Michela Spadaro

Bio: Michela Spadaro is an academic researcher from University of Turin. The author has contributed to research in topics: Immune system & CD8. The author has an hindex of 18, co-authored 34 publications receiving 1273 citations.

Electroporated DNA vaccine clears away multifocal mammary carcinomas in her-2/neu transgenic mice.

Abstract: The transforming rat Her-2/neu oncogene embedded into the genome of virgin transgenic BALB/c mice (BALB-neuT) provokes the development of an invasive carcinoma in each of their 10 mammary glands. i.m. vaccination with DNA plasmids coding for the extracellular and transmembrane domains of the protein product of the Her-2/neu oncogene started when mice already display multifocal in situ carcinomas temporarily halts neoplastic progression, but all mice develop a tumor by week 43. By contrast, progressive clearance of neoplastic lesions and complete protection of all 1-year-old mice are achieved when the same plasmids are electroporated at 10-week intervals. Pathological findings, in vitro tests, and the results from the immunization of both IFN-gamma and immunoglobulin gene knockout BALB-neuT mice, and of adoptive transfer experiments, all suggest that tumor clearance rests on the combination of antibodies and IFN-gamma-releasing T cells. These findings show that an appropriate vaccine effectively inhibits the progression of multifocal preneoplastic lesions.

Oral lactoferrin inhibits growth of established tumors and potentiates conventional chemotherapy

Abstract: In this work, we investigated the anticancer activity of orally administered recombinant human lactoferrin (rhLF) alone and in combination with chemotherapy in tumor-bearing mice rhLF inhibited the growth of squamous cell carcinoma (O12) tumors in T cell-immunocompromised nu/nu mice by 80% when administered at 1,000 mg/kg (29 g/m2) by oral gavage twice daily for 8 days (p < 0001) Similar activity was observed in syngeneic, immunocompetent BALB/c mice, where orally administered rhLF (1,000 mg/kg, 29 g/m2 once daily) halted the growth of mammary adenocarcinoma TUBO Oral rhLF (200 mg/kg, 057 g/m2) was also used alone and in combination with cis-platinum (5 mg/kg) to treat head-and-neck squamous cell carcinoma in a syngeneic murine model Monotherapy with oral rhLF or cis-platinum caused 61% or 66% tumor growth inhibition over placebo, respectively Mice receiving both therapies showed 79% growth inhibition, a statistically significant improvement over each drug alone We then demonstrated that administration of oral rhLF (300 mg/kg, 086 g/m2) to tumor-bearing or naive mice resulted in (i) significantly increased production of IL-18 in the intestinal tract, (ii) systemic NK cell activation and (iii) circulating CD8+ T-cell expansion These data suggest that oral rhLF is an immunomodulatory agent active against cancer as a single agent and in combination chemotherapy, exerting its systemic effect through stimulation of IL-18 and other cytokines in the gut enterocytes rhLF has been administered orally to 211 people without a single serious drug-related adverse event Thus, rhLF shows promise as a safe and well-tolerated novel immunomodulatory anticancer agent

Nonredundant roles of antibody, cytokines, and perforin in the eradication of established Her-2/neu carcinomas

Abstract: Since the mechanisms by which specific immunity destroys Her-2/neu carcinoma cells are highly undetermined, these were assessed in BALB/c mice vaccinated with plasmids encoding extracellular and transmembrane domains of the protein product (p185neu) of the rat Her-2/neu oncogene shot into the skin by gene gun. Vaccinated mice rejected a lethal challenge of TUBO carcinoma cells expressing p185neu. Depletion of CD4 T cells during immunization abolished the protection, while depletion of CD8 cells during the effector phase halved it, and depletion of polymorphonuclear granulocytes abolished all protection. By contrast, Ig μ-chain gene KO mice, as well as Fcγ receptor I/III, β-2 microglobulin, CD1, monocyte chemoattractant protein 1 (MCP1), IFN-γ, and perforin gene KO mice were protected. Only mice with both IFN-γ and perforin gene KOs were not protected. Although immunization also cured all BALB/c mice bearing established TUBO carcinomas, it did not cure any of the perforin KO or perforin and IFN-γ KO mice. Few mice were cured that had knockouts of the gene for Ig μ-chain, Fcγ receptor I/III, IFN-γ, or β-2 microglobulin. Moreover, vaccination cured half of the CD1 and the majority of the MCP1 KO mice. The eradication of established p185neu carcinomas involves distinct mechanisms, each endowed with a different curative potential.

Lactoferrin, a major defense protein of innate immunity, is a novel maturation factor for human dendritic cells

Abstract: Lactoferrin (LF) is an important protein component of the innate immune system that is broadly distributed within the body fluids. LF is endowed with multiple biological activities. Talactoferrin (TLF), a recombinant human LF, is in clinical development as an anticancer agent and is entering Phase III clinical trials. Here, we show that TLF induces the maturation of human dendritic cells (DCs) derived from monocytes. TLF, at physiologically relevant concentrations (100 microg/ml) up-regulates the expression of human leukocyte antigen (HLA) class II, CD83, CD80, and CD86 costimulatory molecule and CXCR4 and CCR7 chemokine receptors, acting primarily through the p38 MAPK signaling pathway. DCs matured by TLF displayed an enhanced release of IL-8 and CXCL10, as well as a significantly reduced production of IL-6, IL-10, and CCL20. They also display a reduced ability to take up antigen and increased capacity to trigger proliferation and release IFN-gamma in the presence of allogeneic human T cells. TLF-matured DCs are able to prime naive T cells to respond to KLH antigen and display a significantly increased capacity to present Flu-MA(58-66) peptide to HLA-A2-matched T cells. These data suggest that a key immunomodulatory function that may be mediated by TLF is to link the innate with adaptive immunity through DC maturation.

