Increased Expression Of HLA-DR Research Articles

The expression of HLA-DR by monocytes from black and from white donors: different requirements for protein synthesis

Epidemiologic data indicates that blacks may be more susceptible than whites to infection by Mycobacterium tuberculosis. Resistance to the in vivo growth of Mycobacteria in mice correlates with the persistence of MHC class II expression by peritoneal macrophages. The expression of HLA-DR by human monocytes from different groups of individuals also differs. The increase in the expression of HLA-DR by monocytes that occurs upon in vitro culture was prevented by the protein synthesis inhibitor cycloheximide (CHX) in a majority of black donors. In contrast, the increase in HLA-DR expression by monocytes from the majority of white donors was unaffected.

Influence of Vaccination and Surgery on HLA-DR Expression in Patients with Upper Aerodigestive Tract Cancer

Major surgery is associated with an increased risk of post-operative immunosuppression and infections. We investigated the influence of influenza vaccination on cell-mediated immune responses in cancer patients undergoing either surgical or conservative therapy. Forty patients with an upper aerodigestive tract tumour were allocated to either a surgical or non-surgical treatment course. Patients within each group were randomized to the vaccination or non-vaccination group. Vaccination was performed twice before surgery or conservative treatment. Human leucocyte antigen receptor (HLA-DR) expression on monocytes was analysed by flow cytometry. In the surgical patients, HLA-DR expression on day 1 after surgery decreased in both the vaccinated and non-vaccinated groups. Vaccinated non-surgical patients showed significantly increased HLA-DR expression levels compared with the non-vaccinated patients. This pilot study demonstrated that vaccination increased monocyte HLA-DR expression in conservatively-treated cancer patients whereas surgery abrogated this response. Vaccination before surgery, therefore, might not help to maintain immune reactivity after surgery.

Preserved Central Memory and Activated Effector Memory CD4+T-Cell Subsets in Human Immunodeficiency Virus Controllers: an ANRS EP36 Study

Human immunodeficiency virus (HIV) controllers are rare individuals who spontaneously control HIV type 1 replication for 10 years or more in the absence of antiretroviral treatment. In the present study, HIV controllers (n = 11) maintained potent HIV-specific CD4 responses in spite of very low antigenic loads. Their CD4+ central memory T (T(CM)) cells were characterized by near-normal numbers and preserved interleukin-2 (IL-2) secretion in response to HIV antigens and uniformly high expression of the survival receptor IL-7 receptor alpha (IL-7Ralpha). Controllers expressed CCR7 at higher levels than uninfected controls, suggesting differences in T(CM)-cell homing patterns. CD4+ effector memory T (T(EM))-cell responses were polyfunctional in HIV controllers, while IL-2 secretion was lost in viremic patients. Cytokine production was three times higher in controllers than in treated patients with undetectable viral loads, suggesting an intrinsically more efficient response in the former group. The total CD4+ T(EM)-cell pool underwent immune activation in controllers, as indicated by increased HLA-DR expression, decreased IL-7Ralpha expression, a bias towards gamma interferon production upon polyclonal stimulation, and increased macrophage inflammatory protein 1beta secretion associated with chronic CCR5 down-regulation. Thus, HIV controllers showed a preserved CD4+ T(CM)-cell compartment and signs of potent functional activation in the CD4+ T(EM)-cell compartment. While controllers did not show the generalized immune activation pattern associated with disease progression, they had signs of immune activation restricted to the effector compartment. These findings suggest the induction of an efficient, nondetrimental type of immune activation in patients who spontaneously control HIV.

Tumour-derived microvesicles modulate biological activity of human monocytes

Tumour cells are shedding membrane fragments (tumour-derived microvesicles, TMV) that may interact with cells of immune system. Our previous observations indicated that TMV carry several surface determinants and mRNA of tumour cells and transfer some of them to monocytes. This study determined the effect of TMV on biological activity of human monocytes as the precursors of tumour infiltrating macrophages (TIM). It was found that TMV activated monocytes as shown by an increased HLA-DR expression, induced production of ROI (reactive oxygen intermediates) and of tumour necrosis factor (TNF), interleukin (IL)-10, IL-12p40 accumulation of mRNA and their secretion. Induction of TNF synthesis was CD44 dependent as blocking of CD44 on monocytes abolished its secretion. TMV-treated monocytes showed an increased antitumour activity as judged by enhanced cytotoxicity/cytostasis against tumour cells in vitro. Taken together, these results indicate that TMV significantly modulate biological activity of monocytes and thus mimic the effect of tumour cells on them. This may suggest that tumour cells interact with TIM not only via direct contact, soluble factors, but also TMV.

