Interleukin-4 and Interferon-γ Inhibit Prostaglandin Production by Interleukin-1β-Stimulated Human Periodontal Ligament Fibroblasts

The purpose of the present study was to investigate the involvement of cyclooxygease-1 (COX-1) and cyclooxygenase-2 (COX-2) in prostaglandin (PG) production by human periodontal ligament (PDL) fibroblasts stimulated with a proinflammatory cytokine, inerleukin-1 (IL-1), and to examine the effect of interleukin-4 (IL-4), a Th2 cytokine, and interferon- (IFN-), a Th1 cytokine, on PG production by the cells. IL-1-stimulated PDL fibroblasts produced prostaglandin E₂ (PGE₂) in a time-dependent manner. Indomethacin, a non-selective COX-1/COX-2 inhibitor, and NS-398, a selective COX-2 inhibitor, completely inhibited PGE₂ production by IL-1-stimulated cells. Northern blot analysis showed that COX-2 mRNA was detected in IL-1-stimulated PDL cells, although not detected in unstimulated cells, while expression of COX-1 mRNA was in the same extent in both the cells. Dexamethasone inhibited COX-2 mRNA expression, COX activity and PGE₂ production in IL-1-stimulated cells. IL-4 and IFN- suppressed PGE₂ production by IL-1-stimulated PDL fibroblasts, but COX activity enhanced by IL-1 treatment was significantly inhibited by IL-4, not by IFN-. Northern blot analysis showed that IL-4 depressed COX-2 mRNA expression with no effect on COX-1 mRNA expression. On the other hand, IFN- had no effect on expression of COX-1 and -2 mRNA. These data suggest that COX-2 is primarily responsible for PGE₂ production by IL-1-stimulated human PDL fibroblasts and that IL-4 inhibited PGE₂ production by IL-1-stimulated PDL fibroblasts through down-regulation of COX-2 expression, while IFN- suppressed the PGE₂ production with no effect on COX-2 expression.     

Role of Interferon-γ in GVHD and GVL

Interferon （IFN）-γ, a potent proinflammatory cytokine produced by multiple types of cells （e.g., activated T, NK and NKT cells）, plays important and complex roles in both innate and adaptive immune responses. There may be a correlation between the IFN-γ level and GVHD severity in patients receiving allogeneic hematopoietic cell transplantation. However, such a correlation may just reflect the presence of large numbers of activated T cells, and does not necessarily imply a harmful role of IFN-γ in the pathogenesis of GVHD. There has been increasing experimental evidence that IFN-γ is not required and may even inhibit GVHD. Paradoxically, IFN-γ facilitates graft-versus-leukemic （GVL） effects. Thus, IFN-γ blockade is likely deleterious in patients after allogeneic hematopoietic cell transplantation, and not beneficial as previously suggested.     

Interferon-γ Expression in Natural Killer Cells and Natural Killer T Cells Is Suppressed in Early Pregnancy

Recent study has suggested that innate immune system might play an important role in pregnancy progression. In this study, to investigate whether NK cells and NKT cells, instead of T cells, are the dominant populations of peripheral blood in early pregnancy, flow cytometry was used to detect the percentage and intracellular cytokine expressions of T cells, NK cells, NKT cdls in peripheral blood of non-pregnant women and early pregnant women. In our result, the percentages of NK calls and NKT calls were significantly increased in pregnancy compared to non-pregnancy. However, the percentage of T cells was not changed. We did not detect the Th2-dominance of total lymphocytes or T cells in peripheral blood of early pregnant women and there were also no significant changes of type 1 and type 2 cytokines in T cells, but IFN-γ production in both NK and NKT cells was decreased in early pregnancy. These results suggest that the innate immune system including NK cells and NKT cells should play a pivotal role in pregnancy progression. Type 1/type 2 shift mechanisms in innate immune system during the human early pregnancy should be paid more attention.     

