TNF downmodulates the function of human CD4+CD25hi T-regulatory cells

CD4+CD25+ T-regulatory cells (Tregs) play an essential role in maintaining immunologic homeostasis and preventing autoimmunity. However, little is known about the exogenous factors that regulate their differentiation and function. Here, we report that TNF inhibits the suppressive function of both naturally occurring CD4+CD25+ Tregs and TGFbeta1-induced CD4+CD25+ T-regulatory cells. The mechanism of this inhibition involves signaling through TNFRII that is constitutively expressed selectively on unstimulated Tregs and that is up-regulated by TNF. TNF-mediated inhibition of suppressive function is related to a decrease in FoxP3 mRNA and protein expression by the Tregs. Notably, CD4+CD25hi Tregs isolated from patients with active rheumatoid arthritis (RA) expressed reduced levels of FoxP3 mRNA and protein and poorly suppressed the proliferation and cytokine secretion of CD4+ effector T cells in vitro. Treatment with anti-TNF antibody (infliximab) increased FOXP3 mRNA and protein expression by CD4+CD25hi Tregs and restored their suppressive function. Thus, TNF has a novel action in modulating autoimmunity, by inhibiting CD4+CD25+ Treg activity.

Deficient CD4+CD25high T Regulatory Cell Function in Patients with Active Systemic Lupus Erythematosus

CD4(+)CD25(+) T regulatory cells (Tregs) play an essential role in maintaining immunologic homeostasis and preventing autoimmunity. Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by a loss of tolerance to nuclear components. We hypothesized that altered function of CD4(+)CD25(high) Tregs might play a role in the breakdown of immunologic self-tolerance in patients with SLE. In this study, we report a significant decrease in the suppressive function of CD4(+)CD25(high) Tregs from peripheral blood of patients with active SLE as compared with normal donors and patients with inactive SLE. Notably, CD4(+)CD25(high) Tregs isolated from patients with active SLE expressed reduced levels of FoxP3 mRNA and protein and poorly suppressed the proliferation and cytokine secretion of CD4(+) effector T cells in vitro. In contrast, the expression of FoxP3 mRNA and protein and in vitro suppression of the proliferation of CD4(+) effector T cells by Tregs isolated from inactive SLE patients, was comparable to that of normal individuals. In vitro activation of CD4(+)CD25(high) Tregs from patients with active SLE increased FoxP3 mRNA and protein expression and restored their suppressive function. These data are the first to demonstrate a reversible defect in CD4(+)CD25(high) Treg function in patients with active SLE, and suggest that strategies to enhance the function of these cells might benefit patients with this autoimmune disease.

Cadherin-11 provides specific cellular adhesion between fibroblast-like synoviocytes

Cadherins are integral membrane proteins expressed in tissue-restricted patterns that mediate homophilic intercellular adhesion. During development, they orchestrate tissue morphogenesis and, in the adult, they determine tissue integrity and architecture. The synovial lining is a condensation of fibroblast-like synoviocytes (FLS) and macrophages one to three cells thick. These cells are embedded within the extracellular matrix, but the structure is neither an epithelium nor an endothelium. Previously, the basis for organization of the synovium into a tissue was unknown. Here, we cloned cadherin-11 from human rheumatoid arthritis (RA)-derived FLS. We developed L cell transfectants expressing cadherin-11, cadherin-11 fusion proteins, and anti–cadherin-11 mAb. Cadherin-11 was found to be expressed mainly in the synovial lining by immunohistologic staining of human synovium. FLS adhered to cadherin-11–Fc, and transfection of cadherin-11 conferred the formation of tissue-like sheets and lining-like structures upon fibroblasts in vitro. These findings support a key role for cadherin-11 in the specific adhesion of FLS and in synovial tissue organization and behavior in health and RA.

Objective and subjective sleep disturbances in patients with systemic lupus erythematosus

OBJECTIVE

To assess objective and subjective evidence of sleep disorders in patients with systemic lupus erythematosus (SLE) and to examine correlations between parameters of lupus activity, depression, and sleep disturbances.

