Transgenic expression of artificial microRNA targeting soybean mosaic virus P1 gene confers virus resistance in plant.

RNA silencing is an innate immune mechanism of plants against invasion by viral pathogens. Artificial microRNA (amiRNA) can be engineered to specifically induce RNA silencing against viruses in transgenic plants and has great potential for disease control. Here, we describe the development and application of amiRNA-based technology to induce resistance to soybean mosaic virus (SMV), a plant virus with a positive-sense single-stranded RNA genome. We have shown that the amiRNA targeting the SMV P1 coding region has the highest antiviral activity than those targeting other SMV genes in a transient amiRNA expression assay. We transformed the gene encoding the P1-targeting amiRNA and obtained stable transgenic Nicotiana benthamiana lines (amiR-P1-3-1-2-1 and amiR-P1-4-1-2-1). Our results have demonstrated the efficient suppression of SMV infection in the P1-targeting amiRNA transgenic plants in an expression level-dependent manner. In particular, the amiR-P1-3-1-2-1 transgenic plant showed high expression of amiR-P1 and low SMV accumulation after being challenged with SMV. Thus, a transgenic approach utilizing the amiRNA technology appears to be effective in generating resistance to SMV.

Investigation and characterization of rice dwarfing epidemic caused by southern rice black-streaked dwarf virus in Jiangsu in 2023.

During the field surveys in Jiangsu Province, China, contiguous patches of rice plants with varying degrees of dwarfing, wax-white or dark brown enations at the base of stems, and abnormal heading symptoms were observed in the fields located in Jiangning District in Nanjing City, Jurong County in Zhenjiang City, and Zhangjiagang County in Suzhou City. Through molecular analyses, the presence of southern rice black-streaked dwarf virus was confirmed in symptomatic rice plants. The infections of other rice viruses that cause dwarfing were also ruled out. Additionally, Koch's postulates were fulfilled, further validating SRBSDV as the causal agent for the observed dwarfing disease epidemic. Furthermore, the phylogenetic analyses revealed that the SRBSDV prevalent in Jiangsu in 2023 may originate from multiple regions in Vietnam. Our study has documented the emergence of an SRBSDV epidemic in Jiangsu in 2023, marking the first incidence of southern rice black-streaked dwarf disease in this region.

Interlayer Biatomic Pair Bridging the van der Waals Gap for 100% Activation of 2D Layered Material.

2D layered materials are regarded as prospective catalyst candidates due to their advantageous atomic exposure ratio. Nevertheless, the predominant population of atoms residing on the basal plane with saturated coordination, exhibit inert behavior, while a mere fraction of atoms located at the periphery display reactivity. Here, a novel approach is reported to attain complete atom activation in 2D layered materials through the construction of an interlayer biatomic pair bridge. The atoms in question have been strategically optimized to achieve a highly favorable state for the adsorption of intermediates. This optimization results from the introduction of new gap states around the Fermi level. Moreover, the presence of the interlayer bridge facilitates the electron transfer across the van der Waals gap, thereby enhancing the reaction kinetics. The hydrogen evolution reaction exhibits an impressive ultrahigh current density of 2000 mA cm-2 at 397 mV, surpassing the pristine MoS2 by approximately two orders of magnitude (26 mA cm-2 at 397 mV). This study provides new insights for enhancing the efficacy of 2D layered catalysts.

Prognostic Value of Non-alcoholic Fatty Liver Disease and RCA Pericoronary Adipose Tissue CT Attenuation in Patients with Acute Chest Pain.

