Biomedical subjects

I Jolanda M de Vries

Publications and source records attributed to I Jolanda M de Vries.

15 recordsLinked to original sources

PubMed2007

Sensitivity of magnetic resonance imaging of dendritic cells for in vivo tracking of cellular cancer vaccines.

Success of immunotherapy with dendritic cells (DC) to treat cancer is highly dependent on their interaction with and activation of antigen specific T cells. To maximize DC-T cell contact accurate delivery of the therapeutic cells into the lymph node, or efficient trafficking of DC to the lymph nodes of the patient is essential. Since responses are seen in some patients but not in others, monitoring of the injected cells may be of major importance. Tracking of cells with magnetic resonance (MR) imaging is a non-invasive method that provides detailed anatomical information and is therefore more informative for the evaluation of the localization of therapeutic cells after injection than e.g. scintigraphic imaging. To challenge the sensitivity of this novel technique, we investigated the minimum amount of label and the number of cells required for MR imaging and the effect of labeling on DC function. DC were labeled with different concentrations of a clinically approved MR contrast agent consisting of superparamagnetic iron oxide particles and were imaged at both 3 and 7 T. Our results demonstrate the following: (i) When loaded with 30 (+/-4) pg Fe/cell, cell numbers as low as 1,000 cells/mm3 at 3 T and 500 cells/mm3 at 7 T could be readily imaged; (ii) Labeling does not affect cell viability and function; (iii) Because of its high spatial resolution and sensitivity, MRI is ideally suited to track therapeutic cells in vivo.

Cancer Vaccines↗

PubMed2007

Cancer-germline gene expression in pediatric solid tumors using quantitative real-time PCR.

Cancer-germline genes (CGGs) code for immunogenic antigens that are present on various human tumors but not on normal tissues. The importance of CGGs in cancer immunotherapy has led to detailed studies of their expression in a range of human tumors. We measured the levels of expression of 12 CGGs in various pediatric solid tumors to identify targets for therapeutic cancer vaccines. Quantitative real-time PCR (qPCR) was used to measure the expression of 8 MAGE genes and of genes LAGE-2/NY-ESO-1 and GAGE-1, 2, 8 in 9 osteosarcomas, 10 neuroblastomas, 12 rhabdomyosarcomas and 18 Ewing's sarcomas. Nine tumors were also examined by immunohistochemistry with monoclonal antibodies specific for the MAGE-A1, MAGE-A4 and NY-ESO-1 proteins. All osteosarcoma and 80% of neuroblastoma samples expressed several CGGs at high levels. Six of 12 rhabdomyosarcomas and 11 of 18 Ewing's sarcomas expressed at least one CGG. Immunohistochemistry data correlated well with qPCR results and showed a homogeneous protein distribution pattern in most positive tumors. No correlation was found between the levels of CGG expression in the tumors and clinicopathological parameters of the patients. Pediatric solid tumors express several CGGs, which encode antigens that could be targeted in therapeutic vaccination trials. Several CGGs of the MAGE, GAGE and LAGE families are coexpressed in a large proportion of osteosarcoma and neuroblastoma samples. Some rhabdomyosarcomas express several of these genes at high levels. Ewing's sarcomas have an overall low CGG expression.

Adolescent↗

PubMed2006

Relevance of DC-SIGN in DC-induced T cell proliferation.

The role of dendritic cell-specific ICAM-3-grabbing nonintegrin (DC-SIGN) in DC-T cell communication was assessed by analyzing the effect of DC-SIGN-blocking mAb in MLR. The results show that the degree of inhibition by DC-SIGN and LFA-1 mAb depends on the magnitude of the MLR and the maturation status of the DC. Addition of DC-SIGN mAb at several time-points during MLR showed that DC-SIGN is involved early on in DC-T cell contacts. This initial role is masked by strong adhesive and costimulatory mechanisms, indicating a short-lived effect of DC-SIGN in DC-T cell interactions. To examine this concept in more detail, the percentage of PBL capable of binding DC-SIGN was determined. Analysis of several donors revealed that 1-20% PBL bind to beads coated with recombinant DC-SIGN, and the DC-SIGN-binding cells comprised all major cell subsets found in blood. PBL isolated from a donor with high DC-SIGN-binding capacity were more prone to blocking by DC-SIGN mAb in MLR than PBL from a donor with low DC-SIGN-binding capacity. This study indicates an initial and transient role for DC-SIGN in T cell proliferation, which becomes apparent when T cell proliferation is low and when the percentage of DC-SIGN binding PBL is high.