METHODS

Fourteen SLE patients and 11 normal control subjects of similar age underwent all-night polysomnography on 3 consecutive nights. The patients and controls were also evaluated for daytime sleepiness by the Multiple Sleep Latency Test and completed a sleep disorders questionnaire and the Beck Depression Inventory.

RESULTS

The polysomnographic data showed that sleep in SLE patients was characterized by respiratory and movement disorders. These intrinsic primary sleep disorders are related to the symptom of restless, poor sleep at night. Lupus patients were more sleepy during the day, and their sleepiness was related to sleep fragmentation, with more arousals and stage transitions than the control group. Disease activity was associated with decreases in sleep efficiency and delta sleep and with increases in sleep fragmentation. Depression was not correlated with the activity of the disease.

CONCLUSION

There is an enhanced presence of sleep disorders in patients with SLE. The most frequent primary sleep disorders are respiratory and movement disorders.

Efficacy and Safety of Anti-Interleukin-20 Monoclonal Antibody in Patients With Rheumatoid Arthritis: A Randomized Phase IIa Trial

OBJECTIVE

Interleukin-20 (IL-20) is implicated in the pathogenesis of rheumatoid arthritis (RA). The efficacy, safety, and tolerability of NNC0109-0012, a selective anti-IL-20 recombinant human monoclonal antibody (mAb), were assessed in patients with active RA who had an inadequate response to methotrexate therapy.

METHODS

Sixty-seven patients with RA were enrolled and randomized (2:1) to receive NNC0109-0012 (3 mg/kg per week, subcutaneously) or placebo in a phase IIa, double-blind, 12-week trial with a 13-week followup. The primary end point was change in the Disease Activity Score in 28 joints based on C-reactive protein level (DAS28-CRP) from baseline to week 12.

RESULTS

In patients treated with NNC0109-0012, the primary end point, improvement in the DAS28-CRP at week 12, was achieved (estimated difference -0.88; P = 0.02), with significant improvement starting at week 1. A greater response was observed in seropositive patients (estimated difference -1.66; P < 0.001), which was sustained through 13 weeks of followup, whereas no improvement was noted in patients with seronegative RA. A significant proportion of patients with seropositive RA receiving NNC0109-0012, compared to those receiving placebo, achieved treatment responses according to the American College of Rheumatology 20% (ACR20) (59% versus 21%), ACR50 (48% versus 14%), and ACR70 (35% versus 0%) levels of improvement, and showed greater improvements in the Health Assessment Questionnaire disability index (P = 0.047). The most frequent adverse events reported with NNC0109-0012 were injection site reactions and infections (e.g., herpes, nasopharyngitis, respiratory, and urinary). No serious infections or discontinuations associated with NNC0109-0012 were observed.

CONCLUSION

In this phase IIa trial, treatment with NNC0109-0012 (anti-IL-20 mAb) was effective in patients with seropositive RA as early as week 1, with further improvements to week 12. No safety or tolerability concerns were identified with weekly NNC0109-0012 administration.

An N-linked glycan modulates the interaction between the CD1d heavy chain and beta 2-microglobulin

Human CD1d molecules consist of a transmembrane CD1 (cluster of differentiation 1) heavy chain in association with beta(2)-microglobulin (beta(2)m). Assembly occurs in the endoplasmic reticulum (ER) and involves the initial glycan-dependent association of the free heavy chain with calreticulin and calnexin and the thiol oxidoreductase ERp57. Folding and disulfide bond formation within the heavy chain occurs prior to beta(2)m binding. There are four N-linked glycans on the CD1d heavy chain, and we mutated them individually to ascertain their importance for the assembly and function of CD1d-beta(2)m heterodimers. None of the four were indispensable for assembly or the ability to bind alpha-galactosyl ceramide and to present it to human NKT cells. Nor were any required for the CD1d molecule to bind and present alpha-galactosyl ceramide after lysosomal processing of a precursor lipid, galactosyl-(alpha1-2)-galactosyl ceramide. However, one glycan, glycan 2 at Asn-42, proved to be of particular importance for the stability of the CD1d-beta(2)m heterodimer. A mutant CD1d heavy chain lacking glycan 2 assembled with beta(2)m and transported from the ER more rapidly than wild-type CD1d and dissociated more readily from beta(2)m upon exposure to detergents. A mutant expressing only glycan 1 dissociated completely from beta(2)m upon exposure to the detergent Triton X-100, whereas a mutant expressing only glycan 2 at Asn-42 was more stable. In addition, glycan 2 was not processed efficiently to the complex form in mature wild-type CD1d molecules. Modeling the glycans on the published structure indicated that glycan 2 interacts significantly with both the CD1d heavy chain and beta(2)m, which may explain these unusual properties.