RATIONALE AND OBJECTIVES: Pericoronary adipose tissue (PCAT) CT attenuation of right coronary artery (RCA) and non-alcoholic fatty liver disease (NAFLD) have prognostic value for major adverse cardiovascular events (MACE) in patients with coronary artery disease. However, the superior prognostic value between RCA PCAT CT attenuation and NAFLD remains unclear in patients with acute chest pain. This study is to evaluate the prognostic value of NAFLD for MACE, and further assess the incremental prognostic value of NAFLD over PCAT CT attenuation. MATERIALS AND METHODS: Between January 2011 and December 2021, all consecutive emergency patients with acute chest pain referred for coronary CT angiography (CCTA) were retrospectively enrolled. MACE included unstable angina requiring hospitalization, coronary revascularization, non-fatal myocardial infarction, and all-cause death. Patients' baseline and CCTA characteristics, RCA PCAT CT attenuation, and the presence of NAFLD were used to evaluate risk factors of MACE using multivariable Cox regression analysis. The prognostic value of NAFLD compared to RCA PCAT CT attenuation was analyzed. RESULTS: A total of 514 patients were enrolled (mean age, 58.36 ± 13.05 years; 310 men). During a median follow-up of 31 months, 60 patients (11.67%) experienced MACE. NAFLD (HR = 2.599, 95% CI: 1.207, 5.598, P = 0.015) and RCA PCAT CT attenuation (HR = 1.026, 95% CI: 1.001, 1.051, P = 0.038) were independent predictors of MACE. The global Chi-square analysis showed that NAFLD improved the risk of MACE more than that using clinical risk factors and CCTA metrics (59.51 vs 54.44, P = 0.024) or combined with RCA PCAT CT attenuation (63.75 vs 59.51, P = 0.040). CONCLUSION: NAFLD and RCA PCAT CT attenuation were predictors of MACE. NAFLD had an incremental prognostic value beyond RCA PCAT CT attenuation for MACE in patients with acute chest pain. Adding CT-FFR into the risk prediction of patients with acute chest pain is worth considering.

Association of Objective Sleep Characteristics and Incident Angina Pectoris: A Longitudinal Analysis from the Sleep Heart Health Study.

Purpose: While prior research has highlighted a significant association between sleep characteristics and angina pectoris (AP) incidence, the link between sleep efficiency (SE) and angina remains unexplored. This study seeks to elucidate the relationship between AP and objectively quantified SE. Patients and Methods: We examined a cohort of 2990 participants (1320 males and 1670 females; mean age 63.69 ± 13.2 years) from the Sleep Heart Health Study. The main exposure variable was SE, as determined by baseline home polysomnography, while the primary outcome was the first incidence of angina pectoris (AP) during the period between the baseline polysomnography and the end of follow-up. A multivariate Cox regression model was utilized, controlling for factors such as age, gender, BMI, smoking and alcohol consumption habits, diabetes, hypertension, sleep duration, triglycerides, cholesterol, high-density lipoprotein, apnea-hypopnea index, nocturnal oxygen saturation, to analyze the relationship between SE and AP. Results: During an average follow-up of 11 years, 284 patients developed AP. The unadjusted Kaplan-Meier analysis identified the 2nd quartile of SE as having the lowest AP risk. The multivariate Cox proportional hazards model demonstrated a higher risk of AP in quartile 1 (HR, 1.679; 95% CI, 1.109-2.542; P <0.014) and quartile 3 (HR, 1.503; 95% CI, 1.037-2.179; P <0.031), compared to quartile 2 of SE. Upon stratified analysis, this relationship was particularly pronounced in hypertensive individuals. Conclusion: Our results highlight the critical role of optimal sleep efficiency in mitigating the risk of angina pectoris, especially among hypertensive individuals.

Association with cationized gelatin nanospheres enhances cell internalization of mitochondria efficiency.

