For vaccination strategies and adoptive immunotherapy purposes, immature dendritic cells (DC) can be generated from adherent monocytes using GM-CSF and IL-4. Presently, the only clinically applicable method to induce stable maturation of DC is the use of supernatants of activated monocytes (monocyte-conditioned medium (MCM)). MCM contains an undefined mixture of cytokines and is difficult to standardize. Here we report that stable maturation of DC can be simply induced by the addition of polyriboinosinic polyribocytidylic acid (poly(I:C)), a synthetic dsRNA clinically applied as an immunomodulator. Poly(I:C)-treated DC show a mature phenotype with high expression levels of HLA-DR, CD86, and the DC maturation marker CD83. This mature phenotype is retained for 48 h after cytokine withdrawal. In contrast to untreated DC, poly(I:C)-treated DC down-regulate pinocytosis, produce high levels of IL-12 and low levels of IL-10, induce strong T cell proliferation in a primary allo MLR, and effectively present peptide Ags to HLA class I-restricted CTL. In conclusion, we present a simple methodology for the preparation of clinically applicable mature DC.

Recipients of HLA-identical stem cell transplants have a poorer transplant outcome if the donor is female rather than male. We analyzed whether pregnancy primes for minor histocompatibility (H) antigens. Peripheral blood mononuclear cells (PBMCs) from healthy multiparous female blood donors were depleted for CD4⁺, CD14⁺, CD16⁺, and CD19⁺ cells, stained with minor H antigen–specific HLA-A2 tetramers, sorted by fluorescence-activated cell sorting, and tested for cytotoxic activity. Minor H antigens HY-, HA-1–, and HA-2–specific cytotoxic T cells (CD8⁺, CD45RA^–) were present in PBMCs from 4 of 7 female donors up to 22 years after the last delivery. Interestingly, in 2 of the 4 cases microchimerism of the putative immunizing minor H antigen was observed. Thus, pregnancy can lead to alloimmune responses against the infant9s paternal minor H antigens. The minor H antigen immunization status of female donors raises important questions for the clinical practice of stem cell transplantation.

This review summarizes actual clinical needs in oncology that can be addressed by Raman spectroscopy, provides results published in the last 10 years and analyses the current status of translation of these results into clinical practice.