High Levels Of HLA-DR Research Articles

Defective Severe Acute Respiratory Syndrome Coronavirus 2 Immune Responses in an Immunocompromised Individual With Prolonged Viral Replication.

We describe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)–specific immune responses in a patient with lymphoma and recent programmed death 1 (PD-1) inhibitor therapy with late onset of severe coronavirus disease 2019 disease and prolonged SARS-CoV-2 replication, in comparison to age-matched and immunocompromised controls. High levels of HLA-DR+/CD38+ activation, interleukin 6, and interleukin 18 in the absence of B cells and PD-1 expression was observed. SARS-CoV-2–specific antibody responses were absent and SARS-CoV-2–specific T cells were minimally detected. This case highlights challenges in managing immunocompromised hosts who may fail to mount effective virus-specific immune responses.

Prognostic Value of Macrophage Phenotypes in Resectable Non–Small Cell Lung Cancer Assessed by Multiplex Immunohistochemistry

Macrophages are important inflammatory cells that regulate innate and adaptive immunity in cancer. Tumor-associated macrophages (TAMs) are thought to differentiate into two main phenotypes: proinflammatory M1 and protumorigenic M2. Currently, the prognostic impact of TAMs and their M1 and M2 phenotypes is unclear in non–small cell cancer (NSCLC). The present study was set up to evaluate an approach for identifying common M1 and M2 macrophage markers and explore their clinical significance in NSCLC. Using multiplex chromogenic immunohistochemistry, tissue microarrays of 553 primary tumors and 143 paired metastatic lymph nodes of NSCLC specimens were stained to detect various putative macrophage phenotypes: M1 (HLA-DR/CD68), M2 (CD163/CD68), M2 (CD204/CD68), and pan-macrophage (CD68/CK). Correlation analyses were performed to examine the relationship between TAMs and adaptive/innate immune infiltrates. HLA-DR+/CD68+M1 TAM level significantly decreased from pathological stage I to III. In a compartment-specific correlation analysis, moderate to strong correlations were observed between both TAM subsets (M1 and M2) with CD3-, CD8-, CD4-, and CD45RO-positive immune cells. Survival analyses, in both stromal and intratumoral compartments, revealed that high levels of HLA-DR+/CD68+M1 (stroma, hazard ratio [HR] = 0.73, P = .03; intratumor, HR = 0.7, P = .04), CD204+M2 (stroma, HR = 0.7, P = .02; intratumor, HR = 0.6, P = .004), and CD68 (stroma, HR = 0.69, P = .02; intratumor, HR = 0.73, P = .04) infiltration were independently associated with improved NSCLC-specific survival. In lymph nodes, the intratumoral level of HLA-DR+/CD68+M1 was an independent positive prognostic indicator (Cox model, HR = 0.38, P = .001). In conclusion, high levels of M1, CD204+M2, and CD68 macrophages are independent prognosticators of prolonged survival in NSCLC.

P054 CD103+SIRPα+ DC are specifically decreased in the inflamed colon from patients with ulcerative colitis but not with Crohn’s disease

Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is a chronic inflammation of the human gastrointestinal (GI) tract. Intestinal dendritic cells (DC) are essential to maintain the balance between immunity against pathogens and tolerance towards nutrients and commensals. However, there is not much information about DC composition in the human GI tract both in health and IBD. Human GI biopsies were obtained from healthy controls and IBD patients (including UC and CD; both active and quiescent). Tissue was disaggregated and lamina propria mononuclear cells (LPMC) characterised by flow cytometry. Human intestinal DC were identified within singlet viable leucocytes as CD14-CD64-HLA-DR+CD11c+. Type 1 DC were defined as CD103+SIRPα- while type 2 DC were identified as SIRPα+ and further divided into subsets based on the expression of CD103. The proportion of total DC displayed a gradient throughout the healthy human gut as it was higher in the colon (either distal or proximal) compared with the ileum. DC proportion was further decreased in the duodenum. Type 1 (minority) and type 2 (majority) conventional DC did not change their proportion throughout the healthy gut. However, CD103+SIRPα+ DC were the main subset in the duodenum as opposed to CD103-SIRPα+ DC which were predominant in the colon and the ileum. Compared with their CD103-SIRPα+ type 2 counterparts, CD103+SIRPα+ had higher levels of HLA-DR, CD40, CD86, CCR7, CD137L, ICOSL and PD-L1. CD103+SIRPα+ were also more phagocytic and had lower expression of blood-related markers like CLA and CCR2, suggesting that they are derived from CD103-SIRPα+ DC following mucosal conditioning. Indeed, CD103+SIRPα+ numbers were increased following LPMC culture, although this process was reverted in the presence of pro-inflammatory LPS. CD103+SIRPα+ DC displayed an enhanced production of IL-10, both in resting conditions and in the presence of LPS. In IBD, type 2 DC constitutively displayed lower expression of SIRPα irrespectively of IBD-type (CD or UC) or condition (active or quiescent). Nevertheless, the inflamed colon from UC patients, but not from CD, specifically displayed lower numbers of tolerogenic CD103+SIRPα+ DC. These results were in agreement with the colonic cytokine milieu, which was much more pro-inflammatory in UC patients compared with CD. Tolerogenic PD-L1 expression and IL-10 production was associated with CD103+SIRPα+ DC, confirming therefore their tolerogenic phenotype. Human colonic DC from IBD patients constitutively display lower levels of SIRPα. The specific reduction of CD103+SIRPα+ DC in the inflamed mucosa from UC, but not CD, suggests the presence of different pathogenic mechanisms occurring in IBD.

