A lack of clinical correlation between the presence of HHV-8 DNA in PBMCs and staging of Kaposi's sarcoma.
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DNA, Viral↗
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Is there a market for PBMCs (pharmacy benefit management company) abroad?
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Canada↗
[Cloning and expression of full-length subtype E and subtype B gag gene from uncultured PBMCs of HIV-1 infected individuals in China].
OBJECTIVE: To clone and express subtype E and subtype B gag gene of the prevalent HIV-1 strain in China. METHODS: One HIV-1 positive sample, whose subtype had been determined as sub-type E and one HIV-1 positive sample, whose subtype had been determined as subtype B by sequence analysis of partial env gene were chosen to be amplified by nested PCR. We got two full-length fragments of gag gene and incorporated them first into plin8Pr55 and then into pFastBacl. RESULTS: Sequence analysis showed the cloned gag genes have the complete open-reading frames and have no major deletion and insertion. Using the Bac-toBac system, we obtained the recombinant baculoviruses containing gag genes. Western-blot analysis showed that insect cells infected with gag recombinant baculoviruses expressed HIV-1 gag antigen. Thin section electron microscopy showed that virus-like particles (VLPs) formed in insect cells was infected with gag. CONCLUSIONS: The cloning and expression of gag genes of the prevalent HIV-1 stains in China revealed that the cloned genes have intact structure and function and this paves the way for the development of HIV-1 vaccines targeted at the epidemic of HIV-1 in China, also for the study of biological functions of gag gene and development of diagnostic kits of HIV-1.
Animals↗
Low density lipoprotein receptor determination in peripheral blood mononuclear cells (PBMCs). I. Influence of differences in cell concentration.
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Humans↗
Phenotypic analysis of PBMCs from uterine cervix cancer patients with high natural killer activity.
Phenotypic analysis of peripheral blood mononuclear cells from uterine cervix cancer patients, with increased natural killer cell activity, treated with radiation therapy was carried out. An increase in the percentage of CD56+ cells was observed in 5 out of 7 patients. When the expression of CD69, a phenotypic marker of cellular activation, was analyzed in 6 patients, an increase was observed in 4 of them. No direct correlation between cytolytic activity and the levels of CD56+ or CD69+ cells were observed. After 72 hr, an increased expression of CD56 was observed in 3 patients and a similar picture was seen at the same time following activation with IL-2 or IFN.
Adult↗
Effects of the temperature, the duration of frozen storage, and the freezing container on in vitro measurements in human peripheral blood mononuclear cells.
BACKGROUND: Bone marrow, peripheral blood, and umbilical cord blood have been used to prepare autologous and allogeneic pluripotential mononuclear cells for use in the repopulation of bone marrow. STUDY DESIGN AND METHODS: The purpose of this study was to evaluate how the temperature and duration of frozen storage of human peripheral blood mononuclear cells (PBMCs), as well as the freezing container, affected the in vitro recovery and viability of the mononuclear cells and their growth in colony-forming unit-granulocytic-erythroid-monocytic-megakaryocytic (CFU-GEMM) tissue culture assay. PBMCs were isolated from ficoll-hypaque-treated cellular residue obtained during the plateletpheresis of blood from 15 healthy donors. The PBMCs were treated with dimethyl sulfoxide (DMSO) to achieve a final DMSO concentration of 10 percent. Each unit was then separated into six aliquots: one stored in a polyvinylchloride (PVC) plastic bag, one in a polyolefin plastic bag, and four in polyethylene cryostorage vials. Each aliquot was frozen in a -80 degrees C mechanical freezer at a freezing rate of 2 to 4 degrees C per minute. The frozen PBMCs in PVC bags were stored in a -80 degrees C mechanical freezer and those in polyolefin bags in a -135 degrees C mechanical freezer. Each of the four frozen samples in a vial was stored at a different temperature: one in the -80 degrees C freezer, one in the -135 degrees C freezer, one in the vapor phase of liquid nitrogen at -150 degrees C, and one in liquid nitrogen at -197 degrees C. Some of the frozen PBMCs were stored for periods of 1 to 1.5 years and others for 2 to 2.4 years, after which they were thawed, washed, and tested. RESULTS: The samples stored in PVC bags and those stored in polyolefin bags exhibited in vitro recoveries that were 90 percent of the recovery of fresh PBMCs and viabilities of 90 percent after 2.4 years of