Response Of Peripheral Blood Lymphocytes Research Articles

Development of High-Production Bacterial Biomimetic Vesicles for Inducing Mucosal Immunity Against Avian Pathogenic Escherichia coli

To evaluate the immunoprotective effect of bacterial biomimetic vesicles (BBVs) against avian pathogenic Escherichia coli (APEC), a ΔtolA J11 mutant strain was generated by deleting the tolA gene in the low pathogenic O78 serotype J11 strain. The total protein content of outer membrane vesicles (OMVs) derived from the ΔtolA J11 strain exhibited a sevenfold increase compared to the wild-type strain. Additionally, high-pressure homogenization technology was employed to produce BBVs, resulting in a sixfold increase in total protein content compared to spontaneously secreted OMVs from ΔtolA J11. The immunogenicity of both OMVs and BBVs was assessed through intranasal or intramuscular immunization in specific pathogen-free (SPF) chickens. Results demonstrated that intranasal immunization with OMVs or BBVs in chickens elicited specific IgY antibodies against APEC outer membrane proteins and specific sIgA antibodies in the nasal cavity and trachea, as well as a significant increase in the proliferation response of chicken peripheral blood lymphocytes. The bacterial load in the blood and various organs of the challenged chickens were significantly reduced, resulting in a 66.67% and 58.30% survival rate against a high pathogenic serotype O78 strain challenge, while the control group exhibited only a 16.67% survival rate. The intramuscular immunization with OMVs or BBVs in chickens only induced specific IgY antibodies, with a survival rate of only 33.33% for challenged chickens during the same period. Therefore, intranasal vaccination of the highly productive BBVs is capable of eliciting an immune response similar to that of OMVs and providing protection against APEC infection, thus offering innovative insights for the advancement of APEC vaccines.

Study of Radiosensitivity and Induction of Radiation Adaptive Response in Peripheral Blood Lymphocytes of Patients with Oncological Diseases Using the Micronuclear Test.

Radiosensitivity to low and medium doses of X-ray radiation and the ability to induce a radiation adaptive response (RAR) of lymphocytes during in vitro irradiation of peripheral blood of patients with cancer were studied. The criterion for cytogenetic damage was the frequency of micronuclei (MN) in cytochalasin-blocked binucleate lymphocytes in culture. It was found that the spontaneous level of cytogenetic damage in the lymphocytes of patients was 2.6 times higher than in healthy volunteers, and there was also significant interindividual variability in values compared to the control cohort. There were no differences in mean values for radiosensitivity to low and medium doses of X-ray between the study groups. There was no correlation between the spontaneous level of MN in lymphocytes and the radiosensitivity of individuals in both groups. RAR was induced with the same frequency and to the same extent in lymphocytes from both patients and healthy individuals.

Burkholderia cepacia in cystic fibrosis children and adolescents: overall survival and immune alterations.

In current literature there are only scarce data on the host inflammatory response during Burkholderia cepacia complex (Bcc) persistence. The primary objective of the present research was to carry out cross-sectional analyses of biomarkers and evaluate disease progression in cystic fibrosis (CF) patients with chronic Bcc infection and pathogen-free ones. The secondary aim was to assess prospectively overall survival of the study participants during up to 8 years of follow-up. The study included 116 paediatric patients with CF; 47 CF patients were chronically infected with Bcc, and 69 individuals were Bcc free. Plasma and sputum biomarkers (neutrophil elastase, MMP-8, MMP-9, MMP-12, IL-2, IL-4, IL-6, IL-8, IL-10, IL-18, IL-22, IL-23, IL-17, IFN-γ, TGFβ1, TNF-α) were analysed using commercially available kits. Besides, inhibitory effect of dexamethasone on proliferative response of PHA-stimulated peripheral blood lymphocytes had been assessed. Bcc infected patients did not differ from Bcc free ones in demographic and clinical parameters, but demonstrated an increased rate of glucose metabolism disturbances and survival disadvantage during prolong follow-up period. Biomarkers analyses revealed elevated TNF-α and reduced IL-17F levels in sputum samples of Bcc infected patients. These patients also demonstrated improvement of peripheral blood lymphocyte sensitivity to steroid treatment and reduction in plasma pro-inflammatory (IL-17F and IL-18) and anti-inflammatory (TGFβ1 and IL-10) cytokine concentrations. Reduction in IL-17F levels may have several important consequences including increase in steroid sensitivity and glycemic control disturbances. Further investigations are needed to clarify the role of IL-17 cytokines in CF complication development. Low plasma TGFβ1 and IL-10 levels in Bcc infected group may be a sign of subverted activity of regulatory T cells. Such immune alterations may be one of the factors contributing to the development of the cepacia syndrome.