CD32-Expressing CD4 T Cells Are Phenotypically Diverse and Can Contain Proviral HIV DNA.

Efforts to both characterize and eradicate the HIV reservoir have been limited by the rarity of latently infected cells and the absence of a specific denoting biomarker. CD32a (FcγRIIa) has been proposed to be a marker for an enriched CD4 T cell HIV reservoir, but this finding remains controversial. Here, we explore the expression of CD32 on CD3+CD4+ cells in participants from two primary HIV infection studies and identify at least three distinct phenotypes (CD32low, CD32+CD14+, and CD32high). Of note, CD4 negative enrichment kits remove the majority of CD4+CD32+ T cells, potentially skewing subsequent analyses if used. CD32high CD4 T cells had higher levels of HLA-DR and HIV co-receptor expression than other subsets, compatible with their being more susceptible to infection. Surprisingly, they also expressed high levels of CD20, TCRαβ, IgD, and IgM (but not IgG), markers for both T cells and naïve B cells. Compared with other populations, CD32low cells had a more differentiated memory phenotype and high levels of immune checkpoint receptors, programmed death receptor-1 (PD-1), Tim-3, and TIGIT. Within all three CD3+CD4+CD32+ phenotypes, cells could be identified in infected participants, which contained HIV DNA. CD32 expression on CD4 T cells did not correlate with HIV DNA or cell-associated HIV RNA (both surrogate measures of overall reservoir size) or predict time to rebound viremia following treatment interruption, suggesting that it is not a dominant biomarker for HIV persistence. Our data suggest that while CD32+ T cells can be infected with HIV, CD32 is not a specific marker of the reservoir although it might identify a population of HIV enriched cells in certain situations.

Interrelation of tumor infiltrating lymphocyte subpopulations with clinical and pathomorphological features of a breast cancer

Levels of intratumoral lymphocytes have direct interrelations with clinical, morphological and biological characteristics of tumor. Rates of CD4+lymphocytes rise in a process of increase of tumor size. At the same time, content of intratumoral CD4+CD25+ lymphocytes is maximal at small size tumors. In the absence of metastases of a breast cancer in the regional lymph nodes are noted a higher content of activated (HLA-DR+) intratumoral T-lymphocytes (CD3, CD4, CD8), which is represented in a higher levels of HLA-DR+CD45+ lymphocytes in patients with a lack of metastasis in comparison with patients, who has metastasis. In case of II and III grade of breast cancer malignancy the percent of intratumoral lymphocytes is higher, in comparison to I grade malignancy. The rate of intratumoral lymphocytes as well as activated T-cells (CD3) and T-helpers (CD4) is higher in stage I of breast cancer, then in II–III stages. The number of intratumoral CD3+ T-lymphocytes and CD8+ cells is higher in tumors with low level of Ki-67+ proliferated cells. Authentically higher content of activated T-cells and activated CD4+ lymphocytes is noted in HER-2 / neu-negative cases. Higher content of CD4+CD3+ T-lymphocytes was noted in 2–3 scores of HER-2 / neu than negative HER-2 / neu status. At an infiltrative ductal cancer authentically higher levels of infiltration of a tumor are revealed by the lymphocytes, activated T-cells and activated T-killers CD3+CD8+. Tumor infiltration levels in luminal A cancer are 5 times higher, then in luminal B (10,5 and 2,2 % correspondingly). At the same time, luminal B subtype is characterized by higher tumor infiltration of T-lymphocytes (81 and 70 %).

Different maturation cocktails provide dendritic cells with different chemoattractive properties.

