Reduced expression of oestrogen receptor‐β is associated with tumour invasion and metastasis in oestrogen receptor‐α‐negative human papillary thyroid carcinoma

Oestrogens play an important role in the development and progression of papillary thyroid carcinoma (PTC) through oestrogen receptor (ER)‐α and ‐β, which may exert different or even opposing actions in PTC. The roles of ERβ in ERα‐negative PTC are still not clear. This study investigated the expression dynamics of ERβ1 (wild‐type ERβ) and its clinical significance in female ERα‐negative PTC patients. ERβ1 expression was detected in thyroid tissues of 136 female patients diagnosed with PTC. The relationships between ERβ1 expression and clinicopathological/biological factors were also analysed in female ERα‐negative PTC patients. The total score for ERβ1 was significantly lower in female ERα‐negative PTC patients with LNM or ETE when compared to those without LNM or ETE (Z = ?2.923, P = 0.003 and Z = ?3.441, P = 0.001). Accordingly, the total score for ERβ1 was significantly higher in ERα‐negative PTC patients expressing E‐cadherin compared to patients negative for E‐cadherin expression (Z = ?2.636, P = 0.008). The total score was lower in ERα‐negative PTC patients positive for VEGF expression compared to those negative for VEGF expression (Z = ?1.914, P = 0.056). This preliminary study indicates that reduced expression of ERβ1 in female ERα‐negative PTC patients is associated with greater progression of the disease. This may provide insights into the underlying molecular mechanisms of ERβ1 and could help design targeted approaches for treating or even preventing this disease.     

ERK/p38 MAP‐kinases and PI3K are involved in the differential regulation of B7‐H1 expression in DC subsets

Regulatory molecules of the B7‐H‐family expressed by DC are important for immune homeostasis, but their regulation is largely unknown. When investigating the pathways regulating B7‐H1 expression in monocyte‐derived DC (MoDC), freshly isolated myeloid DC (mDC) and plasmacytoid DC, respectively, we showed that in MoDC and mDC B7‐H1 expression was upregulated by a standard cytokine cocktail, poly I:C or LPS. MoDC utilize ERK and PI3K pathways to upregulate B7‐H1 in response to cytokines, whereas p38 kinase was predominantly utilized in response to poly I:C. In mDC, ERK and p38 pathways are involved in B7‐H1 regulation, and similar to MoDC, mainly p38 signaling was required for poly I:C‐induced expression of B7‐H1. Plasmacytoid DC responded only to CpG with upregulation of B7‐H1 and in addition to p38 also utilized the PI3K and ERK pathways to regulate B7‐H1 expression. As a functional consequence of B7‐H1 expression on DC, we demonstrate downmodulation of IFN‐γ production in T cells. Thus, the differential regulation of B7‐H1 on DC subsets may suppress immune responses variably, depending on the target DC population. Further analysis of the regulatory mechanisms may facilitate the development of new immunosuppressive therapies, utilizing the regulation of B7‐H1 expression on DC.     

Soluble HLA‐I‐mediated secretion of TGF‐β1 by human NK cells and consequent down‐regulation of anti‐tumor cytolytic activity

Soluble HLA class I (sHLA‐I) molecules can regulate survival of NK cells and their anti‐tumor killing activity. Herein, we have analysed whether interaction of sHLA‐I with CD8 and/or different isoforms of killer Ig‐like receptors (KIR) induced secretion of transforming growth factor (TGF)‐β1. CD8⁺KIR^? NK cell clones secreted TGF‐β1 upon the interaction of sHLA‐I with CD8 molecule. sHLA‐Cw4 or sHLA‐Cw3 alleles engaging inhibitory isoforms of KIR, namely KIR2DL1 or KIR2DL2, strongly downregulated TGF‐β1 production elicited through CD8. On the other hand, sHLA‐Cw4 or sHLA‐Cw3 alleles induced secretion of TGF‐β1 by ligation of stimulatory KIR2DS1 or KIR2DS2 isoforms. TGF‐β1 strongly reduced NK cell‐mediated tumor cell lysis and production of pro‐inflammatory cytokines such as TNF‐α and IFN‐γ. Also, TGF‐β1 inhibited NK cell cytolysis induced by the engagement of stimulatory receptors including NKG2D, DNAM1, 2B4, CD69, NKp30, NKp44 and NKp46. The IL‐2‐dependent surface upregulation of some of these receptors was prevented by TGF‐β1. Furthermore, TGF‐β1 hampered IL‐2‐induced NK cell proliferation but not IL‐2‐mediated rescue from apoptosis of NK cells. Depletion of TGF‐β1 restored all the NK cell‐mediated functional activities analysed. Taken together these findings suggest that sHLA‐I antigens may downregulate the NK cell‐mediated innate response by inducing TGF‐β1 release.     