Elucidating Genes and Transcription Factors of Human Peripheral Blood Lymphocytes Involved in the Cellular Response upon Exposure to Ionizing Radiation for Biodosimetry and Triage: An In Silico Approach

Abstract Background Gene expression–based biodosimetry is a promising method for estimating radiation dose following exposure. A panel of highly radio-responsive genes in human peripheral blood was used in the current investigation to create and evaluate a unique gene expression–based radiological biodosimetry method. Methodology In human cellular research, we reviewed the literature on genes and proteins correlating to radiation response in vivo and in vitro. We looked at two publicly accessible independent radiation response gene expression profiles (GSE1977 and GSE1725) and identified the differentially expressed genes (DEGs). Results The obtained data exhibited 42 genes with substantial differential expression, 25 of which were upregulated and 17 of which were downregulated in ionizing radiation exposure groups compared with control groups. The gene ontology enrichment analysis revealed that the hub genes are significantly involved in the regulation of the mitotic cell cycle phase transition, regulation of the mitotic cell cycle, and mitotic cell cycle checkpoint signaling. Out of the 42 DEGs, four top genes (CDK1, CCNB1, UBC, and UBB) were obtained through network centrality features. However, the multicomponent filtering procedure for radiation response genes resulted in cyclin-dependent kinase 1 (CDK1) as a critical gene in the dataset curated. Conclusion Our findings suggest the possibility of discovering novel gene connections involved in the cellular response of human peripheral blood lymphocytes upon exposure to ionizing radiation.

Phase II trial assessing safety, efficacy and immune correlates of heterologous prime-boost with pBI-11 (IM) and TA-HPV (IM) plus pembrolizumab for advanced, PD-L1 CPS≥1, hrHPV+ oropharyngeal cancer.

TPS6118 Background: HPV-related OPSCC occurs in younger patients, has a significantly better prognosis, and is most often caused by HPV subtype 16. There is a 90% overall survival for HPV+/p16+ OPSCC (40% for HPV-/p16- OPSCC), which can be cured with multimodality care. For patients with R/M disease, treatment with pembrolizumab (P) +/- chemotherapy is palliative, with a median OS of approximately 12 months for patients with PD-L1 combined positive score (cps) >1 treated with P alone. Heterologous prime boost with DNA priming followed by vaccinia-based boosting against HPV16 viral antigens will be studied using pBI-11 [(DNA vaccine pNGVL4a-SigE7 (detox)/HSP70, HPV16 E7(detox)/ HPV18 E7(detox), HPV16 E6(detox), and HPV18 E6(detox)] followed by TA-HPV (recombinant vaccinia-human papillomavirus (denoted TA-HPV) derived from the Wyeth strain of vaccinia which carries modified E6 and E7 genes from HPV types 16 and 18). This study is approved by the Vanderbilt University IRB and is open accrual (NCT NCT05799144). Methods: Patients with R/M, HPV positive OPSCC without prior therapy for R/M disease, without contraindications to immunotherapy and with a PD-L1 cps > 1 will be screened. There is a 6 patient safety run-in. Treatment with pBI-11 vaccine (2 IM injections on weeks 1 and 4) plus one IM administration of TA-HPV on week 7 will be given in combination with P IV on weeks 1, 4, and 7). Following restaging, all patients will continue (including those with PD) with 3 more cycles of P followed by restaging. The primary clinical outcome is RR to addition of vaccine in the 50% of predicted P non-responders (NR) who proceed to Part II (ie conversion to responders). All responders will continue to receive P until progression. Approximately 54 patients with be enrolled. Two research tumor biopsies and blood draws will be obtained pre- and on treatment (week7-9). Tumor tissue cores will be utilized for immunohistochemical and molecular tests (e.g., expression of immune cell and viral markers, TCR sequencing and total transcripts). Blood with be tested for HPV16/18 E6, E7 antibodies and vaccinia virus neutralizing assays; proliferative responses of peripheral blood lymphocytes to stimulation by HPV16/18 E6 and E7; HPV16/18 E6- and E7-Specific T cells; and HPV DNA in plasma. Data from the 1st four patients enrolled will be presented. Clinical trial information: NCT05799144 .

