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1.
Pregnant women were classified according to their serological status for cytomegalovirus, herpes simplex virus or rubella virus. Lymphocytes taken from non-pregnant women were shown to be able to recognise viral antigens and the mitogen phytohaemagglutinin by the measurement of proliferative responses and by the production of gamma interferon. Proliferative responses or gamma interferon production were greatly reduced in the presence of plasma taken during the first, second or third trimester and immediately post-partum. The responses then gradually returned to normal after delivery. The availability of serial sera taken before pregnancy as well as during and after pregnancy in individual women showed that this effect was maintained even when sera had been stored frozen for more than one year. Mixing experiments were performed to vary the proportion of pregnancy serum in any particular assay but this did not prove that pregnancy sera were actively suppressive. Instead, the data suggest that pregnancy sera are deficient in some factor or factors which are required to support lymphocyte proliferation. The effect was not attributable to the physiological haemodilution of pregnancy leading to a reduced concentration of putative factors nor could transferrin levels or the iron binding capacity of this protein be implicated.  相似文献   

2.
Abstract Serial blood samples were collected during pregnancy, after delivery and several months postnatally from 28 women. The blastogenic responses of lymphocytes to varying concentrations of phytohaemagglutinin (PHA) were tested using autologous plasma or fetal calf serum (FCS) to support the lymphocyte cultures. Using FCS, the blastogenic response decreased as pregnancy progressed and remained depressed months after delivery. In contrast, when autologous plasma was used a 10-fold higher concentration of PHA was required to give optimal stimulation. Blastogenic responses were still suppressed during pregnancy but had returned to initial values by the time of delivery and were greater still in the post-partum and postnatal periods. We conclude that the inherent ability of lymphocytes to undergo blastogenesis is suppressed during pregnancy but that this is overshadowed by a humoral effect of pregnancy plasma. The significance of these results is discussed.  相似文献   

3.
Abstract Heat-killed Neisseria meningitidis was found to be mitogenic for human peripheral blood lymphocytes (PBL). Separation of lymphocytes by rosetting with sheep erythrocytes indicated that both rosette-forming cells (E+, T-enriched) and nonrosetting cells (E, B-enriched) were induced to proliferate by the bacteria. Following meningococcal stimulation, E cells and PBL displayed proliferative responses of similar magnitude and followed essentially the same kinetics with peak responses occurring after 3–4 days of culture. By comparison, E+ lymphocytes gave significantly higher responses and required a longer incubation period (5–7 days) to reach maximum levels of proliferative activity.  相似文献   

4.
Indoleamine 2,3 dioxygenase and regulation of T cell immunity   总被引:11,自引:0,他引:11  
Regulation of adaptive immune responses is critically important to allow the adaptive immune system to eradicate infections while causing minimal collateral damage to infected tissues, as well as preventing autoimmune disease mediated by self-reactive lymphocytes. Tumors and pathogens that cause persistent infections can subvert immunoregulatory processes to protect themselves from destruction by T cells, to the detriment of patients. A growing body of evidence supports the hypothesis that specialized subsets of dendritic cells expressing indoleamine 2,3 dioxygenase (IDO), which catalyzes oxidative catabolism of tryptophan, play critical roles in regulation of T cell-mediated immune responses. IDO-dependent T cell suppression by dendritic cells suggests that biochemical changes due to tryptophan catabolism have profound effects on T cell proliferation, differentiation, effector functions, and viability. This has critical implications for immunotherapeutic manipulations designed for patients with cancer and chronic infectious diseases. In this review, I focus on dendritic cells that can express IDO, and which acquire potent T cell regulatory functions as a consequence.  相似文献   