A pilot study of the use of 2-[18F]-fluoro-2-deoxy-D-glucose-positron emission tomography to assess the distribution of activated lymphocytes in patients with systemic lupus erythematosus

OBJECTIVE

The 2-[(18)F]-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) technique provides information on uptake and metabolism of glucose in various tissues. Compared with resting cells, activated lymphocytes take up radioactively labeled glucose analog at a higher rate, which makes it possible to identify lymphoid organs with higher concentrations of activated lymphocytes. This study was undertaken to compare the pattern of PET images and quantitative FDG uptake in lymphoid organs of patients with active systemic lupus erythematosus (SLE) versus patients with inactive SLE and to correlate these findings with peripheral blood lymphocyte phenotypes.

METHODS

Ten patients with active SLE and 9 patients with inactive SLE were studied. FDG-PET images were obtained from the inguinal region to above the ear, starting at 60 minutes after injection of FDG. Standardized uptake values using lean body mass were determined over areas of interest.

RESULTS

Both patients with active lupus and those with inactive lupus had increased FDG uptake in lymph nodes when compared with healthy volunteers, and there was no statistically significant difference between the 2 groups of lupus patients. Thymic uptake was demonstrated in 5 of 10 patients with active lupus compared with 0 of 9 patients with inactive disease. Three of the 5 patients with active SLE who were over 29 years of age had thymic uptake. Of the activation markers tested, only the CD3/CD71 population of cells was significantly different between the patient groups, with an increased percentage in the active disease group (P = 0.0247).

CONCLUSION

Increased FDG uptake in lymph nodes of both patients with active SLE and patients with inactive SLE suggests that metabolic, and probably immunologic, activity is enhanced not only in active, but also in clinically quiescent, disease. The increased thymic uptake observed only in patients with active disease suggests that the thymus plays an important role during periods of disease activity.

Cellular and humoral immune parameters in women with pathological hyperprolactinemia before and during treatment with bromocriptine

PROBLEM

Experimental and clinical evidence has suggested an immunostimulatory effect of prolactin and that bromocriptine, an inhibitor of prolactin release, counteracts the actions of prolactin on the immune system. The aim of this study was to determine the impact of elevated serum prolactin levels on the immune system in patients with pathological hyperprolactinemia.

METHOD

For this purpose, parameters of the cellular and humoral immune system were studied in six women with prolactinomas and one with idiopathic hyperprolactinemia. Studies were performed when serum prolactin concentrations were high as well as during different phases of the menstrual cycle when prolactin levels had been normalized through treatment with bromocriptine.

RESULTS

Hyperprolactinemic subjects, when compared with six age-matched normal women, had significantly higher percentages of total lymphocytes and CD2+ cells. Elevation of CD4+ cells was also observed although to a lesser extent. Bromocriptine-treated patients, when compared with normal women were characterized by increased numbers of total lymphocytes and CD4+ cells, decreased percentage of CD8+ cells, and increased concentrations of serum IgM. These last two findings were also significantly different when compared to those observed in hyperprolactinemia.

CONCLUSION

In this study we have described the changes on cellular and immune parameters in patients with hyperprolactinemia before and during bromocriptine therapy, which support the links of communications between the immune and endocrine systems in humans.

