Targeted Delivery of HSP70 to Tumor Cells via Supramolecular Complex Based on HER2-Specific DARPin9_29 and the Barnase:Barstar Pair

(1) Background: We have previously shown that the use of an artificial supramolecular two-component system based on chimeric recombinant proteins 4D5scFv-barnase and barstar-heat shock protein 70 KDa (HSP70) allows targeted delivery of HSP70 to the surface of tumor cells bearing HER2/neu antigen. In this work, we studied the possibility to using DARPin9_29-barnase as the first targeting module recognizing HER2/neu-antigen in the HSP70 delivery system. (2) Methods: The effect of the developed systems for HSP70 delivery to human carcinomas SK-BR-3 and BT474 cells hyperexpressing HER2/neu on the activation of cytotoxic effectors of the immune cells was studied in vitro. (3) Results: The results obtained by confocal microscopy and cytofluorimetric analysis confirmed the binding of HSP70 or its fragment HSP70-16 on the surface of the treated cells. In response to the delivery of HSP70 to tumor cells, we observed an increase in the cytolytic activity of different cytotoxic effector immune cells from human peripheral blood. (4) Conclusions: Targeted modification of the tumor cell surface with molecular structures recognized by cytotoxic effectors of the immune system is among new promising approaches to antitumor immunotherapy

Reduced Immunosenescence of Peripheral Blood T Cells in Parkinson’s Disease with CMV Infection Background

Immunosenescence is a process of remodeling the immune system under the influence of chronic inflammation during aging. Parkinson’s disease (PD) is a common age-associated neurodegenerative disorder and is frequently accompanied by neuroinflammation. On the other hand, cytomegalovirus (CMV), one of the most spread infections in humans, may induce chronic inflammation which contributes to immunosenescence, differentiation and the inflation of T cells and NK cells. Currently, there is no clear understanding of immunosenescence severity in PD patients infected with CMV. In this study, we analyzed differentiation stages and immunosenescence characteristics of T cells and NK cells in 31 patients with mild and moderate PD severity, 33 age-matched and 30 young healthy donors. The PD patients were 100% CMV-seropositive compared to 76% age-matched and 73% young CMV-infected healthy donors. The proportion of effector memory T cells re-expressing CD45RA, CD57+CD56− T cells and CD57+CD56+ T cells was significantly reduced in PD patients compared with CMV-seropositive age-matched healthy individuals. The CD57+CD56− T cell proportion in PD patients was similar to that of CMV-seropositive young healthy donors. Thus, PD is characterized by reduced peripheral blood T cell immunosenescence, even against the background of CMV infection

Increased Susceptibility of the CD57⁻ NK Cells Expressing KIR2DL2/3 and NKG2C to iCasp9 Gene Retroviral Transduction and the Relationships with Proliferative Potential, Activation Degree, and Death Induction Response

Nowadays, the use of genetically modified NK cells is a promising strategy for cancer immunotherapy. The additional insertion of genes capable of inducing cell suicide allows for the timely elimination of the modified NK cells. Different subsets of the heterogenic NK cell population may differ in proliferative potential, in susceptibility to genetic viral transduction, and to the subsequent induction of cell death. The CD57−NKG2C+ NK cells are of special interest as potential candidates for therapeutic usage due to their high proliferative potential and certain features of adaptive NK cells. In this study, CD57− NK cell subsets differing in KIR2DL2/3 and NKG2C expression were transduced with the iCasp9 suicide gene. The highest transduction efficacy was observed in the KIR2DL2/3+NKG2C+ NK cell subset, which demonstrated an increased proliferative potential with prolonged cultivation. The increased transduction efficiency of the cell cultures was associated with the higher expression level of the HLA-DR activation marker. Among the iCasp9-transduced subsets, KIR2DL2/3+ cells had the weakest response to the apoptosis induction by the chemical inductor of dimerization (CID). Thus, KIR2DL2/3+NKG2C+ NK cells showed an increased susceptibility to the iCasp9 retroviral transduction, which was associated with higher proliferative potential and activation status. However, the complete elimination of these cells with CID is impeded

Alterations in Proteostasis System Components in Peripheral Blood Mononuclear Cells in Parkinson Disease: Focusing on the HSP70 and p62 Levels

Parkinson disease (PD) is attributed to a proteostasis disorder mediated by α-synuclein accumulating in a specific brain region. PD manifestation is often related to extraneuronal alterations, some of which could be used as diagnostic or prognostic PD biomarkers. In this work, we studied the shifts in the expression of proteostasis-associated chaperones of the HSP70 family and autophagy-dependent p62 protein values in the peripheral blood mononuclear cells (PBMC) of mild to moderate PD patients. Although we did not detect any changes in the intracellular HSP70 protein pool in PD patients compared to non-PD controls, an increase in the transcriptional activity of the stress-associated HSPA1A/B and HSPA6 genes was observed in these cells. Basal p62 content was found to be increased in PD patients’ PBMC, similarly to the p62 level in substantia nigra neural cells in PD. Moreover, the spontaneous apoptosis level was increased among PBMC and positively correlated with the p62 intracellular level in the PD group. A combined HSPA6- and p62-based analysis among 26 PD patients and 36 age-matched non-PD controls pointed out the diagnostic significance of these markers, with intermediate sensitivity and high specificity of this combination when observing patients diagnosed with PD