TGF‐β downregulates KLRG1 expression in mouse and human CD8+ T cells

The inhibitory receptor killer cell lectin‐like receptor G1 (KLRG1) and the integrin α_E (CD103) are expressed by CD8⁺ T cells and both are specific for E‐cadherin. However, KLRG1 ligation by E‐cadherin inhibits effector T‐cell function, whereas binding of CD103 to E‐cadherin enhances cell–cell interaction and promotes target cell lysis. Here, we demonstrate that KLRG1 and CD103 expression in CD8⁺ T cells from untreated and virus‐infected mice are mutually exclusive. Inverse correlation of KLRG1 and CD103 expression was also found in human CD8⁺ T cells‐infiltrating hepatocellular carcinomas. As TGF‐β is known to induce CD103 expression in CD8⁺ T cells, we examined whether this cytokine also regulates KLRG1 expression. Indeed, our data further reveal that TGF‐β signaling in mouse as well as in human CD8⁺ T cells downregulates KLRG1 expression. This finding provides a rationale for the reciprocal expression of KLRG1 and CD103 in different CD8⁺ T‐cell subsets. In addition, it points to the limitation of KLRG1 as a marker for terminally differentiated CD8⁺ T cells if lymphocytes from tissues expressing high levels of TGF‐β are analyzed.     

Submandibular gland morphogenesis: Stage‐specific expression of TGF‐α/EGF,IGF, TGF‐β, TNF,and IL‐6 signal transduction in normal embryonic mice and the phenotypic effects of TGF‐β2, TGF‐β3, and EGF‐r null mutations

Branching morphogenesis of the mouse submandibular gland (SMG) is dependent on cell‐cell conversations between and within epithelium and mesenchyme. Such conversations are typically mediated in other branching organs (lung, mammary glands, etc.) by hormones, growth factors, cytokines, and the like in such a way as to translate endocrine, autocrine, and paracrine signals into specific gene responses regulating cell division, apoptosis, and histodifferentiation. We report here the protein expression in embryonic SMGs of four signal transduction pathways: TGF‐α/EGF/EGF‐R; IGF‐II/IGF‐IR/IGF‐IIR; TGF‐βs and cognate receptors; TNF, IL‐6, and cognate receptors. Their in vivo spatiotemporal expression is correlated with specific stages of progressive SMG development and particular patterns of cell proliferation, apoptosis, and mucin expression. Functional necessity regarding several of these pathways was assessed in mice with relevant null mutations (TGF‐β2, TGF‐β₃, EGF‐R). Among many observations, the following seem of particular importance: (1) TGF‐α and EGF‐R, but not EGF, are found in the Initial and Pseudoglandular Stages of SMG development; (2) ductal and presumptive acini lumena formation was associated with apoptosis and TNF/TNF‐R1 signalling; (3) TGF‐β2 and TGF‐β3 null mice have normal SMG phenotypes, suggesting the presence of other pathways of mitostasis; (4) EGF‐R null mice displayed an abnormal SMG phenotype consisting of decreased branching. These and other findings provide insight into the design of future functional studies. Anat Rec 256:252–268, 1999. © 1999 Wiley‐Liss, Inc.     

