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BACKGROUND: Marginal zone lymphomas (MZLs) comprise a diverse group of indolent lymphoproliferative disorders; however, some patients develop histologic transformation (HT) with rapid progression to aggressive lymphoma. METHODS: Forty-three MZLs with HT (HT-MZLs), 535 MZLs, and 174 de novo diffuse large B-cell lymphomas (DLBCLs) without rearrangements of MYC, BCL2, and BCL6 were collected. Among these, 22 HT-MZLs, 39 MZLs, and 174 DLBCLs were subjected to 148-gene targeted exome sequencing. The clinicopathologic features of patients who had HT-MZL and their genetic alterations were compared with those of patients who had MZLs and DLBCLs. RESULTS: All 43 HT-MZLs corresponded to DLBCLs. No HT-MZLs harbored BCL2 and MYC and/or BCL6 rearrangements. Bone marrow involvement and higher levels of lactate dehydrogenase were significantly more common in HT-MZLs than in MZLs. Furthermore, upregulated BCL6, MUM1, C-MYC, and Ki-67 expression was observed more frequently in HT-MZLs than in MZLs. TBL1XR1 was the most frequently altered gene (63.6%) in HT-MZLs, followed by CCND3 (31.8%), CARD11, ID3, and TP53 (22.7%). A trend toward worse progression-free survival in patients with TBL1XR1 mutations was observed. Compared with MZLs and non-germinal center B-cell (GCB) type DLBCLs, significantly higher frequencies of TBL1XR1 and ID3 mutations were identified in HT-MZLs. PIM1 mutations frequently occurred in DLBCLs and were significantly associated with TBL1XR1 mutations but were mutated less in HT-MZLs that had TBL1XR1 mutations. CONCLUSIONS: The current findings reveal the clinicopathologic and genetic features of HT-MZLs, suggesting that these tumors might constitute a group distinct from MZL and de novo non-GCB type DLBCL. TBL1XR1 mutations may be considered a predictor of HT in MZL.
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Linfoma de Células B de la Zona Marginal , Linfoma de Células B Grandes Difuso , Humanos , Linfoma de Células B de la Zona Marginal/genética , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/patología , Supervivencia sin Progresión , Proteínas Proto-Oncogénicas c-bcl-2/genéticaRESUMEN
BACKGROUND: The aim of this study was to assess homologous recombination deficiency (HRD) status and its correlation with carboplatin treatment response in early triple-negative breast cancer (TNBC) patients. METHODS: Tumor tissues from 225 consecutive TNBC patients were evaluated with an HRD panel and homologous recombination-related (HRR) gene expression data. HRD positivity was defined as a high HRD score and/or BRCA1/2 pathogenic or likely pathogenic mutation. Clinicopathological factors, neoadjuvant treatment response, and prognosis were analyzed with respect to HRD status in these TNBC patients. RESULTS: HRD positivity was found in 53.3% of patients and was significantly related to high Ki67 levels (P = 0.001). In patients who received neoadjuvant chemotherapy, HRD positivity (P = 0.005) or a high HRD score (P = 0.003) was significantly associated with a greater pathological complete response (pCR) rate, especially in those treated with carboplatin-containing neoadjuvant regimens (HRD positivity vs. negativity: 50.00% vs. 17.65%, P = 0.040). HRD positivity was associated with favorable distant metastasis-free survival (hazard ratio HR 0.49, 95% confidence interval CI 0.26-0.90, P = 0.022) and overall survival (HR 0.45, 95% CI 0.20-0.99, P = 0.049), irrespective of carboplatin treatment. CONCLUSION: TNBC patients with high HRDs had high Ki67 levels and BRCA mutations. HRD-positive TNBC patients treated with carboplatin had a higher pCR rate. Patients with HRD positivity had a better prognosis, irrespective of carboplatin treatment, warranting further evaluation.