Antibodies, Monoclonal↗

PubMed2006

Plasmacytoid dendritic cells of melanoma patients present exogenous proteins to CD4+ T cells after Fc gamma RII-mediated uptake.

Plasmacytoid dendritic cells (pDCs) contribute to innate antiviral immune responses by producing type I interferons. Although human pDCs can induce T cell responses upon viral infection, it remains unclear if pDCs can present exogenous antigens. Here, we show that human pDCs exploit FcgammaRII (CD32) to internalize antigen-antibody complexes, resulting in the presentation of exogenous antigen to T cells. pDCs isolated from melanoma patients vaccinated with autologous monocyte-derived peptide- and keyhold limpet hemocyanin (KLH)-loaded dendritic cells, but not from nonvaccinated patients or patients that lack a humoral response against KLH, were able to stimulate KLH-specific T cell proliferation. Interestingly, we observed that internalization of KLH by pDCs depended on the presence of serum from vaccinated patients that developed an anti-KLH antibody response. Anti-CD32 antibodies inhibited antigen uptake and presentation, demonstrating that circulating anti-KLH antibodies binding to CD32 mediate KLH internalization. We conclude that CD32 is an antigen uptake receptor on pDCs and that antigen presentation by pDCs is of particular relevance when circulating antibodies are present. Antigen presentation by pDCs may thus modulate the strength and quality of the secondary phase of an immune response.

Antigen Presentation↗

PubMed2006

Development of 111In-labeled tumor-associated antigen peptides for monitoring dendritic-cell-based vaccination.

UNLABELLED: Dendritic cells (DC) are professional antigen-presenting cells capable of inducing potent immune responses. In our ongoing clinical trials, human leukocyte antigen (HLA)-A2.1+ melanoma patients are vaccinated with mature DC, presenting tumor-derived peptides in major histocompatibility complexes (MHC) to naive T cells. Previously, we have shown that both intradermally and intranodally injected (111)In-labeled mature DC migrate to draining lymph nodes. However, little is known about the fate of the MHC-peptide complex after injection of these peptide-loaded DC. The aim of the present study was to develop radiolabeled, tumor-derived peptides to monitor their binding to MHC Class I. METHODS: The HLA-A2.1 binding peptide gp100:154-162mod (gp100:154m) was conjugated with diethylenetriamine pentaacetic acid (DTPA) either at the N-terminus (alpha-DTPA-gp100:154m) or at the epsilon amino group of the Lys(154) residue (epsilon-DTPA-gp100:154m) and labeled with (111)In. RESULTS: The maximum specific activity for both peptides was 13 GBq/micromol. The IC50 of the alpha-[(111)In]DTPA-gp100:154m peptide was >75 microM. The IC50 of the (111)In-labeled epsilon-DTPA-gp100:154m was 3 microM, similar to the unconjugated peptide. MHC binding studies showed specific binding of the epsilon-[(111)In]DTPA-gp100:154m peptide to the JY cells at 4 degrees C. Interestingly, no specific binding was observed for the alpha-[(111)In]DTPA-gp100:154m peptide. In contrast to the alpha-[(111)In]DTPA-gp100:154m peptide, the epsilon-[(111)In]DTPA-gp100:154m peptide was recognized by cytotoxic T cells. CONCLUSION: When DTPA was conjugated to the epsilon NH2 group of the Lys(154) residue, MHC binding of the peptide was preserved and could still be recognized by cytotoxic T cells. These studies allow the noninvasive determination of the behavior of MHC-peptide complexes on DC in vivo.

Antineoplastic Agents↗

PubMed2005

Magnetic resonance tracking of dendritic cells in melanoma patients for monitoring of cellular therapy.