Chromosomal damage, gene expression and alternative transcription in human lymphocytes exposed to mixed ionizing radiation as encountered in space

Astronauts travelling in space will be exposed to mixed beams of particle radiation and photons. Exposure limits that correspond to defined cancer risk are calculated by multiplying absorbed doses by a radiation-type specific quality factor that reflects the biological effectiveness of the particle without considering possible interaction with photons. We have shown previously that alpha radiation and X-rays may interact resulting in synergistic DNA damage responses in human peripheral blood lymphocytes but the level of intra-individual variability was high. In order to assess the variability and validate the synergism, blood from two male donors was drawn at 9 time points during 3 seasons of the year and exposed to 0–2 Gy of X-rays, alpha particles or 1:1 mixture of both (half the dose each). DNA damage response was quantified by chromosomal aberrations and by mRNA levels of 3 radiation-responsive genes FDXR, CDKN1A and MDM2 measured 24 h post exposure. The quality of response in terms of differential expression of alternative transcripts was assessed by using two primer pairs per gene. A consistently higher than expected effect of mixed beams was found in both donors for chromosomal aberrations and gene expression with some seasonal variability for the latter. No synergy was detected for alternative transcription.

A study on the radiosensitivity and induction of adaptive response in peripheral blood lymphocytes of patients with secondary immunodeficiency syndrome

This study examined radiosensitivity at low and high dose exposure to X-rays in human lymphocytes and the ability of low and high dose radiation to induce radioadaptive response when the peripheral blood cells from patients with secondary immune deficiency syndrome and healthy donors of different ages were irradiated in vitro. The frequency of micronuclei in cytochalasin-blocked binuclear lymphocytes in culture served as an indication of cytogenetic damage. It was found that the spontaneous level of cytogenetic damage in blood lymphocytes of patients with secondary immune deficiency syndrome was 2.5 times greater than that of healthy young and older volunteers and there was also a substantial interindividual variability in outcome parameters as compared to the data of control groups. There were no differences in mean values for radiosensitivity at low and high dose exposure of X-rays between the groups. In all groups, no correlation was shown between the spontaneous level of micronuclei in lymphocytes and the radiosensitivity of individuals. The adaptive response was induced with the same frequency and to the same extent in lymphocytes in patients with secondary immune deficiency syndrome and in healthy donors of different ages.

Peripheral blood lymphocytes differ in DNA damage response after exposure to X-rays with different physical properties

Introduction: In radiology, low X-ray energies (<140 keV) are used to obtain an optimal image while in radiotherapy, higher X-ray energies (MeV) are used to eradicate tumor tissue. In radiation research, both these X-ray energies being used to extrapolate in vitro research to clinical practice. However, the energy deposition of X-rays depends on their energy spectrum, which might lead to changes in biological response. Therefore, this study compared the DNA damage response (DDR) in peripheral blood lymphocytes (PBLs) exposed to X-rays with varying beam quality, mean photon energy (MPE) and dose rate. Methods: The DDR was evaluated in peripheral blood lymphocytes (PBLs) by the ɣ-H2AX foci assay, the cytokinesis-block micronucleus assay and an SYTOX-based cell death assay, combined with specific cell death inhibitors. Cell cultures were irradiated with a 220 kV X-ray research cabinet (SARRP, X-Strahl) or a 6 MV X-ray linear accelerator (Elekta Synergy). Three main physical parameters were investigated: beam quality (V), MPE (eV) and dose rate (Gy/min). Additional copper (Cu) filtration caused variation in the MPE (78 keV, 94 keV, 118 keV) at SARRP; dose rates were varied by adjusting tube current for 220 kV X-rays (0.33–3 Gy/min) or water-phantom depth in the 6 MV set-up (3–6 Gy/min). Results: The induction of chromosomal damage and initial (30 min) DNA double-stranded breaks (DSBs) were significantly higher for 220 kV X-rays compared to 6 MV X-rays, while cell death induction was similar. Specific cell death inhibitors for apoptosis, necroptosis and ferroptosis were not capable of blocking cell death after irradiation using low or high-energy X-rays. Additional Cu filtration increased the MPE, which significantly decreased the amount of chromosomal damage and DSBs. Within the tested ranges no specific effects of dose rate variation were observed. Conclusion: The DDR in PBLs is influenced by the beam quality and MPE. This study reinforces the need for consideration and inclusion of all physical parameters in radiation-related studies.