BackgroundDendritic cells (DC) are currently implemented as immunotherapeutic strategy for the treatment of tumor patients based on their central role in the immune system. Despite good results were obtained in vitro and in animal models, their clinical use has provided limited success suggesting the requirement to optimise the protocol for their production.MethodsA cDNA array was performed on FastDC obtained from the differentiation of human peripheral blood monocytes stimulated with the clinical gold standard or with two alternative maturation cocktails combining interferon (IFN)γ and ligands for different toll like receptors (TLR).ResultsA stronger modulation of the DC transcriptome with respect to immature DC was found in alternatively stimulated DC when compared to DC stimulated with the clinical gold standard. A major class of molecules differentially expressed using distinct DC stimulation protocols were chemokines. Validation of their differential expression pattern at the mRNA and protein level confirmed the secretion of inflammatory chemokines by the alternative DC. Functional analyses of the chemotactic properties of DC “wash out” supernatants highlighted the ability of alternative, but not of gold standard DC to efficiently recruit immune cells with a prevalence of monocytes. Effector cells belonging to the innate as well as adaptive immunity were also attracted and the interaction with alternative DC resulted in enhanced secretion of IFNγ and induction of cytotoxic activity. Using leukocytes from cancer patients, it was demonstrated that the monocyte-attracting activity targeted cells with an inflammatory phenotype characterised by high levels of HLA-DR expression.ConclusionsDespite other classes of immune modulatory genes differently expressed in the alternative DC require to be investigated and characterised regarding their functional consequences, the reduced maturation state and chemoattractive properties of the gold standard versus alternative DC clearly promote the necessity to change the clinically used maturation cocktail of DC in order to improve the outcome of patients treated with DC-based vaccines.

Decreased Tim-3 expression is associated with functional abnormalities of monocytes in decompensated cirrhosis without overt bacterial infection

Patients with advanced cirrhosis usually exhibit altered monocyte function. However, the molecular mechanisms underlying the functional changes of monocytes are poorly understood. We investigated the role of T-cell immunoglobulin domain and mucin domain-containing molecule-3 (Tim-3) in regulating monocyte function in 94 patients with decompensated liver cirrhosis (DC-LC) (decompensation was defined by ascites, hepatic encephalopathy or upper gastrointestinal bleeding), 58 with compensated liver cirrhosis (C-LC) and 52 healthy controls (HC) by characterizing the frequency of Tim-3(+) monocytes, their phagocytosis capacity, HLA-DR expression, cytokine secretion and MAP kinase activation induced by lipopolysaccharide (LPS). Tim-3 expression on CD14(+) monocytes in DC-LC group were significantly lower than that in C-LC and HC and were associated with increased levels of plasma endotoxin, enhanced cytokine production, decreased phagocytic capacity, and reduced HLA-DR expression. Tim-3 expression on monocytes and monocyte function did not differ between C-LC and HC group. Tim-3(+)CD14(+) cells had more potent phagocytic capacity, higher levels of HLA-DR, CD86, CD80, CD163, and CD206 expression, but lower levels of CD1a and CD83, related to that of Tim-3(-)CD14(+) monocytes. In addition, Tim-3(+)CD14(+) cells produced less TNF-α but higher levels of IL-10 in response to LPS. Treatment with anti-Tim-3 antibody significantly reduced phagocytic capacity, but enhanced LPS-stimulated TNF-α, IL-6, and IL-10 secretion. Furthermore, blocking Tim-3 signaling increased p38 MAP kinase phosphorylation in monocytes upon LPS stimulation. Downregulation of Tim-3 expression was associated with endotoxemia and functional alterations of monocytes in patients with decompensated cirrhosis.

Subclinical Atherosclerosis and Markers of Immune Activation in HIV-Infected Children and Adolescents

HIV-infected adults display increased cardiovascular disease, probably driven by inflammation and immune activation. These relationships have not been addressed in vertically HIV-infected children and adolescents, a population at very high risk for long-term non-AIDS complications. Carotid intima media thickness (IMT) was measured in a cohort of HIV-infected children and adolescents and healthy controls. C-reactive protein and markers of immune activation (CD38⁺HLA-DR⁺) and immune senescence (CD28⁻CD57⁺) were determined. One hundred fifty HIV-infected patients and 150 controls were included, 64.8% female. IMT was thicker in HIV-infected patients (0.434 mm ± 0.025 vs. 0.424 mm ± 0.018, P < 0.001). After adjustment by age, sex, body mass index, and smoking status, HIV infection was independently associated with thicker IMT (odds ratio, 2.28; 95% confidence interval: 1.25 to 4.13; P = 0.007). Among HIV-related variables, a low CD4 nadir was related to an increased IMT. Although HIV-infected subjects presented higher frequencies of activated CD4⁺ and CD8⁺ T cells (P = 0.002 and P = 0.087, respectively), no relation was found between IMT and inflammation, immune activation, or senescence. Structural changes of the vasculature present early in vertically HIV-infected subjects as well as immune activation and senescence. These patients should be carefully monitored for the prompt detection and early treatment of cardiovascular disease.