Granulocyte-Macrophage Colony-Stimulating Factor (GM‐CSF) Restores Decreased Monocyte HLA‐DR Expression after Cardiopulmonary Bypass

Cardiopulmonary bypass (CPB) is associated with a disturbed immune response, e.g., impaired HLA-DR expression on monocytes and the release of pro- and anti-inflammatory cytokines. Cytokine release plays a role in the pathogenesis of postoperative systemic inflammatory response syndrome (SIRS) and immune system deterioration, e.g., impaired monocyte and polymorphonuclear neutrophil (PMN) function, factors that ultimately lead to an increased susceptibility to infections. To gain a further understanding, we investigated HLA-DR expression on monocytes and on B- and T-lymphocytes. In addition, we investigated the IN VITRO effect of the immunostimulating hematopoietic growth factor granulocyte-macrophage colony-stimulating factor (GM-CSF) on HLA-DR expression of these cell types. Neither HLA-DR expression on B- and T-lymphocytes nor the effects of GM-CSF in cardiac surgical patients have been studied before. In 16 patients undergoing elective cardiac surgery with CPB, counts of circulating leukocyte subsets as well as HLA-DR expression on monocytes, B- and T-lymphocytes were measured by flow cytometry before, immediately after CPB, and on the 2nd and 10th postoperative days. Treatment with GM-CSF was performed IN VITRO in whole blood cultures with 100 ng/ml recombinant human GM-CSF for 20 h. Monocyte HLA-DR expression was attenuated immediately after CPB (125 +/- 4 mean channel fluorescence [MCF] vs. 143 +/- 2 MCF preoperatively, mean +/- SEM, P < 0.001). HLA-DR expression further decreased on the 2nd day after CPB and did not normalize until the 10th day after the operation. In contrast, HLA-DR expression on T-cells was unchanged, whereas HLA-DR expression on B-cells did not decrease before the 2nd day after CPB (152 +/- 3 MCF vs. 170 +/- 2 MCF preoperatively, P < 0.001). IN VITRO GM-CSF treatment increased HLA-DR expression on monocytes prepared after CPB to a degree comparable to preoperative values. HLA-DR expression on B-lymphocytes could not be restored by GM-CSF. Immune system suppression after cardiac surgery is reflected in prolonged diminished HLA-DR expression on monocytes and B-lymphocytes. Suppression is not irreversible but can - at least IN VITRO - be overridden by the immunostimulating compound GM-CSF.

Negative regulation of MHC class II gene expression by CXCR4

CXCR4 is overexpressed in 23 types of cancers of both hematopoietic and nonhematopoietic origin. Based on the known role of CXCR4 and its ligand CXCL12 in homing of hematopoietic cells, CXCR4 is likely to play a role in metastasis. We have initiated a study aimed at dissecting additional functions of CXCR4 in cancer cells, particularly in relation to the immune system. RNA from CXCR4+ and CXCR4- subpopulations of MDA-MB-231 breast cancer cells was subjected to microarray analysis. Cell surface expression of CXCR4 and MHC class II proteins were determined by flow cytometry. Real-time PCR was used for measuring mRNA levels of MHC class II and CIITA, the master regulator of MHC class II gene expression. 1988 genes were differentially expressed (p < 0.001) between CXCR4+ and CXCR4- cells. The expression of class II genes HLA-DPalpha1, HLA-DQbeta1, HLA-DRalpha, HLA-DRbeta1, HLA-DRbeta3, and CD74 was lower by 2.6-fold to eightfold in CXCR4+ cells compared to CXCR4- cells. Basal and IFN-gamma-inducible HLA-DR mRNA and protein levels were lower in CXCR4+ cells than in CXCR4- cells. HLA-DR mRNA expression in both cell types was reduced by CXCL12; the ability of CXCL12 to reduce HLA-DR was lower in cells expressing short interfering RNA against CXCR4. PKA inhibitor H89 and the SRC kinase inhibitor PP2 increased HLA-DR expression in CXCR4+ cells. The basal but not IFN-gamma-inducible expression of CIITA was 2.5-fold higher in CXCR4- cells compared to CXCR4+ cells. CD34+/CD38- hematopoietic cells from the human bone marrow contain a distinct CXCR4+/HLA-DR- subpopulation of cells. CXCR4 may influence the immune system under physiologic and pathologic conditions through negative regulation of MHC class II expression, possibly through PKA and SRC kinase.

