Biomedical subjects

Joseph Fay

Publications and source records attributed to Joseph Fay.

12 recordsLinked to original sources

PubMed2005

Immunotherapy via dendritic cells.

The immune system evolved to protect us from microbes. The antigen (Ag)-nonspecific innate immunity and Ag-specific adaptive immunity synergize to eradicate the invading pathogen through cells, such as dendritic cells (DCZ7) and lymphocytes, and through their effector proteins including antimicrobial peptides, complement, and antibodies. Its intrinsic complexity renders the immune system prone to dysfunction including cancer, autoimmunity, chronic inflammation and allergy. DCs are unique in their capacity to induce and regulate immune responses and are therefore attractive candidates for immunotherapy. However, DCs consist of distinct subsets with common as well as unique functions that lead to distinct types of immune responses. Therefore, understanding DC heterogeneity and their role in immunopathology is critical to design better strategies for immunotherapy. Indeed, what we learn from studying autoimmunity will help us induce strong vaccine specific immunity, either protective, as in the case of microbes, or therapeutic, as in the case of tumors.

Animals↗

PubMed2005

Spontaneous proliferation and type 2 cytokine secretion by CD4+T cells in patients with metastatic melanoma vaccinated with antigen-pulsed dendritic cells.

We observed the induction of spontaneous, i.e., without adding exogenous antigen, in vitro proliferation of PBMCs from patients with stage IV melanoma who underwent repeated vaccinations with antigen-loaded dendritic cells (DCs) derived from CD34(+) hematopoietic progenitors (CD34-DCs). Proliferating cells are CD4(+)T cells. Their proliferation is dependent on (1) CD11c(+) myeloid DCs, since their depletion from PBMCs abolishes it; and (2) IL-2, as it can be blocked by neutralizing anti-IL-2 antibodies. Spontaneous proliferation is associated to the secretion of type 2 cytokines. To analyze the frequency of spontaneous proliferation induction in the cohort of 18 vaccinated patients, an index of spontaneous proliferation was defined as a ratio of PBMCs proliferation from post- vs pre-DC vaccination blood samples. Ten out of sixteen analyzed patients showed an index > 2. The index of spontaneous proliferation correlates with antigen-specific PBMC proliferation to the vaccine antigen KLH. Furthermore, both spontaneous- and antigen-specific proliferation in PBMC cultures are dependent on blood myeloid DCs.

Antigen Presentation↗

PubMed2004

Expansion of melanoma-specific cytolytic CD8+ T cell precursors in patients with metastatic melanoma vaccinated with CD34+ progenitor-derived dendritic cells.

Cancer vaccines aim at inducing (a) tumor-specific effector T cells able to reduce/eliminate the tumor mass, and (b) long-lasting tumor-specific memory T cells able to control tumor relapse. We have shown earlier, in 18 human histocompatibility leukocyte antigen (HLA)-A*0201 patients with metastatic melanoma, that vaccination with peptide-loaded CD34-dendritic cells (DCs) leads to expansion of melanoma-specific interferon gamma-producing CD8+ T cells in the blood. Here, we show in 9 out of 12 analyzed patients the expansion of cytolytic CD8+ T cell precursors specific for melanoma differentiation antigens. These precursors yield, upon single restimulation with melanoma peptide-pulsed DCs, cytotoxic T lymphocytes (CTLs) able to kill melanoma cells. Melanoma-specific CTLs can be grown in vitro and can be detected in three assays: (a) melanoma tetramer binding, (b) killing of melanoma peptide-pulsed T2 cells, and (c) killing of HLA-A*0201 melanoma cells. The cytolytic activity of expanded CTLs correlates with the frequency of melanoma tetramer binding CD8+ T cells. Thus, CD34-DC vaccines can expand melanoma-specific CTL precursors that can kill melanoma antigen-expressing targets. These results justify the design of larger follow-up studies to assess the immunological and clinical response to peptide-pulsed CD34-DC vaccines.

Antigens, CD34↗

PubMed2003

Dendritic cells as vectors for immunotherapy of cancer.