DC-LAMP + Dendritic Cells Are Recruited to Gastric Lymphoid Follicles in Helicobacter pylori-Infected Individuals

Infection with Helicobacter pylori is associated with development of ulcer disease and gastrointestinal adenocarcinoma. The infection leads to a large infiltration of immune cells and the formation of organized lymphoid follicles in the human gastric mucosa. Still, the immune system fails to eradicate the bacteria, and the substantial regulatory T cell (Treg) response elicited is probably a major factor permitting bacterial persistence. Dendritic cells (DCs) are professional antigen-presenting cells that can activate naive T cells, and maturation of DCs is crucial for the initiation of primary immune responses. The aim of this study was to investigate the presence and localization of mature human DCs in H. pylori-infected gastric mucosa. Gastric antral biopsy specimens were collected from patients with H. pylori-associated gastritis and healthy volunteers, and antrum tissue was collected from patients undergoing gastric resection. Immunohistochemistry and flow cytometry showed that DCs expressing the maturation marker dendritic cell lysosome-associated membrane glycoprotein (DC-LAMP; CD208) are enriched in the H. pylori-infected gastric mucosa and that these DCs are specifically localized within or close to lymphoid follicles. Gastric DC-LAMP-positive (DC-LAMP(+)) DCs express CD11c and high levels of HLA-DR but little CD80, CD83, and CD86. Furthermore, immunofluorescence analyses demonstrated that DC-LAMP(+) DCs are in the same location as FoxP3-positive putative Tregs in the follicles. In conclusion, we show that DC-LAMP(+) DCs with low costimulatory capacity accumulate in the lymphoid follicles in human H. pylori-infected gastric tissue, and our results suggest that Treg-DC interactions may promote chronic infection by rendering gastric DCs tolerogenic.

Pathogenesis of the syndrome of hemolysis, elevated liver enzymes, and low platelet count (HELLP): a review

HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome is serious for the mother and the offspring. HELLP occurs in 0.2-0.8% of pregnancies and in 70-80% of cases it coexists with preeclampsia (PE). This review concerns the pathogenetic mechanisms of HELLP syndrome with an emphasis on differences between HELLP and early onset PE. The syndromes show a familial tendency. A previous HELLP pregnancy is associated with an increased risk of HELLP as well as PE in subsequent pregnancies, indicating related etiologies. No single world-wide genetic cause for excessive risk of HELLP or PE has been identified. Combinations of multiple gene variants, each with a moderate risk, with contributing effects of maternal and environmental factors, are probable etiological mechanisms. Immunological maladaptation is the most probable trigger of the insult to the invading trophoblast. This insult occurs early in the first trimester, as indicated by marker molecules in maternal blood. The levels of fetal messenger RNAs in maternal blood at gestational weeks 15-20 are significantly more abnormal in HELLP than in PE, suggesting that the insult is more extensive in HELLP. High levels of HLA-DR in maternal blood in women with HELLP may suggest a similarity to the rejection reaction. In third trimester placentas, gene derangement is more extensive in HELLP. Anti-angiogenic factors released into maternal blood induce the maternal syndromes. Maternal blood levels of anti-angiogenic sFlt1 are similar, but endoglin and Fas Ligand levels are possibly higher in HELLP than in PE. These factors trigger the vascular endothelium, resulting in an enhanced inflammatory response which is stronger in HELLP. Activated coagulation and complement, with high levels of activated leucocytes, inflammatory cytokines, TNF-α, and active von Willebrand factor, induce thrombotic microangiopathy with platelet-fibrin thrombi in microvessels. The angiopathy results in consumption of circulating platelets, causes hemolysis in affected microvessels and reduces portal blood flow in the liver. Placental Fas Ligand damages hepatocytes, resulting in periportal necrosis. In about one half of women with HELLP, activation of coagulation factors and platelets precipitates disseminated intravascular coagulation, which in a minority becomes uncompensated and contributes to life-threatening multiorgan failure.