The objective of this study is to confirm the methodological feasibility of cationized gelatin nanospheres (cGNS) to enhance the internalization efficiency of mitochondria (Mt) isolated to cells for their increasing functions. The cGNS were simply associated on the surface of Mt by the electrostatic interaction. Different sizes of cGNS were used to allow Mt to associate on the Mt surface (Mt-cGNS). As a control, cationized gelatin (cG) was used to modify the Mt surface (Mt-cG). The Mt-cG and Mt-cGNS prepared were cultured with H9c2 cells to examine their internalization. The internalization efficiency significantly increased by utilizing cGNS. However, there was no significant difference in the internalization efficiency among cGNS with different sizes. After incubation of Mt, Mt-cG, and Mt-cGNS, the superoxide amount and ATP generation were evaluated. Significantly lower superoxide amount and higher ATP amount were observed for the Mt-cGNS group compared with those of non-modified Mt group. It is conceivable that cGNS enhance the cellular internalization of Mt, leading to an improve mitochondrial functions in the recipient cells. In conclusion, cGNS are promising to improve the efficacy in mitochondria internalization.

A Reverse Transfection System with Cationized Gelatin Nanospheres Incorporating Molecular Beacon as a Tool to Visualize Cell Function.

The objective of this research is to design a reverse transfection system with cationized gelatin nanospheres (cGNS) incorporating a molecular beacon (MB) to visualize a cell function. The cGNS were prepared by the conventional coacervation method. The MB as an imaging probe was incorporated into the cGNS to prepare imaging complexes (cGNSMB). The conventional transfection of 2D culture was performed by incubating MC3T3 cells in the medium containing cGNSMB. The reverse transfection was done by incubating cells on the substrate which had been precoated with both gelatin and cGNSMB. Significantly higher internalization efficiency and fluorescence intensity of cGNSMB were observed in the reverse transfection system than in the conventional one. To apply this system for visualization of 3D cell aggregate, gelatin microspheres (GMS) were prepared, while cGNSMB were bound on the GMS to prepare the GMS-cGNSMB of a cell scaffold. Then the cells were incubated with GMS-cGNSMB to form 3D cell aggregates. On the other hand, as a control, the conventional transfection of 3D culture was performed by incubating the cell aggregates formed with the medium containing cGNSMB. Homogeneous fluorescence of MB from the inside to the outside of aggregates was observed for the reverse transfection group. However, for the conventional transfection, the fluorescence was observed only around the surface of cell aggregates. It is concluded that the reverse transfection system with cGNS incorporating MB is promising to visualize the cell function of a higher transfection efficiency for the 2D culture and in a homogeneous manner for the 3D culture.

Proton and Carbon Ion Radiation Therapy Decreased Severe Lymphopenia by Reducing Thoracic Vertebra and Aortic Doses in Non-Small Cell Lung Cancer Versus Intensity Modulated Radiation Therapy.

PURPOSE: Lymphopenia is a common adverse effect of radiation therapy (RT). Little is known about the difference in lymphopenia between intensity modulated (photon) radiation therapy (IMRT) and proton and carbon ion radiation therapy (PCIRT). This study aimed to investigate lymphopenia differences between IMRT and PCIRT in non-small cell lung cancer (NSCLC). METHODS AND MATERIALS: Clinical and dosimetric parameters were collected from 343 patients who received definitive IMRT or PCIRT for NSCLC. Severe lymphopenia (SRL) was defined as an absolute lymphocyte count (ALC) ≤0.5 × 103 cells/µL. Overall survival (OS) was analyzed using the Kaplan-Meier method. Propensity score matching was performed between the IMRT and PCIRT groups. Least absolute shrinkage and selection operator analysis was used to select appropriate dosimetric parameters. Univariate and multivariate logistic regression analyses were conducted to identify the predictors of SRL. RESULTS: Compared with the IMRT group, the PCIRT group was less likely to develop SRL (P < .001). Compared with the non-SRL group, the SRL group showed significant association with poorer OS, with a median survival time of 29.2 versus 15.0 months (P = .046). IMRT was an independent risk factor of SRL (P = .004). A lower ALC before RT (P = .030) and larger planning target volume (PTV) (P = .002) were also significant independent risk factors for SRL. Moreover, the majority of dosimetric parameters of organs at risk in PCIRT were lower than those in IMRT (P < .001). Thoracic vertebra V5 (P = .002) and aorta V5 (P = .026) were identified as independent risk predictors of SRL after adding dosimetric parameters to the regression model. CONCLUSIONS: Compared with IMRT, PCIRT could reduce SRL incidence, possibly by limiting thoracic vertebra and aortic doses, and SRL was associated with poor outcomes in patients with NSCLC.