Relationship Between Interferon-γ, Interleukin-10, and Interleukin-12 Production in Chronic Hepatitis C and In Vitro Effects of Interferon-α

In the current study, increased interferon (IFN)-, interleukin (IL)-10, and IL-12 p40 serum levels were observed in patients with chronic hepatitis C (CHC) compared to controls. Patients also displayed an increased spontaneous IFN- release but a deficient peripheral blood mononuclear cells (PBMC) IFN- production following stimulation with Staphylococcus aureus Cowan I strain (SAC). No difference was found with reference to spontaneous or phytohaemagglutinin (PHA)-induced IL-10 release between patients and controls, whereas a higher IL-12 p70 and IL-12 p40 secretion triggered by SAC was observed in patients. Moreover, IL-12 p40/p70 ratio following SAC stimulation was higher in patients compared to controls and a negative correlation was found between this ratio and IFN- amounts. Recombinant IL-12 (rIL-12) as well as neutralizing anti-IL-10 monoclonal antibodies (mAbs) were able to restore the compromised IFN- production. Of note, anti-IL-10 supplementation induced a lower IL-12 p40/p70 ratio in HCV subjects as compared to controls. Finally, IFN- upregulated in vitro IFN-, IL-10, and IL-12 p70 release but not IL-12 p40 secretion, this giving rise to a normalization of IL-12 p40/p70 ratio. The data suggest the occurrence of an enhanced responsiveness to IL-10 modulating effects, likely mediated by an imbalance of IL-12 p40/p70 ratio, in chronic HCV infection. Cytokine balance restoration might thus contribute to achieve therapeutical results in chronic hepatitis C.     

Nicotinamide and 3-Aminobenzamide Reduce Interferon-γ -Induced Class II MHC (HLA-DR and -DP) Molecule Expression on Cultured Human Endothelial Cells and Fibroblasts

Abstract

We investigated the effects of nicotinamide and 3-aminobenzamide, known as inhibitors of poly(ADP-ribose) synthetase, on the expression of interferon-γ (IFN-γ) -induced class I and II major histocompatibility complex (MHC) molecules on the surface of cultured human umbilical vein endothelial cells (HUVEC) and human dermal fibroblasts (HDF). Indirect immunofluorescent staining on HUVEC and HDF was performed using monoclonal antibodies against class I MHC (HLA-A, B, C) and class II MHC (HLA-DR, HLA-DP and HLA-DQ) molecules, and then the expression of these molecules was determined using a fluorescence flow cytometry. Human recombinant IFN-γ (100 U/ml) increased the expression of HLA-A, B, C molecules, and induced the expression of HLA-DR molecules and, to a lesser extent, of HLA-DP on both HUVEC and HDF. HLA-DQ molecules were not induced by IFN-γ on either cell type. Nicotinamide and 3-aminobenzamide in the concentration great-er than or equal to 1 mM reduced the IFN-γ -induced expression of HLA-DR and HLA-DP on both HUVEC and HDF, whereas neither agent in the concentration of up to 10 mM affected the IFN-γ -induced increase in HLA-A, B, C molecule expression. These data suggest that nicotinamide and 3-aminobenzamide suppress antigen presenting function of class II MHC positive endothelial cells and fibroblasts at the site of tissue inflammation.     

In Vitro Effects of Benzophenone-2 and Octyl-Methoxycinnamate on the Production of Interferon-γ and Interleukin-10 by Murine Splenocytes

