Envision system peroxidase dab kit

From day + 1 until day + 90 after BMT, HCMV pp65 antigen monitoring was performed twice a month. From day + 90 until 6 months after BMT, the pp65 antigen assay was performed every month. At the same time, conventional methods were used to assay liver enzyme levels. Liver enzyme levels are usually less than 40 U/L for AST and less than 50 U/L for ALT. All of the patients were monitored twice weekly during the next 2 months after BMT, and then every month during the next 4 months post-6 months after BMT. A total of 296 blood samples were taken from the 30 patients. Immunohistochemistry was used to identify CMV pp65 antigen. The CMV antigen assay was performed as described previously, with minor modifications.^{11 (link),14 (link)} A standard two-step immunohistochemical method was used to assay CMV antigen expression in PBLs. In brief, leukocytes were separated from EDTA-anticoagulated blood and spread on slides. Anti-CMV-PP65-Ag monoclonal antibody (DAKO, Denmark) and the Envision™ + System peroxidase (DAB) kit (DAKO) were used. The stained samples were analysed under an optical microscope with an image recording system (BH-2, OLYMPUS, Japan). Cells that were stained yellow or brown were positive and blue cells were negative. The results are shown as the number of positive cells per 50,000 leukocytes, as previously described.^{15 (link)}