frozen storage. The PBMCs stored in PVC bags exhibited no loss of CFU-GEMM activity after 1 to 1.5 years, but a 40-percent loss of activity was observed after 2 to 2.4 years. PBMCs stored in polyolefin bags, however, exhibited no loss of CFU-GEMM activity, even after 2 to 2.4 years of storage. In vitro recovery was significantly lower in PBMCs stored in vials at -80 degrees C or -135 degrees C than in cells stored in PVC or polyolefin bags at these temperatures, both in the 1- to 1.5-year and the 2- to 2.4-year time frames. In vitro recovery and viability were similar in PBMCs stored in vials at -80 degrees C, -135 degrees C, -150 degrees C, and -197 degrees C. The growth patterns in the CFU-GEMM assay in PBMCs stored in vials were significantly lower after storage at -80 degrees C than after storage at -135 degrees C, -150 degrees C, or -197 degrees C. CONCLUSION: PBMCs isolated by leukapheresis and ficoll-hypaque treatment can be frozen with 10-percent DMSO in a -80 degrees C mechanical freezer. When a PVC bag is used for freezing and storage of PBMCs at -80 degrees C, the duration of frozen storage should not exceed 1.5 years, whereas PBMCs frozen in a polyolefin bag can be stored in a -135 degrees C freezer for as long as 2.4 years. When these guidelines were followed, in vitro recovery was 90 percent that of fresh PBMCs, viability was 90 percent, and growth in the CFU-GEMM tissue culture assay was similar to that of fresh PBMCs. The PBMCs frozen and stored in PVC or polyolefin bags exhibited satisfactory results, whereas those stored in cryostorage vials did not.
Blood Preservation↗
[Clinical significance of detecting neonatal peripheral blood mononuclear cells infected by HBV].
OBJECTIVE: To understand the HBV infection rate of peripheral blood mononuclear cells (PBMCs) from fetuses of HBsAg positive mothers, associated risk factors and to explore the clinical significance of detecting HBV infected PBMCs. METHODS: Sixty eight pregnant women who were delivered at the First Hospital of Xi'an Jiaotong University, China from August 1995 to February 1997, and their newborns were studied. They were divided into two groups according to their status of HBV serological markers. The study group included 50 cases who were serum HBsAg positive and 18 cases without any HBV serum markers served as control group. All these cases had no symptoms of hepatitis, high risk premature labor, premature delivery and hypertensive disorder complicating pregnancy. Age and gestational age were matched in two groups. Blood samples (5 mL) were taken from the peripheral vein of pregnant women before delivery and from newborns within 24 h after birth, before inoculation of HBV vaccine (HBVac) and injection of hepatitis B immunoglobulin (HBIG). PBMCs were isolated. The sera and PBMCs were stored at -80 degrees C. HBV-DNA in serum and PBMCs were detected with nested polymerase chain reaction (n-PCR). Two pairs of oligonucleotide primers, the outer primer pair for first PCR and inner primer pair for second PCR, designed according to region S of HBV genome were synthesized by Shanghai Cell Biology Institute of Chinese Academy of Science. RESULTS: The detection rate of HBV-DNA in serum and PBMCs from HBsAg positive pregnant women was 60.0% (30/50) and 40.0% (20/50), respectively. The detection rate of HBV-DNA in serum and PBMCs from newborns of HBsAg positive pregnant women was 46.0% (23/50) and 30.0% (15/50), respectively. Ten newborns were HBV-DNA positive in serum only, 2 were positive in PBMCs only and 13 were positive in both serum and PBMCs. In the control group, HBV-DNA was not detected in PBMC nor in serum. The positive rate of HBV-DNA in PBMCs of newborns was significantly higher in the group of mothers who were HBV-DNA or HBeAg positive in serum (P < 0.05, P < 0.01); the positive rate was significantly higher in the group of mothers who were HBV-DNA positive in both serum and PBMC than that in the group of mothers who were serum HBV-DNA positive only (P < 0.01); and it was markedly higher in the group of mothers who were PBMC HBV-DNA positive than that in group of mothers who were HBV-DNA negative in PBMCs (P < 0.01). The positive rate of HBV-DNA in PBMCs of newborns was significantly higher in the group of newborns who were HBV-DNA positive in serum than that in the group of newborns who were HBV-DNA negative in serum (P < 0.05). CONCLUSIONS: The positive rate of HBV-DNA in PBMCs from newborns of HBsAg positive pregnant women was 30.0% (15/30). It was related to HBV viremia level and HBV-DNA status in PBMCs of mothers and newborns. Detection of HBV-DNA in PBMCs may be an important supplementary method to determine intrauterine HBV infection, and can predict the response to HBV vaccine.
Adult↗
The role of prostaglandin E2 in immune suppression following injury.