Chemical ultraviolet light absorbers (UV-filters) are nowadays widely used in cosmetic and plastic industry. Recent in vitro and in vivo studies have reported that certain chemical UV-filters possess estrogenic activity raising the question of whether these compounds are safe to human health. Work on estrogenic effects of these compounds, however, has focused mostly on reproductive organs, and as the presence of estrogen receptors has been identified in several cells of the immune system, UV screens also may have a great impact on immunity. Thus, we have studied the in vitro effects of two widely used UV-filters—benzophenone-2 (BP-2) and octyl-methoxycinnamate (OMC)—on the production of interferon (IFN)-γ and interleukin (IL)-10, two cytokines representing Th1- and Th2-type response, respectively, by activated murine splenocytes. Cells were cultured on 48-well plastic plates and stimulated with 12-miristate 13-acetate (PMA) (5 ng/ml) and ionomycin (50 ng/ml) in the presence of different concentrations (10^?5–10^?8M) of the studied substances or 17β-estradiol (E2). After 48 hr incubation the supernatants were collected and the levels of IFN-γ and IL-10 were measured using immunoenzymatic assay. Our results show that BP-2 and OMC at high concentrations (10^?5M) shifted the Th1/Th2 balance toward a Th2 response (lower IFN-γ production and higher IL-10). These effects were comparable to those of E2. Our results clearly show that UV-screens at high doses also may possess immunomodulatory effects some of which resemble those of E2.     

Interferon-γ Protects First-Trimester Decidual Cells against Aberrant Matrix Metalloproteinases 1, 3, and 9 Expression in Preeclampsia