5.
《Cytokine》2014,65(2):175-183
Aneuploidy, a condition associated with altered chromosome number, hence DNA index, is frequently seen in many diseases including cancers and affects immunity. Iron, an essential nutrient for humans, modulates the immune function and the proliferation of normal and cancer cells. To determine whether impaired immunity seen in iron-deficient subjects may be related to aneuploidy, we measured spleen cell DNA index, percent of cells in different phases of the cell cycle, plasma and/or supernatant IL-2, IL-10, IL-12, and interferon-gamma in control, pair-fed, iron-deficient, and iron-replete mice (N = 20–22/group). The test and control diets differed only in iron content (0.09 mmol/kg versus 0.9 mmol/kg) and were fed for 68 days. Mean levels of hemoglobin and liver iron stores of iron-deficient and iron-replete mice were 40–60% lower than those of control and pair-fed mice (P < 0.05). Mean plasma levels of IL-10, interferon-gamma and percent of cells in S + G2/M phases were lower in mice with than in those without aneuploidy (P < 0.05). Lowest plasma IL-12 and interferon-gamma concentrations were observed in iron-deficient mice with aneuploidy. Mean percents of cultures with aneuploidy and DNA indexes were higher in iron-deficient and iron-replete than in control and pair-fed mice likely due to delayed cell division (P < 0.05). Aneuploidy decreased the concentration of IL-2 and interferon-gamma in baseline cultures while it increased that of interferon-gamma in anti-CD3 treated cultures. Aneuploidic indexes negatively correlated with cytokine levels, percents of cells in S + G2/M phases and indicators of iron status (P < 0.05). Although chromosome cytogenetics was not performed, for the first time, we report that increased aneuploidy rate may modulate the immune function during iron-deficiency.  相似文献   

6.
Partial suppression of cell mediated immunity in chromoblastomycosis   总被引:2,自引:0,他引:2  
The cellular immune response of 8 patients from the Brazilian Amazon region with chromoblastomycosis was analyzed. Primary immunological responses of patients were tested by contact sensitization to 2,4-dinitro-chlorobenzene (DNCB), or rejection of first set skin allografts. 2 of 8 patients were reactive to DNCB after sensitization, and skin allograft rejection occured in an average of 14 days. Capacity of patients to mount recall immunological responses was measured by skin testing with two fungal antigens and three bacterial antigens. Delayed skin reaction to trichophytin and Candida antigens was negative in the majority of the patients. However, reactivity to mycobacterial (tuberculin), and bacterial (staphylococcal, streptococcal) antigen was high, or only slightly diminished respectively. The data suggest that patients with chromoblastomycosis have suppressed nonspecific, cell mediated immunity for some antigens (skin allografts, DNCB, fungal antigens), while reactivity to bacterial and mycobacterial antigens is not impaired.  相似文献   

7.
8.
Many viruses regulate a crucial point in the apoptotic pathway by expressing viral Bcl-2 homologues, which have become useful tools to investigate the mechanisms behind the control of the mitochondrial checkpoint of apoptosis. Concurrently, a number of viral inhibitors of innate immune signalling have been instrumental tools in the discovery of key host pathways. Here we discuss how viral inhibitors of the apoptotic and innate signalling pathways have further enhanced the understanding of both research fields and are beginning to shed light on how these two pathways converge.  相似文献   

9.
Naturally occurring maternal immunosuppression increases the risk of infection by a variety of pathogens during pregnancy and the postpartum period. Pulmonary cryptococcosis during pregnancy is relatively rare. Here, we report on two cases of pulmonary cryptococcosis during pregnancy and puerperium. Both cases were successfully treated using oral fluconazole after parturition to avoid fetal toxicity. For the two patients, the placentas were checked and found to be pathologically normal, and the cryptococcal serum antigen in both infants was negative. Pulmonary cryptococcosis should be considered during differential diagnosis as a possible cause of abnormal chest shadow in pregnant patients.  相似文献   

10.
To clarify the mechanism of reactivation of cytomegalovirus (CMV) in pregnancy, cell mediated immunity to CMV was investigated in 108 pregnant and 29 postpartal women employing the leukocyte migration inhibition technique. It was demonstrated that CMV-specific cell mediated immunity was suppressed as gestation progressed in 20% of the seropositive women during the first trimester, in 78% during the second trimester and in all at term. The suppression of cell mediated immunity during pregnancy ceased 8 weeks after parturition. The results suggested that reactivation of CMV in pregnancy was probably caused by the suppression of CMV-specific cell mediated immunity.  相似文献   