Hyporesponsiveness of T cell subsets after cardiac surgery: a product of altered cell function or merely a result of absolute cell count changes in peripheral blood?

The activity of the specific immune system and especially the function of T helper (TH) cells are reduced after cardiac surgery. This decrease is followed by an increase in TH2 cell activity and a delayed recovery of TH1 cell function (TH1/TH2 shift). Neither the underlying cause nor the relationship between the absolute numbers of T lymphocyte subpopulations, the state of activation of these cells and cytokine synthesis in cell culture has been clarified. We conducted a prospective study in order to test the hypothesis that the decrease in specific immunity is not caused by dilution effects but by functional alterations in T cell subsets. Blood samples were obtained from 40 patients undergoing elective cardiac surgery with cardiopulmonary bypass (CPB) preoperatively (d0), immediately after surgery (dx), and on the 1st (d1), 3rd (d3) and 5th (d5) postoperative days. The samples were stimulated for 24h with staphylococcal enterotoxin B and lipopolysaccharide. Interferon (IFN)-gamma, interleukin (IL)-2, IL-4, and IL-5 concentrations were measured by flow cytometry using a cytokine bead array kit. We determined white blood cell counts, analysed lymphocyte populations, and assayed human leukocyte antigen (HLA)-DR expression on cluster of differentiation (CD)4+ and CD8+ lymphocytes. Cytokine concentrations were corrected to preoperative absolute numbers of T helper cells. Leukocyte counts were elevated during the entire postoperative course with a maximum on dx. Absolute lymphocyte counts and especially the T cell subpopulations significantly increased immediately after surgery, then decreased to a minimum on d1 and increased again until they returned to preoperative levels on d3. The release of IFN-gamma, IL-2 and IL-4 was significantly reduced from dx to d5 with a minimum on d1. IL-5 was significantly reduced on dx and d1. When the concentrations were corrected to preoperative TH lymphocyte levels, IL-2 and IL-5 synthesis was significantly reduced only on dx and IL-4 release only on dx and d1. By contrast, IFN-gamma synthesis decreased postoperatively and remained suppressed until d5 with a minimum on d1. Only on d1 did an increase in HLA-DR expression give evidence of a change in the state of TH cell activation. The number of immune cells of the specific and the non-specific immune system is not reduced in the immediate postoperative period. Haemodilution thus has no detectable effect on immune function at this time point. Beginning on d1, the function of specific immune cells, especially TH lymphocytes, is severely suppressed. This functional alteration appears not to be preceded by T cell activation during CPB. Although TH cell activity begins to increase on d1, cytokine synthesis is reduced. When cytokine synthesis is corrected to the absolute number of TH cells in culture, there is strong evidence for an increase in TH2 cell activity. On the whole, these results corroborate the hypothesis of a TH1/TH2 shift that is primarily caused by an alteration of TH1 function. Neither haemodilution nor a preceding activation plays a major role.

Monocyte Anergy Is Present in Patients With Severe Acute Pancreatitis and Is Significantly Alleviated by Granulocyte-Macrophage Colony-stimulating Factor and Interferon-?? In Vitro