It has been thought for some time that prostaglandin E2 (PGE2) released from activated monocytes/macrophages may contribute to the suppression of immunity seen after burns and major injury because PGE2 inhibits the activation of T lymphocytes. To clarify this issue, we studied 15 patients with total body surface area burns of 20% to 90% (mean, 48%). Peripheral blood mononuclear cells (PBMC) were obtained from these patients one to two times each week for 1 month after burn and were stimulated with the T-cell mitogen phytohemagglutinin (PHA). On 14 occasions the PBMCs from eight patients were significantly suppressed (30% or more) in their response to PHA (suppressed [sup] burn) as compared with PBMCs from normal controls. In 38 instances PBMCs from 12 patients were not significantly suppressed in PHA (nonsuppressed [nonsup] burn). Sup burn PBMCs and control PBMCs were cultured with or without the addition of the cyclooxygenase (CO) inhibitor indomethacin (Indo, 1 microgram/mL) and studied for PHA response and the production of the stimulatory cytokine interleukin-2 (IL-2). Indo partially restored the PHA response of sup burn PBMCs to normal. Sup burn PBMCs also were deficient in production of IL-2. Indo increased IL-2 production by sup burn PBMCs significantly more (160% +/- 20%, p less than 0.005) than control (57% +/- 5%) and nonsup PBMCs (67% +/- 8%). Next inhibition of the PHA response of PBMCs from 12 burn patients and 17 controls was studied by exogenous PGE2. At all time periods after burn injury, patients' PBMCs were significantly more sensitive to inhibition by PGE2 (50% inhibition at 10(-8) mol/L [molar] PGE2) than PBMCs from normal controls (50% inhibition at 10(-6) mol/L PGE2) with maximum sensitivity occurring 8 to 14 days after injury. Peripheral blood mononuclear cells from patients with more than 40% burns were significantly (p less than 0.05) more sensitive to PGE2 than those from patients with lesser burns. Interleukin-2 was added to cultures of sup burn PBMC, nonsup burn PBMC, and controls containing 10(-7) mol/L PGE2. Interleukin-2 totally reversed PGE2 inhibition of the PHA response in PBMC from both controls and burn patients. Because endotoxin leak from the gut has been implicated as a trigger for a number of the metabolic and immunologic abnormalities following injury, the authors looked for the effect of a bolus infusion of Escherichia coli endotoxin (Endo, 4 ng/kg) in seven normal healthy volunteers on the response of PBMC to PHA and on the production of PGE2 and IL-2.(ABSTRACT TRUNCATED AT 400 WORDS)
Adolescent↗
Evidence for a novel gene expression program in peripheral blood mononuclear cells from Mycobacterium avium subsp. paratuberculosis-infected cattle.
A bovine-specific cDNA microarray system was used to compare gene expression profiles of peripheral blood mononuclear cells (PBMCs) from control uninfected (n = 4) and Johne's disease-positive (n = 6) Holstein cows. Microarray experiments were designed so that for each animal, a direct comparison was made between PBMCs stimulated in vitro with Mycobacterium avium subsp. paratuberculosis and PBMCs stimulated with phosphate-buffered saline (nil-stimulated PBMCs). As expected, M. avium subsp. paratuberculosis stimulation of infected cow PBMCs enhanced expression of gamma interferon transcripts. In addition, expression of 15 other genes was significantly affected (>1.25-fold change; P < 0.05) by in vitro stimulation with M. avium subsp. paratuberculosis. Similar treatment of control cow PBMCs with M. avium subsp. paratuberculosis resulted in significant changes in expression of 13 genes, only 2 of which were also affected in PBMCs from the infected cow PBMCs. To compare gene expression patterns in the two cow infection groups (infected cows and uninfected cows), a mixed-model analysis was performed with the microarray data. This analysis indicated that there were major differences in the gene expression patterns between cells isolated from the two groups of cows, regardless of in vitro stimulation. A total of 86 genes were significantly differentially expressed (P < 0.01) in M. avium subsp. paratuberculosis-stimulated PBMCs from infected cows compared to expression in similarly treated PBMCs from control cows. Surprisingly, a larger number of genes (110 genes) were also found to be significantly differentially expressed (P < 0.01) in nil-stimulated cells from the two infection groups. The expression patterns of selected genes were substantiated by quantitative real-time reverse transcriptase PCR. Flow cytometric analysis indicated that there were no gross differences in the relative populations of major immune cell types in PBMCs from infected and control cows. Thus, data presented in this report indicate that the gene expression program of PBMCs from M. avium subsp. paratuberculosis-infected cows is inherently different from that of cells from control uninfected cows.