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OBJECTIVE: To investigate the correlation between programmed death ligand-1 (PD-L1) expression and tumor-infiltrating lymphocytes (TILs) and evaluate the prognostic value of PD-L1 and TILs in Chinese triple-negative breast cancer (TNBC) patients with different molecular subtype METHODS: This retrospective study was conducted at 2020. Specifically, the pre-chemotherapy clinical data and non-stained tissue blocks of 465 TNBC patients visited the Fudan University Shanghai Cancer Center (FUSCC) between 2008 and 2014 were collected, with their blocks sliced and stained using PD-L1(SP142), and the outcome of subsequent chemotherapy obtained in 2020. The relapse-free survival (RFS) of the study population was calculated. The baseline PD-L1 expression status correlations with TILs and molecular subtypes were assessed using Spearman's rank correlation analysis and the Kruskal-Wallis test. Kaplan-Meier survival analyses were undertaken to evaluate the prognosis value of TILs and PD-L1 expression. RESULTS: PD-L1 expression status on IC was moderately and positively correlated with stromal tumor-infiltrating lymphocytes (sTILs) (rs = 0.502, P <0.001) and iTILs (rs = 0.410, P < 0.001), respectively. PD-L1 expression status and TILs showed significant differences among molecular subtypes (P < 0.001), with the highest proportion of PD-L1+ and high TILs patients observed in the immunomodulatory (IM) subtype. TILs were significantly associated with RFS. Moreover, sTILs could act as an independent predictor of RFS (RR 0.953, 95â¯% CI 0.920 â¼ 0.987, P = 0.007), while PD-L1 expression status did not show the same prognostic significance. CONCLUSIONS: The incorporation of pre-treatment TILs and PD-L1 expression status as valuable tools for optimizing patient selection for immunotherapy and managing the risks associated with chemotherapy in Chinese TNBC patients. DATA AVAILABILITY: The data sets generated and analyzed during the current study are available from the corresponding author.
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The aim of this study was to evaluate the mutation spectrum of homologous recombination repair (HRR) genes and its association with tumor immune infiltration and prognosis in triple-negative breast cancer (TNBC). TNBC patients (434 patients from Ruijin cohort) were evaluated with targeted next-generating sequencing for mutations in HRR genes. The frequencies of mutations were compared with public reference cohorts (320 TNBC patients from METABRIC, 105 from TCGA, and 225 from MSKCC 2018). Associations between mutation status and tumor immune infiltration and prognosis were analyzed. HRR genes mutations were seen in 21.89% patients, with BRCA1/2 mutations significantly enriched in tumors with breast/ovarian cancer family history (P = 0.025) and high Ki-67 levels (P = 0.018). HRR genes mutations were not related with recurrence-free survival (RFS) (adjusted P = 0.070) and overall survival (OS) (adjusted P = 0.318) for TNBC patients, regardless of carboplatin treatment (P > 0.05). Moreover, tumor immune infiltration and PD-L1 expression was positively associated with HRR or BRCA1/2 mutation (all P < 0.001). Patients with both HRR mutation and high CD8+ T cell counts had the best RFS and OS, whereas patients with no HRR mutation and low CD8+ T cell counts had the worst outcomes (RFS P < 0.001, OS P = 0.019). High frequency of HRR gene mutations was found in early TNBC, with no prognostic significance. Immune infiltration and PD-L1 expression was positively associated with HRR mutation, and both HRR mutation and high CD8+ T cell infiltration levels were associated with superior disease outcome.