11.
Osei-Kumah A  Smith R  Clifton VL 《Cytokine》2008,43(2):187-193
The mechanisms contributing to worsening of asthma during pregnancy have not been well characterized. Both asthma and pregnancy are conditions associated with a skewing of the immune response from T helper (Th) 1 toward a Th2 response. We hypothesise that worsening of asthma during pregnancy may be due to an enhanced production of circulating proinflammatory cytokines and chemokines and this may be modified by the use of inhaled glucocorticoid treatment. Peripheral blood was collected from asthmatic (n = 35) and control non-asthmatic patients (n = 13) in the third trimester (30–37 weeks) of pregnancy. Fetal blood was collected from the umbilical vein of the placenta after delivery from normal (n = 24) and pregnancies complicated by asthma (n = 24). Plasma samples were assayed for IL-6, -8, eotaxin and RANTES using conventional ELISA. In addition, a range of Th1 and Th2 cytokines measured using Luminex system. There were no significant differences in the levels of maternal IL-6, IL-8, eotaxin and RANTES between asthmatics and nonasthmatics. The results of this study suggest that the presence of asthma does not result in an enhanced circulation of Th2 related cytokines and chemokines during the third trimester of pregnancy. Furthermore peripheral blood cytokine concentrations appear unaffected by inhaled glucocorticoid treatment. Cord plasma eotaxin concentrations were increased in pregnancies complicated by asthma, compared with control. This is the first study to show increased eotaxin production in the feto-placental unit of asthmatic pregnancies and may be one mechanism by which allergy susceptibility is increased in the offspring of asthmatic women.  相似文献   

12.
Phagocytic index and rosette test E have been determined in 50 patients, including 15 with diffuse peritonitis and the noncomplicated diffuse peritonitis, 20 patients with septic complications, and 15 patients who underwent abdominal surgery. It was found, that phagocytic index is decreased in all patients after abdominal surgery. The most marked decrease of this index was found in patients with complicated peritonitis. It still decreases in the course of peritonitis and increases in the reference group. The marked decrease in the number of T-cells was observed in complicated peritonitis during the whole period of follow-up while it normalizes in case of noncomplicated peritonitis as in the reference group. Using the tests under study it was possible to assess cell-mediated immunity which is depressed in peritonitis. The tests enable also the prediction of septic complications of peritonitis.  相似文献   

13.
Changes in coagulation parameters depending on reproductive status and pregnancy have been previously reported in both human and other veterinary species. The objective of this study was to determine if different reproductive status affects coagulation parameters in queens. Blood samples from 66 queens submitted to spay surgery were obtained. A hemostatic panel including platelet count, prothrombin time, activated partial thromboplastin time, fibrinogen concentration, and D-dimer and also progesterone concentrations were measured before surgery. According to progesterone results and embryo vesicles diameter, four groups were established: (1) nonpregnant queens with low (≤1 ng/mL) progesterone concentration (LP) (n = 33); (2) nonpregnant queens with high (≥2 ng/mL) progesterone concentration (n = 8) (HP); (3) first half of pregnancy (n = 12); and (4) second half of pregnancy (n = 13). None of the evaluated parameters showed statistically significant differences among the different groups. There was no significant linear correlation between progesterone values and coagulation parameters. In conclusion, neither the presence of the embryo nor the higher values of progesterone concentration induced statistically significant changes in the coagulation profile studied.  相似文献   

14.
Dinitrofluorobenzene (DNFB) contact-sensitivity test and leucocyte adherence inhibition (LAI) test were performed in this study as in vivo and in vitro tests to measure the cell-mediated immunity (CMI) in chickens subjected to stimulation of reticuloendothelial (RE) system, depletion of RE system and other experimental groups after being challenged with Marek's disease (MD) virus. It was found that CMI was lower in the birds with depleted RE system and infected control birds, whereas CMI was higher in the birds with activated RE system and vaccinated birds as revealed by DNFB contact-sensitivity test. In cases of LAI test, the number of LAI-positive birds were highest in the chicks with depleted RE system particularly in 3rd and 4th month of age, when the incidence of MD was also maximum.  相似文献   