Ex vivo recovery and activation of dysfunctional, anergic, monocyte-derived dendritic cells from patients with operable breast cancer: critical role of IFN-alpha

BackgroundDendritic cells (DCs) play a crucial role in initiating effective cell-mediated immune responses, but are dysfunctional and anergic in breast cancer. Reversal of this dysfunction and establishment of optimal DC function is a key prerequisite for the induction of effective anti-cancer immune responses.ResultsPeripheral blood DCs (PBDCs) and lymph node DCs (LNDCs) generated in vitro from adherent cultures of peripheral blood monocytes (PBMs) and lymph node monocytes (LNMs), respectively, using the 4 cytokine conditioned medium (CCM) (GM-CSF+IL-4+TNF-α+IFN-α) or 3 CCM (GM-CSF+IL-4+TNF-α) demonstrated a significantly higher degree of recovery and functional capacity in a mixed lymphocyte DC reaction (MLDCR, p < 0.001), expressed significantly higher levels of HLA-DR, CD86, compared with 2 CCM (GM-CSF+IL-4) or medium alone generated DCs from PBMs and LNMs (p < 0.001). The PBDCs generated with 3 CCM or 4 CCM showed a significantly (p < 0.001) enhanced macropinocytotic capability (dextran particles) and induced increased production and secretion of interleukin-12p40 (IL-12p40) in vitro (p < 0.001), compared with PBDCs generated from monocytes using 2 CCM or medium alone. Lipopolysaccharide (LPS) stimulation of PBDCs generated with 4 CCM demonstrated enhanced secretion of IL-6 but not IL-12p70, compared with control DCs unstimulated with LPS (p < 0.001).ConclusionDysfunctional and anergic PBDCs and LNDCs from patients with operable breast cancer can be optimally reversed by ex vivo culturing of precursor adherent monocytes using a 4 CCM containing IFN-α. Maximal immunophenotypic recovery and functional reactivation of DCs is seen in the presence of IFN-α. However, 4 CCM containing IFN-α generated-PBDCs, do not produce and secrete IL-12p70 in vitro.

Immunological Profile of Heterosexual Highly HIV‐Exposed Uninfected Individuals: Predominant Role of CD4 and CD8 T‐Cell Activation

Altered T cell subset distribution patterns in uninfected individual highly exposed to human immunodeficiency virus (HIV) have been explained either as a consequence of viral exposure or as a surrogate marker of low susceptibility to infection. Multiple genetic and immunological parameters were studied prospectively in 21 HIV-serodiscordant heterosexual couples. We found changes of both CD4(+) and CD8(+) T cells in highly HIV-exposed, uninfected individuals, with a lower level of naive and CD28(+) T cells and higher levels of HLA-DR(+) T cells and CD4(+) T cells expressing CCR5 and memory CD4(+) T cells than in control subjects. The changes in memory and activated T cells observed in highly HIV-exposed, uninfected partners were directly correlated with plasma viral load (PVL) of the HIV-1-infected partners, whereas changes in naive and CD4(+) CD28(+) T cells observed in highly HIV-exposed uninfected partners were inversely correlated with PVL of the HIV-1-infected partners. We were only able to detect HIV-1-specific T-cell responses in a few highly HIV-exposed uninfected partners. These data suggest that the peripheral immune cells of highly exposed, uninfected individuals responded according to the level of HIV exposure from the partner, even though evidence of specific HIV stimulation is rarely seen.

Efficient in vitro expression of the human reverse transcriptase (hTERT) but impaired maturation in dendritic cells of lung cancer patients

13518 An innovative treatment strategy for patients with lung cancer is the targeting of tumor associated antigens with cellular effector cells. The telomerase catalytic subunit (hTERT) is an attractive target for cytotoxic T cells that is highly expressed in both NSCLC and SCLC cells. The aim of the study was the expression of hTERT in dendritic cells (DC) that are the most powerful antigen presenting cells for the induction of cellular immune responses. We used electrotransfection of DC with hTERT mRNA that enables an HLA independent whole antigen approach potentially targeting a wide range of hTERT epitopes. Immature DC were prepared from peripheral blood monocytes in serum-free growth medium, GM-CSF and IL-4. Subsequently the DC were electroporated with mRNA and matured in a cytokine cocktail consisting of IL-1 beta, IL-6, TNF-alpha and PGE2. Verification of hTERT mRNA transfection efficiency was performed by analyzing the induction of telomerase activity with the TRAP assay, the efficiency of GFP electrotransfection was determined by FACS. To optimize mRNA electrotransfection conditions the DCs of 3 healthy individuals were transfected with green fluorescent protein (GFP) mRNA. The percentage of electrotransfected DC was in between 18–89% (mean 46%). Subsequently we electrotransfected DCs in 3 lung cancer patients (1 SCLC, 2 NSCLC). In 1 patient GFP mRNA transfection resulted in 62% GFP positive DC. In the 2 other patients the telomerase activity in the DC 24 hrs after hTERT electrotransfection was equivalent to HL60 cells that biologically express high levels of hTERT. Importantly the DC of one patient did not mature after electrotransfection and incubation in the maturation cocktail. The same was true in another patient, in whom an electrotransfection was not done. In both patients the DC were expressing high levels of HLA-DR and no lineage markers, but CD83 as an indicator of maturation was found in only 1% and 9% respectively. Also the costimulatory molecules CD80 and CD86 were expressed at low levels only. These data show that strong hTERT expression can be achieved in DCs of lung cancer patients using mRNA electrotransfection but demontrate the need for other more potent maturation stimuli. No significant financial relationships to disclose.