The success of cellular therapies will depend in part on accurate delivery of cells to target organs. In dendritic cell therapy, in particular, delivery and subsequent migration of cells to regional lymph nodes is essential for effective stimulation of the immune system. We show here that in vivo magnetic resonance tracking of magnetically labeled cells is feasible in humans for detecting very low numbers of dendritic cells in conjunction with detailed anatomical information. Autologous dendritic cells were labeled with a clinical superparamagnetic iron oxide formulation or (111)In-oxine and were co-injected intranodally in melanoma patients under ultrasound guidance. In contrast to scintigraphic imaging, magnetic resonance imaging (MRI) allowed assessment of the accuracy of dendritic cell delivery and of inter- and intra-nodal cell migration patterns. MRI cell tracking using iron oxides appears clinically safe and well suited to monitor cellular therapy in humans.

Cell Movement↗

PubMed2005

Immunomonitoring tumor-specific T cells in delayed-type hypersensitivity skin biopsies after dendritic cell vaccination correlates with clinical outcome.

PURPOSE: Tumor-specific immunomonitoring is essential to evaluate the efficacy of vaccination against cancer. In this study, we investigated the predictive value of the presence or absence of antigen-specific T cells in biopsies from delayed-type hypersensitivity (DTH) sites. PATIENTS AND METHODS: In our ongoing clinical trials, HLA-A2.1+ melanoma patients were vaccinated with mature dendritic cells (DC) pulsed with melanoma-associated peptides (gp100 and tyrosinase) and keyhole limpet hemocyanin. RESULTS: After intradermal administration of a DTH challenge with gp100- and tyrosinase peptide-loaded DC, essentially all patients showed a positive induration. In clinically responding patients, T cells specific for the antigen preferentially accumulated in the DTH site, as visualized by in situ tetramer staining. Furthermore, significant numbers of functional gp100 and tyrosinase tetramer-positive T cells could be isolated from these DTH biopsies, in accordance with the applied antigen in the DTH challenge. We observed a direct correlation between the presence of DC vaccine-related T cells in the DTH biopsies of stage IV melanoma patients and a positive clinical outcome (P = .0012). CONCLUSION: These findings demonstrate the potency of this novel approach in the monitoring of vaccination studies in cancer patients.

Adjuvants, Immunologic↗

PubMed2005

Effective induction of naive and recall T-cell responses by targeting antigen to human dendritic cells via a humanized anti-DC-SIGN antibody.

Current dendritic cell (DC)-based vaccines are based on ex vivo-generated autologous DCs loaded with antigen prior to readministration into patients. A more direct and less laborious strategy is to target antigens to DCs in vivo via specific surface receptors. Therefore, we developed a humanized antibody, hD1V1G2/G4 (hD1), directed against the C-type lectin DC-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) to explore its capacity to serve as a target receptor for vaccination purposes. hD1 was cross-linked to a model antigen, keyhole limpet hemocyanin (KLH). We observed that the chimeric antibody-protein complex (hD1-KLH) bound specifically to DC-SIGN and was rapidly internalized and translocated to the lysosomal compartment. To determine the targeting efficiency of hD1-KLH, monocyte-derived DCs and peripheral blood lymphocytes (PBLs) were obtained from patients who had previously been vaccinated with KLH-pulsed DCs. Autologous DCs pulsed with hD1-KLH induced proliferation of patient PBLs at a 100-fold lower concentration than KLH-pulsed DCs. In addition, hD1-KLH-targeted DCs induced proliferation of naive T cells recognizing KLH epitopes in the context of major histocompatibility complex (MHC) classes I and II. We conclude that antibody-mediated targeting of antigen to DCs via DC-SIGN effectively induces antigen-specific naive as well as recall T-cell responses. This identifies DC-SIGN as a promising target molecule for DC-based vaccination strategies.

Antibodies↗

PubMed2005

Intratumoral recombinant human interleukin-12 administration in head and neck squamous cell carcinoma patients modifies locoregional lymph node architecture and induces natural killer cell infiltration in the primary tumor.