A Study on the Radiosensitivity and Induction of Adaptive Response in Peripheral Blood Lymphocytes of Patients with Secondary Immunodeficiency Syndrome

A Study on the Radiosensitivity and Induction of Adaptive Response in Peripheral Blood Lymphocytes of Patients with Secondary Immunodeficiency Syndrome

Abstract 3231: Temporal changes in intratumoral and systemic lymphocytes in response to short and long course radiotherapy regimens in locally advanced rectal cancer

Abstract Background. Two pre-operative radiotherapy (RT) regimens are in common use for patients (pts) with locally advanced rectal cancer (LARC): Conventionally fractionated, long course chemoradiation (LCCRT, 25x1.8Gy with concomitant chemotherapy) or hypofractionated short-course RT (5X5Gy) followed by systemic chemotherapy (SCRT-C). RT is thought to induce immune responses to cellular damage, but the understanding of their evolution and relation to fractionation is limited. We are conducting a serial biospecimen collection in such pts with baseline, 2, 6 and 12 week (wk) sampling. We report serial measurement of tumor and peripheral blood lymphocyte responses for each regimen. Method. Multiplex immunofluorescence quantified tumor infiltrating lymphocytes (CD8, FOXP3). Routine diagnostic flow cytometry quantified circulating lymphocytes. A multiplex ELISA quantified cytokines in blood plasma. Bulk RNA-sequencing (QuantSeq) quantified gene expression within the tumor. Result. We report results for 20pts who received RT for stage III/IV LARC (13 LCCRT, 7 SCRT-C). Biopsy results are available for 10pts, circulating lymphocytes for 20pts and peripheral blood cytokines for 16pts. In LCCRT patients (n=8), relative to baseline, tumor infiltrating cytotoxic (CD8+) T cells were uniformly decreased during (2wks, P&amp;lt;0.05) and directly after treatment (6wks, P&amp;lt;0.05) before returning to baseline at 12wks. T regulatory cells (FOXP3+) similarly significantly decreased at 2wks and 6wks but remained below baseline at 12wks (P&amp;lt;0.05). Circulating lymphocytes also fell at wk2 and wk6 after commencing LCCRT and had begun recovering by wk12(n=13; P&amp;lt;0.05). The concentrations of circulating interleukins secreted by (IL2, IL8) or which activate T-lymphocytes (IL2, IL15) were reduced in the circulation at wk2 (n= 9; P&amp;lt;0.05) and wk6 (NS). In SCRT-C patients, we noted an increase in CD8 T cells at 2wks in 2/2 pts, also reflected in gene expression data, and an increase in FOXP3 T cells in 1/2 pts. Circulating lymphocytes were similarly decreased at wk2 in both the SCRT-C (n=7) and LCCRT (n=13) pts, but this reduction was less marked within the SCRT-C cohort at wk6 (P&amp;lt;0.01) and wk12 (P&amp;lt;0.05) relative to LCCRT patients. IL2, IL8 and IL15 did not change during or after SCRT-C (n=7; NS). Conclusion. LCCRT caused a drop in T cells during treatment, whilst SCRT-C appears to induce intra-tumoral T cell responses from wk2 and abrogates systemic reactions to a lesser extent. These results require evaluation in a larger cohort but have implications for understanding how RT induces microenvironmental changes and impacts pelvic bone marrow. We show in vivo that SCRT may be more immunostimulatory in LARC, with implications for trials combining RT with immunotherapy. Citation Format: Lily V. Hillson, Ross K. McMahon, Kathryn A. Pennel, Jean A. Quinn, Leia Jones, Raheleh Amirkhah, Aula Ammar, Phimmada Hatthakarnkul, Annabelle Ferguson, Simon W. Milling, Alec McDonald, Philip D. Dunne, Joanne Edwards, Sean M. O'Cathail, Campbell S. Roxburgh. Temporal changes in intratumoral and systemic lymphocytes in response to short and long course radiotherapy regimens in locally advanced rectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3231.

Changes in Radiosensitivity to Gamma-Rays of Lymphocytes from Hyperthyroid Patients Treated with I-131.