A New Subset of Human Naive CD8+ T Cells Defined by Low Expression of IL-7Rα

Concomitant with an increased number of memory-type cells, the amount of naive T cells steadily declines with age. Although the regulatory mechanisms behind this conversion are not fully understood, the suggestion is that both alterations in thymic output and homeostatic signals mold the naive T cell pool. In this study, we identify a new subset of circulating CD27(high)CD45RA(high) CD8+ T cells characterized by low IL-7Ralpha message and protein expression. Analysis of TCR repertoire and TCR excision circle content together with ex vivo recovery of IL-7Ralpha expression indicated that these cells should be placed into the naive T cell pool. Compared with conventional IL-7Ralpha(high) naive T cells, this subset displayed significantly lower levels of CD28 and higher levels of HLA-DR. Proliferative responses to anti-CD3/CD28 mAbs were indistinguishable from conventional naive T cells, but the responsiveness to IL-7 was limited. Strikingly, IL-7Ralpha(low) naive T cells were particularly increased in circumstances of naive CD8+ T cells shortage, as in the elderly, in patients early after hemopoietic stem cell transplantation, and in HIV-infected individuals. As common gamma chain cytokines induce rapid down-regulation of IL-7Ralpha, we propose that this new subset of naive T cells may encompass cells that have recently received homeostatic signals.

CpG-Independent Synergistic Induction of β-Chemokines and a Dendritic Cell Phenotype by Orthophosphorothioate Oligodeoxynucleotides and Granulocyte-Macrophage Colony-Stimulating Factor in Elutriated Human Primary Monocytes

Chemokines attract leukocytes bearing the relevant chemokine receptors and regulate innate immune responses. CpG oligodeoxynucleotides (ODN) and GM-CSF are potent vaccine adjuvants and in combination induce enhanced Th1 responses by mechanisms yet to be determined. We have examined combinations of CpG- or non-CpG-ODN and GM-CSF for effects on the production of chemokines and the differentiation of monocytes to dendritic cells. High levels of the Th1-attracting, HIV-1-inhibitory chemokines, CCL3/MIP-1alpha and CCL4/MIP-1beta, were induced in human primary monocytes when CpG- or non-CpG-ODN was combined with GM-CSF, but not with IL-4 or IFN-gamma. The synergistic induction of beta-chemokines by non-CpG-ODN was phosphorothioate (PS) chemistry dependent and inhibited by blocking endosome maturation/acidification and ERK1/2 activation. Chemokine and TLR9 mRNAs were induced by PS-ODN. Cells treated with non-CpG PS-ODN and GM-CSF expressed dendritic cell marker CD83 and high levels of HLA-DR and costimulatory molecules, and were CD14(-) or CD14(dim), consistent with monocyte differentiation into a dendritic cell phenotype. The induction of CD83 and beta-chemokines was tyrosine phosphorylation dependent. Secreted CCL3 and CCL4 were detected as a heterodimer. Our results indicate the CpG-independent synergy between PS-ODN and GM-CSF mediated through chemokine and dendritic cell induction. In addition, our observations suggest that PS-ODN plus GM-CSF may be useful as potent ex vivo dendritic cell differentiation/maturation agents for dendritic cell therapy and as vaccine adjuvants for tumor and infectious microorganisms, including HIV-1.

Feasibility to generate monocyte-derived dendritic cell from coculture with melanoma tumor cells in the presence of granulocyte/macrophage colony-stimulating factor (GM-CSF) and interleukin-4.