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Linfocitos Infiltrantes de Tumor , Mutación , Reparación del ADN por Recombinación , Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/inmunología , Neoplasias de la Mama Triple Negativas/mortalidad , Femenino , Pronóstico , Persona de Mediana Edad , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Reparación del ADN por Recombinación/genética , Adulto , Proteína BRCA1/genética , Antígeno B7-H1/genética , Anciano , Proteína BRCA2/genética , Biomarcadores de Tumor/genéticaRESUMEN
AIMS: Cytokeratin 5 (CK5) is a surrogate maker of progenitor cells and early glandular and myoepithelial cells (MECs) in the breast, and CK5 expression in breast MECs varies from ducts to lobules, and from normal to diseased tissue. However, the mechanisms underlying immunophenotypic alterations of CK5 expression in MECs remain unclear. METHODS: CK5 expression in MECs of 20 normal breast samples, 58 ductal carcinoma in situ (DCIS; including 21 DCIS with extensive lobular involvement), 11 atypical ductal hyperplasia (ADH), 18 non-invasive lobular neoplasia consisting of 11 atypical lobular hyperplasia (ALH) and 7 lobular carcinoma in situ (LCIS), 20 cystic lobules and 10 usual ductal hyperplasia (UDH) involving lobules were observed to evaluate the effects of contact with benign hyperplastic or cancerous luminal cells and pressure of dilated glands on CK5 expression. RESULTS: CK5 expression in normal ductal MECs was exclusively positive, whereas most normal lobular MECs were negative. In DCIS, cancerous ducts were primarily surrounded by CK5-positive MECs (91.0%), as were lobular acini involved by DCIS (89.2%), while the remaining normal acini maintained CK5-negative. CK5-positive MECs were found in 57.5% of acini in ALH and were more prevalent in LCIS (70.7%). CK5 expression was occasionally positive in both cystic lobules (16.7%) and lobules involved by UDH (14.3%), while an increase of CK5-positive MECs was found in ADH (38.2%). CONCLUSIONS: These results suggest that CK5 expression in lobular MECs may be altered by contact with cancerous luminal cells rather than benign hyperplastic luminal cells or pressure from dilated glands.
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Biomineralization of enzymes for in vivo diagnosis and treatment of diseases remain a considerable challenge, due to their severe reaction conditions and complicated physiological environment. Herein, we reported a biomimetic enzyme cascade delivery nanosystem, tumor-targeted erythrocyte membrane (EM)-cloaked iron-mineralized glucose oxidases (GOx-Fe0@EM-A) for enhancing anticancer efficacy by self-activated in vivo cascade to generate sufficient high toxic â¢OH at tumor site. Methods: An ultra-small Fe0 nanoparticle (Fe0NP) was anchored in the inner cavity of glucose oxidase (GOx) to form iron-mineralized glucose oxidase (GOx-Fe0) as a potential tumor therapeutic nanocatalyst. Moreover, erythrocyte membrane cloaking delivery of GOx-Fe0in vivo was designed to effectively accumulate ultra-small GOx-Fe0 at tumor site. Results: GOx-Fe0@EM-A had satisfactory biocompatibility and light-trigged release efficiency. Erythrocyte membrane cloaking of GOx-Fe0@EM-A not only prolongs blood circulation but also protects in vivo enzyme activity of GOx-Fe0; Tumor targeting of GOx-Fe0@EM-A endowed preferential accumulation at tumor site. After NIR light irradiation at tumor site, erythrocyte membrane of GOx-Fe0@EM-A was ruptured to achieve light-driven release and tumor deep penetration of ultra-small nanosize GOx-Fe0 by the photothermal effect of ICG. Then, GOx-Fe0 occurred self-activated in vivo cascade to effectively eradicate tumor by producing the highly cumulative and deeply penetrating â¢OH at tumor site. Conclusion: Tumor-targeted erythrocyte membrane-cloaked iron-mineralized glucose oxidase (GOx-Fe0@EM-A) exhibits a promising strategy for striking antitumor efficacy by light-driven tumor deep penetration and self-activated therapeutic cascade.