Animals↗
[Effect of glucocorticoid on glucocorticoid-resistant children with primary nephrotic syndrome].
OBJECTIVE: Glucocorticoid (GC) is the first therapeutic choice of primary nephrotic syndrome (PNS). The response to GC treatment is an important indicator for the outcome of PNS children. Children with GC-resistant PNS present with incomplete or no response to GC, and may herald the progression to end-stage renal failure. However, the detailed mechanism of GC-resistance or GC-sensitive effect in these PNS children has not been clearly elucidated. The previous study by the authors indicated that there was increased expression of GR beta in PBMCs in GC-resistant children with PNS, and the over expression of GR beta resulted in GC resistance via influencing the ability of GR alpha nuclear translocation. To elucidate the relationship between GR beta expression in renal and in PBMCs and the effect of glucocorticoid on glucocorticoid-resistance children with PNS, the expression of GR alpha and GR beta in renal tissue and in PBMCs were detected by immunohistochemistry. METHODS: Forty children with PNS were divided into two groups, GC-resistant group(20) and GC-sensitive group(20), the expression of GR alpha and GR beta in renal intrinsic cells and in PBMCs were measured with the immunohistochemistry technique. A semiquantitative score was used to evaluate the injury degree of the glomeruli and tubulointerstitium. RESULTS: Compared with GC-sensitive group, the glomerular pathologic scores (6.91 +/- 1.98) and renal tubular pathologic scores (7.12 +/- 1.62) in GC- resistant group were significantly different (P < 0.01, respectively). GR alpha expressions of renal tissue and PBMCs were higher in the control group (58.3 +/- 2.6, 59.1 +/- 7.2) than those in the GC-sensitive group (40.2 +/- 7.2 and 36.6 +/- 5.1, P < 0.01, respectively) and GC-resistant group (35.0 +/- 8.2 and 36.4 +/- 6.6, P < 0.01, respectively). GR beta expressions of renal tissue and PBMCs were higher in the GC-resistant group (13.8 +/- 3.0 and 12.1 +/- 4.1) and in the GC-sensitive group (6.5 +/- 1.9 and 5.9 +/- 1.0) than that in control group (2.3 +/- 0.4 and 3.2 +/- 1.1, P < 0.01, respectively). GR beta expressions in renal tissue and PBMCs were higher in the GC-resistant group than that in the GC-sensitive group (P < 0.01). Compared with control group, GR beta expressions in PBMCs and in renal tissue were lower than those in mild renal lesion group (5.4 +/- 2.8, 6.46 +/- 2.50), midmedium renal lesion group (8.7 +/- 2.4 and 11.4 +/- 3.7) and (17.1 +/- 0.4 and 18.7 +/- 0.7) in severe renal lesion group (F = 5.8, 15.6, P < 0.01, respectively). GR beta expression of PBMCs had a positive correlation with GR beta expression of renal intrinsic cells (r = 0.651, P < 0.01). GR beta expressions by PBMCs and renal intrinsic cells were positively correlated with renal pathologic scores (r = 0.579 and 0.623, P < 0.01, respectively). CONCLUSION: GC-resistant children with PNS were related to the increased GR beta expression in PBMCs and renal intrinsic cells. There was no correlation between the GR alpha expressions in PBMCs and in renal intrinsic cells. Increased GR beta expression might decrease the effect of GC via inhibiting the activity of GR alpha.
Adolescent↗
Cytomegalovirus cultured from different major leukocyte subpopulations: association with clinical features in CMV immunoglobulin G-positive renal allograft recipients.
Cytomegalovirus (CMV) cultured from peripheral blood mononuclear cells (PBMCs) was shown to be associated more closely with clinical manifestations than infectious CMV in polymorphonuclear leukocytes (PMNLs) of renal allograft recipients with secondary CMV infection. Shell vial culture was carried out with ficoll-purified PBMCs and PMNLs of 71 CMV IgG-positive patients after kidney transplantation. Thirty-six patients experienced active CMV infections. Of these, 17 developed clinical symptoms. The diagnostic value of PMNLs and PBMCs viremia was determined in comparison to pp65 antigenemia, leukoDNAemia, plasma DNAemia, and detection of cytomegalic endothelial cells. In both PMNLs and PBMCs (with or without detectable endothelial cells), frequencies and levels of viremia were significantly higher among symptomatic patients. Regarding the occurrence of clinical CMV manifestations, the sensitivity of culture from PMNLs and from PBMCs fractions was 100%. Viremia in PBMCs, however, was far more specific (94%) than in PMNLs (74%). Cutoff values established previously for pp65 antigenemia and leukoDNAemia, standard markers in the laboratory, had similar specificity (96% each) to PBMCs viremia, but were less sensitive (88% each). Plasma DNA-emia was both less sensitive (82%) and less specific (69%) than PBMCs viremia. Detection of endothelemia showed maximal specificity (100%), but inferior sensitivity (47%). All patients had PBMCs viremia before the onset of symptoms. In conclusion, infectious CMV present in PBMCs may prove to be a determinant of clinical CMV manifestations in seropositive immunocompromised individuals. Factors involved in PBMCs tropism may help to understand the pathogenetic mechanisms of CMV dissemination in this group of patients.
