isolated from normal rat spleens were used to observe far biostimulatory effects in vitro. Resu lts: LI significantly improved ex-vivo lymphoctye proliferation of cel ls from septic rats (179.7 +/- 17.2 vs. 129.5 +/- 7.8; P < 0.01) and e nhanced survival in septic rats (79% vs. 42%; P < 0.001). LI significa ntly stimulated lymphoctye proliferation in the presence of mitogenic stimuli and enhanced lymphoctye ATP synthesis (P < 0.05). Conclusion: LI improves the host inunune response and survival rate in sepsis in a n animal model. Our studies suggest that LI may be useful as an adjuva nt therapy for sepsis. (C) 1997 Wiley-Liss, Inc.