Dendritic cells (DCs) initiate and regulate immune responses. Numerous studies in mice showed that tumor antigens-loaded DCs are able to induce therapeutic and protective anti-tumor immunity. The immunogenicity of antigens delivered on DCs has now been demonstrated in cancer patients and some clinical responses without any significant toxicity have been observed. Nevertheless, many parameters of DC vaccination need to be established including: (1) the type of DCs, their maturation stage and stimuli; (2) the quality and the breadth of induced immune responses; (3) host-related factors, such as the extent of metastatic disease and myeloablation; and (4) efficacy as measured by the clinical outcome.

Animals↗

PubMed2003

Recombinant human thrombopoietin augments mobilization of peripheral blood progenitor cells for autologous transplantation.

This study assessed the ability of various schedules of recombinant human thrombopoietin (rhTPO) to enhance mobilization of peripheral blood progenitor cells (PBPCs) in 134 patients with cancer undergoing high-dose chemotherapy and autologous PBPC transplantation. Patients received the study drug on days 1, 3, and 5 before initiation of granulocyte colony-stimulating factor (G-CSF) 10 microg/kg/day on day 5 and pheresis starting on day 9. Randomly assigned treatments on days 1, 3, and 5 were: group 1 (n=27) placebo, placebo, rhTPO 1.5 microg/kg; group 2 (n=27) rhTPO 1.5 microg/kg, placebo, placebo; groups 3 (n=28) and 4 (n=22) rhTPO 0.5 microg/kg on all 3 treatment days; and group 5 (n=30) placebo on all 3 treatment days. After high-dose chemotherapy and PBPC transplantation, groups 1 through 4 received rhTPO 1.5 microg/kg days 0, +2, +4, and +6 with either G-CSF 5 microg/kg/day (groups 1-3) or granulocyte-macrophage colony-stimulating factor 250 microg/m(2)/day (group 4). Group 5 received placebo plus G-CSF 5 microg/kg/day. The addition of rhTPO to G-CSF increased median CD34+ cell yield/pheresis in cohorts in which rhTPO was started before day 5, with higher yields in groups 2 (2.67 x 10(6)/kg) and groups 3 and 4 (3.10 x 10(6)/kg) than in group 1 (1.86 x 10(6)/kg) or group 5 (1.65 x 10(6)/kg) (P=.006 across groups). Comparing rhTPO to placebo, higher percentages of patients achieved the minimum yield of CD34+ > or =2 x 10(6)/kg (92% v 75%; P=.050) as well as the target yield of CD34+ > or =5 x 10(6)/kg (73% v 46%; P= .041). rhTPO-treated patients required fewer phereses to achieve minimum (P= .011) and target (P= .015) CD34+ cell values. rhTPO given after transplantation did not speed platelet recovery. No neutralizing antibodies were observed. We conclude that rhTPO can safely enhance mobilization of PBPC, reduce the number of leukapheresis, and allow more patients to meet minimal cell yield requirements to receive high-dose chemotherapy with PBPC transplantation.

Adult↗

PubMed2003

Dendritic cells: controllers of the immune system and a new promise for immunotherapy.

The immune system is controlled by dendritic cells (DCs). Just as lymphocytes comprise different subsets, DCs comprise several subsets that differentially control lymphocyte function. In humans, the myeloid pathway includes Langerhans cells (LCs) and interstitial DCs (intDCs). While both subsets produce IL-12, only intDCs make IL-10 and induce B cell differentiation. Another pathway includes plasmacytoid DCs, which promptly secrete large amounts of IFN-alpha/beta viral encounter. Thus, insights into in vivo DC functions are important to understand the launching and modulation of immunity.

Dendritic Cells↗

PubMed2003

Dendritic cells: controllers of the immune system and a new promise for immunotherapy.