Dynamic Compensation Method for Humidity Sensors Based on Temperature and Humidity Decoupling.

Currently, integrated humidity sensors with fast-response time are widely needed. The most commonly used polyimide capacitive humidity sensor has a long response time, which is difficult to meet the need for a fast response. Most studies focusing on technology and materials have a high cost and are difficult to ensure compatability with the CMOS process. The dynamic compensation method can shorten the response time by only adding digital circuits or software processing. However, conventional compensation technology is not suitable for humidity sensors due to temperature coupling. This paper proposes a new dynamic compensation method for humidity sensors based on the decoupling of temperature factors by analyzing the coupling relationship between sensor dynamic characteristics and temperature. Simulations and experiments were used to verify the proposed method. The experimental results show that the proposed method reduces the humidity response time of the sensor by 85.6%. The proposed method can effectively shorten the response time of humidity sensors.

Low frequency vibrating magnetic field-triggered magnetic microspheres with a nanoflagellum-like surface for cancer therapy.

BACKGROUND: The magneto-mechanical force killing cancer cells is an interesting and important strategy for cancer therapy. RESULTS: Novel magnetic microspheres composed of a Fe3O4 nanocore, a bovine serum albumin (BSA) matrix, and a rod-like SiO2 nanoshell, which had flagellum-like surface for force-mediated cancer therapy were developed. One such magnetic microsphere (Fe3O4/BSA/rSiO2) at a cancer cell (not leave the cell surface) under a low frequency vibrating magnetic field (VMF) could generate 6.17 pN force. Interestingly, this force could induce cancer cell to generate reactive oxygen species (ROS). The force and force-induced ROS could kill cancer cells. The cell killing efficiency of Fe3O4/BSA/rSiO2 exposed to a VMF was enhanced with increasing silica nanorod length, and the microspheres with straight nanorods exhibited stronger cell killing ability than those with curled nanorods. Fe3O4/BSA/rSiO2 triggered by a VMF could efficiently inhibit mouse tumor growth, while these microspheres without a VMF had no significant effect on the cell cycle distribution, cell viability, tumor growth, and mouse health. CONCLUSIONS: These microspheres with unique morphological characteristics under VMF have great potential that can provide a new platform for treating solid tumors at superficial positions whether with hypoxia regions or multidrug resistance.

Potential Method of Autophagy Imaging with Cationized Gelatin Nanospheres Incorporating Molecular Beacon.

The objective of this research is to develop an imaging method with cationized gelatin nanospheres incorporating molecular beacon (cGNSMB) to visualize an autophagy activity in living cells. Cationized gelatin nanospheres (cGNS) were prepared by the conventional coacervation method, and then molecular beacon (MB) was incorporated into them. The cGNSMB prepared were internalized into cells at a high efficiency. In this study, a starvation medium of serum and amino acids-free was used to induce autophagy. The autophagy activity was confirmed by an immunofluorescence staining for microtubule-associated proteins light chain 3B (LC3B) of an autophagy specific protein. With the autophagy induction time, the number of LC3 fluorescent dots increased, which indicated an increased autophagy activity. As the autophagy-related genes, sequestosome 1 (SQSTM1) and cathepsin F (CTSF), which up-regulate after autophagy induction, were chosen as the targets of cGNSMB. The fluorescence intensity of cGNSMB targeting to SQSTM1 and CTSF increased with the starvation treatment time, which well corresponded with the gene expression results. When applied to cells in different autophagy conditions, the cGNSMB visualized the autophagy activity corresponding with the autophagy condition of cells. From the results obtained, it was concluded that the cGNSMB provide a promising method to visualize the autophagy of cells. The advantage of cGNSMB visualization is to obtain the temporal and spatial information without destroying sample cells.