IL‐1β induces thymic stromal lymphopoietin and an atopic dermatitis‐like phenotype in reconstructed healthy human epidermis

Atopic dermatitis (AD) is a common skin inflammatory disease characterized by the production of thymic stromal lymphopoietin (TSLP) and marked T_H2 polarization. Recent studies suggest that IL‐1β contributes to the development of AD skin inflammation. Here, we have investigated the impact of IL‐1β signalling on the epidermal homeostasis of both healthy subjects and AD patients [with functional filaggrin (FLG) alleles], with particular attention to TSLP production and keratinocyte differentiation. In healthy reconstructed human epidermis (RHE), IL‐1β promoted (i) robust secretion of TSLP in an NF‐κB‐dependent manner and (ii) a significant decrease in the expression of filaggrin and other proteins of the epidermal differentiation complex. These effects were prevented by treatment of RHE with the anti‐IL‐1β mAb canakinumab and by the IL‐1 receptor antagonist anakinra. Interestingly, RHE generated from AD donors behaved like that of healthy individuals and showed comparable responses to IL‐1β signals. Collectively, our results suggest that IL‐1β may be an early key mediator for the acquisition of an AD phenotype through induction of TSLP and alteration of the epidermal homeostasis. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Association of the −31C/T functional polymorphism in the interleukin‐1β gene with the intractability of Graves' disease and the proportion of T helper type 17 cells

Interleukin (IL)-1β is a proinflammatory cytokine and has been implicated in the pathogenesis of several autoimmune diseases. To evaluate the hypothesis that the functional −31C/T polymorphism (rs1143627) in the gene encoding IL-1β is associated with the intractability and the severity of autoimmune thyroid diseases, we genotyped this polymorphism in 64 patients with intractable Graves'' disease (GD), 28 GD patients in remission, 49 patients with Hashimoto''s disease (HD) who developed hypothyroidism (severe HD), 28 untreated euthyroid HD patients (mild HD) and 59 healthy volunteers. The −31T allele, which is related to the high producibility of IL-1β, was significantly more frequent in patients with intractable GD than in those with GD in remission (P = 0·0017; odds ratio 2·8; 95% confidence interval 1·5-5·3), although there was no difference in this frequency between two groups of HD patients. We showed additionally that the proportion of IL-17-producing T helper type 17 (Th17) cells, whose differentiation and proliferation are promoted by IL-1β, was higher in autoimmune thyroid disease patients with the T allele than in those with CC genotypes. In conclusion, our data indicated that the T allele of −31C/T polymorphism in the IL1B gene was involved in the intractability of GD, and this involvement may arise through the differentiation and proliferation of Th17 cells.     

MD‐2 is involved in the stimulation of matrix metalloproteinase‐1 expression by interferon‐γ and high glucose in mononuclear cells – a potential role of MD‐2 in Toll‐like receptor 4‐independent signalling

We reported recently that treatment of diabetic apolipoprotein E‐deficient mice with the Toll‐like receptor 4 (TLR4) antagonist Rs‐LPS, a lipopolysaccharide isolated from Rhodobacter sphaeroides, inhibited atherosclerosis. Since it is known that Rs‐LPS antagonizes TLR4 by targeting TLR4 co‐receptor MD‐2, this finding indicates that MD‐2 is a potential target for the treatment of atherosclerosis. In this study, we determined if MD‐2 is involved in the gene expression regulated by signalling pathways independent of TLR4. Given that interferon‐γ (IFNγ) and hyperglycaemia play key roles in atherosclerosis, we determined if MD‐2 is involved in IFN‐γ and high‐glucose‐regulated gene expression in mononuclear cells. Results showed that IFN‐γ and high glucose synergistically stimulated matrix metalloproteinase 1 (MMP‐1), a proteinase essential for vascular tissue remodelling and atherosclerosis, in U937 mononuclear cells, but Rs‐LPS inhibited the MMP‐1 stimulation. To provide more evidence for a role of MD‐2 in IFN‐γ‐stimulated MMP‐1, studies using antibodies and small interfering RNA demonstrated that MD‐2 blockade or knockdown attenuated the effect of IFN‐γ on MMP‐1. Furthermore, studies using PCR arrays showed that MD‐2 blockade had a similar effect as IFN‐γ receptor blockade on the inhibition of IFN‐γ‐stimulated pro‐inflammatory molecules. Although these findings indicate the involvement of MD‐2 in IFN‐γ signalling, we also observed that MD‐2 was up‐regulated by IFN‐γ and high glucose. We found that MD‐2 up‐regulation by IFN‐γ played an essential role in the synergistic effect of IFN‐γ and LPS on MMP‐1 expression. Taken together, these findings indicate that MD‐2 is involved in IFN‐γ signalling and IFN‐γ‐augmented MMP‐1 up‐regulation by LPS.     