Dendritic cells (DCs) can be utilized either as vectors or as targets for therapy. Patients with metastatic melanoma received CD34-DC vaccine that contains Langerhans' cells and interstitial DCs. DCs were pulsed with MART1, tyrosinase, MAGE3, gp100 and Flu-MP peptides, and KLH. DCs induced an immune response to control antigens in 16/18 patients. An enhanced immune response to 1 or more melanoma antigens (MelAgs) was seen in these 16 patients. The two patients failing to respond experienced rapid tumour progression. Six out of seven patients with immunity to two or fewer MelAgs had progressive disease 10 weeks after study entry, in contrast to tumour progression in only 1/10 patients with immunity to > two MelAgs. Since tumour immunotherapy targets autologous antigens we can learn from systemic autoimmunity such as systemic lupus erythematosus (SLE). As opposed to normal monocytes, SLE monocytes induce proliferation of allogeneic CD4+ T cells. SLE sera induce monocyte differentiation towards DCs in an IFNalpha-dependent mechanism. Spiking autologous serum with IFNalpha reproduces DC differentiation. 50% of SLE patients have high serum levels of IFNalpha, which could explain T/B lymphopenia. Yet, plasmacytoid DCs, a major IFNalpha source, are 80% decreased. pDCs and IFNalpha may play a role in SLE pathogenesis and therapy.

Animals↗

PubMedDate not supplied

Single injection of CD34+ progenitor-derived dendritic cell vaccine can lead to induction of T-cell immunity in patients with stage IV melanoma.

There is evidence that dendritic cell (DC) vaccines induce tumor-specific immune responses that correlate with clinical responses. Little is known, however, about the kinetics of T-cell responses to antigens presented on DC vaccines. The authors vaccinated 18 HLA A*0201+ patients with stage IV melanoma with CD34 HPC-derived DCs pulsed with six antigens: influenza matrix peptide (Flu-MP), KLH, and peptides derived from the four melanoma antigens: MART-1/Melan A, gp100, tyrosinase, and MAGE-3. A single DC vaccination was sufficient for induction of KLH-specific CD4 T-cell responses in five patients and Flu-MP-specific CD8 T-cell responses in eight patients. A single DC vaccine was sufficient for induction of tumor-specific effectors to at least one melanoma antigen in five patients. Thus, a single injection of CD34 HPC-derived DCs can lead to rapid immune response to CD4 epitopes or to melanoma antigens.

Adolescent↗

PubMedDate not supplied

Measuring melanoma-specific cytotoxic T lymphocytes elicited by dendritic cell vaccines with a tumor inhibition assay in vitro.

Improving cancer vaccines depends on assays measuring elicited tumor-specific T-cell immunity. Cytotoxic effector cells are essential for tumor clearance and are commonly evaluated using 51Cr release from labeled target cells after a short (4 hours) incubation with T cells. The authors used a tumor inhibition assay (TIA) that assesses the capacity of cytotoxic T lymphocytes (CTLs) to control the survival/growth of EGFP-labeled tumor cell lines. TIA was validated using CD8+ T cells primed in vitro against melanoma and breast cancer cells. TIA was then used to assess the CTL function of cultured CD8+ T cells isolated from patients with metastatic melanoma who underwent vaccination with peptide-pulsed CD34+ HPCs-derived DCs. After the DC vaccination, T cells from six of eight patients yielded CTLs that could inhibit the survival/growth of melanoma cells. The results of TIA correlated with killing of tumor cells in a standard 4-hour 51Cr release assay, yet TIA allowed detection of CTL activities that appeared marginal in the 51Cr release assay. Thus, TIA might prove valuable for measuring spontaneous and induced antigen-specific cytotoxic T cells.

Antigens, CD34↗

PubMedDate not supplied

Boosting vaccinations with peptide-pulsed CD34+ progenitor-derived dendritic cells can expand long-lived melanoma peptide-specific CD8+ T cells in patients with metastatic melanoma.

The immunogenicity of dendritic cell (DC)-based vaccines has been shown in patients with advanced cancer, but it has not yet been established whether the elicited cancer-specific immunity is durable and whether it can be maintained by boosting vaccinations. The authors showed earlier, in 18 HLA-A*0201 metastatic melanoma patients, that four vaccinations over 6 weeks with peptide-loaded CD34-DCs (the induction phase) expand in the blood melanoma-specific CD8+ T cells, as documented by melanoma peptide-specific IFN-gamma ELISPOT and cytotoxic T-lymphocyte (CTL) activity against melanoma cell lines. The authors show here that the melanoma peptide-specific CD8+ T-cell immunity is short-lived, but it could be reactivated in 7 of 11 patients who received four boosting vaccinations with peptide-loaded CD34-DCs. Expansion of recall memory CD8+ T cells was confirmed by tetramer binding and CTL activity against melanoma peptide-pulsed T2 cells. In two patients boosted over 15 months, induced melanoma peptide-specific recall memory CD8+ T cells lasted at least 6 months. Thus, boosting vaccination with peptide-loaded CD34-DCs can expand long-lived tumor peptide-specific immunity.