Severe acute pancreatitis (AP) is frequently associated with immune suppression, which increases the risk of infections, organ failure, and death. Our aims were to measure monocyte function (ie, HLA-DR expression and tumor necrosis factor-alpha [TNF-alpha] production as markers of immune suppression) in patients with severe AP and to determine whether treatment of blood samples with granulocyte-macrophage colony-stimulating factor (GM-CSF) and/or interferon-gamma (IFN-gamma) corrected the functional defects of monocytes in vitro. The study consisted of 28 patients with severe AP who were treated at intensive care unit and in whom the proportion of HLA-DR-positive monocytes in the circulation was less than 70%, and 28 matched control subjects who were selected from healthy laboratory personnel. HLA-DR density was determined by whole blood flow cytometry. Monocyte TNF-alpha production in response to bacterial lipopolysaccharides (LPSs) was studied in a whole blood assay. Aliquots of blood were supplemented with IFN-gamma (all 28 patients), GM-CSF (the last 24 patients), or both (the last 12 patients). The median proportion of HLA-DR-positive monocytes was 45% in patients (range, 18%-73%) and was 98% in controls (range, 86%-100%; P < 0.001). TNF-alpha levels in response to LPSs were lower in patients (545 pg/mL; range, 84-1990 pg/mL) than in controls (1415 pg/mL; range, 660-5490 pg/mL; P < 0.001). The proportion of HLA-DR-positive cells correlated positively with TNF-alpha levels (r = 0.56; P < 0.01). Both GM-CSF and IFN-gamma increased HLA-DR expression of monocytes in patients (98%; range, 74%-100% for GM-CSF; 99%; range, 86%-100% for IFN-gamma; both P < 0.001). The combination restored monocyte HLA-DR expression (99%; range, 96%-100%; P = 0.002). Compared with basal levels, GM-CSF increased TNF-alpha production of monocytes both in blood samples from patients (median, 1320 pg/mL; range, 35-8015 pg/mL) and controls (median, 3450 pg/mL; range, 1040-9835 pg/mL; both P < 0.001). IFN-gamma increased TNF-alpha production by monocytes in patients (683 pg/mL; range, 186-2705 pg/mL; P < 0.05) but not in controls (1658 pg/mL; range, 765-4755 pg/mL; P = 0.31). With the combination of GM-CSF and IFN-gamma, the TNF-alpha levels of monocytes in patients (3185 pg/mL; range, 545-8280 pg/mL) and in controls (2800 pg/mL; range, 1080-6860 pg/mL) were comparable. The proportion of HLA-DR-positive monocytes correlates with TNF-alpha production, and they both reflect the degree of immune suppression. The low proportion of HLA-DR-positive monocytes in AP can be reversed in vitro by GM-CSF and/or IFN-gamma. The GM-CSF and IFN-gamma treatments also increase LPS-induced TNF-alpha production. By the combination of GM-CSF and IFN-gamma, but not by either agent alone, LPS-induced TNF-alpha production of monocytes was equally high in patients and in controls.

STATINS MODULATE IFN-GAMMA INDUCED HLA-DR EXPRESSION ON INTESTINAL EPITHELIAL CELLS

Aim: Statins have been shown to attenuate IFN-gamma stimulated HLA-DR expression on various cells types. There are no reports investigating effects of statins on intestinal epithelial cells (IECs). In this study we analyse the influence of statins on induced HLA-DR expression on IECs and evaluate toxic effects on these cells. Methods: HT29 cells were grown unstimulated or stimulated with hrIFN-gamma (50 U/ml) for 72 h. Cells were simultaneously incubated with atorvastatin (0-40 μM) or simvastatin (0-40 μM). Co-incubation with mevalonic acid (100-400 μM) served to identify statin specific effects. Cell surface expression of HLA-DR, cell proliferation rates and viability using propidium iodide staining of unfixed or ethanol fixed cells were assessed by flow cytometry. Results: HLA-DR expression, constitutively absent on HT29 cells, was markedly upregulated by IFN-gamma. Ator- (0.1-10.0 μM) as well as simvastatin (0.1-3.0 μM) reduced IFN-gamma stimulated HLA-DR expression on HT29 cells. The effect was most pronounced at 10.0 μM for atorvastatin and 3.0 μM for simvastatin. Unexpectedly higher concentrations of both statins were less effective in lowering IFN-gamma induced HLA-DR and even further increased the induced HLA-DR expression. Co-incubation with mevalonic acid completely abrogated all statins effects, thus indicating the decrease as well as the exacerbation of HLA-DR to be mediated by the inhibition of HMG-CoA reductase activity. Except of simvastatin used at 40 μM, atorand simvastatin did not affect the proliferation and viability of HT29 cells. Summary: Low concentrations of Atorvastatin and Simvastatin reduce IFN-gamma mediated HLA-DR expression on HT29 cells. Unexpectedly, higher concentrations of these statins not only seemed to be less effective in attenuating HLA-DR stimulation but they even further increased the effects of IFN-gamma. Our results indicate that the effects observed are not related to toxic properties of statins on HT29 cells. Conclusion: The immunmodulatory action of statins on IECs in combination with its influence on other immunocompetent cells may be used as antiinflammatory tool in therapeutic strategies for inflammatory bowel disease in the future. However increased HLA-DR expression on IECs due to high concentrations of statins may be in part responsible for gut associated side effects after statin medication.