IL13Rα2 expression identifies tissue‐resident IL‐22‐producing PLZF+ innate T cells in the human liver

Innate lymphocytes are selectively enriched in the liver where they have important roles in liver immunology. Murine studies have shown that type I NKT cells can promote liver inflammation, whereas type II NKT cells have an anti‐inflammatory role. In humans, type II NKT cells were found to accumulate in the gut during inflammation and IL13Rα2 was proposed as a marker for these cells. In the human liver, less is known about type I and II NKT cells. Here, we studied the phenotype and function of human liver T cells expressing IL13Rα2. We found that IL13Rα2 was expressed by around 1% of liver‐resident memory T cells but not on circulating T cells. In support of their innate‐like T‐cell character, the IL13Rα2⁺ T cells had higher expression of promyelocytic leukaemia zinc finger (PLZF) compared to IL13Rα2^? T cells and possessed the capacity to produce IL‐22. However, only a minority of human liver sulfatide‐reactive type II NKT cells expressed IL13Rα2. Collectively, these findings suggest that IL13Rα2 identifies tissue‐resident intrahepatic T cells with innate characteristics and the capacity to produce IL‐22.     

S100α and S100β proteins in human cutaneous sensory corpuscles: Effects of nerve and spinal cord injury

S100 protein in the vertebrate peripheral nervous system consists of homo- or heterodimers of S100α and S100β proteins, the first predominating in neurons and the second in glial cells. Recently, however, occurrence of S100β protein in neurons has been reported. The expression of S100 protein by Schwann cells, as well as their derivatives in sensory corpuscles, depends on the sensory axon (i.e., the Schwann cell–axon contact). The present study analyzed the distribution of S100α and S100β proteins in human cutaneous sensory corpuscles and the effects of peripheral or central sensory axon severance in the expression of these proteins. Simple or double immunohistochemistry was carried out using a panel of antibodies against S100α, S100β or S100α+β proteins, and the sections were examined by light or laser confocal scanning microscopy. Skin samples were obtained from normal subjects and patients with spinal cord injury, nerve entrapment, and nerve sections plus graft. The lamellar cells of Meissner corpuscles as well as the inner-core lamellae of the Pacinian corpuscles displayed strong immunoreactivity (IR) for all antigens examined, the most intense labeling being obtained for S100β protein. The pattern of immunostaining was unchanged after spinal cord injury, whereas the number of stained corpuscles as well as the intensity of IR for each antigen decreased in cutaneous sensory corpuscles after nerve injury, both entrapment and section plus graft. No evidence was found of axonal labeling. The present results provide evidence that Schwann-related cells in human cutaneous sensory corpuscles contain both S100α and S100β and that the expression of these proteins is dependent on the functional and structural integrity of sensory fibers. Anat. Rec. 251:351–359, 1998. © 1998 Wiley-Liss, Inc.     