15.
 The human mucin, MUC-1, is a transmembrane glycoprotein that is produced by both normal an malignant epithelium. The MUC-1 produced by malignant epithelium is underglycosylated, which leads to the expression by tumors of novel T and B cell epitopes on the mucin polypeptide core. Similar underglycosylation occurs in the lactating breast. In this report, we describe a long-term survivor of breast cancer whose tumor strongly expressed the T- and B-cell-stimulatory epitopes. Five years after presenting with the tumor, the patient had her first pregnancy, at which time she developed fulminant lymphocytic mastitis. We demonstrate that the lactating breast produced mucin expressing the same “tumor-specific” epitopes as the original cancer. The patient had circulating anti-mucin antibodies of both the IgM and IgG isotypes (these are not found in normal controls), and mucin-specific cytotoxic T lymphocytes in the peripheral blood. Limiting  –  dilution analysis for mucin  –  specific cytotoxic T lymphocytes in three different experiments yielded frequencies of 1 in 3086, 1 in 673, and 1 in 583, compared to approximately 1 in 106 in normal controls. The patient remains clinically free of carcinoma after 5 additional years of follow-up. We propose that the original tumor primed the patient’s immune response against the mucin epitopes, and that the re-expression of these epitopes on the lactating breast evoked a secondary immune response. It is tempting to speculate that the vigor of her anti-mucin immunity may have helped protect this patient against recurrent tumor. Received: 12 February 1996 / Accepted: 5 November 1996  相似文献   

16.

Background

Ubiquitin Specific Peptidase 39 (USP39) is a 65 kDa SR-related protein involved in RNA splicing. Previous studies showed that USP39 is related with tumorigenesis of human breast cancer cells.

Results

In the present study, we investigated the functions of USP39 in human hepatocellular carcinoma (HCC) cell line SMMC-7721. We knocked down the expression of USP39 through lentivirus mediated RNA interference. The results of qRT-PCR and western blotting assay showed that both the mRNA and protein levels were suppressed efficiently after USP39 specific shRNA was delivered into SMMC-7721 cells. Cell growth was significantly inhibited as determined by MTT assay. Crystal violet staining indicated that colony numbers and sizes were both reduced after knock-down of USP39. Furthermore, suppression of USP39 arrested cell cycle progression at G2/M phase in SMMC-7721cells. In addition, Annexin V showed that downregulation of USP39 significantly increased the population of apoptotic cells.

Conclusions

All our results suggest that USP39 is important for HCC cell proliferation and is a potential target for molecular therapy of HCC.

Electronic supplementary material

The online version of this article (doi:10.1186/s40659-015-0006-y) contains supplementary material, which is available to authorized users.  相似文献   

17.
Abstract

Previously, the authors have reported seasonal variations in cell mediated immunity in the dog during the period July, 1977 ‐ October 1978 as measured by whole blood lectin‐induced lymphocyte transformation. Peak activity occurred in the summer, suggesting association with photoperiodicity. Here the authors report on immune response of dogs kept indoors ‐ under controlled physical environment ‐ with a natural (outdoor) photoperiod or under a 12:12 h (LD) regime, and a control group kept in outdoor kennels. Peak immune activity in 1979 occurred in the winter, in both indoor groups as well as the outdoor groups subject to natural photoperiod. Since the indoor dogs were kept at a constant temperature and humidity in clean (filtered) air, photoperiod, temperature, and particulate air contaminants probably are not associated with seasonal variations in immunity. The underlying cause for either the seasonal variations or the shift from peak activity in the summer of 1978 to winter of 1979 is unknown. Dogs under LD = 12:12 light regime had a significantly lowered immunity relative to the dogs with the natural photoperiod.  相似文献   