Two-Stage Intelligent Multi-Type Artifact Removal for Single-Channel EEG Settings: A GRU Autoencoder Based Approach.

OBJECTIVE: The wearable and portable Electroencephalogram (EEG) sensing systems are deeply interfered by unavoidable physiological artifacts due to the limited recording resources. In this work, an intelligent artifact removal system that handles single-channel EEG signals in the presence of mixed multi-type artifacts is investigated. METHODS: The basic idea is to represent the mixed artifacts in contaminated varying EEG signals with the unchanged latent pattern features, and then employ the adaptive artifact removal scheme to separate the contamination and clean EEG signals in the encoded feature domain. To minimize the risks of corrupting clean signals and keeping artifacts by mistake, the artifact removal is formulated as an identification-removal two-stage minimization problem, and an attention based adaptive feature concentration mechanism is designed to improve the removal utility and reduce the calculation consumption. RESULTS: In the real implementation on open real-world dataset, this study achieves the artifact identification accuracy of 98.52% and average correlation coefficient of 0.73 for the removal of strong mixed multi-type artifacts. CONCLUSION: This study can deal with single-channel EEG signals contaminated by mixed multi-type artifacts with high accuracy and low overhead, and is more effective and stable than traditional schemes with fixed criteria. SIGNIFICANCE: This study can significantly improve the signal quality acquired by simplified EEG sensing systems, and may extend the application of wearable and portable EEG sensing systems to medical diagnosis, cognitive science research and other applications requiring clinical setups.

A bioprosthetic heart valve cross-linked by a non-glutaraldehyde reagent with improved biocompatibility, endothelialization, anti-coagulation and anti-calcification properties.

Valvular heart disease is an important disease that endangers human health and heart valve replacement has become one of the main treatments for patients with severe valvular heart disease. However, the traditional surgical valve replacement (SVR) suffers several drawbacks such as high risk, great trauma and long recovery time, and more than 30% of patients are intolerant to SVR, especially elderly patients. In recent years, with the development of minimally invasive technology, transcatheter heart valve replacement (THVR) as a method of implantation without thoracotomy has become an optimal treatment for severe valvular heart disease due to its advantages of minimal trauma, low risk and fast recovery. Meanwhile, the usage of bioprosthetic heart valves (BHVs) has been enlarged greatly with the rapid development of THVR and the aging population. Most BHVs in clinics are crosslinked by glutaraldehyde (Glut), which shows great mechanical properties and chemical stability. However, some problems such as poor biocompatibility, calcification, coagulation and endothelialization difficulty also need to be solved urgently for Glut-treated BHVs. In this work, a non-Glut treated BHV from 7a-ethyltetrahydro-oxazolo[3,4-c]oxazole (OX-Et) crosslinked porcine pericardium (PP) has been developed. Compared with glutaraldehyde-crosslinked porcine pericardium (Glut-PP), good physical and chemical properties similar to Glut-PP are shown for OX-Et treated porcine pericardium (OX-Et-PP). It is noteworthy that better biocompatibility, endothelialization performance, and anti-coagulant effect as well as the improved anti-calcification property can also be observed for OX-Et-PP in the in vitro and in vivo study, potentially making OX-Et-PP a good candidate in the application of BHVs.

Clusterin inhibits Aß42 aggregation through a "strawberry model" as detected by FRET-FCS.