Statins modulate IFN-gamma induced HLA-DR expression on intestinal epithelial cells

Aim: Statins have been shown to attenuate IFN-γ stimulated HLA-DR expression on various cells types. There are no reports investigating effects of statins on intestinal epithelial cells (IECs). In this study we analyse the influence of statins on induced HLA-DR expression on IECs and evaluate toxic effects on these cells. Methods: HT29 cells were grown unstimulated or stimulated with hrIFN-γ (50U/ml) for 72h. Cells were simultaneously incubated with atorvastatin (0–40µM) or simvastatin (0–40µM). Co-incubation with mevalonic acid (100–400µM) served to identify statin specific effects. Cell surface expression of HLA-DR, cell proliferation rates and viability using propidium iodide staining of unfixed or ethanol fixed cells were assessed by flow cytometry. Results: HLA-DR expression, constitutively absent on HT29 cells, was markedly upregulated by IFN-γ. Ator- (0.1–10.0µM) as well as simvastatin (0.1–3.0µM) reduced IFN-γ stimulated HLA-DR expression on HT29 cells. The effect was most pronounced at 10.0µM for atorvastatin and 3.0µM for simvastatin. Higher concentrations of both statins were less effective in lowering IFN-γ induced HLA-DR and even further increased the induced HLA-DR expression. Co-incubation with mevalonic acid completely abrogated all statins effects, thus indicating the decrease and exacerbation of HLA-DR to be mediated by the inhibition of HMG-CoA reductase action. Except of simvastatin used at 40µM, ator- and simvastatin did not affect the proliferation and viability of HT29 cells. Summary: Low concentrations of Atorvastatin and Simvastatin reduce IFN-γ mediated HLA-DR expression on HT29 cells. Unexpectedly, higher concentrations of these statins not only seemed to be less effective in attenuating HLA-DR stimulation but they even further increased the effects of IFN-γ. Our results indicate that the effects observed are not related to toxic properties of statins on HT29 cells. Conclusion: The immunmodulatory action of statins on IECs and other immunocompetent cells may be used as antiinflammatory tool in therapeutic strategies for inflammatory bowel diseases. However increased HLA-DR expression on IECs due to high concentrations of statins may be in part responsible for gut associated side effects after statin medication.

Effect of influenza virus vaccine on the expression of human immunodeficiency virus co-receptor CCR5

Administration of influenza vaccine to human immunodeficiency virus (HIV)-infected children can lead to increased viral load. CCR5 and CXCR4 are known to play an important role in HIV cell entry and viral replication. To determine the effects of influenza vaccine on chemokine receptors and on viral load in HIV-infected children. Eight HIV-infected children receiving stable therapy and 11 healthy adults were enrolled. Chemokine expression and immune activation were determined before and 48 hours after influenza vaccination. CCR5 and beta-chemokine gene expression were analyzed using real-time polymerase chain reaction. Viral load was measured at baseline, 48 hours, and 6 to 12 weeks. Forty-eight hours after influenza vaccination, mean CCR5 expression was significantly decreased on the CD3 (21.1% vs 11.3% in HIV-infected children; P = .02; and 18.3% vs 10.7% in controls; P = .008) and CD4 (13.0% vs 3.6% in the HIV group; P = .04; and 13.6% vs 6.5% in controls; P = .02) lymphocytes. This was observed in conjunction with an increase in HLA-DR expression on T lymphocytes in HIV-infected children (P = .046). No significant changes were observed in HIV viral load, CD3 and CD8 lymphocyte counts, expression of interleukin 2 receptor and CXCR4, or gene expression of CCR5 and beta-chemokines 48 hours after vaccination. Influenza virus vaccine markedly decreased chemokine receptor CCR5 expression on CD4 T lymphocytes. However, this immunomodulatory effect does not seem to affect overall viral replication in HIV-infected children who received highly active antiretroviral therapy.

Small interfering RNAs mediate sequence-independent gene suppression and induce immune activation by signaling through toll-like receptor 3.

Small interfering (si) and short hairpin (sh) RNAs induce robust degradation of homologous mRNAs, making them a potent tool to achieve gene silencing in mammalian cells. Silencing by siRNAs is used widely because it is considered highly specific for the targeted gene, although a recent report suggests that siRNA also induce signaling through the type I IFN system. When human embryonic kidney 293 (HEK293) or keratinocyte (HaCaT) cell lines or human primary dendritic cells or macrophages were transfected with siRNA or shRNAs, suppression of nontargeted mRNA expression was detected. Additionally, siRNA and shRNA, independent of their sequences, initiated immune activation, including IFN-alpha and TNF-alpha production and increased HLA-DR expression, in transfected macrophages and dendritic cells. The siRNAs induced low, but significant, levels of IFN-beta in HEK293 and HaCaT cells. Secretion of these cytokines increased tremendously when HEK293 cells overexpressed Toll-like receptor 3 (TLR3), and the increased secretion of IFN-beta was inhibited by coexpression of an inhibitor of TIR domain-containing adapter-inducing IFN-beta, the TLR3 adaptor protein linked to IFN regulatory factor 3 signaling. Although siRNA and shRNA knockdown of genes represents a new and powerful tool, it is not without nonspecific effects, which we demonstrate are mediated in part by signaling through TLR3.