Overexpression of cyclooxygenase‐2 in urothelial carcinoma in conjunction with tumor‐associated‐macrophage infiltration,hypoxia‐inducible factor‐1α expression,and tumor angiogenesis

This study examines whether the expression of cyclooxgenase‐2 (COX‐2) in urothelial carcinoma (UC) is associated with macrophage infiltration, hypoxia‐inducible factor‐1α (HIF‐1α) expression and angiogenesis. We investigated the expression of COX‐2 associated with HIF‐1α and performed double immunohistochemical analysis of 216 UCs for COX‐2 expression and the correlation with tumor‐associated‐macrophage (TAM) density and microvessel density (MVD) in situ. A high expression of COX‐2 was positively correlated with tumor invasiveness, histologic grade and HIF‐1α expression in UC (p<0.0001, p=0.003, p<0.0001, respectively). Quantification of double staining of COX‐2/CD34 and COX‐2/CD68 showed that a higher MVD and TAM density was found in COX‐2 high‐expression than in COX‐2 low‐expression tumor fields (p<0.0001). Adjacent to the principal of COX‐2 expression areas, MVD value and TAM density were significantly increased in HIF‐1α high‐expression specimens compared with HIF‐1α low‐expression ones (p<0.0001). Interestingly, our data revealed that high COX‐2 expression (p=0.002), high HIF‐1α expression (p<0.0001) and TAM density (p<0.0001) were all associated with high MVD value. Our results suggest that COX‐2 may produce a cooperative effect in promoting tumor progression and may be involved in the process of angiogenesis through increasing TAM infiltration or HIF‐1α regulation by hypoxia.     

Attenuated TGF‐β1 responsiveness of dendritic cells and their precursors in atopic dermatitis

The responsiveness of DCs and their precursors to transforming growth factor beta1 (TGF‐β1) affects the nature of differentiating DC subsets, which are essential for the severity of atopic dermatitis (AD). To evaluate TGF‐β signaling in monocytes and monocyte‐derived DCs of AD patients compared with that of controls, in vitro generated Langerhans cell (LC) like DCs, expression of TGF‐β receptors, phospho‐Smad2/3 and Smad7 were evaluated. Furthermore, TNF‐α expression and synergistic effects of TNF‐α upon TGF‐β signaling and DC generation were evaluated. We found LC‐like DC differentiation of monocytes from AD patients in response to TGF‐β1 was remarkably reduced and TGF‐β1 receptor expression was significantly lower compared with that of healthy controls. Attenuated TGF‐β1 responsiveness mirrored by lower phospho‐Smad2/3 expression after TGF‐β1 stimulation and higher expression of inhibitory Smad7 was observed in monocytes from AD patients. During DC generation, mRNA expression of Smad7 was relatively higher in LC‐like DCs of AD patients. Lower TNF‐α expression of monocytes from AD patients might further contribute to attenuated TGF‐β signaling in the disease since TNF‐α had synergistic effects on TGF‐β1 signaling and LC generation through mediating the degradation of Smad7. Our results demonstrate alleviated TGF‐β1 signaling together with the amount of soluble co‐factors might direct the nature of differentiating DCs.     

PKC,ERK/p38 MAP kinases and NF‐κB targeted signalling play a role in the expression and release of IL‐1β and CXCL8 in Porphyromonas gingivalis‐infected THP1 cells

Porphyromonas gingivalis is a keystone pathogen in periodontitis and is gaining importance in cardiovascular pathogenesis. Protease‐activated receptors (PARs), toll‐like receptors (TLRs) and nucleotide‐binding oligomerization domain (NOD) on monocytes recognize the structural components on P. gingivalis, inducing inflammatory intermediates. Here, we elucidate the modulation of PARs, TLRs, NODs, and the role of MAPK and NF‐κB in IL‐1β and CXCL8 release. THP1 cells were stimulated with P. gingivalis wild‐type W50 and its isogenic gingipain mutants: Rgp mutant E8 and Kgp mutant K1A. We observed modulation of PARs, TLRs, NOD, IL‐1β and CXCL8 expression by P. gingivalis. Gingipains hydrolyse IL‐1β and CXCL8, which is more evident for IL‐1β accumulation at 24 h. Inhibition of PKC (protein kinase C), p38 and ERK (extracellular signal‐regulated kinases) partially reduced P. gingivalis‐induced IL‐1β at 6 h, whereas PKC and ERK reduced CXCL8 at both 6 and 24 h. Following NF‐κB inhibition, P. gingivalis‐induced IL‐1β and CXCL8 were completely suppressed to basal levels. Overall, TLRs, PARs and NOD possibly act in synergy with PKC, MAPK ERK/p38 and NF‐κB in P. gingivalis‐induced IL‐1β and CXCL8 release from THP1 cells. These pro‐inflammatory cytokines could affect leucocytes in circulation and exacerbate other vascular inflammatory conditions such as atherosclerosis.     