Human extravillous trophoblast (EVT) invades the decidua via integrin receptors and subsequently degrades extracellular matrix proteins. In preeclampsia (PE), shallow EVT invasion elicits incomplete spiral artery remodeling, causing reduced uteroplacental blood flow. Previous studies show that preeclamptic decidual cells, but not interstitial EVTs, display higher levels of extracellular matrix–degrading matrix metalloproteinase (MMP)-9, but not MMP-2. Herein, we extend our previous PE-related assessment of MMP-2 and MMP-9 to include MMP-1, which preferentially degrades fibrillar collagens, and MMP-3, which can initiate a local proteolytic cascade. In human first-trimester decidual cells incubated with estradiol, tumor necrosis factor-α (TNF-α) significantly enhanced MMP-1, MMP-3, and MMP-9 mRNA and protein levels and activity measured by real-time quantitative RT-PCR, ELISA, immunoblotting, and zymography, respectively. In contrast, interferon γ (IFN-γ) reversed these effects and medroxyprogesterone acetate elicited further reversal. Immunoblotting revealed that p38 mitogen-activated protein kinase signaling mediated TNF-α enhancement of MMP-1, MMP-3, and MMP-9, whereas IFN-γ inhibited p38 mitogen-activated protein kinase phosphorylation. Unlike highly regulated MMP-1, MMP-3, and MMP-9, MMP-2 mRNA and protein expression was constitutive in decidual cells. Because inflammation underlies PE-associated shallow EVT invasion, these results suggest that excess macrophage-derived TNF-α augments expression of MMP-1, MMP-3, and MMP-9 in decidual cells to interfere with normal stepwise EVT invasion of the decidua. In contrast, decidual natural killer cell–derived IFN-γ reverses such TNF-α–induced MMPs to protect against PE.Preeclampsia (PE) is a multifactorial disease that affects 6% to 8% of pregnancies in the United States, is responsible for nearly 8% of maternal deaths, and is a leading cause of perinatal morbidity and mortality. Severe PE is a major indication for early, medically indicated preterm birth.¹ The diagnosis of PE is usually made after 20 weeks by the appearance of hypertension and proteinuria (maternal syndrome).¹During the first 20 weeks of gestation, extravillous trophoblasts (EVTs) arise from cytotrophoblast at the tips of placental anchoring villi and invade the decidua and upper third of the myometrium. As they navigate through the decidua, EVTs enter and facilitate remodeling of spiral arteries and arterioles into large-bore, low-resistance vessels that increase uteroplacental blood flow to the intervillous space requisite for fetal growth and development.^2,3 The onset of PE is strongly associated with shallow decidual EVT invasion, which leads to incomplete vascular transformation and reduced uteroplacental blood flow. The resulting hypoxic placenta⁴ secretes several putative inducers of endothelial cell activation and angiogenesis (eg, soluble flt-1 and endoglin) into the maternal circulation that elicits vascular damage,^5,6 leading to the maternal syndrome.¹Invasion of the decidua by EVT involves sequential attachment to adhesion molecules, followed by their degradation. Relevant integrin (ITG) heterodimers include ITG-α1/ITG-β1 and ITG-α5/ITG-β1, which recognize laminin/collagen IV and fibronectin, respectively, in the decidual extracellular matrix (ECM),^7–9 as well as vascular endothelial cadherin, an endothelial cell receptor.¹⁰ In addition to newly synthesized basement membrane–type proteins, the decidual ECM also contains significant residual interstitial collagens.¹¹ Degradation of the ECM scaffolding structure is mediated principally by matrix metalloproteinases (MMPs), a family of zinc-requiring enzymes that includes collagenases, gelatinases, and stromelysins.¹² Tissue inhibitors of MMPs (TIMPs) regulate MMP catalytic activity.¹³ The MMPs act in concert with urokinase-type plasminogen activator (uPA) and its specific inhibitor, plasminogen activator inhibitor-1 (PAI-1).¹⁴Previously, our laboratory compared immunostaining of the decidua from women with PE versus gestational age–matched control decidua for the presence of the basement membrane–degrading gelatinases, MMP-2 and MMP-9, as well as their respective inhibitors, TIMP-1 and TIMP-2, and found that PE is accompanied by a significant increase in MMP-9 levels in decidual cells, but not in interstitial EVTs. Unlike MMP-9, no PE-related changes in immunostaining were observed for either MMP-2 or TIMP-1 or TIMP-2 in either decidual cells or interstitial EVTs.¹⁵ Significant subsets of PE are associated with underlying maternal infections and/or inflammation,¹⁶ accompanied by an excess of decidual macrophages^17–20 that are likely sources of elevated levels of the proinflammatory cytokines IL-1β and tumor necrosis factor-α (TNF-α).²¹Consistent with the in situ observations described above and strong evidence that the pathogenesis of most cases of PE are initiated in early pregnancy,¹ we found that incubation of primary leukocyte-free, first-trimester human decidual cells with either IL-1β or TNF-α markedly enhanced MMP-9 mRNA and protein expression, unaccompanied by significant changes in either MMP-2 or TIMP-1 or TIMP-2 mRNA and protein expression.¹⁵The current study extends our previous PE-related assessment of MMP-2 and MMP-9 to include MMP-1, which preferentially degrades fibrillar collagens, and MMP-3, which can initiate a local proteolytic cascade by degrading a wide array of ECM proteins and by activating the secreted zymogenic form of other MMPs, such as pro–MMP-1 and pro–MMP-9.^13,22 We found the following using a two-tiered approach of integrating in situ with in vitro observations: immunoreactive MMP-1 and MMP-3 levels were compared in decidual cells and interstitial EVTs of decidual placental sections from women with PE versus gestational age–matched controls: MMP-1, MMP-3, as well as MMP-2 and MMP-9, were measured in the conditioned medium of primary, leukocyte-free, first-trimester human decidual cells incubated in parallel with estradiol (E₂), which was used as the control incubation for E₂ + medroxyprogesterone acetate (MPA) to mimic the pregnant steroid milieu. The steroids were added alone or with either TNF-α or interferon γ (IFN-γ) or TNF-α + IFN-γ. Inclusion of IFN-γ, a primary decidual natural killer (dNK) cell product,²³ was prompted by our recent observations that co-incubation of first-trimester human decidual cells with IFN-γ and either IL-1β or TNF-α synergistically enhances expression of two chemokines, interferon gamma-induced protein 10 (IP-10; alias CXCL10) and interferon-inducible T cell alpha chemoattractant (ITAC; alias CXCL11), that can selectively recruit the peripheral C-X-C chemokine receptor 3–expressing CD56^bright CD16(−) NK cell population to the decidua,²⁴ where they mediate several pregnancy protective effects.^25–27     

Human Rhinovirus-induced Proinflammatory Cytokine and Interferon-β Responses in Nasal Epithelial Cells From Chronic Rhinosinusitis Patients

Purpose

Asthma exacerbation from human rhinovirus (HRV) infection is associated with deficient antiviral interferon (IFN) secretion. Although chronic rhinosinusitis (CRS), an inflammatory upper airway disease, is closely linked to asthma, IFN-β responses to HRV infections in human nasal epithelial cells (HNECs) from CRS patients remain to be studied. We evaluated inflammatory and antiviral responses to HRV infection in HNECs from CRS patients.