Cells, Cultured↗
Detection of hepatitis C virus RNA in peripheral blood mononuclear cells and in saliva.
The nested polymerase chain reaction (PCR) technique was applied to investigate hepatitis C virus (HCV) RNA in the peripheral blood mononuclear cells (PBMCs), saliva, and serum of patients with chronic type C hepatitis. The specificity of the amplified products was analyzed and confirmed by agarose gel electrophoresis, Southern blot hybridization, and restriction endonuclease pattern analysis. HCV RNA was detectable in the PBMCs of 24% (12/50) of the patients. The HCV RNA detected in PBMCs was not due to the contamination from plasma, since no viral sequences could be detected in the third washing of PBMCs. Of the 12 patients with HCV RNA in PBMCs, five were negative for HCV RNA sequences in the serum. Thus the presence of HCV RNA in PBMCs was not strictly correlated to the results for sera. Among 25 patients with HCV RNA in their saliva, 18 were negative for PBMCs. Among 25 patients without HCV RNA in their saliva, five had HCV RNA in PBMCs. In conclusion, PBMCs are an extrahepatic target for chronic HCV infection. However, we do not suggest that PBMCs act as a vehicle for carrying HCV to saliva, since the presence of HCV RNA in PBMCs and in saliva was not closely correlated.
Base Sequence↗
Interleukin 12-augmented T cell proliferation of peripheral blood mononuclear cells from HIV-seropositive individuals is associated with interleukin 12 receptor beta 2 upregulation.
Interleukin 12 (IL-12) production is believed to be impaired in individuals with HIV infection and this impairment manifests early in disease, when the CD4(+) cell counts are within normal values. The reduced antigen-specific and mitogen-stimulated T cell-proliferative responses that occur in HIV infection can be corrected by the addition of recombinant human interleukin 12 (rhIL-12). As the IL-12 receptor (IL-12R) is central to the IL-12 signaling pathway, we examined whether the augmentation of antigen-specific proliferation of HIV(+) peripheral blood mononuclear cells (PBMCs) related to altered IL-12R expression. rhIL-12 augmented antigen-specific proliferation of HIV(+) PBMCs but not of HIV(-) PBMCs. Examination of resting PBMCs from HIV(+) and HIV(-) donors showed that neither of these populations expressed IL-12R beta 1 or IL-12R beta 2 chains on their cell surface as detected by flow cytometry. However, examination of mRNA showed that both IL-12R beta 1 and IL-12R beta 2 mRNAs were markedly reduced in HIV(+) PBMCs when compared with HIV(-) PBMCs. After mitogen activation there was an increase in IL-12R beta 1 expression on the cell surface of HIV(+) and HIV(-) PBMCs and this level was not altered by coculture with rhIL-12 or interferon gamma (IFN-gamma). However, coculture of phytohemagglutinin (PHA)-activated HIV(+) or HIV(-) PBMCs with rhIL-12 (but not IFN-gamma) increased IL-12R beta 2 expression on the cell surface of both populations. Examination at the message level showed a correction of IL-12R beta 1 to normal levels with activation that was further enhanced by rhIL-12 coculture for both the HIV(+) and HIV(-) PBMCs. However, although the level of IL-12R beta 2 for the HIV(+) PBMCs was normalized by PHA, rhIL-12 caused a further augmentation. This information provides a strong link between IL-12R upregulation, and the significant improvement in antigen-specific HIV-proliferative responses seen with the addition of rhIL-12. It also reveals that the dysfunction in IL-12R expression seen in cells from HIV(+) patients occurs at the transcriptional level. In addition, we provide further evidence that IL-12R beta 1 and IL-12R beta 2 regulation in human PBMCs is independent of IFN-gamma.
HIV Infections↗
Induction of TNF-alpha in human peripheral blood mononuclear cells by the mannoprotein of Cryptococcus neoformans involves human mannose binding protein.