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Membrana Eritrocítica/efectos de los fármacos , Glucosa Oxidasa/metabolismo , Hierro/química , Animales , Biomimética , Biomineralización , Línea Celular Tumoral/metabolismo , Línea Celular Tumoral/efectos de la radiación , Modelos Animales de Enfermedad , Membrana Eritrocítica/enzimología , Membrana Eritrocítica/metabolismo , Femenino , Humanos , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Ratones , Ratones Endogámicos BALB C , Nanopartículas/química , Nanopartículas/uso terapéutico , Oligoelementos/química , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
PURPOSE: The tumor microenvironment has a profound impact on prognosis and immunotherapy. However, the landscape of the triple-negative breast cancer (TNBC) microenvironment has not been fully understood. EXPERIMENTAL DESIGN: Using the largest original multi-omics dataset of TNBC (n = 386), we conducted an extensive immunogenomic analysis to explore the heterogeneity and prognostic significance of the TNBC microenvironment. We further analyzed the potential immune escape mechanisms of TNBC. RESULTS: The TNBC microenvironment phenotypes were classified into three heterogeneous clusters: cluster 1, the "immune-desert" cluster, with low microenvironment cell infiltration; cluster 2, the "innate immune-inactivated" cluster, with resting innate immune cells and nonimmune stromal cells infiltration; and cluster 3, the "immune-inflamed" cluster, with abundant adaptive and innate immune cells infiltration. The clustering result was validated internally with pathologic sections and externally with The Cancer Genome Atlas and METABRIC cohorts. The microenvironment clusters had significant prognostic efficacy. In terms of potential immune escape mechanisms, cluster 1 was characterized by an incapability to attract immune cells, and MYC amplification was correlated with low immune infiltration. In cluster 2, chemotaxis but inactivation of innate immunity and low tumor antigen burden might contribute to immune escape, and mutations in the PI3K-AKT pathway might be correlated with this effect. Cluster 3 featured high expression of immune checkpoint molecules. CONCLUSIONS: Our study represents a step toward personalized immunotherapy for patients with TNBC. Immune checkpoint inhibitors might be effective for "immune-inflamed" cluster, and the transformation of "cold tumors" into "hot tumors" should be considered for "immune-desert" and "innate immune-inactivated" clusters.
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Genómica , Neoplasias de la Mama Triple Negativas/etiología , Neoplasias de la Mama Triple Negativas/patología , Escape del Tumor/genética , Escape del Tumor/inmunología , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología , Biomarcadores de Tumor , Biología Computacional/métodos , Variaciones en el Número de Copia de ADN , Femenino , Perfilación de la Expresión Génica , Genómica/métodos , Humanos , Inmunomodulación , Fenotipo , Pronóstico , Transducción de Señal , Neoplasias de la Mama Triple Negativas/mortalidadRESUMEN
BACKGROUND: Triple-negative breast cancers (TNBCs) are a group of heterogeneous diseases with various morphology, prognosis, and treatment response. Therefore, it is important to identify valuable biomarkers to predict the therapeutic response and prognosis for TNBCs. Tumor-infiltrating lymphocytes (TILs) may have predictive value to pathological complete response (pCR) in neoadjuvant treated TNBCs. However, absence of standardized methodologies for TILs measurement has limited its evaluation and application in practice. In 2014, the International TILs Working Group formulated the recommendations of pathologic evaluation for TILs in breast cancers. METHODS: To evaluate the predictive value of TILs scored by methods recommended by International TILs Working Group 2014, we performed a retrospective study of TILs in 166 core needle biopsy specimens of primary invasive TNBCs with neoadjuvant chemotherapy (NAC) in a Chinese population. Intratumoral TILs (iTILs) and stromal TILs (sTILs) were scored respectively. The associations between TILs and pCR were analyzed. RESULTS: Both sTILs (p = 0.0001) and iTILs (P = 0.001) were associated with pCR in univariate logistic regression analysis. Multivariate logistic regression analysis indicated that both sTILs (P = 0.006) and iTILs (P = 0.04) were independent predictors for pCR. Receiver operating characteristics (ROC) curve analysis was used to identify the optimal thresholds of TILs. TNBCs with more than 20% sTILs (P = 0.001) or with more than 10% iTILs (P = 0.003) were associated with higher pCR rates in univariate analysis. Multivariate analysis showed that a 20% threshold of sTILs (P = 0.005) was an independent predictive factor for pCR. CONCLUSIONS: Our study indicated that TILs scored by recommendations of International TILs Working Group 2014 in pre-NAC core needle biopsy specimens was significantly correlated with pCR in TNBCs, higher TILs scores predicting higher pCR rate. Both sTILs and iTILs were independent predictors for pCR in TNBCs. A 20% threshold for sTILs may be feasible to predict pCR to NAC in TNBCs.