This study investigated the peripheral blood lymphocytes (PBL) response to a dose of γ-rays in patients treated with radioiodine (I-131) for hyperthyroidism vs. healthy controls, to gain information about the individual lymphocytes’ radio-sensitivity. Blood samples were taken from 18 patients and 10 healthy donors. Phosphorylated histone variant H2AX (γ-H2AX) and micronuclei (MN) induction were used to determine the change in PBL radio-sensitivity and the correlations between the two types of damage. The two assays showed large inter-individual variability in PBL background damage and in radio-sensitivity (patients vs. healthy donors). In particular, they showed an increased radio-sensitivity in 36% and 33% of patients, decrease in 36% and 44%, respectively. There was a scarce correlation between the two assays and no dependence on age or gender. A significant association was found between high radio-sensitivity conditions and induced hypothyroidism. PBL radio-sensitivity in the patient group was not significantly affected by treatment with I-131, whereas there were significant changes inter-individually. The association found between clinical response and PBL radio-sensitivity suggests that the latter could be used in view of the development of personalized treatments.

Differential activation of innate and adaptive lymphocytes during latent or active infection with Mycobacterium tuberculosis.

Most individuals infected with Mycobacterium tuberculosis (Mtb) have latent tuberculosis (TB), which can be diagnosed with tests (such as the QuantiFERON-TB Gold test [QFT]) that detect the production of IFN-γ by memory T cells in response to the Mtb-specific antigens 6 kDa early secretory antigenic target EsxA (Rv3875) (ESAT-6), 10 kDa culture filtrate antigen EsxB (Rv3874) (CFP-10), and Mtb antigen of 7.7 kDa (Rv2654c) (TB7.7). However, the immunological mechanisms that determine if an individual will develop latent or active TB remain incompletely understood. Here we compared the response of innate and adaptive peripheral blood lymphocytes from healthy individuals without Mtb infection (QFT negative) and from individuals with latent (QFT positive) or active TB infection, to determine the characteristics of these cells that correlate with each condition. In active TB patients, the levels of IFN-γ that were produced in response to Mtb-specific antigens had high positive correlations with IL-1β, TNF-α, MCP-1, IL-6, IL-12p70, and IL-23, while the proinflammatory cytokines had high positive correlations between themselves and with IL-12p70 and IL-23. These correlations were not observed in QFT-negative or QFT-positive healthy volunteers. Activation with Mtb-soluble extract (a mixture of Mtb antigens and pathogen-associated molecular patterns [PAMPs]) increased the percentage of IFN-γ-/IL-17-producing NK cells and of IL-17-producing innate lymphoid cell 3 (ILC3) in the peripheral blood of active TB patients, but not of QFT-negative or QFT-positive healthy volunteers. Thus, active TB patients have both adaptive and innate lymphocyte subsets that produce characteristic cytokine profiles in response to Mtb-specific antigens or PAMPs. These profiles are not observed in uninfected individuals or in individuals with latent TB, suggesting that they are a response to active TB infection.

Adaptive Response of Peripheral Blood Lymphocytes in Medical Radiation Workers using the Comet Assay: A Preliminary Studyomet Assay: A Preliminary Study

Background: Gamma irradiation can cause DNA damage in single and double-strand breaks (SSBs &amp; DSBs), especially in peripheral blood lymphocytes. Radiotherapy medical radiation workers can be exposed to gamma radiation related to their daily work. The comet assay is a sensitive method for analyzing DNA damage, especially SSBs. This study explores DNA damage in medical radiation workers’ peripheral blood lymphocytes as an adaptive response using the comet assay.Methods: Blood samples were obtained from four radiotherapy medical radiation workers as a case study (MRW) and two non-medical radiation workers as controls, and then irradiated with various doses of 0, 1, 1.5, and 2 Gy. Lymphocytes were isolated by histopaque and processed by comet assay on the slide under alkaline conditions. The imaging results were analyzed using the Casplab_1.2.3b2 software. The comet assay parameters observed were Tail Length (TL), % Tail DNA (T.DNA), Tail Moment (TM), and Olive Tail Moment (OTM). The one-way ANOVA method was used to analyze statistically between treatment groups. Results: Based on the study results, an increase in TL, T.DNA, TM, and OTM values in all samples was directly proportional to the increase in radiation dose. However, there was no significant difference (P &gt; 0.05) between the MRW group and the control group on each parameter of the comet assay.Conclusions: From this study, it can be concluded that the level of DNA damage of lymphocyte cells as part of the adaptive response in the MRW and control groups was relatively similar after exposure at doses of 0, 1, 1.5, and 2 Gy.