The objective of this study was to evaluate the histologic and immunohistopathologic effects of intratumorally given recombinant human interleukin-12 on the immune cells in the primary tumors and regional lymph nodes. Ten previously untreated patients with head and neck squamous cell carcinoma (HNSCC) were injected in the primary tumor twice to thrice, once weekly, at two dose levels of 100 or 300 ng/kg, before surgery. These patients were compared with 20 non-IL-12-treated control HNSCC patients. In the primary tumor, the number of CD56+ natural killer (NK) cells was increased in IL-12-treated patients compared with control patients. In some IL-12-treated patients, an impressive peritumoral invasion of CD20+ B cells was noticed. No differences were seen in the CD8+ or CD4+ T lymphocytes. Interestingly, major differences were apparent in the architecture of the enlarged lymph nodes of IL-12-treated patients; in particular, the distribution of B cells differed and fewer primary and secondary follicles with smaller germinal centers were observed. In addition, a decrease of dendritic cell lysosyme-associated membrane glycoprotein-positive cells in the paracortex was noted, resulting in a reduction of paracortical hyperplasia. In the lymph nodes, especially the CD56+ NK cells but also the CD8+ and CD4+ T lymphocytes, produced a high amount of IFN-gamma. Patients, irrespectively of IL-12 treatment, with a high number of CD56+ cells in the primary tumor had a better overall survival than those with a low number. In conclusion, after i.t. IL-12 treatment in HNSCC patients, the largest effect was seen on the NK cells, with a higher number in the primary tumor and a high IFN-gamma mRNA expression in the lymph nodes. Significant effects were noted on B cells, with altered lymph node architecture in every IL-12-treated patient and excessive peritumoral infiltration in some patients.

Adjuvants, Immunologic↗

PubMed2005

Migration of dendritic cell based cancer vaccines: in vivo veritas?

Ex vivo generated cancer vaccines based on dendritic cells (DCs) are currently applied in the clinic. The migration of DCs from the tissues to the lymph nodes is tightly controlled and involves many different mediators and their receptors. A recent study demonstrated that the rate of migration of antigen-bearing DCs in situ from the skin to the lymph node is 100-fold higher than previously estimated. The migration of ex vivo generated DCs is rather inefficient but can be improved by pre-conditioning of the vaccine injection site with inflammatory cytokines. An alternative approach that is currently being explored is to target tumor antigens directly to DCs in situ, thereby exploiting the intricate migratory capacity of DCs in vivo. Recent advances have been made in understanding DC migration in the context of DC-based vaccines.

Animals↗

PubMed2005

Phenotypical and functional characterization of clinical-grade dendritic cells.

Dendritic cells (DC) are the most potent antigen-presenting cells and form a promising new treatment modality. Fully activated DC loaded with antigen are very useful in stimulating immune responses, in particular those to combat cancer. Immature DC can either cause immunological tolerance or induce regulatory T-cells, opening up future application in transplantation, autoimmunity, and perhaps chronic inflammation. For these clinical applications, generation of DC under Good Manufacturing Practice conditions and without the use of animal products is a main prerequisite. To date, there are many different DC culture protocols, which subsequently lead to different types of DC. Protocols differ not only in DC preparation techniques, but also many other variables, like maturation status, dose and timing interval, route of administration, and antigen loading. DC vaccination, although very promising, is far from standardized. In this chapter we discuss the usefulness of standardized clinical and immunological criteria and the need for careful study design to further optimize the use of dendritic cells and to unequivocally prove their efficacy.

Cell Differentiation↗

PubMed2004

Dendritic cell immunotherapy: mapping the way.

Dendritic cells (DCs) are the professional antigen-presenting cells of the immune system, with the potential to either stimulate or inhibit immune responses. Exploiting the immune-regulatory capacities of dendritic cells holds great promise for the treatment of cancer, autoimmune diseases and the prevention of transplant rejection. Although early clinical trials indicate that DC vaccines can induce immune responses in some cancer patients, careful study design and use of standardized clinical and immunological criteria are needed.

Animals↗

PubMed2003

Maturation of dendritic cells is a prerequisite for inducing immune responses in advanced melanoma patients.

