Specific T-cell responses to aspergillus fumigatus antigens

Invasive Aspergillosis is still a life-threatening infection in patients undergoing allogeneic stem cell transplantation (SCT). There is a growing body of evidence that T-cells play a major role in the immunological response to Aspergillus, and therefore, could be a potential therapeutic target in Aspergillosis. We performed a ³H-thymidine lymphoproliferation assay using different potential antigens of Aspergillus fumigatus. In order to generate Aspergillus-specific T-cells, the antigens with the highest proliferation indices (EC-SAB and 90 kDa catalase) were then used to stimulate 1.0×10⁸ mononuclear cells from healthy donors overnight. On the following day, the activated T-cells were isolated with the interferon-γ secretion assay (Miltenyi Biotec, Germany) and expanded for 13 days. Intracellular cytokine analysis of EC-SAB generated cell lines (n=3) revealed a specific interferon-γ secretion of 12.43%±4.60 of CD4⁺ cells, whereas 90 kDa catalase generated cell lines were not informative. These preliminary results might help in generating Aspergillus-specific T-cells which could be a possible option in prophylaxis and therapy of Aspergillus in patients after allogeneic SCT.