Susceptibility to chromosome instability and occurrence of the regular form of Down syndrome in young couples

Although the risk of pregnancy with Down syndrome (DS) increases with age, conceptions with trisomy 21 can occur in mothers aged 35 or less. The micronucleus test on peripheral blood lymphocytes is a well-recognized method for studying chromosomal instability. The aim of this study was to evaluate the application of the micronucleus assay and fluorescence in situ hybridization (FISH) for estimation of chromosome instability and occurrence of trisomy 21 in young parents having pregnancy or a child with the regular form of Down syndrome. The study included 54 parents (27 couples) who had previous pregnancy with trisomy 21 at age 35 or less. The control group consisted of 30 couples with two healthy children and no previous spontaneous abortions. Parents with trisomy 21 pregnancy had significantly higher frequencies of micronuclei in binucleated cells. There was no statistically significant difference between the study and control groups in the frequencies of micronuclei in mononuclear cells, nuclear buds, or nucleoplasmic bridges. FISH analysis showed higher percentages of micronuclei containing whole chromosomes as well as statistically significant higher numbers of micronuclei containing chromosome 21 in the peripheral blood of DS parents. There was no statistically significant difference between the two groups in the responses of peripheral blood lymphocytes to treatment with the mutagen mitomycin C. Our results suggest that young parents with a history of the regular form of Down syndrome have a higher susceptibility to chromosome nondisjunction in peripheral blood lymphocytes. The micronucleus assay showed high specificity, but moderate sensitivity, for risk assessment of trisomy 21 pregnancy.

Poly(Lactide-co-Glycolide) Nanoparticle-Mediated Vaccine Delivery of Encapsulated Surface Antigen Protein of Hepatitis B Virus Elicits Effective Immune Response.

Hepatitis B viral infection is one of the most important infectious diseases of the liver worldwide. Chronic infection with HBV often leads to cirrhosis and hepatocellular carcinoma. The currently licensed hepatitis B vaccine consists of recombinant hepatitis B surface antigen adsorbed into aluminum adjuvant and administered in three doses over the course of 6 months. However, this vaccine requires invasive administration and requires multiple booster doses. To avoid these limitations, nanoparticle (NP)-based vaccines lent itself as efficient adjuvants and delivery systems for the development of new generation vaccines. The biodegradable synthetic polymeric NPs poly(lactide-co-glycolide) (PLGA) was used in this study to formulate PLGA NPs encapsulated with hepatitis B surface protein to evaluate immune response in human peripheral blood lymphocytes in vitro. Formulation of HBP (HBV surface protein)-encapsulated PLGA (HB-nanovaccine [HB-NV]) was conducted by using double emulsion solvent evaporation technique (water-oil-water), which resulted in 94% encapsulation efficiency and 24% protein loading capacity. The resulted HB-NV had typical characteristics of spherical shape at an average size of 71.08 nm with higher densities and high stability dispersion of negatively charged NPs as assessed by atomic force microscopy, scanning electron microscopy, ultraviolet absorption spectrophotometry, zeta potential, and Fourier-transform infrared. The immune response to HB-NV was measured in vitro in lymphocytes, showed significant increase in levels of IL-2 and IFN-γ, as well as in CD4+ and CD8+ T cell counts, with a dose-dependent effect, examined by enzyme-linked immunosorbent assay and flow cytometry, respectively.

Адаптивный ответ как критерий оценки индивидуальной радиочувствительности человека. Обзор