Methods

HNECs, isolated from turbinate tissue of 13 patients with CRS and 14 non-CRS controls, were infected with HRV16 for 4 hours. The HRV titer, LDH activity, production of proinflammatory cytokines and IFN-β proteins, and expression levels of RIG-I and MDA5 mRNA were assessed at 8, 24, and 48 hours after HRV16 infection.

Results

The reduction in viral titer was slightly delayed in the CRS group compared to the non-CRS control group. IL-6 and IL-8 were significantly increased to a similar extent in both groups after HRV infection. In the control group, IFN-β production and MDA5 mRNA expression were significantly increased at 8 and 24 hours after HRV16 infection, respectively. By contrast, in the CRS group, IFN-β was not induced by HRV infection; however, HRV-induced MDA5 mRNA expression was increased, but the increase was slightly delayed compared to the non-CRS control group. The RIG-I mRNA level was not significantly increased by HRV16 infection in either group.

Conclusions

HRV-induced secretion of proinflammatory cytokines in CRS patients was not different from that in the non-CRS controls. However, reductions in viral titer, IFN-β secretion, and MDA5 mRNA expression in response to HRV infection in CRS patients were slightly impaired compared to those in the controls, suggesting that HRV clearance in CRS patients might be slightly deficient.     

Crucial Role of CD4+CD 25+ FOXP3+ T Regulatory Cell,Interferon-γ and Interleukin-16 in Malignant and Tuberculous Pleural Effusions

The differential diagnosis between malignant and tuberculous exudative pleural effusions is an important clinical problem. The aim of current study is to evaluate the frequencies of T-regulatory cells (Treg) on the basis of distinct phenotypes in the differential diagnosis between malignant and tuberculous pleural effusion. In addition, to evaluate Interferon-gamma (IFN- γ) and interleukin-16 (IL-16) levels and their correlation to Treg cells in malignant and tuberculous pleural effusions. Sixty patients with pleural effusion (26 tuberculous and 34 malignant) and 20 healthy controls were included in the study. Pleural fluid and peripheral blood were assessed for frequencies of T regs, IL-16, and IFN-γ. Pleural effusions from both tuberculous and malignant groups represented significantly higher levels (more in TB) for the following cell populations than peripheral blood: total lymphocytes, CD3+lymphocyte, CD4+CD25+lymphocyte and Treg (CD4+ CD25+FoxP3+). Levels of IL-16 and IFN-γ in tuberculous group were significantly higher than that in malignant group. Regulatory T cells, INF-γ and IL-16 are new important tools for differentiation between tuberculous and malignant pleural effusion.     

Kinetics of Receptor-Mediated Uptake and Processing of Interferon-α2a and Tumor Necrosis Factor-α by Human Tumor Cells