Effect of granulocyte-macrophage colony-stimulating factor on the immune response of circulating monocytes after severe trauma.

Severe injury compromises functions of the antigen-presenting immune cells, resulting in an increased vulnerability toward bacterial sepsis. Support of the immune capabilities contributes a desirable therapeutic option in high-risk patients. Factors possessing immunostimulating properties such as granulocyte-macrophage colony-stimulating factor (GM-CSF) may serve as potential tools to compensate immunosuppression caused by severe trauma. In the present study, therefore, GM-CSF was examined with regard to its capacity to overcome trauma-induced down-regulation of immune functions. Prospective clinical experimental study. University hospital intensive care unit and research facility. Severely injured patients with >25 points on the Injury Severity Score. Blood samples of severely injured patients were incubated in vitro with 10 ng/mL GM-CSF for 6 hrs. Human leukocyte antigen (HLA)-DR expression on monocytes was analyzed by flow cytometry, lipopolysaccharide-induced tumor necrosis factor (TNF)alpha and interleukin-10 production of blood samples was measured by means of enzyme-linked immunoabsorbent assay. Compared with blood specimens of healthy donors, ex vivo endotoxin-induced TNF alpha production and HLA-DR expression on monocytes were significantly reduced in blood of trauma patients. Ex vivo treatment of blood specimens with GM-CSF increased HLA-DR expression and TNF alpha production stimulated by lipopolysaccharides in both healthy volunteers and patients on day 1 after trauma. Blood samples of patients with an uneventful recovery showed nearly normal TNF alpha synthesis and HLA-DR expression after 2-3 wks, whereas TNF alpha production and HLA-DR expression of patients with sepsis and multiple organ failure remained at low levels. In the sepsis/multiple organ failure group, GM-CSF also enhanced HLA-DR expression and TNF alpha production, although the levels of the volunteers' blood were not reached. The presented data show that trauma- and sepsis-induced depression of monocyte functions can be counteracted by GM-CSF in vitro, suggesting that this substance may serve as support of immune functions in severely injured patients.

Tackling Inner-City Asthma Vechicles for Success

Sarcoidosis, a chronic granulomatous disease of unknown etiology, is treated with immune suppressive drugs such as corticosteroids. Sarcoidosis patients have been reported to benefit clinically from treatment with thalidomide. We administered thalidomide for 16 weeks to eight patients with chronic skin sarcoidosis and evaluated the drug's effects before and with treatment. After thalidomide treatment, all skin biopsies showed decreases in granuloma size and reduction in epidermal thickness. We also observed extensive T cell recruitment into the granulomas, the appearance of multinucleated giant cells, and increased numbers of dermal Langerhans cells (CD1a+) and mature dendritic cells (CD83+ or DC-LAMP+). Plasma IL-12 levels increased and remained elevated during the treatment period. We noted increased HLA-DR expression on peripheral blood lymphocytes and a corresponding drop in the naive T cell marker CD45RA. Our data suggest that thalidomide treatment of sarcoidosis results in granuloma differentiation to a Th1-type cellular immune response usually associated with protective immunity to tuberculosis and tuberculoid leprosy.

Cow's milk protein induced changes in the expression of HLA-DR antigens on colonic epithelial cells