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Biomarcadores de Tumor/análisis , Linfocitos Infiltrantes de Tumor/patología , Valor Predictivo de las Pruebas , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama Triple Negativas/terapia , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Femenino , Humanos , Persona de Mediana Edad , Terapia Neoadyuvante , Pronóstico , Curva ROC , Estudios Retrospectivos , Neoplasias de la Mama Triple Negativas/diagnósticoRESUMEN
PURPOSE: The characteristic expression of DNA damage response proteins in familial breast cancers with BRCA1, BRCA2, or non-BRCA1/2 mutations has not been analyzed in Chinese patients. Our study aimed to assess the differential expression of microcephalin 1 (BRIT1), ATM serine/threonine kinase (ATM), checkpoint kinase 2 (CHEK2), BRCA1, RAD51 recombinase (RAD51), and poly (ADP-ribose) polymerase 1 (PARP-1) and establish the profile of Chinese familial breast cancers with different mutation status. METHODS: We constructed five tissue microarrays from 183 familial breast cancer patients (31 with BRCA1 mutations; 14 with BRCA2 mutations, and 138 with non-BRCA1/2 mutations). The DNA response and repair markers used for immunohistochemistry analysis included BRIT1, ATM, CHEK2, BRCA1, RAD51, and PARP-1. The expressions of these proteins were analyzed in BRCA1/2 mutated tumors. The association between pathologic characteristics with BRCA1/2 mutation status was also analyzed. RESULTS: In familial breast cancer patients, BRCA1 mutated tumors were more frequent with high nuclear grade, estrogen receptor/progesterone receptor/human epidermal growth factor receptor 2 negative, low Ki-67, and positive CK5/6. BRCA1 mutated tumors had lower CHEK2 and higher cytoplasmic BRIT1 expression than BRCA2 and non-BRCA1/2 mutation tumors. BRCA2-associated tumors showed higher CHEK2 and cytoplasmic RAD51 expression than those in other groups. Nuclear PARP-1 expression in BRCA1/2-associated tumors was significantly higher than in non-BRCA1/2 mutation tumors. Moreover, we found quite a few of negative PARP-1 expression cases in BRCA1/2 mutated groups. CONCLUSION: The clinicopathologic findings of BRCA1-associated Chinese familial breast cancers were similar to the results of other studies. Chinese familial breast cancer patients with BRCA1/2 mutations might have distinctive expression of different DNA damage response proteins. The reduced expression of PARP-1 in Chinese BRCA1/2 mutated breast cancer patients could influence the therapeutic outcome of PARP-1 inhibitors.
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In order to investigate clinicopathological characteristics and prognosis of mixed invasive ductal and lobular carcinoma (IDC-L), 209,109 primary breast cancer patients diagnosed with invasive ductal carcinoma (IDC), invasive lobular carcinoma (ILC) or IDC-L were included. It was found that IDC-L patients had lower tumor grade and higher hormone receptor positive proportions than IDC patients. Moreover, IDC-L patients were younger and had a similar hormone receptor status compared with ILC patients. Kaplan-Meier plots showed that the breast cancer-specific survival (BCSS) of IDC-L patients was significantly better than IDC patients (P < 0.001) and tended to be better than ILC patients (P = 0.166). However, after adjusting for clinicopathological factors, survival advantage of IDC-L disappeared. Subgroup analysis indicated that IDC-L had higher hazard ratios (HRs) than IDC in grade 1, grade 2, ER-positive and ER-negative subgroups. Survival analysis in ER-positive and ER-negative subgroups showed that IDC-L predicted a worse prognosis than IDC. In conclusion, IDC-L is a distinct histological subtype compared with IDC and ILC. Lower grade and higher ER-positive proportions mainly contribute to its better prognosis. In both ER-positive and ER-negative subgroups, IDC-L predicts worse prognosis than IDC, which suggested the inadequacy of IDC-based therapy and the need of escalated therapy.
