T lymphocytes and Its Subsets in Transplanted Small Bowel Treated with Alemtuzumab (Campath-1H)

摘要

Alemtuzumab is a potent immunosuppressive that targets CD52 protein found on lymphocytes. We investigated the effect of alemtuzumab on T-lymphocytes (T cells) and its subsets in transplanted small bowel tissue. Immunohistochemistry was performed on transplanted small bowel collected on various post-transplant dates for 5 subjects. T cells were identified as CD3+, regulatory T cells (Tregs) were identified as CD3+FoxP3+, memory T cells were identified as CD3+CD45RO+, and naive T cells were identified as CD3+CD45RA+ cells. We also stained for CD52+ cells. T cells including memory and naive cells, as well as CD52+ cells were identified in tissue as early as 8 days after transplant. CD3+FoxP3+ cells were identified as early as 2 weeks post transplant. Ranges for absolute lymphocyte count are 0.05-9.23 in peripheral blood. There were no episodes of rejection. Despite low lymphocyte counts in peripheral blood, there were a considerable number of T-cells present in the allo-graft. Implications for graft viability and rejection are unclear.