We have shown previously that specific receptors on PBMCs and a serum factor other than Ab and complement are involved in the TNF-alpha response to cryptococcal mannoprotein (MP2). To characterize the mechanism of MP2 recognition by PBMCs, 10(6) PBMCs were incubated with 25 microg of FITC-labeled MP2 in 10% normal human serum (1 h). The cells were analyzed by flow cytometry. FITC-MP2 binding was CaCl2 and temperature dependent and was enhanced by prestimulating PBMCs with unlabeled MP2. Binding to PBMCs was specific, since unlabeled MP and mannan produced dose-dependent inhibition. Beta-Glucan laminarin produced background inhibition. mAbs against CD14, CD11b, and CD18 did not prevent FITC-MP2 binding to PBMCs, implying that these receptors are not involved in MP2 recognition by PBMCs. mAb against CD14 blocked (>90%) MP2-induced TNF-alpha release by PBMCs, while mAbs against CD11b/CD18 caused no inhibition. Removal of human mannose binding protein (hMBP) by preincubation of serum with a specific mAb abrogated TNF-alpha induction by MP2 and strongly inhibited its binding to PBMCs. Recombinant hMBP enhanced TNF-alpha induction by MP2 as well as binding of FITC-MP2 to PBMCs. In addition, incubation of serum with MP2-coated beads and analysis by SDS-PAGE resulted in the detection of a protein of approximately 33/34 kDa that could be partially removed by preincubating the serum with hMBP mAb. We conclude that hMBP is involved in the binding of MP2 to PBMCs and the release of TNF-alpha.
Antigens, CD↗
Phosphorylation of 3'-azidothymidine in maternal and fetal peripheral blood mononuclear cells during gestation and at term.
The present study compared the phosphorylation rate of 3'-azidothymidine (AZT) in isolated maternal and fetal peripheral blood mononuclear cells (PBMCs) with that in amniocytes obtained during gestation and at term. Maternal PBMCs were isolated from venous blood samples obtained from HIV-seronegative pregnant women during delivery. Immediately after delivery, cord blood specimens were collected, and fetal PBMCs were isolated. In a separate set of experiments, maternal and fetal PBMCs and amniocytes were obtained at 17-21 weeks of gestation. The fresh isolated PBMCs and amniocytes were maintained in RPMI 1640 medium until incubation with 10 microM tritiated AZT (10 microCi/mL). Thereafter, methanolic cell extracts were prepared for determination of AZT phosphates by high-performance liquid chromatography. Fetal PBMCs can efficiently convert AZT to its antivirally active metabolite. There were no significant differences after 6 or 12 hours of incubation with AZT between AZT phosphate levels in maternal and fetal PBMCs isolated at term or at 17-21 weeks of gestation: AZT monophosphate was found to be the major metabolite (about 95%). AZT phosphate levels in the amniocytes were up to sevenfold higher than those in the maternal or fetal PBMCs. These results show that during pregnancy and at term, fetal PBMCs-like maternal PBMCs-are able to take up AZT and to efficiently generate the active metabolite AZT triphosphate. These results are of major significance both in enabling efficient treatment of the fetuses of HIV-infected women and in the prediction and understanding of the efficacy and toxicity of AZT in pregnant women and their fetuses.
Amnion↗
Gene expression profiling of peripheral blood mononuclear cells from cattle infected with Mycobacterium paratuberculosis.
A bovine-specific cDNA microarray system containing 721 unique leukocyte expressed sequence tags (ESTs) and amplicons representing known genes was used to compare gene expression profiles of peripheral blood mononuclear cells (PBMCs) from clinical and subclinical Johne's disease-positive Holstein cows (n = 2 per group). Stimulation of PBMCs from clinically infected cows with Mycobacterium paratuberculosis tended to decrease expression of 83 genes (fold change, >1.5). Of these 83 genes, 16 displayed significant down regulation across both clinical cows (P < 0.1), including genes encoding microspherule protein 1, fibroblast growth factor, and the Lyn B protein kinase. Only eight genes from PBMCs of clinically infected cows exhibited a modest up regulation following stimulation with M. paratuberculosis, including those encoding bovine CD40L, gamma interferon, interleukin-10 (IL-10), and tissue inhibitor of matrix metalloproteinases (TIMP) 4. In contrast, stimulation of PBMCs from subclinically infected cows with M. paratuberculosis tended to up regulate expression of 71 genes representing 68 unique transcripts. Of these, 11 genes showed significant up regulation (fold change, >1.5; P < 0.1) across both animals, including those encoding bovine CD40L, several matrix metalloproteinases, and SPARC (secreted protein, acidic and rich in cystine). Repression of gene expression was also observed in PBMCs from the subclinical cows, with 16 genes being significantly down regulated (fold change, >1.5; P < 0.1) across both animals, including those encoding the bovine orthologs of cytochrome oxidase subunit III, IL-1 receptor type I, and fibrinogen-like 2 protein. Only one clone, representing an unknown bovine EST, was similarly down regulated in PBMCs from both the clinical and subclinical cows. Thus, the most prominent change induced by exposure of PBMCs from clinical cows to M. paratuberculosis in vitro tended to be repression of gene expression, while changes in similarly treated PBMCs from subclinical cows was balanced between gene activation and repression. Comparison of gene expression profiles between PBMCs from clinical and uninfected (control) cows stimulated with the general mitogen concanavalin A were highly similar (overall r = 0.84), suggesting that M. paratuberculosis-induced gene repression in clinically infected cow PBMCs was not due to a general failure of the immune response in these animals.