Extracellular plaque deposits of ß-amyloid peptide (Aß) are one of the main pathological features of Alzheimer's disease (AD). The aggregation of Aß42 species, especially Aß42 oligomers, is still an active research field in AD pathogenesis. Secretory clusterin protein (sCLU), an extracellular chaperone, plays an important role in AD pathogenesis. Although sCLU interacts directly with Aß42 in vitro and in vivo, the mechanism is not clear. In this paper, His-tagged sCLU (sCLU-His) was cloned, expressed and purified, and we applied florescence resonance energy transfer-fluorescence correlation spectroscopy (FRET-FCS) to investigate the direct interaction of sCLU-His and Aß42 at the single-molecule fluorescence level in vitro. Here, we chose four different fluorescently labeled Aß42 oligomers to form two different groups of aggregation models, easy or difficult to aggregate. The results showed that sCLU-His could form complexes with both aggregation models, and sCLU-His inhibited the aggregation of Aß42/RB  ~ Aß42/Atto647 (easy to aggregate model). The complexes were produced as the Aß42/Label adhered to the sCLU-His, which is similar to a "strawberry model," as strawberry seeds are dotted on the outer surface of strawberries. This work provided additional insight into the interaction mechanism of sCLU and Aß42 .

Fluorescent hollow mesoporous carbon spheres for drug loading and tumor treatment through 980-nm laser and microwave co-irradiation.

Hollow mesoporous particles for drug delivery and cancer therapy have attracted significant attention over recent decades. Here, we develop a simple and highly efficient strategy for preparing fluorescent hollow mesoporous carbon spheres (HMCSs). Compared with typical carbon materials such as fullerene C60, carbon nanotubes, reduced graphene oxide, and carbon nanohorns; HMCSs showed fewer effects on cell cycle distribution and lower toxicity to cells. Ten different drugs were incorporated into the HMCSs, and the maximum loading efficiency reached 42.79 ± 2.7%. Importantly, microwaves were found to improve the photothermal effect generated by HMCSs when combined with 980-nm laser irradiation. The cell killing and tumor growth inhibition efficiencies of HMCSs and drug-loaded HMCSs under co-irradiation with laser and microwaves were significantly improved compared with those under laser irradiation alone. After local administration HMCSs were only distributed in tissue at the injection site. HMCSs showed almost no toxicity in mice after local injection and could be completely removed from the injection site.

A cluster of patients with rhabdomyolysis after eating crayfish.

Crayfish or Procambarus clarkii is a freshwater crustacean with worldwide distribution. Tons of crayfish are consumed each year. In this report, four adult patients with rhabdomyolysis after consuming crayfish were described. All of them presented to the emergency department with myalgia. The diagnosis of rhabdomyolysis was supported by an elevated creatine kinase level. All recovered with supportive treatment. The clinical picture of these 4 patients was compatible with Haff disease. Haff disease is a syndrome in which rhabdomyolysis develops subsequent to consumption of certain cooked seafood. Crayfish is a common culprit. Diagnosis depends on obtaining a diet history and creatine kinase level. Most patients recover uneventfully with supportive treatment for rhabdomyolysis.

[Influence of Ureaplasma Urealyticum Infection on Testicular Tissue Structure and Secretion Function in Rats].

OBJECTIVE: To study the influences of ureaplasma urealitycum (UU) infection on testicular tissue structure and secretion function in rats. METHODS: Forty clean grade male SD rats were randomly divided into the experiment group A (at 7 d after surgery), experiment group B (at 14 d after surgery), control group C (at 7 d after surgery) and control group D (at 14 d after surgery). There were 10 rats in each group. The experimental groups were injected with 0.6 mL UU4 through bladder. In the same way, the control groups were injected with the same volume of UU liquid medium. At day 7 and 14 after injection, the structures of testis of all rats were observed by light microscopy and spermatogenic cells by transmission electron microscopy. The content of testosterone in plasma and testicular fluid were detected by chemiluminescence method. RESULTS: The changes of inflammatory pathology (including the layer and amount of spermatogenic cell decreasing, inflammatory cell infiltrating and mature sperms decreasing) in the testis of group A and group B were found by light microscopy, and the inflammatory changes in group B were lighter than those in group A. The structures of testicular tissue in group C and group D were normal. The apoptosis performances of germ cell (including the cell membrane corrugated, nuclear chromatin concentration and nuclear rupture) in the testis of group A and group B were found by transmission electron microscopy, and the changes in group B were lighter than those in group A. The structures of germ cell in group C and group D were normal. The levels of plasma testosterone in group A and group B were significantly lower than that in group C and group D (P<0.01), the difference between group A and group B was not statistically significant. The testosterone level in testis interstitial fluid in group A was significantly lower than that in other groups (P<0.01), the differences between other groups were not statistical significant. CONCLUSIONS: The testicular tissue of UU infected rats can have various pathological damage and functional changes, further confirming that UU infection can cause male infertility. The pathological damage and functional changes of the testicular tissue of rats after UU infection can be gradually restored with the extension of the duration of the disease.