PURPOSE: We have investigated the capacity of immature and mature monocyte-derived DCs pulsed with melanoma-associated peptides (gp100 and tyrosinase) to induce a primary cytotoxic T-lymphocyte response in vivo. EXPERIMENTAL DESIGN: Advanced HLA-A2.1(+) melanoma patients were vaccinated with peptide- and keyhole limpet hemocyanin (KLH)-pulsed DCs, either immature (9 patients) or matured by monocyte-conditioned medium/tumor necrosis factor alpha/prostaglandin E(2) (10 patients). RESULTS: All patients vaccinated with mature DCs showed a pronounced proliferative T-cell and humoral response against KLH. By contrast, KLH responses were absent in most of the patients vaccinated with immature DCs. Delayed-type hypersensitivity (DTH) reactions against antigen-pulsed DCs were only observed in patients vaccinated with mature DCs and not in patients vaccinated with immature DCs. MHC-peptide tetramer staining of DTH-derived T cells revealed the presence of specific T cells recognizing the melanoma-associated peptides in 1 patient. In a second patient, DTH-derived T cells showed specific lysis of tumor cells expressing the antigens used for DC pulsing. Only patients vaccinated with mature DCs showed objective clinical responses. Interestingly, both patients with long-term progression-free survival (22 and >40 months) were both vaccinated with mature DCs and demonstrated antigen-specific T-cell reactivity of DTH-derived T cells. CONCLUSIONS: We conclude that mature DC are superior to immature DC in the induction of immunological responses in melanoma patients, which may translate into improved clinical results.

Adjuvants, Immunologic↗

PubMedDate not supplied

Phenotypical and functional characterization of clinical grade dendritic cells.

Dendritic cells (DC) are the professional antigen presenting cells of the immune system. Therefore, several clinical studies have been initiated in which tumor antigen-loaded DC are used as a vaccine to boost an immune response against malignant tumors in patients with cancer. A prerequisite for DC used in these vaccination studies is not only that they are grown under "Good Manufacturing Practice" but equally important that they retain their functional properties. In an extensive study, various conditions were tested to optimize the maturation and yield of DC grown for clinical use. DC grown in XVIVO-15 medium supplemented with 5% HS yielded the best results, morphologically and phenotypically. Mature DC expressed significant amounts of mature DC markers (CD83) and the costimulatory molecules CD80 and CD86. It was shown that mature and immature DC can be frozen and retain their phenotype and function after thawing. These clinical grade DC secreted high levels of the chemokines dendritic cell chemokine 1 (DC-CK1), interleukin-8 (IL-8), macrophage-derived chemokine (MDC), and thymus and activation-regulated chemokine (TARC). This implicates that these DC can attract naïve T and B cells as well as natural killer cells and memory T cells. Finally, to test their migratory capacity in vivo, (111)In-labeled DC were injected into tumor-free lymph nodes of patients with melanoma. Autoradiographic analysis of the dissected lymph nodes indicated that these DC could migrate into the T cell area of adjacent lymph nodes. In conclusion, a culture procedure was established to generate large numbers of monocyte-derived immature and mature DC that retain their morphologic, phenotypic, and functional characteristics in vitro and can be visualized in situ.

Cancer Vaccines↗

PubMedDate not supplied

Vaccination of patients with metastatic renal cell carcinoma with autologous dendritic cells pulsed with autologous tumor antigens in combination with interleukin-2: a phase 1 study.

Dendritic cells (DC) have been recognized as the most potent antigen presenting cells (APC) of the immune system. We performed a phase 1 study in twelve patients with metastatic renal cell carcinoma (RCC) using autologous immature DC loaded with autologous tumorlysate (TuLy) as a vaccine based on our earlier in vitro observations that such DC can activate tumor-specific cytotoxic T-lymphocytes. The treatment was combined with low-dose interleukin (IL)-2, as this has shown benefit in DC-based therapies. Patients received three intradermal vaccinations at two weekly intervals, and, after each vaccination, IL-2 was administered for 5 consecutive days. In six patients, keyhole-limpet hemocyanin (KLH) was added to the DC culture for immunologic monitoring purposes. In general, DC phenotype was CD14(low), CD86(high), CD40(high), CD80(low), and CD83(low). We noticed that the number of CD14+ cultured DC increased during treatment. Nevertheless, ovalbumin uptake remained high, underlining that these cells were still functional immature DC. The vaccine was able to elicit cellular anti-KLH responses, emphasizing the ability of the injected DC to mount an immunologic response. However, proliferative responses against TuLy were not detected, and humoral responses against TuLy or KLH were absent. Objective clinical responses were not observed, but extended stable disease was noted. The absence of cellular, humoral, or clinical antitumor responses suggests that the vaccination strategy with immature DC has little benefit for patients with advanced RCC. Nevertheless, this study shows the feasibility of a completely autologous DC and tissue culture methodology for the generation of TuLy pulsed DC.

Adjuvants, Immunologic↗