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Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Carcinoma Lobular/patología , Receptores de Estrógenos/metabolismo , Neoplasias de la Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Lobular/metabolismo , Femenino , Humanos , Clasificación del Tumor , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Análisis de SupervivenciaRESUMEN
Tumor-infiltrating lymphocytes (TILs) may be associated with clinical outcome in triple-negative breast cancers (TNBCs). However, lacking of standardized methodologies in TILs evaluation has hindered its application in clinical practice. To evaluate the prognostic role of TILs scored by methods recommended by International TILs Working Group 2014, we performed a retrospective study of TILs in 425 primary invasive TNBCs in a Chinese population with a median follow-up of 4 years. Intratumoral TILs (iTILs) and stromal TILs (sTILs) were scored respectively. The associations between TILs and disease-free survival (DFS), distant disease-free survival (DDFS) and overall survival (OS) were evaluated with COX models. ITILs were not associated with prognosis. Higher sTILs were associated with better prognosis; for every 10% increase in sTILs, a 5% reduction of risk of recurrence or death (P < 0.001), 5% reduction of risk of distant recurrence (P < 0.001), and 4% reduction of risk of death (P = 0.002) were observed. Multivariate analysis confirmed sTILs to be an independent prognostic marker. 3.5% of TNBCs had more than 50% lymphocytes (lymphocyte-predominant breast cancer, LPBC), and associations between LPBC status and prognosis were observed but did not reach statistical significance. TNBCs with more than 20% sTILs had a significantly better prognosis than the patients with no more than 20% sTILs. In conclusion, our study indicated that sTILs scored by methods recommended by International TILs Working Group 2014 were associated with the prognosis of TNBCs. STILs could be an independent prognostic biomarker in TNBCs, increasing sTILs predicting better prognosis.
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Linfocitos Infiltrantes de Tumor/inmunología , Neoplasias de la Mama Triple Negativas/inmunología , Femenino , Humanos , Linfocitos Infiltrantes de Tumor/patología , Persona de Mediana Edad , Pronóstico , Neoplasias de la Mama Triple Negativas/patologíaRESUMEN
Elevated plasma levels of homocysteine have been implicated in neurodevelopmental and neurodegenerative disorders in human studies. Although the molecular mechanisms underlying the effects of homocysteine (Hcy) cytotoxicity on the nervous system are not yet fully unknown, induction of DNA interstrand cross-links and inhibition of neural stem cells (NSCs) survival may be involved. The objective of our study was to investigate the effects of Hcy on DNA interstrand cross-links in NSCs, and to explore its possible mechanisms. We also found that Hcy induced cell DNA damage on a dose-dependent manner and evoked reactive oxidative species (ROS) production, leading to elevated apoptosis in NSCs. Moreover, Hcy exposure activated the Fanconi anemia (FA) pathway, which was characterized by increases in monoubiquitination of Fanci and Fancd2 and enhancement of the interaction between above two proteins. On contrary, N-Acety-l-Cysteine (NAC) decreased Hcy-evoked ROS production and significantly ameliorated DNA damage and improved cell survival. These data suggest that Hcy may play a role in the pathogenesis of neurological diseases via a molecular mechanism that induces DNA interstrand cross-links via oxidative stress and involves in negative regulation of NSCs survival.
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Daño del ADN , Homocisteína/toxicidad , Células-Madre Neurales/efectos de los fármacos , Animales , Apoptosis , Línea Celular , Supervivencia Celular , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/metabolismo , Proteínas del Grupo de Complementación de la Anemia de Fanconi/metabolismo , Homocisteína/metabolismo , Ratones , Células-Madre Neurales/citología , Especies Reactivas de Oxígeno/metabolismo , UbiquitinaciónRESUMEN
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.