Correlation between Heart-type Fatty Acid-binding Protein Gene Polymorphism and mRNA Expression with Intramuscular Fat in Baicheng-oil Chicken.

This study aims to determine the polymorphism and mRNA expression pattern of the heart-type fatty acid-binding protein (H-FABP) gene and their association with intramuscular fat (IMF) content in the breast and leg muscles of Baicheng oil chicken (BOC). A total of 720 chickens, including 240 black Baicheng oil chicken (BBOC), 240 silky Baicheng oil chicken (SBOC), and 240 white Baicheng oil chicken (WBOC) were raised. Three genotypes of H-FABP gene second extron following AA, AB, and BB were detected by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) strategy. The G939A site created AA genotype and G956A site created BB genotype. The content of IMF in AA genotype in breast muscle of BBOC was significantly higher than that of AB (p = 0.0176) and the genotype in leg muscle of WBOC was significantly higher than that of AB (p = 0.0145). The G939A site could be taken as genetic marker for higher IMF content selecting for breast muscle of BBOC and leg muscle of WBOC. The relative mRNA expression of H-FABP was measured by real-time PCR at 30, 60, 90, and 120 d. The IMF content significantly increased with age in both muscles. The mRNA expression level of H-FABP significantly decreased with age in both muscles of the three types of chickens. Moreover, a significant negative correlation between H-FABP abundance and IMF content in the leg muscles of WBOC (p = 0.035) was observed. The mRNA expression of H-FABP negatively correlated with the IMF content in both breast and leg muscles of BOC sat slaughter time.

Staphylococcal enterotoxin B administration during pregnancy imprints the increased CD4:CD8 T-cell ratio in the peripheral blood from neonatal to adult offspring rats.

Our previous study demonstrated that Staphylococcal enterotoxin B (SEB) administration during pregnancy could alter the percentage of T cells subpopulation in the thymus of the neonatal rats; however, little is known about the effect of maternal SEB administration during pregnancy on T cells subpopulation in the peripheral blood of the offspring rats. In the present study, pregnant rats at gestational day 16 were intravenously injected with 15 µg SEB. The present study found that prenatal exposure to SEB significantly decreased the percentages of CD8 T cells in the peripheral blood of both neonatal rats on the fifth day after delivery and the adult offspring rats. Furthermore, it significantly increased the percentage of CD4 T cells as well as the ratios of CD4 to CD8 T cells in both neonatal and adult offspring rats. Prenatal exposure to SEB significantly decreased the expression levels of IL-4 and IFN-γ in the plasma of neonatal and adult offspring rats. Furthermore, SEB restimulation significantly increased the percentage of CD8 T cells and significantly decreased the percentage of CD4 T cells. These data suggest the prenatal exposure to SEB can imprint the increased CD4:CD8 T cell ratio in the peripheral blood from the neonate to adulthood through the decreased CD8 T cells and the increased CD4 T cells, and altered the response characteristics of CD4 and CD8 T cells to secondary SEB administration in the peripheral blood of the adult offspring rats.