We investigated how melanoma cells and membrane-bound granulocyte/macrophage colony stimulating factor (mbGM-CSF) melanoma cell lines affect the differentiation of dendritic cells (DC) from CD14+ monocytes. The malignant melanoma cell lines (Conley and Jorp) and mbGM-CSF-positive cell lines (Conley B-F8 and Jorp C-E6) were cultured and cell-free supernatants were collected from each cell line cultures to assess the GM-CSF level. Adherent monocytes were cocultured for 6-7 days with irradiated mbGM-CSF and wild type melanoma cells (50 Gy) at each 1:1 and 0.1:1 ratio in six-well culture plates in ex vivo culture medium containing interleukin (IL)-4. Immunophenotyping was performed by triple color immunofluorescence staining with flow cytometry analysis. GM-CSF was detected at low levels in the culture supernatants of Conley B-F8 (0.48 ng/10(6) cells/24 hr), whereas there was no detectable GM-CSF in that of Conley melanoma cell line. Monocytes cultured with GM-CSF/IL-4 generated the expression of high levels of HLA DR, CD1a and CD86, while the expression of CD14 and CD83 were in low amounts. However, the addition of GM-CSF to these cultures resulted in an increased expression of these markers and decreased that of CD14. Monocytes cocultured with Jorp C-E6 illustrated similar expression pattern of CD1a, HLA DR and CD14 in the presence or absence of GM-CSF as Conley B-F8 melanoma cell line. Monocytes cocultured with Conley B-F8 melanoma cells at 1:1 and 0.1:1 ratio showed no significant difference in expression of CD1a, CD14 and CD83 between the two ratios. Our results illustrate the feasibility to generate monocyte-derived DC from coculture with melanoma tumor cells in the presence of GM-CSF and IL-4. However, mbGM-CSF tumor cells did not significantly enhance the DC differentiation through juxtacrine stimulation unless soluble GM-CSF was added in the culture media.

Effect of vulvar cancer cell coculture on the development of dendritic cell using peripheral blood

Objective: The effect of melanoma cell coculture on generating human dendritic cells(DC) from CD14+ monocytes has not been extensively studies yet. We investigated how melanoma cells and membrane-bound granulocyte/macrophage colony stimulating factor (mbGM-CSF) melanoma cell lines affect the differentiation of DC obtained by in vitro coculture of plastic-adherent blood monocytes with the presence or absence of GM-CSF and interleukin(IL)-4. Method: The malignant melanoma cell lines(Conley and Jorp) were used in this study. Conley B-F8 and Jorp C-E6 are mbGM-CSF-positive cells derived from Conley and Jorp respectively. Each cell-free supernatants were collected and used to assess the level of GM-CSF using ELISA. Peripheral blood was collected from healthy donors. Adherent monocytes were cocultured for 6-7 days with irradiated mbGM-CSF and wild type melanoma cells(50 Gy) at each 1:1 and 0.1:1 ratio in 6-well culture plates in X-vivo culture medium containing IL-4. In control experiments, GM-CSF was added at the time of culture initiation. Immunophenotyping was performed by triple color immunofluorescence staining with flow cytometry analysis. Results: In this study, GM-CSF was detected at low levels in the culture supernatants of Conley B-F8 (0.48 ng/106 cells/24h), whereas there was no detectable GM-CSF in that of Conley melanoma cell line. ELISA demonstrated that Jorp C-E6 cells produced 18 ng/106 cells/24h, whereas Jorp wild type produced 3.6 pg/106 cells/24h. Monocytes cultured with GM-CSF/IL-4 generated the expression of high levels of HLA DR, CD1a and CD86, while the expression of CD14 and CD83 were in low amounts. After culture in medium containing IL-4 alone, monocytes cocultured with Conley B-F8 showed low levels of CD1a and CD86 and relatively low value of HLA DR. However, the addition of GM-CSF to these cultures resulted in an increased expression of these markers and decreased that of CD14. Monocytes cocultured with Jorp C-E6 illustrated similar expression pattern of CD1a, HLA DR and CD14 in the presence or absence of GM-CSF as Conley B-F8 melanoma cell line. Monocytes cocultured with Conley B-F8 melanoma cells at 1:1 and 0.1:1 ratio showed no significant difference in expression of CD1a, CD14 and CD83 between two ratio. Conclusion: Our results illustrate the feasibility to generate monocyte-derived DC from coculture with melanoma tumor cells in the presence of GM-CSF and IL-4. However, mbGM-CSF tumor cells did not significantly enhance the DC differentiation through juxtacrine stimulation unless soluble GM-CSF was added in the culture media.

