Functional IgG Autoantibodies against Autonomic Nervous System Receptors in Symptomatic Women with Silicone Breast Implants.

The association between the clinical picture of symptomatic women with silicone breast implants (SBI) and dysregulated immunity was in dispute for decades. In the current study, we describe for the first time the functional activity of purified IgG antibodies derived from symptomatic women with SBIs (suffering from subjective/autonomic-related symptoms), both in vitro and in vivo. We found that IgGs, derived from symptomatic women with SBIs, dysregulate inflammatory cytokines (TNFα, IL-6) in activated human peripheral blood mononuclear cells, compared to healthy-women-derived IgGs. Importantly, behavioral studies conducted following intracerebroventricular injection of IgGs derived from symptomatic women with SBIs (who have dysregulated circulating level of IgG autoantibodies directed against autonomic nervous system receptors) into mice brains demonstrated a specific and transient significant increment (about 60%) in the time spent at the center of the open field arena compared with mice injected with IgG from healthy women (without SBIs). This effect was accompanied with a strong trend of reduction of the locomotor activity of the SBI-IgG treated mice, indicating an overall apathic-like behavior. Our study is the first to show the potential pathogenic activity of IgG autoantibodies in symptomatic women with SBIs, emphasizing the importance of these antibodies in SBI-related illness.

Soluble HLA peptidome of pleural effusions is a valuable source for tumor antigens.

BACKGROUND: Soluble human leucocyte antigen (sHLA) molecules, released into the plasma, carry their original peptide cargo and provide insight into the protein synthesis and degradation schemes of their source cells and tissues. Other body fluids, such as pleural effusions, may also contain sHLA-peptide complexes, and can potentially serve as a source of tumor antigens since these fluids are drained from the tumor microenvironment. We explored this possibility by developing a methodology for purifying and analyzing large pleural effusion sHLA class I peptidomes of patients with malignancies or benign diseases. METHODS: Cleared pleural fluids, cell pellets present in the pleural effusions, and the primary tumor cells cultured from cancer patients' effusions, were used for immunoaffinity purification of the HLA molecules. The recovered HLA peptides were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) and the resulting LC-MS/MS data were analyzed with the MaxQuant software tool. Selected tumor antigen peptides were tested for their immunogenicity potential with donor peripheral blood mononuclear cells (PBMCs) in an in vitro assay. RESULTS: Mass spectrometry analysis of the pleural effusions revealed 39,669 peptides attributable to 11,305 source proteins. The majority of peptides identified from the pleural effusions were defined as HLA ligands that fit the patients' HLA consensus sequence motifs. The membranal and soluble HLA peptidomes of each individual patient correlated to each other. Additionally, soluble HLA peptidomes from the same patient, obtained at different visits to the clinic, were highly similar. Compared with benign effusions, the soluble HLA peptidomes of malignant pleural effusions were larger and included HLA peptides derived from known tumor-associated antigens, including cancer/testis antigens, lung-related proteins, and vascular endothelial growth factor pathway proteins. Selected tumor-associated antigens that were identified by the immunopeptidomics were able to successfully prime CD8+ T cells. CONCLUSIONS: Pleural effusions contain sHLA-peptide complexes, and the pleural effusion HLA peptidome of patients with malignant tumors can serve as a rich source of biomarkers for tumor diagnosis and potential candidates for personalized immunotherapy.

Mesencephalic astrocyte-derived neurotrophic factor is secreted from interferon-γ-activated tumor cells through ER calcium depletion.

The most successful immunotherapeutic agents are blocking antibodies to either programmed cell death-1 (PD-1), an inhibitory receptor expressed on T lymphocytes, or to its ligand, programmed cell death-ligand 1 (PD-L1). Nevertheless, many patients do not respond, and additional approaches, specifically blocking other inhibitory receptors on T cells, are being explored. Importantly, the source of the ligands for these receptors are often the tumor cells. Indeed, cancer cells express high levels of PD-L1 upon stimulation with interferon-γ (IFN-γ), a major cytokine in the tumor microenvironment. The increase in PD-L1 expression serves as a negative feedback towards the immune system, and allows the tumor to evade the attack of immune cells. A potential novel immunoregulator is mesencephalic astrocyte-derived neurotrophic factor (MANF), an endoplasmic reticulum (ER)-resident protein that is secreted from pancreatic beta cells upon cytokines activation, and can induce an alternatively activated macrophage phenotype (M2), and thus may support tumor growth. While MANF was shown to be secreted from pancreatic beta cells, its IFN-γ-induced secretion from tumor cells has never been assessed. Here we found that IFN-γ induced MANF secretion from diverse tumor cell-lines-melanoma cells, colon carcinoma cells and hepatoma cells. Mechanistically, there was no increase in MANF RNA or intracellular protein levels upon IFN-γ stimulation. However, IFN-γ induced ER calcium depletion, which was necessary for MANF secretion, as Dantrolene, an inhibitor of ER calcium release, prevented its secretion. Thus, MANF is secreted from IFN-γ-stimulated tumor cells, and further studies are required to assess its potential as a drug target for cancer immunotherapy.

Photodynamic effect of novel hexa-iodinated quinono-cyanine dye on Staphylococcus aureus.

BACKGROUND: Staphylococcus aureus (S. aureus) is a Gram-positive bacteria and major human pathogen which can cause a wide variety of serious infections when it enters the bloodstream or internal tissues. Antimicrobial photodynamic therapy (APDT) utilizing a light-activated dye (photosensitizer) is a powerful method for in vitro and in vivo eradication of S. aureus and other pathogenic bacteria. However, the development of highly efficient, long-wavelength photosensitizers showing high phototoxicity to pathogens and low dark toxicity is still challenging. AIM: To develop a highly efficient, long-wavelength photosensitizer for photodynamic inactivation of S. aureus. METHOD: Synthesis of the new photosensitizer, hexa-iodinated quinono-cyanine dye IQCy and investigation of the dark and light-induced toxicity of this dye compared to known photosensitizers Chlorin e6 (Ce6) and HITC towards S. aureus. RESULTS: When exposed to 14.9 J/cm2 white LED light, 0.5 µM of IQCy, Ce6 and HITC inactivate, respectively, 99 %, 40 % and 30 % of S. aureus and at 0.05 µM and 27.9 J/cm2 - 71 %, 18 % and 9%, which is much better compared to Ce6 and HITC. IQCy exhibits no dark toxicity at least at 10 µM dye concentration. CONCLUSIONS: IQCy demonstrates a more pronounced photodynamic inactivation of S. aureus as compared to Ce6 and HITC and can be employed for the eradication of these bacteria at lower concentration and reduced light dose.