Antigens, CD34↗

PubMedDate not supplied

Immune and clinical outcomes in patients with stage IV melanoma vaccinated with peptide-pulsed dendritic cells derived from CD34+ progenitors and activated with type I interferon.

Twenty-two HLA A*0201 patients with stage IV melanoma were enrolled in a phase 1 safety and feasibility trial using a composite dendritic cell (DC) vaccine generated by culturing CD34 hematopoietic progenitors and activated with IFN-alpha. The DC vaccine was loaded with peptides derived from four melanoma tissue differentiation antigens (MART-1, tyrosinase, MAGE-3, and gp100) and influenza matrix peptide (Flu-MP). Twenty patients were evaluable, 14 of whom received vaccination with peptide-pulsed DCs without keyhole limpet hemocyanin (KLH) and 6 of whom received vaccination with KLH-loaded DCs. Patients were vaccinated until disease progression or until they had received eight vaccinations. None of the analyzed patients showed the expansion of melanoma-peptide-specific circulating effector memory T cells that secrete IFN-gamma in direct ELISPOT. Melanoma-peptide-specific recall memory CD8 T cells able to secrete IFN-gamma and to proliferate could be detected in six of the seven analyzed patients. There were no objective clinical responses. The estimated median overall survival was 12 months (range 2-38), and the median event-free survival was 4 months (range 1-12). There was no statistically significant survival advantage in patients who received KLH-loaded vaccines. As of March 2005, four patients remained alive, 26+, 28+, 28+, and 36+ months. Three of them had received KLH-loaded vaccines and all of them had had additional therapy. Overall, these results suggest that IFN-alpha-activated CD34-DCs are safe but elicit only limited immune responses, underscoring the need to test different DC maturation factors.

Adult↗

PubMedDate not supplied

Dendritic cells loaded with killed allogeneic melanoma cells can induce objective clinical responses and MART-1 specific CD8+ T-cell immunity.

Dendritic cells (DCs) loaded with killed allogeneic tumors can cross-prime tumor-specific naive CD8 T cells in vitro, thereby providing an option to overcome human leukocyte antigen restriction inherent to loading DC vaccines with peptides. We have vaccinated 20 patients with stage IV melanoma with autologous monocyte-derived DCs loaded with killed allogeneic Colo829 melanoma cell line. DCs were generated by culturing monocytes with granulocyte macrophage-colony stimulating factor (granulocyte macrophage-colony stimulating factor) and interleukin (IL-4) and activated by additional culture with tumor necrosis factor and CD40 ligand. A total of 8 vaccines were administered at monthly intervals. The first patient was accrued December 2002 and the last November 2003. Fourteen patients were alive at 12 months, 9 patients were alive at 24 months, and 8 patients are alive as of January 2006. The estimated median overall survival is 22.5 months with a range of 2 to 35.5 months. Vaccinations were safe and tolerable. They induced, in 2 patients who failed previous therapy, durable objective clinical responses, 1 complete regression (CR) and 1 partial regression (PR) lasting 18 and 23 months, respectively. Three out of 13 analyzed patients showed T-cell immunity to melanoma antigen recognized by autologous T cells (MART-1) tissue differentiation antigen. Two of 3 patients showed improved immune function after vaccinations demonstrated by improved secretion of interferon (IFN)-gamma or T-cell proliferation in response to MART-1 derived peptides. In one of these patients, vaccination led to elicitation of CD8 T-cell immunity specific to a novel peptide-derived from MART-1 antigen, suggesting that cross-priming/presentation of melanoma antigens by DC vaccine had occurred. Thus, the present results justify the design of larger follow-up studies to assess the clinical response to DC vaccines loaded with killed allogeneic tumor cells in patients with metastatic melanoma.

Adult↗