Most studies of radioadaptive response (RAR) in vivo have revealed its effective induction both by chronic and single irradiation of a human organism with low doses. The classical way of the for-mation of RAR on the human peripheral blood lymphocytes (PBL) was noted as in occupationally irradiated personnel as in residents of areas with increased natural or man-made accidental high background radiation. In some studies, the liquidators of the Chernobyl accident and children liv-ing in the Chernobyl pollution zone showed the phenomenon of increasing the radiosensitivity of PBL. A comparative analysis of the influence of two types of radiation (gamma and betta) with close RBE showed comparable effectiveness to induce an adaptive response in human PBL in the mode of chronic exposure in the long term. Evidence of RAR in vivo was also obtained in the study of DNA end-points and chromosomal damage. In an experiment with the effect on neutrophils of peripheral blood of the elderly people (age 63-84 years) induced by acute gamma-rays in a wide range of doses (0.1; 0.25; 1; 4 and 10 Gy) the greatest radioresistance of their phagocytic and lysosomal activity is shown. Gamma-rays at low doses (0.1 Gy) stimulated the formation of extracellular traps by neutrophils in vitro using activated pyrogen (Pyrogernalum). The article presents some mechanisms of RAR in vivo. The study of radioadaptive response should be considered as an indispensable factor for assessing and controlling individual human radiosensitivity.

Study of modifying effects of astaxanthin on cytogenetic manifestations of bystander response in human peripheral blood lymphocytes in vitro.

To study the possible impact of astaxanthin on the cytogenetic manifestations of the simultaneous development of radiation-induced (RIBE) and tumor-induced bystander effect (TIBE) in human peripheral blood lymphocytes. Peripheral blood lymphocytes from healthy persons and patients with chronic lymphocytic leukemia were cultured separately or cocultured with or without previous irradiation in vitro by 137Cs at a dose of 0.5Gy. The cells were cultured with and without 20μg/ml astaxanthin. In the presence of astaxanthin, the decrease of chromosomal instability both in the variant with separate TIBE and with simultaneous development of TIBE and RIBE was observed as the reduction in the frequency of simple chromosome-type aberrations, namely, double fragments. The average level of chromatid-type aberrations did not change under the action of astaxanthin. Although the total chromosome instability in bystander cells diminished, this did not lead to the elimination of the RIBE and TIBE development in the presence of astaxanthin. In the setting of experiment, astaxanthin did not reduce the frequency of chromatid-type aberrations in bystander cells due to RIBE and TIBE but reduced the frequency of simple aberrations of chromosomal type, not associated with the development of bystander response phenomenon.

Evaluating Individual Radiosensitivity for the Prediction of Acute Toxicities of Chemoradiotherapy in Esophageal Cancer Patients.

In this work, individual radiosensitivity was evaluated using DNA damage response and chromosomal aberrations (CAs) in peripheral blood lymphocytes (PBLs) for the prediction of acute toxicities of chemoradiotherapy (CRT) in esophageal cancer patients. Eighteen patients with esophageal cancer were enrolled in this prospective study. Prescribed doses were 60 Gy in 11 patients and 50 Gy in seven patients. Patients received 2 Gy radiotherapy five days a week. PBLs were obtained during treatment just before and 15 min after 2 Gy radiation therapy on the days when the cumulative dose reached 2, 20, 40 Gy and 50 or 60 Gy. PBLs were also obtained four weeks and six months after radiotherapy in all and 13 patients, respectively. Dicentric and ring chromosomes in PBLs were counted to evaluate the number of CAs. Gamma-H2AX foci per cell were scored to assess DNA double-strand breaks. We analyzed the association between these factors and adverse events. The number of γ-H2AX foci before radiotherapy showed no significant increase during CRT, while their increment was significantly reduced with the accumulation of radiation dose. The mean number of CAs increased during CRT up to 1.04 per metaphase, and gradually decreased to approximately 60% six months after CRT. Five patients showed grade 3 toxicities during or after CRT (overreactors: OR), while 13 had grade 2 or less toxicities (non-overreactors: NOR). The number of CAs was significantly higher in the OR group than in the NOR group at a cumulative dose of 20 Gy (mean value: 0.63 vs. 0.34, P = 0.02), 40 Gy (mean value: 0.90 vs. 0.52, P = 0.04), and the final day of radiotherapy (mean value: 1.49 vs. 0.84, P = 0.005). These findings suggest that number of CAs could be an index for predicting acute toxicities of CRT for esophageal cancer.

An OMV-Based Nanovaccine Confers Safety and Protection against Pathogenic Escherichia coli via Both Humoral and Predominantly Th1 Immune Responses in Poultry.