Normal colonic epithelial cells do not express HLA-DR antigens unless they become inflamed. It is possible that colonic epithelial cells may function as antigen-presenting cells once HLA-DR is induced by infection or inflammation. The aim of this study was to investigate whether cow's milk protein (CMP) is capable of inducing changes in HLA-DR expression on colonic epithelial cells, providing indirect evidence that CMP may activate cell-mediated immune mechanisms within intestinal mucosa. HLA-DR expression was evaluated by flow cytometry on cultured human colonic epithelial cell line (HT-29) before and after treatment with bacterial lipopolysaccharide (LPS) or recombinant gamma interferon (IFN-gamma). Untreated and LPS- or IFN-gamma-treated HT-29 cells were then cultured in the presence of CMP. The changes in epithelial HLA-DR expression induced by CMP on untreated and LPS- or IFN-gamma-treated HT-29 cells were examined. Untreated HT-29 cells expressed very little HLA-DR molecule. Bacterial LPS or IFN-gamma induced a significant HLA-DR expression on HT-29 cells. When untreated HT-29 cells were cultured in the presence of CMP, there was little induction of HLA-DR expression. Culture of LPS- or IFN-gamma-treated HT-29 cells in the presence of CMP induced a significant increase in HLA-DR expression, which was much greater than on HT-29 cells treated with bacterial LPS or IFN-gamma only. Our results suggest that CMP initiates an immune response in the intestinal mucosa and may be responsible for the activation of cell-mediated immunity after enteric infection or inflammation.

Effect of blood transfusion during radiotherapy on the immune function of patients with cancer of the uterine cervix: role of interleukin-10

Purpose: To analyze prospectively the effects of blood transfusion administered during radiotherapy (RT) on the immune function of patients with locally advanced cervical cancer.Methods and Materials: In a total of 15 patients, 7 transfused and 8 untransfused, lymphocyte populations, including CD3+, CD4+, and CD8+ T-cell subsets, B cells (CD19+), and natural killer (NK) cells (CD56+, CD16+, CD3−) were studied before (i.e., time 0), during (i.e., times 1 and 2), and after (i.e., time 3) therapy. Expression of the early (CD25) and late (HLA-DR) activation markers on CD3+ T cells, the intracellular levels of perforin in CD8+ and CD56+ cells, and interferon (IFN)-γ, interleukin (IL)-2, and IL-4 in CD4+ and CD8+ T cells were also measured. NK cell cytotoxicity against the NK-sensitive target K-562 cells and CD8+ T-cell-directed cytotoxicity against OKT3 hybridoma cells were also assessed. Finally, the plasma levels of the immunoregulatory cytokine IL-10 were analyzed by enzyme-linked immunosorbent assay.Results: The mean absolute number of all lymphocyte subsets compared with pretreatment levels decreased significantly during RT of both transfused and untransfused patients (p >0.001), with no detectable differences between the two groups in terms of total lymphocytes or relative numbers of CD3+ and CD4+ T cells, CD56+ NK cells, or CD19+ B cells. In contrast, concomitant with an inversion of the CD4/CD8 ratio, a significant increase in the number of CD8+ T cells at time 2 and CD3+ T cells, CD8+ T cells, and NK cells at time 3 was found in the transfused patients compared with the untransfused group. The percentages of CD25+/CD3+ T cells and HLA-DR+/CD3+ T cells increased during RT of the untransfused patients, but CD3+ T cells showed decreased CD25 expression and increased HLA-DR expression in the transfused group. An increase of CD8+ IFN-γ+ T cells with a concomitant decrease in CD8+ IL-2+ T cells was found in the transfused vs. untransfused group, and no differences were noted in the percentage of CD4+ IFN-γ+ T cells and CD4+ IL-2+ T cells. The proportion of perforin-positive CD8+ and CD56+ cells was higher in the transfused group than in the untransfused group. However, CD56+ cells and CD8+ T cells from the transfused patients showed markedly diminished cytotoxic function. Finally, IL-10 was detected only in the plasma of the transfused patients.Conclusion: Blood transfusion during primary RT for cervical cancer profoundly alters the magnitude and characteristics of radiation-induced immunosuppression. Elevated serum IL-10 in transfused patients may play a role in the disregulation of lymphocyte function, in particular, the depression of NK- and T-cell cytotoxicity. Investigation of alternatives to blood transfusion during RT that do not diminish host immunity is warranted.