Immunosurveillance of Erbb2 Carcinogenesis in Transgenic Mice Is Concealed by a Dominant Regulatory T-Cell Self-Tolerance

Abstract: To assess the role of CD4(+)CD25(+)Foxp3(+) regulatory T (Treg) cells in overcoming immunosurveillance of Erbb2 (HER-2/neu) mammary lesions, we studied the effects of their sustained removal in BALB/c female mice made transgenic for the rat Erbb2 (r-Erbb2) oncogene (BALB-neuT mice), which develop multiple mammary carcinomas. During the progression of these lesions, Treg cells expand in the spleen, tumor draining lymph nodes, and tumors. Repeated administration of anti-CD25 antibodies extends tumor-free survival, reduces carcinoma multiplicity, and leads to the manifestation of a natural antibody and CTL-mediated reactivity against r-Erbb2. Loss of Foxp3(+) Treg cells during anti-CD25 treatment remarkably caused the disappearance of Gr1(+) immature myeloid cells, suggesting a cross-talk between these two inhibitory immune cell types. Treg cell expansion associated with r-Erbb2 overexpression may be seen as a physiologic response to dampen the immune reaction elicited by local anomalous overexpression of a self-antigen.

Cytokines in cancer pathogenesis and cancer therapy

Abstract: The mixture of cytokines that is produced in the tumour microenvironment has an important role in cancer pathogenesis. Cytokines that are released in response to infection, inflammation and immunity can function to inhibit tumour development and progression. Alternatively, cancer cells can respond to host-derived cytokines that promote growth, attenuate apoptosis and facilitate invasion and metastasis. A more detailed understanding of cytokine–tumour-cell interactions provides new opportunities for improving cancer immunotherapy.

Systemic spread is an early step in breast cancer.

Abstract: It is widely accepted that metastasis is a late event in cancer progression. Here, however, we show that tumor cells can disseminate systemically from earliest epithelial alterations in HER-2 and PyMT transgenic mice and from ductal carcinoma in situ in women. Wild-type mice transplanted with single premalignant HER-2 transgenic glands displayed disseminated tumor cells and micrometastasis in bone marrow and lungs. The number of disseminated cancer cells and their karyotypic abnormalities were similar for small and large tumors in patients and mouse models. When activated by bone marrow transplantation into wild-type recipients, 80 early-disseminated cancer cells sufficed to induce lethal carcinosis. Therefore, release from dormancy of early-disseminated cancer cells may frequently account for metachronous metastasis.

DNA vaccines: ready for prime time?

Abstract: Since the discovery, over a decade and a half ago, that genetically engineered DNA can be delivered in vaccine form and elicit an immune response, there has been much progress in understanding the basic biology of this platform. A large amount of data has been generated in preclinical model systems, and more sustained cellular responses and more consistent antibody responses are being observed in the clinic. Four DNA vaccine products have recently been approved, all in the area of veterinary medicine. These results suggest a productive future for this technology as more optimized constructs, better trial designs and improved platforms are being brought into the clinic.

Chemical exchange saturation transfer (CEST): what is in a name and what isn't?

Abstract: Chemical exchange saturation transfer (CEST) imaging is a relatively new magnetic resonance imaging contrast approach in which exogenous or endogenous compounds containing either exchangeable protons or exchangeable molecules are selectively saturated and after transfer of this saturation, detected indirectly through the water signal with enhanced sensitivity. The focus of this review is on basic magnetic resonance principles underlying CEST and similarities to and differences with conventional magnetization transfer contrast. In CEST magnetic resonance imaging, transfer of magnetization is studied in mobile compounds instead of semisolids. Similar to magnetization transfer contrast, CEST has contributions of both chemical exchange and dipolar cross-relaxation, but the latter can often be neglected if exchange is fast. Contrary to magnetization transfer contrast, CEST imaging requires sufficiently slow exchange on the magnetic resonance time scale to allow selective irradiation of the protons of interest. As a consequence, magnetic labeling is not limited to radio-frequency saturation but can be expanded with slower frequency-selective approaches such as inversion, gradient dephasing and frequency labeling. The basic theory, design criteria, and experimental issues for exchange transfer imaging are discussed. A new classification for CEST agents based on exchange type is proposed. The potential of this young field is discussed, especially with respect to in vivo application and translation to humans.

Cancer Immunosurveillance and Immunoediting: The Roles of Immunity in Suppressing Tumor Development and Shaping Tumor Immunogenicity

Abstract: Cellular transformation and tumor development result from an accumulation of mutational and epigenetic changes that alter normal cell growth and survival pathways. For the last 100 years, there has been a vigorous debate as to whether the unmanipulated immune system can detect and eliminate such altered host derived cells despite the fact that cancer cells frequently express either abnormal proteins or abnormal levels of normal cellular proteins that function as tumor antigens. In this review, we discuss the current state of this argument and point out some of the recent key experiments demonstrating that immunity not only protects the host from cancer development (i.e., provides a cancer immunosurveillance function) but also can promote tumor growth, sometimes by generating more aggressive tumors. The terminology "cancer immunoediting" has been used to describe this dual host protective and tumor promoting action of immunity, and herein we summarize the ever-increasing experimental and clinical data that support the validity of this concept.