Avian pathogenic Escherichia coli (APEC) infection in poultry causes enormous economic losses and public health risks. Bacterial outer membrane vesicles (OMVs) and nano-sized proteolipids enriched with various immunogenic molecules have gained extensive interest as novel nanovaccines against bacterial infections. In this study, after the preparation of APEC O2-derived OMVs (APEC_OMVs) using the ultracentrifugation method and characterization of them using electron microscopy and nanoparticle tracking analyses, we examined the safety and vaccination effect of APEC_OMVs in broiler chicks and investigated the underlying immunological mechanism of protection. The results showed that APEC_OMVs had membrane-enclosed structures with an average diameter of 89 nm. Vaccination with 50 μg of APEC_OMVs had no side effects and efficiently protected chicks against homologous infection. APEC_OMVs could be effectively taken up by chicken macrophages and activated innate immune responses in macrophages in vitro. APEC_OMV vaccination significantly improved activities of serum non-specific immune factors, enhanced the specific antibody response and promoted the proliferation of splenic and peripheral blood lymphocytes in response to mitogen. Furthermore, APEC_OMVs also elicited a predominantly IFN-γ-mediated Th1 response in splenic lymphocytes. Our data revealed the involvement of both non-specific immune responses and specific antibody and cytokine responses in the APEC_OMV-mediated protection, providing broader knowledge for the development of multivalent APEC_OMV-based nanovaccine with high safety and efficacy in the future.

Association Between Acute Toxicities Of Chemoradiotherapy And Chromosomal Aberrations In Peripheral Blood Lymphocytes In Esophageal Cancer Patients

The purpose of this study was to evaluate the individual radiosensitivity by analyzing the DNA damage response and chromosomal aberrations (CAs) in peripheral blood lymphocytes (PBLs) induced by chemoradiotherapy (CRT) and to predict non-hematologic acute toxicities of CRT in patients with esophageal cancer. Sixteen esophageal cancer patients referred to our institution for definitive CRT were enrolled in this prospective study. Prescribed doses were 60 Gy in 10 patients and 50 Gy in 6 patients. Patients received 2 Gy radiotherapy (RT) five days a week. Cisplatin or Nedaplatin (days 1 and 29) and 5-fluorouracil (days 1–4 and 29–32) were used as chemotherapy. PBLs were obtained during treatment just before and 15 minutes after delivering 2 Gy of RT on the day when the cumulative dose reached 2, 20, 40 and 50/60 Gy. PBLs were also obtained 4 weeks and 6 months after RT from all and thirteen patients, respectively. Dicentric and ring chromosomes in PBLs were counted to evaluate the numbers of CAs. γ-H2AX foci per cell were counted and the increment of γ-H2AX foci by 2 Gy RT was examined to assess DNA double-strand breaks. We assessed the association between these factors and adverse events of CRT evaluated using common terminology criteria for adverse events version 5.0. Paired t-test adjusted by Bonferroni correction and Mann-Whitney U test were used to compare the indices from the same group at different timings and the indices between two groups, respectively. For all analyses, a P value of < 0.05 was considered significant. The mean numbers of CAs per 1,000 cells increased during CRT and decreased after RT: before RT, 13 (range: 0–24); 2 Gy, 50 (31–82); 20 Gy, 442 (218–1,099); 40 Gy: 710 (338–1,333); the last day of RT (50 or 60 Gy), 1,089 (567–2,295); 4 weeks after RT: 1,019 (455–2,063); and 6 months after RT: 646 (269–1,217). The mean numbers of γH2AX foci per cell before RT showed no increase during CRT. The mean increment of γH2AX foci per cell by 2 Gy RT was significantly reduced with accumulation of RT dose: 2Gy, 1.95 (0.57–3.33); 20 Gy, 1.70(0.59–3.17); 40 Gy: 1.01 (0.06–1.88); and the last day of RT (50 or 60 Gy), 0.69 (0.08–2.19), even though the same dose was administered each day. Five patients showed grade 3 toxicities during or after CRT (overreactors: OR), while eleven had grade 2 or less toxicities (non-overreactors: NOR). The numbers of CAs were significantly higher in the OR group than in the NOR group at a cumulative dose of 20 Gy (mean value: 625 vs 355, P = 0.02), 40 Gy (mean value: 903 vs 571, P = 0.04), and the last day of RT (mean value: 1485 vs 869, P = 0.007). The number and increment of γH2AX foci did not show a significant association with acute toxicities. The number of CAs after CRT increased as the cumulative doses increased, while the increment of γ-H2AX foci decreased with an increase in cumulative dose. The number of CAs could be an index for predicting non-hematologic acute toxicities of CRT for esophageal cancer.