Abstract

The kinetics of uptake and processing of recombinant human interferon-a₂a (IFN) and recombinant human tumor necrosis factor-a (TNF) were studied in human epithelial rumor cell lines differing in sensitivity to growth inhibition by IFN and TNF. Concentrations of [¹²⁵I]IFN or [¹²⁵I]TNF at the cell surface and internalized by confluent cell monolayers incubated at 37°C were measured as a function of time. Cells incubated with [¹²⁵I]IFN exhibited transient maxima of surface-associated and internalized [^I25I]IFN after 1-2 hr of incubation followed by a steady-state attained after approximately 6 hr of exposure to [¹²⁵I]IFN. Concentration of [¹²⁵I]TNF associated with the plasma membrane displayed a maximum within 20 min of incubation. Internalized radioactivity increased with time and did not achieve a steady state. We analyzed the time-dependent concentrations of membrane-associated and internalized cytokines by use of a compartmental model. This model describes changes in concentrations of free surface receptors, of ligand-receptor complex at the membrane and of internalized ligand and contains a term for receptor recycling. The rate constants for concentration changes were evaluated by fitting model functions to data. The best fits for IFN were obtained without receptor recycling. The best-fit values for the endo-cytotic rate constant (k_tlFN) varied among cell lines from 2.4x10^?4 to 7.8 x10^?4 sec^?1. To obtain fits to time-dependent concentrations of surface-associated and internalized [¹²⁵I]TNF, introduction of a term for receptor recycling was required. Best-fit values for k, _TNF ranged among cell lines from 8.4x10^?4 to 2.5x10^?3 sec^?1. For every cell line, the value of k_lTNF was larger than the value of k_clFN. We tested the significance of these differences by substituting K.IFN ^tor K.TNT ^as fixed parameters in fits to data for TNF and v.v., respectively. Under these conditions, fits were significantly worse. Our data indicate that recycling is insignificant in kinetics of Type-I IFN receptor; recycling is necessary to explain the kinetics of TNF receptor. Upon binding, TNF is taken up by cells faster than IFN and is eliminated from cells more slowly than IFN.     

Effects of the Homeopathic Preparation Engystol on Interferon-γ Production by Human T-Lymphocytes

There is a growing interest in complementary medical practices, but few studies have investigated mechanisms behind the possible benefits. The effects of the homeopathic preparation Engystol on interferon-γ producing T-lymphocytes were studied in vitro. Lymphocytes were isolated from 30 healthy human volunteers and the percentage of interferon-γ producing cells was analysed by fluorescence activated cell sorting. Cells were treated with NaCl (control) or Engystol at concentrations from undiluted to 2%. All concentrations of Engystol increased the percentage of interferon-γ producing lymphocytes significantly, from a mean of 20.9% ± 10.5% to over 24%. There was no dose‐dependence of the effect at the concentrations tested.     

Alternative Reprogramming of M1/M2 Phenotype of Mouse Peritoneal Macrophages In Vitro with Interferon-γ and Interleukin-4

An important role in the development of the immune response is played by macrophages that acquire either anti-inflammatory M1 or anti-inflammatory M2 phenotype depending on their microenvironment. The possibility of targeted reprogramming of the initial M2 macrophage phenotype towards M1 phenotype and vice versa using macrophage reprogramming factors IFN-γ and IL-4, respectively, was demonstrated. We showed that macrophages of genetically different mouse strains did not practically differ by their reprogramming capacity. Our findings suggest that macrophage programming not only participates in the triggering of the immune response, but also can ensure plasticity of functional activity during the developing response.     

Role of Natural Interferon-α Producing Cells (Plasmacytoid Dendritic Cells) in Autoimmunity

The type I interferons (IFNs) have antiviral, cytostatic and prominent immunomodulatory effects, which all are of great importance during viral infections. However, prolonged exposure of the immune system to type I IFN can break tolerance and initiate an autoimmune reaction, eventually leading to autoimmune disease. Recent observations in patients with systemic lupus erythematosus (SLE) have revealed that such individuals have endogenous IFN-α inducers, causing an ongoing IFN-α production and consequently a continuous stimulation of the immune system. These IFN-α inducers consist of small immune complexes (IC) containing DNA or RNA and act on the principal IFN-α producing cell, the natural IFN-α producing cell (NIPC), also termed the plasmacytoid dendritic cell (PDC). The NIPC/PDC is a key cell in both the innate and adaptive immune response but can also, either directly or via produced IFN-α, have a pivotal role in autoimmunity. In this review we summarize recent data concerning NIPC/PDC, including their activation, regulation, function and possible role in autoimmune diseases, especially SLE.     