18.
Delayed-type hypersensitivity (DTH) is a cell-mediated immune response that can be adoptively transferred in rats when greater than 2 X 10(8) cells from peritoneal exudate, lymph nodes, or spleen are used. We have shown that by using an in vitro conditioning step with antigen, transfer can be subsequently carried out with as few as 2 X 10(7) spleen cells. The magnitude of DTH was reflected in ear swelling after intradermal injection of antigen [tuberculin or keyhole limpet hemocyanin (KLH)] and confirmed histologically. The transfer was antigen specific, requiring the sensitizing antigen in both the in vitro conditioning step and in the ear test challenge. Adoptive transfer with conditioned cells was genetically restricted by alleles of the RT-1 region [major histocompatibility complex (MHC) of the rat]. Brown Norway strain (n haplotype) immune cells would not transfer DTH to Lewis (1 haplotype), ACI (a haplotype), or Buffalo (b haplotype) rats, whereas each strain would transfer DTH to syngeneic recipients. Moreover, this pattern of restriction held for all strains when tested in reciprocal fashion. In additional experiments, F1 to parental bone marrow chimeras were constructed so that bone-marrow-derived cells and non-bone-marrow-derived cells were of different RT-1 haplotypes. When these chimeras were used as recipients, transfer of DTH was only observed when immune donor cells and recipient non-bone-marrow-derived cells were syngeneic. These results point to the critical role of non-bone-marrow-derived cells (endothelial cells) in the DTH reaction.  相似文献   

19.
Clustered regularly interspaced short palindromic repeats (CRISPR)‐encoded immunity in Type I systems relies on the Cascade (CRISPR‐associated complex for antiviral defence) ribonucleoprotein complex, which triggers foreign DNA degradation by an accessory Cas3 protein. To establish the mechanism for adaptive immunity provided by the Streptococcus thermophilus CRISPR4‐Cas (CRISPR‐associated) system (St‐CRISPR4‐Cas), we isolated an effector complex (St‐Cascade) containing 61‐nucleotide CRISPR RNA (crRNA). We show that St‐Cascade, guided by crRNA, binds in vitro to a matching proto‐spacer if a proto‐spacer adjacent motif (PAM) is present. Surprisingly, the PAM sequence determined from binding analysis is promiscuous and limited to a single nucleotide (A or T) immediately upstream (?1 position) of the proto‐spacer. In the presence of a correct PAM, St‐Cascade binding to the target DNA generates an R‐loop that serves as a landing site for the Cas3 ATPase/nuclease. We show that Cas3 binding to the displaced strand in the R‐loop triggers DNA cleavage, and if ATP is present, Cas3 further degrades DNA in a unidirectional manner. These findings establish a molecular basis for CRISPR immunity in St‐CRISPR4‐Cas and other Type I systems.  相似文献   

20.
Epithelial cancer cells secrete mucins carrying carbohydrate antigens such as a sialyl-Tn antigen into cancer tissues and/or the bloodstream, in which mucins may interact with CD22 (Siglec-2). Mucins isolated from colon cancer cells and bovine submaxillary mucins bound to CD22 cDNA transfectants and a human B cell line, Daudi cell, and the binding of soluble recombinant CD22 to the mucins was confirmed by means of a plate assay. The binding specificity was demonstrated by the fact that the mucins bound to the recombinant CD22 with an intact ectodomain but not to that with a mutated ectodomain. Daudi cells were stimulated with anti-IgM F(ab′)2 in the presence or absence of mucins. Ligation of mucins to CD22 decreased the phosphorylation of CD22 and SHP-1 recruitment, and the phosphorylation of ERK-1/2 prominently. The in vivo effect of mucins on splenic B cells in the tumor-bearing state was investigated using mucin-producing (TA3-Ha) and non-producing (TA3-St) mammary adenocarcinoma-bearing mice. When fluorescence-labeled epiglycanins were administered to normal mice, a portion of them was taken up by the spleen and became associated with splenic B cells. We found that splenic B cells were reduced in TA3-Ha-bearing mice but not in TA3-St-bearing ones. These results suggest that in the tumor-bearing state a portion of the mucins in the bloodstream was taken up by the spleen and ligated to CD22 expressed on splenic B cells, which may have led to down-regulation of signal transduction.  相似文献   

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