Relationship of TGF‐β1 and Smad7 expression with decreased dendritic cell infiltration in liver gastrointestinal cancer metastasis

Immune responses and their modulation within the liver are critical to the outcome of liver malignancies. In late‐stage tumors, secreted TGF‐β promotes oncogenic functions and can confer tolerogenicity to some immune cells like DCs. The TGF‐β signaling pathway is involved in the control of several biological processes, including immunosurveillance. The aim of the present study was to assess CD1a⁺ and CD83⁺ DCs and to evaluate the impact of TGF‐β pathway on DCs maturation and distribution in the liver metastases from gastric and colorectal tumors. The percentage of CD83⁺ DCs in the liver tissue, surrounding metastasis and in the metastasis‐free liver was measured by flow cytometry, and TGF‐β levels were assessed in the tissue supernatant from the peritumoral liver after mononuclear cell isolation and in the sera of the same patients. CD1a⁺ and CD83⁺ DCs were observed in the tumor stroma and border. Out of 73 patients, there was cytoplasmic reactivity: of TGF‐β1 in 37 (50.7%); of Smad4 in 62 (84.9%); of Smad7 in 46 (63%), and of TGFβRII in 39 (53.4%) of the metastases. The TGF‐β1 expression in tumor cell cytoplasm correlated with low CD1a⁺ and low CD83⁺ DCs infiltration. The tissue levels of TGF‐β1, measured by ELISA in the supernatant were significantly increased in metastases than in normal liver. Using a two‐color FACS analysis, we found that the percentage of HLA‐DR⁺ CD83⁺ DCs in metastases was significantly decreased as compared with metastasis‐free liver tissue. In conclusion, the positive and negative correlations between the mediators from the TGF‐β pathway implied the existence of imbalance and suppression of this cytokine activity. The presence of increased TGF‐β expression by immunohistochemistry in tumor cells was confirmed by detection of increased TGF‐β tissue level in the supernatant from the tissue homogenate. The observation of low numbers of CD1a⁺ and CD83⁺ DCs in tumor stroma correlated with TGF‐β overexpression in tumor cells, a fact that well documents the immunosuppressive role of TGF‐β in metastasis development. The increased percentage of CD83⁺ DCs in the peritumoral tissue supposes that there could be active recruitment or local differentiation of DCs in the metastasis border, but inside the tumor the immune cells recruitment and activity are suppressed by TGF‐β and by other cytokines.     

BDCA3 expression is associated with high IFN‐λ production by CD34+‐derived dendritic cells generated in the presence of GM‐CSF,IL‐4, and/or TGF‐β

High BDCA3 expression is associated with a specific human IFN‐λ‐producing dendritic cell (DC) subset. However, BDCA3 has also been detected on other DC subsets. Thus far, development and function of BDCA3 expression on DCs remains poorly understood. Human Langerhans cells (LCs) and interstitial DCs (intDCs) can be generated in vitro by differentiation of CD34⁺ hematopoietic progenitors via distinct precursor DCs (preDCs), CD1a⁺ preDCs, and CD14⁺ preDCs, respectively. Here, we identified BDCA3 expression in this well‐known GM‐CSF/TNF‐α‐driven culture system and described the effect of IL‐4 and/or TGF‐β on induction of BDCA3 expression. In control or TGF‐β cultures, BDCA3 was only detected on CD14⁺ preDC‐derived intDCs. IL‐4 induced BDCA3 expression in both CD14⁺‐derived and CD1a⁺‐derived cultures. TGF‐β and IL‐4 together further increased CD14⁺‐derived and CD1a⁺‐derived BDCA3⁺ DC frequencies, which partly expressed CLEC9A, but were not identical to the BDCA3^highCLEC9A⁺ DC subset in vivo. Importantly, BDCA3⁺ cells, but not BDCA3^? cells, in this system produced high IFN‐λ levels upon polyinosinic:polycytidylic acid (polyI:C) stimulation. This culture system, in which BDCA3 expression is preferentially associated with the intDC lineage and IFN‐λ‐producing capacity, will greatly contribute to further research on the function and regulation of BDCA3 expression and IFN‐λ production by DCs.     