Dendritic cells derived from peripheral monocytes express endothelial markers and in the presence of angiogenic growth factors differentiate into endothelial-like cells

CD14-positive monocytes obtained from human peripheral blood were cultured with GM-CSF and IL-4. During the early culture phase immature dendritic cells (DCs) developed which not only expressed CD1a, HLA-DR and CD86, but also expressed the endothelial cell markers von Willebrand factor (vWF), VE-cadherin and VEGF receptors Flt-1 and Flt-4. Further maturation of DCs was achieved by prolonged cultivation with TNFalpha. These cells showed typical DC morphology and like professional antigen-presenting cells (APCs) expressed CD83 and high levels of HLA-DR and CD86. However, if immature DCs were grown with VEGF, bFGF and IGF-1 on fibronectin/vitronectin-coated culture dishes, a marked change in morphology into caudated or oval cells occurred. In the presence of these angiogenic growth factors the cultured cells developed into endothelial-like cells (ELCs), characterized by increased expression of vWF, KDR and Flt-4 and a disappearance of CD1a and CD83. Addition of IL-4 and Oncostatin M also increased VE-cadherin expression, and the loosely adherent cells formed clusters, cobblestones and network-like structures. vWF- expressing ELCs mainly originated from CD1a-positive cells, and VEGF was responsible for the decrease in the expression of the DC markers CD1a and CD83. In mixed leukocyte cultures, mature DCs were more potent APCs than ELCs. Moreover, Ac-LDL uptake, and the formation of tubular structures on a plasma matrix was restricted to ELCs. These results suggest that in the presence of specific cytokines immature DCs have the potential to differentiate along different lineages, i.e. into a cell type resembling ELCs.

Dendritic cells in chronic myelomonocytic leukaemia.

Blood dendritic cells (DC) differentiate in vitro via two separate pathways: either directly from blood DC precursors (DCp) or from CD14+ monocytes. In chronic myelomonocytic leukaemia (CMML) abnormal bone marrow precursors contribute to blood monocyte development but DC development has not been studied previously. Monocytes comprised 60% of blood MNC in 15 CMML patients studied, compared with 20% in 16 age-matched controls. The increase in blood monocytes was accompanied by a reciprocal decrease in mean blood DC percentage (from 0.42% of MNC in normal individuals to 0.16% of MNC in CMML patients). Absolute blood DC numbers showed a minimal (non-significant) reduction from 9.8 x 10(6)/l in normal individuals to 7.5 x 10(6)/l in CMML patients. The CD14(low) WCD16+ monocyte subpopulation was not found in CMML patients. After culture in GM-CSF/IL-4, CMML CD14+ monocytes acquired the phenotype of immature monocyte derived DC (Mo-DC) with similar yields to normal blood Mo-DC generation. Addition of TNF-alpha or LPS induced both normal and CMML Mo-DC to express prominent dendritic processes, the CMRF44+ and CD83+ antigens and high levels of HLA-DR, CD80 and CD86. Treatment either with TNF-alpha or LPS increased the allostimulatory activity of normal Mo-DC, but had little effect on the allostimulatory activity of CMML Mo-DC, perhaps reflecting the underlying neoplastic changes in monocyte precursors. We conclude that the blood DC numbers are relatively unaffected in CMML, suggesting discrete regulation of monocyte and DC production.

Neutrophils Activated by Granulocyte-Macrophage Colony-Stimulating Factor Express Receptors for Interleukin-3 Which Mediate Class II Expression

Freshly isolated peripheral blood neutrophils, unlike monocytes and eosinophils, do not bind interleukin-3 (IL-3) or respond to IL-3). We show that neutrophils cultured for 24 hours in granulocyte-macrophage colony-stimulating factor (GM-CSF) express mRNA for the IL-3 receptor (R) alpha subunit, as shown by RNase protection assays, and IL-3R alpha chain protein, as shown by cytometric analysis using two different specific monoclonal antibodies. This effect was selective for GM-CSF, because granulocyte colony-stimulating factor, tumor necrosis factor-alpha, interferon-gamma, and IL-1 failed to induce the IL-3 receptor. Saturation binding curves with 125I-IL-3 and Scatchard transformation showed the presence of about 100 high-affinity and 4,000 low-affinity receptors. Because neutrophils have been shown to express human leukocyte antigen (HLA)-DR in response to GM-CSF, we examined the possibility that IL-3 could augment HLA-DR expression on GM-CSF-treated cells. We found that neutrophils incubated with 30 ng/mL IL-3 as well as 0.1 ng/mL GM-CSF expressed a mean of 2.1-fold higher levels of HLA-DR than with GM-CSF alone (P < .005), confirming the signaling competence of the newly expressed IL-3R. This increase was seen even at maximal concentrations of GM-CSF and IL-3 can have an additive effect on mature human cells. The augmentation of HLA-DR by IL-3 was specific because it could be inhibited by a blocking anti-IL-3R antibody. Expression of class II molecules by neutrophils under these conditions may have significance for antigen presentation. These results provide further evidence for the role of GM-CSF as an amplification factor in inflammation by inducing neutrophil responsiveness to IL-3 produced by T cells or mast cells.