Animals↗
Specificity of T cells in synovial fluid: high frequencies of CD8(+) T cells that are specific for certain viral epitopes.
INTRODUCTION: Epstein-Barr virus (EBV) is transmitted orally, replicates in the oropharynx and establishes life-long latency in human B lymphocytes. T-cell responses to latent and lytic/replicative cycle proteins are readily detectable in peripheral blood from healthy EBV-seropositive individuals. EBV has also been detected within synovial tissue, and T-cell responses to EBV lytic proteins have been reported in synovial fluid from a patient with rheumatoid arthritis (RA). This raises the question regarding whether T cells specific for certain viruses might be present at high frequencies within synovial fluid and whether such T cells might be activated or able to secrete cytokines. If so, they might play a 'bystander' role in the pathogenesis of inflammatory joint disease. OBJECTIVES: To quantify and characterize T cells that are specific for epitopes from EBV, cytomegalovirus (CMV) and influenza in peripheral blood and synovial fluid from patients with arthritis. METHODS: Peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) were obtained from patients with inflammatory arthritis (including those with RA, osteoarthritis, psoriatic arthritis and reactive arthritis). Samples from human leucocyte antigen (HLA)-A2-positive donors were stained with fluorescent-labelled tetramers of HLA-A2 complexed with the GLCTLVAML peptide epitope from the EBV lytic cycle protein BMLF1, the GILGFVFTL peptide epitope from the influenza A matrix protein, or the NLVPMVATV epitope from the CMV pp65 protein. Samples from HLA-B8-positive donors were stained with fluorescent-labelled tetramers of HLA-B8 complexed with the RAKFKQLL peptide epitope from the EBV lytic protein BZLF1 or the FLRGRAYGL peptide epitope from the EBV latent protein EBNA3A. All samples were costained with an antibody specific for CD8. CD4+ T cells were not analyzed. Selected samples were costained with antibodies specific for cell-surface glycoproteins, in order to determine the phenotype of the T cells within the joint and the periphery. Functional assays to detect release of IFN- or tumour necrosis factor (TNF)- were also performed on some samples. RESULTS: The first group of 15 patients included 10 patients with RA, one patient with reactive arthritis, one patient with psoriatic arthritis and three patients with osteoarthritis. Of these, 11 were HLA-A2 positive and five were HLA-B8 positive. We used HLA-peptide tetrameric complexes to analyze the frequency of EBV-specific T cells in PBMCs and SFMCs (Figs 1 and 2). Clear enrichment of CD8+ T cells specific for epitopes from the EBV lytic cycle proteins was seen within synovial fluid from almost all donors studied, including patients with psoriatic arthritis and osteoarthritis and those with RA. In donor RhA6, 9.5% of CD8+ SFMCs were specific for the HLA-A2 restricted GLCTLVAML epitope, compared with 0.5% of CD8+ PBMCs. Likewise in a donor with osteoarthritis (NR4), 15.5% of CD8+ SFMCs were specific for the HLA-B8-restricted RAKFKQLL epitope, compared with 0.4% of CD8+ PBMCs. In contrast, we did not find enrichment of T cells specific for the HLA-B8-restricted FLRGRAYGL epitope (from the latent protein EBNA3A) within SFMCs compared with PBMCs in any donors. In selected individuals we performed ELISpot assays to detect IFN- secreted by SFMCs and PBMCs after a short incubation in vitro with peptide epitopes from EBV lytic proteins. These assays confirmed enrichment of T cells specific for epitopes from EBV lytic proteins within synovial fluid and showed that subpopulations of these cells were able to secrete proinflammatory cytokines after short-term stimulation. We used a HLA-A2/GILGFVFTL tetramer to stain PBMCs and SFMCs from six HLA-A2-positive patients. The proportion of T cells specific for this influenza epitope was low (<0.2%) in all donors studied, and we did not find any enrichment within SFMCs. We had access to SFMCs only from a second group of four HLA-A2-positive patients with RA. A tetramer of HLA-A2 complexed to the NLVPMVATV