Interferon-γ for treatment of severe atopic eczema in two children

Two 4- and 5-year-old children suffering from refractory atopic dermatitis were treated with recombinant interferon- (rIFN-). rIFN- was injected at 50 g subcutaneously three times a week in the first child for 3 weeks, followed by three times 25 g in week 4. In the other child two treatment courses of 4 weeks were given after a break of 2 weeks. Therapy was well tolerated. In child one reductions in eczematous body surface and severity of lesions were observed, while no beneficial effect was seen in the other. Clinical chemistry data remained unchanged. Immunological studies performed in parallel showed a decrease in total serum IgE of 50% in child 1, a decrease in spontaneous in vitro IgE production, an increase in in vitro production of interleukin-6, and a normalization of previously decreased in vitro lymphocyte responses to several mitogens. While marked immunological changes were noted during IFN- treatment, clinical benefits were not encouraging. Diminished IFN- production has been claimed to be a major pathogenic factor in atopic eczema. Our results indicate that the pathogenesis is more complex. Clinically, we were unable to confirm previous observations in adults. Further studies are needed before IFN- can be recommended for therapy of pediatric atopic eczema.Abbreviations IFN- interferon- - IL interleukin     

In Vitro Induction of Allergen-Specific Interleukin-10-Producing Regulatory B Cell Responses by Interferon-γ in Non-Immunoglobulin E-Mediated Milk Allergy

Purpose

Specific oral immunotherapy (SOIT) using interferon-γ (IFN-γ) has been successful as a food allergy treatment. Interleukin-10 (IL-10)-producing regulatory B cells (Br1s) play a role in immune tolerance to food allergens. In addition, IFN-γ shows tolerogenic effects on allergen-induced Br1 responses.

Methods

Eleven patients that were allergic to cow''s milk and 12 milk-tolerant subjects were selected by double-blind placebo-controlled food challenge (DBPCFC) and clinical characteristics. The immunomodulatory effects of IFN-γ on allergen-specific Br1 responses were evaluated in 6 milk allergy patients and 8 milk-tolerant subjects. Peripheral blood mononuclear cells (PBMCs) from subjects were stimulated with casein and/or IFN-γ and analyzed by flow cytometry.

Results

IFN-γ had no effect on total cell counts or the proportion of Br1 cells in PBMCs. IFN-γ stimulation did not change total Br1 cell counts or the percentage of Br1s among CD5(+) B cells in the milk allergy or the milk-tolerant groups. In the milk allergy group, Br1 counts were not different between the control and the casein stimulation but significantly increased in the IFN-γ + casein stimulated cells, and the Br1 fractions were decreased after casein stimulation and recovered in the addition of IFN-γ for stimulation. In the milk-tolerant group, Br1 counts increased in the casein stimulated cells and in the IFN-γ + casein stimulated cells, but the increase was significantly less when IFN-γ was added, and the Br1 fractions were increased after casein stimulation and IFN-γ + casein stimulation, that was not significant when IFN-γ was added.

Conclusions

IFN-γ-induced allergen-specific Br1 responses in the PBMCs of milk allergy patients play a role in milk allergen-specific tolerance induction in vitro. Further investigations into the molecular immunological mechanisms underlying the induction of allergen-specific Br1 responses are needed.     

Comparison of the Ultrastructural and Immunophenotypic Characteristics of Human Umbilical Cord-derived Mesenchymal Stromal Cells and in Situ Cells in Wharton’s Jelly

ABSTRACT

The umbilical cord contains mucinous connective tissue, called Wharton's jelly. It consists of stromal cells, collagen fibers, and amorphous ground substances composed of proteoglycan. Recently, these stromal cells have been redefined as a new cell therapy source, named human umbilical cord-derived mesenchymal stromal cells (hUCMSCs). However, there are few studies on the ultrastructural features and immune-phenotypic characteristics of isolated hUCMSCs and comparisons with the cells found in original cord tissues. In this study, the authors describe and compare the phenotypic characteristics of hUCMSCs with cells in the umbilical cord in order to know the kinds of cells and ultrastructural changes. Isolated hUCMSCs showed similar ultrastructure with few structural differences from in situ stromal cells, and they are relatively homogenous and well-developed mesenchymal cells that demonstrate a myofibroblastic phenotype.