Prospects for the Use of Metal-Based Nanoparticles as Adjuvants for Local Cancer Immunotherapy

Immunotherapy is among the most effective approaches for treating cancer. One of the key aspects for successful immunotherapy is to achieve a strong and stable antitumor immune response. Modern immune checkpoint therapy demonstrates that cancer can be defeated. However, it also points out the weaknesses of immunotherapy, as not all tumors respond to therapy and the co-administration of different immunomodulators may be severely limited due to their systemic toxicity. Nevertheless, there is an established way through which to increase the immunogenicity of immunotherapy-by the use of adjuvants. These enhance the immune response without inducing such severe adverse effects. One of the most well-known and studied adjuvant strategies to improve immunotherapy efficacy is the use of metal-based compounds, in more modern implementation-metal-based nanoparticles (MNPs), which are exogenous agents that act as danger signals. Adding innate immune activation to the main action of an immunomodulator makes it capable of eliciting a robust anti-cancer immune response. The use of an adjuvant has the peculiarity of a local administration of the drug, which positively affects its safety. In this review, we will consider the use of MNPs as low-toxicity adjuvants for cancer immunotherapy, which could provide an abscopal effect when administered locally.

Immunological status of chronically exposed persons with increased level of TCR mutations

Dose- and dose rate-dependent increase in the number of СD3⁺СD16⁺CD56⁺-lymphocytes and lysosomal activity of neutrophils was noted in peripheral blood of the Techa riverside residents with increased level of TCR gene-mutated T lymphocytes long after chronic exposure of predominantly red bone marrow (mean exposure dose was 0.89 ± 0.09 Gy, individual dose range was 0.09-1.96 Gy). The performed analysis showed that the above-mentioned immunological changes could be a response to an increase in the frequency of mutations (TCR mutations in particular) in the cells of exposed individuals.

PECULIARITIES OF DYNAMICS OF PERIPHERAL BLOOD CELL COMPOSITION IN CHRONICALLY-EXPOSED INDIVIDUALS IN THE PERIOD PRIOR TO LEUKEMIA DEVELOPMENT

A retrospective analysis of the peripheral blood cell composition (PBCC) has been performed among 43 chronically-exposed Techa riverside residents later diagnosed with chronic myeloid leukemia (CML) or acute leukemias (AL). Prior to CML development, a significant increase in peripheral blood neutrophil count has been noted in exposed individuals for many years. Neutrophil count grew most significantly after reduction of exposure dose rate to red bone marrow (RBM) to ≤0.1 Gy, which was typical both for CML and AL. An increase of a relative neutrophil count remained in the CML latency period along with relative lymphocytopenia. Peculiarities of PBCC among individuals with AL at a later date were 'rejuvenation' of neutrophils in the period of maximum exposure and in leukemia latency period. During haematopoiesis restoration period, high mean values of mature neutrophils were detected in the majority of exposed individuals with AL together with decreased lymphocyte and eosinophil count. Later higher mean values of neutrophils remained in these individuals.

Unsolvable Problems of Biology: It Is Impossible to Create Two Identical Organisms, to Defeat Cancer, or to Map Organisms onto Their Genomes

The review is devoted to unsolvable problems of biology. 1) Problems unsolvable due to stochastic mutations occurring during DNA replication that make it impossible to create two identical organisms or even two identical complex cells (Sverdlov, E. D. (2009) Biochemistry (Moscow), 74, 939-944) and to "defeat" cancer. 2) Problems unsolvable due to multiple interactions in complex systems leading to the appearance of unpredictable emergent properties that prevent establishment of unambiguous relationships between the genetic architecture and phenotypic manifestation of the genome and make impossible to predict with certainty responses of the organism, its parts, or pathological processes to external factors. 3) Problems unsolvable because of the uncertainty principle and observer effect in biology, due to which it is impossible to obtain adequate information about cells in their tissue microenvironment by isolating and analyzing individual cells. In particular, we cannot draw conclusions on the properties of stem cells in their niches based on the properties of stem cell cultures. A strategy is proposed for constructing the pattern most closely approximated to the relationship of genotypes with their phenotypes by designing networks of intermediate phenotypes (endophenotypes).