Anatoli Tassis

Cutaneous T-cell lymphoma (CTCL) is a lymphoproliferative skin disease with limited therapeutic options. Ten CTCL patients were treated with once-weekly intranodal injection of 1 x 106 mature monocyte-derived dendritic cells (DCs) pulsed with 100 microg/mL tumor lysate protein equivalent and keyhole limpet hemocyanin (50 microg/mL). Tumor-specific delayed-type hypersensitivity (DTH) reactions developed in 8 of 8 patients challenged with tumor-lysate-pulsed DCs and in 3 of 8 patients challenged with tumor lysate alone. Three of 5 patients showed significant tumor-lysate-specific increases of in vitro peripheral blood lymphocyte proliferation coinciding with increased interferon-alpha (IFN-alpha) production. Five of 10 (50%) patients had objective responses. Four patients had partial responses (PRs). Two are still in PR, and the other 2 patients had a mean PR duration of 10.5 months. One patient had a complete response (CR) for 19 months that is ongoing. The remaining 5 patients had progressive disease. In the 5 responder patients, 6.8 +/- 1.4 vaccinations were necessary to induce an objective clinical response. Response was associated with low tumor burden. Continuation of vaccinations with new tumor lysate derived from progressive lesions reinduced treatment responses in 2 patients in PR. Selected patients had massive infiltration of CD8+ and TIA+ cytotoxic T cells at the site of regressing lesions and molecular remission after therapy. Intranodal injection of autologous tumor-lysate-pulsed DCs is well-tolerated and achieves immunologic and objective clinical responses in selected CTCL patients.

Dendritic cells (DC) are central regulators of immunity. Signal-induced maturation of DCs is assumed to be the starting point for specific immune responses. To further understand this process, we analyzed the alteration of transcript profiles along the time course of CD40 ligand-induced maturation of human myeloid DCs by Affymetrix GeneChip microarrays covering >6800 genes. Besides rediscovery of genes already described as associated with DC maturation proving reliability of the methods used, we identified clusterin as novel maturation marker. Looking across the time course, we observed synchronized kinetics of distinct functional groups of molecules whose temporal coregulation underscores known cellular events during dendritic cell maturation. For example, an early-peaking wave of inflammatory chemokines was followed by a sustained increase of constitutive chemokines and accompanied by slow but continuous induction of survival proteins. After an immediate but transient induction of cytokine-responsive transcripts, there was an increased expression of a group of genes involved in not only the regulation of cytokine effects, but also of transcription in general. Our results demonstrate that microarray studies along time courses combined with real-time PCR not only discover new marker molecules with functional implications, but also dissect the molecular kinetics of biological processes identifying complex pathways of regulation.

Cancer/testis-antigens (CTA), a novel and expanding family of immunogenic proteins detected by serological screening of recombinant cDNA expression libraries, encompass promising candidate targets for T-cell based immunotherapy. We screened kryo-preserved tissue of cutaneous T cell lymphoma (CTCL, n=36) such as mycosis fungoides (MF, n=17), pleomorphic cutaneous T-cell lymphoma (n=8) and Sezary's syndrome (SS, n= 11) as well as a non-malignant entity (small plaques parapsoriasis, SPP, n=5), for the expression of CTA by RT-PCR and Northern blot hybridization. From a panel of eleven CTA (MAGE-1, MAGE-C1, MAGE-3, BAGE, GAGE, SSX-1, SSX-2, SSX4, SCP-1, NY-ESO-1 and TS85) (HOM-Tes-85), mRNA expression could be detected for SCP-1 in 8/17 MF and 6/8 pleomorphic CTCL patients but was completely absent in small plaques parapsoriasis. SS patients had a more heterogeneous antigen expression pattern: Gage (1/11), MAGE-1 (3/11), MAGE-3 (6/11), MAGE-C1 (5/11), NY-ESO-1 (7/11) and TS85 (5/11), with expression of MAGE-3 confirmed by immunohistochemistry. CTA could provide defined targets for antigen-based vaccination in a high percentage of cases with CTCL. SCP-1 might serve as an additional diagnostic indicator in early and clinically indistinct lesions suspicious for cutaneous T-cell lymphoma.

Cancer/testis-antigens (CTA), a novel and expanding family of immunogenic proteins detected by serological screening of recombinant cDNA expression libraries, encompass promising candidate targets for T-cell based immunotherapy. We screened kryo-preserved tissue of cutaneous T cell lymphoma (CTCL, n=36) such as mycosis fungoides (MF, n=17), pleomorphic cutaneous T-cell lymphoma (n=8) and Sezary's syndrome (SS, n= 11) as well as a non-malignant entity (small plaques parapsoriasis, SPP, n=5), for the expression of CTA by RT-PCR and Northern blot hybridization. From a panel of eleven CTA (MAGE-1, MAGE-C1, MAGE-3, BAGE, GAGE, SSX-1, SSX-2, SSX4, SCP-1, NY-ESO-1 and TS85) (HOM-Tes-85), mRNA expression could be detected for SCP-1 in 8/17 MF and 6/8 pleomorphic CTCL patients but was completely absent in small plaques parapsoriasis. SS patients had a more heterogeneous antigen expression pattern: Gage (1/11), MAGE-1 (3/11), MAGE-3 (6/11), MAGE-C1 (5/11), NY-ESO-1 (7/11) and TS85 (5/11), with expression of MAGE-3 confirmed by immunohistochemistry. CTA could provide defined targets for antigen-based vaccination in a high percentage of cases with CTCL. SCP-1 might serve as an additional diagnostic indicator in early and clinically indistinct lesions suspicious for cutaneous T-cell lymphoma. © 2001 Wiley-Liss, Inc.