Increased frequency and function of KIR2DL1–3+ NK cells in primary HIV‐1 infection are determined by HLA‐C group haplotypes

The acquisition and maintenance of NK‐cell function is mediated by inhibitory killer‐cell immunoglobulin‐like receptors (KIRs) through their interaction with HLA class I molecules. Recently, HLA‐C expression levels were shown to be correlated with protection against multiple outcomes of HIV‐1 infection; however, the underlying mechanisms are poorly understood. As HLA‐C is the natural ligand for the inhibitory receptors KIR2DL1 and KIR2DL2/3, we sought to determine whether HLA‐C group haplotypes affect NK‐cell responses during primary HIV‐1 infection. The phenotypes and functional capacity of NK cells derived from HIV‐1‐positive and HIV‐1‐negative individuals were assessed (N = 42 and N = 40, respectively). HIV‐1 infection was associated with an increased frequency of KIR2DL1–3⁺ NK cells. Further analysis showed that KIR2DL1⁺ NK cells were selectively increased in individuals homozygous for HLA‐C2, while HLA‐C1‐homozygous individuals displayed increased proportions of KIR2DL2/3⁺ NK cells. KIR2DL1–3⁺ NK cells were furthermore more polyfunctional during primary HIV‐1 infection in individuals also encoding for their cognate HLA‐C group haplotypes, as measured by degranulation and IFN‐γ and TNF‐α production. These results identify a novel relationship between HLA‐C and KIR2DL⁺ NK‐cell subsets and demonstrate that HLA‐C‐mediated licensing modulates NK‐cell responses to primary HIV‐1 infection.     

Quantitative analysis of specific Th1/Th2 helper cell responses and IgG subtype antibodies in interferon‐α‐treated patients with chronic hepatitis C

This study aimed to characterise the immune mechanisms relevant to viral clearance in interferon (IFN)‐α‐treated chronic hepatitis C virus (HCV) infection. Proliferative responses of peripheral blood mononuclear cells from sustained complete IFN‐α therapy responders (n = 8), nonresponders (n = 13), untreated patients (n = 10), and healthy controls (n = 5) were measured retrospectively upon stimulation with recombinant HCV‐antigens (core, helicase, NS3, NS4, and NS5) and the secretion of IFN‐γ and interleukins (IL‐4, IL‐5, IL‐10, and IL‐12) were tested by ELISA. Furthermore, IFN‐γ as well as IL‐10 secreting CD4+ T cells were quantitated by intracellular cytokine staining. Anti‐HCV core and NS3‐specific IgG subclass antibodies were quantitated in the corresponding patient sera. Sustained therapy responders had more frequent and stronger NS3 and helicase‐specific cellular immune responses than nonresponders, untreated HCV patients and healthy controls. Independent from therapy outcome HCV‐stimulated T cells in IFN‐α treated patients secreted preferentially IFN‐γ The Th2 cytokines IL‐4 and IL‐10 were even decreased in nonresponders, while the IL‐12 secretion was not influenced. With respect to the humoral immune response sustained complete responders showed significantly reduced IFN‐γ independent anti‐HCV‐core and ‐NS3 IgG1 antibody synthesis. In conclusion, vigorous NS3‐specific T‐helper cell responses were associated with viral clearance in IFN‐α recipients; however, the cytokine and antibody analysis argues against a Th1/Th2 imbalance as a major factor that influence the therapy outcome. J. Med. Virol. 64:340–349, 2001. © 2001 Wiley‐Liss, Inc.