Glutamine-Enriched Enteral Nutrition Increases HLA-DR Expression on Monocytes of Trauma Patients

The aim of this study was to investigate the effect of glutamine-(Gln)-enriched enteral nutrition (EN) on human leukocyte antigen (HLA)-DR and FcgammaR1/CD64 expression on monocytes and plasma glutamine concentrations in multi-trauma patients. HLA-DR expression on monocytes is crucial in the presentation of foreign antigen to the immune system and is severely reduced in trauma patients. In vitro monocyte HLA-DR and FcgammaRI/CD64 expression is dependent on glutamine availability. To study the effect of glutamine supplemented enteral nutrition on HLA-DR and FcgammaRI/CD64 expression on CD14(+) monocytes, 55 multi-trauma patients were studied in a randomized, double-blinded, controlled trial. Trauma patients received either a Gln-enriched EN (glutamine group, n = 28) or an isocaloric, isonitrogenous control EN (control group, n = 27) and were compared with a group of age-matched healthy volunteers (healthy volunteers, n = 53). On d 1, 5, 9 and 14 after trauma, expressions of HLA-DR and FcgammaRI/CD64 were determined on CD14(+) monocytes using FACS analysis. Plasma glutamine levels were measured using HPLC. Plasma glutamine was lower in both trauma patient groups compared with healthy volunteers and from d 3 to d 5; glutamine was higher in the glutamine group than in the control group. On d 1, HLA-DR expression was much lower in both trauma patient groups than in healthy volunteers. HLA-DR expression was greater on d 5, 9 and 14 in the glutamine group than in the control group. FcgammaRI/CD64 expression on monocytes of trauma patients was not different than the expression of healthy volunteers. This study showed that glutamine-enriched enteral nutrition was associated with a higher HLA-DR expression on CD14(+) monocytes of trauma patients. No difference in monocyte FcgammaRI/CD64 expression was detected between patients that received the two enteral diets and between trauma patients and the healthy volunteers. Increased HLA-DR expression may improve cellular immune function and may be involved in the beneficial effect of glutamine on the occurrence of infections in trauma patients.

Increased HLA-DR Expression on Peripheral Blood Monocytes in Subsets of Subjects With Primary HIV Infection Is Associated With Elevated CD4 T-Cell Apoptosis and CD4 T-Cell Depletion

Increased HLA-DR Expression on Peripheral Blood Monocytes in Subsets of Subjects With Primary HIV Infection Is Associated With Elevated CD4 T-Cell Apoptosis and CD4 T-Cell Depletion

Thalidomide Induces Granuloma Differentiation in Sarcoid Skin Lesions Associated with Disease Improvement

Sarcoidosis, a chronic granulomatous disease of unknown etiology, is treated with immune suppressive drugs such as corticosteroids. Sarcoidosis patients have been reported to benefit clinically from treatment with thalidomide. We administered thalidomide for 16 weeks to eight patients with chronic skin sarcoidosis and evaluated the drug's effects before and with treatment. After thalidomide treatment, all skin biopsies showed decreases in granuloma size and reduction in epidermal thickness. We also observed extensive T cell recruitment into the granulomas, the appearance of multinucleated giant cells, and increased numbers of dermal Langerhans cells (CD1a+) and mature dendritic cells (CD83+ or DC-LAMP+). Plasma IL-12 levels increased and remained elevated during the treatment period. We noted increased HLA-DR expression on peripheral blood lymphocytes and a corresponding drop in the naive T cell marker CD45RA. Our data suggest that thalidomide treatment of sarcoidosis results in granuloma differentiation to a Th1-type cellular immune response usually associated with protective immunity to tuberculosis and tuberculoid leprosy.

Increased HLA-DR expression after exposure of human monocytic cells to air particulates.

The expression of HLA-DR on the cell membrane of antigen-presenting cells is of major importance for the induction of an allergic response in the airways. Environmental particulates are thought to play an important role in inducing or enhancing allergic sensitization, possibly by increasing the expression of HLA-DR on the cell membrane of antigen-presenting cells. In addition, these particulates may synergize with common sensitizing agents in inducing or enhancing HLA-DR and thus antigen presentation. In this study, we investigated the potential of three particle types, namely carbon black, diesel exhaust particles and urban air particulates (0.1-1000 ng/cm(2)), to induce the expression of HLA-DR on differentiated THP-1 cells, taken as a model for alveolar macrophages. We also assessed the "adjuvant" potential of the particles on interferon (IFN)-gamma, a known enhancer of HLA-DR. By themselves, the particles (0.1-1000 ng/cm(2)) were not able to induce HLA-DR on the THP-1 cells after an incubation of 48 h. However, even at very low concentrations, carbon black (from 1 ng/cm(2) on) and diesel exhaust particles (from 0.1 ng/cm(2) on), interacted with IFN-gamma (100 U/mL) to enhance HLA-DR expression (up to 2.5-fold increase). This finding may reflect in vitro one of the mechanisms by which pollutant particles exert an "adjuvant" activity and may partially explain how exposure to particles can be related to the enhancement of allergic sensitization.