epitope from the CMV pp65 protein reacted with subpopulations of CD8+ SFMCs in all four donors, with frequencies of 0.2, 0.5, 2.3 and 13.9%. SFMCs from all four donors secreted TNF after short-term incubation with COS cells transfected with HLA-A2 and pp65 complementary DNA. We analyzed the phenotype of virus-specific cells within PBMCs and SFMCs in three donors. The SFMC virus-specific T cells were more highly activated than those in PBMCs, as evidenced by expression of high levels of CD69 and HLA-DR. A greater proportion of SFMCs were CD38+, CD62L low, CD45RO bright, CD45RA dim, CD57+ and CD28- when compared with PBMCs. DISCUSSION: This work shows that T cells specific for certain epitopes from viral proteins are present at very high frequencies (up to 15.5% of CD8+ T cells) within SFMCs taken from patients with inflammatory joint disease. This enrichment does not reflect a generalized enrichment for the 'memory pool' of T cells; we did not find enrichment of T cells specific for the GILGFVFTL epitope from influenza A or for the FLRGRAYGL epitope from the EBV latent protein EBNA3A, whereas we found clear enrichment of T cells specific for the GLCTLVAML epitope from the EBV lytic protein BMLF1 and for the RAKFKQLL epitope from the EBV lytic protein BZLF1. The enrichment might reflect preferential recruitment of subpopulations of virus-specific T cells, perhaps based on expression of selectins, chemokine receptors or integrins. Alternatively, T cells specific for certain viral epitopes may be stimulated to proliferate within the joint, by viral antigens themselves or by cross-reactive self-antigens. Finally, it is theoretically possible that subpopulations of T cells within the joint are preferentially protected from apoptotic cell death. Whatever the explanation, the virus-specific T cells are present at high frequency, are activated and are able to secrete proinflammatory cytokines. They could potentially interact with synoviocytes and contribute to the maintenance of inflammation within joints in many different forms of inflammatory arthritis.
Antigens, Surface↗
HCV replication in PBMC and its influence on interferon therapy.
AIM: To study hepatic virus C (HCV) RNA and HCV protein expression in peripheral blood mononuclear cells (PBMCs) of patients with HCV infection, and explore the relationship between the HCV RNA in the PBMCs and response to interferon (IFN) therapy. METHODS: Type-specific primers were designed and RT-nested PCR was used to detect the plus- and minus- strands of HCV RNA in PBMCs of 54 patients with HCV infection; Indirect immunofluorescence assay was applied to identify HCVNS5 protein expression in PBMCs; 6 month-, 3 MU-IFN regiment was administrated to observe the responses to IFN in 35 chronic hepatitis C patients with different HCV RNA status in PBMCs. RESULTS: HCV plus strand RNA was found in 10 of 19 (52.6 %) acute hepatitis C patients and 22 of 35 (62.9 %) chronic hepatitis C patients. HCV minus strand RNA was detected in 14 of 35 (40.0 %) chronic hepatitis C patients, but only one patient (5.3 %) with acute HCV infection was found to be minus HCV RNA positive. Though no HCV NS5 protein expression was found in the examined 10 cases of acute HCV infection, it was positive in 17 of 20 (85.0 %) chronic hepatitis C patients by indirect immunofluorescence assay. There are significant differences of positive rate of the minus-strand and HCVNS5 protein between acute and chronic hepatitis C groups (u=2.07, P<0.05 and u=4.43, P<0.01 respectively). The patients with minus-strand HCV RNA showed a significantly lower 6-month sustained response (SR-6) to IFN compared to those without minus-strand HCVRNA in PBMCs (biologically 14.3 % vs 42.8 %, chi(2)=4.12, P<0.05 and virologically 7.1 % vs 23.9 %, chi(2)=4.24, P<0.05). CONCLUSION: HCV is capable of infecting and replicating in PBMCs, and HCVNS5 protein was expressed in PBMCs. The patients with minus strand HCV RNA in PBMCs showed a significantly lower 6-month sustained response to IFN, suggesting that minus-strand HCV RNA in PBMCs may be one of the factors influencing response to IFN therapy.
Antiviral Agents↗