Key data elements for use in cost-utility modeling of biological treatments for rheumatoid arthritis

OBJECTIVES

Economic evaluation is becoming more common and important as new biologic therapies for rheumatoid arthritis (RA) are developed. While much has been published about how to design cost-utility models for RA to conduct these evaluations, less has been written about the sources of data populating those models. The goal is to review the literature and to provide recommendations for future data collection efforts.

METHODS

This study reviewed RA cost-utility models published between January 2006 and February 2014 focusing on five key sources of data (health-related quality-of-life and utility, clinical outcomes, disease progression, course of treatment, and healthcare resource use and costs). It provided recommendations for collecting the appropriate data during clinical and other studies to support modeling of biologic treatments for RA.

RESULTS

Twenty-four publications met the selection criteria. Almost all used two steps to convert clinical outcomes data to utilities rather than more direct methods; most did not use clinical outcomes measures that captured absolute levels of disease activity and physical functioning; one-third of them, in contrast with clinical reality, assumed zero disease progression for biologic-treated patients; little more than half evaluated courses of treatment reflecting guideline-based or actual clinical care; and healthcare resource use and cost data were often incomplete.

CONCLUSIONS

Based on these findings, it is recommended that future studies collect clinical outcomes and health-related quality-of-life data using appropriate instruments that can convert directly to utilities; collect data on actual disease progression; be designed to capture real-world courses of treatment; and collect detailed data on a wide range of healthcare resources and costs.

Familial occurrence of big-big prolactin as the predominant immunoreactive human prolactin species in blood

The occurrence of big-big prolactin (PRL) as the major form of circulating immunoactive PRL has been described in ovulatory hyperprolactinemia. In this study, we have analyzed the heterogeneity of circulating human PRL in 17 members of three families in which one member, bearing galactorrhea-hyperprolactinemic syndrome, was known to have serum big-big PRL as the predominant circulating species. Gel filtration patterns of serum samples of all subjects revealed the presence of significant proportions of big-big PRL in more than one member of the same family, thus suggesting the familial occurrence of big-big as the predominant immunoreactive PRL species in blood.

Visceral larva migrans mimicking rheumatic diseases

OBJECTIVE

To report rheumatologic or rheumatologic-like manifestations of the visceral larva migrans (VLM) syndrome.

METHODS

We carried out a prospective study of patients with VLM seen in a private practice setting in Mexico City between 1990 and 1993.

RESULTS

From a population of 600 patients we identified 6 patients (5 women) with VLM. Three patients complained of arthralgia; in 4 a history of migratory cutaneous lesions was elicited, and in one monoarthritis of the right knee was found. One patient had deep edema that suggested thrombophlebitis of the right arm; the man in our series had right testicular swelling during followup. In 2 cases, panniculitis was documented by biopsy and in one, small vessel vasculitis. Four patients had frequent contact with dogs and one with cats; 4 patients frequently ate raw fish. The diagnosis of VLM was confirmed either by the clinical picture, biopsy, or ELISA:

CONCLUSION

The spectrum of rheumatological manifestations in VLM may be wider than previously thought.

Reduced dopaminergic inhibition of thyrotropin release in hyperprolactinemic ovulatory women

It has been suggested that menstrual irregularities in hyperprolactinemia are secondary to an increase in hypothalamic dopaminergic activity via a short loop positive feedback of prolactin (PRL). We have studied this question in a relatively new syndrome characterized by hyperprolactinemia without derangements of the hypothalamic-pituitary-ovarian function due to macroprolactinemia (abnormal high amounts of big-big PRL). Central dopaminergic activity was investigated by the administration of the dopamine antagonist domperidone to normal women (n = 7) and women with anovulatory (n = 6) and ovulatory hyperprolactinemia (n = 2). The effects of domperidone were evaluated in all subjects by the measurements of radioimmunoassayable circulating serum PRL and TSH levels. All subjects had a significant increase in serum PRL levels after 90 min of domperidone administration. Anovulatory hyperprolactinemic subjects showed the highest response to domperidone in terms of TSH, whereas normal women and women with ovulatory hyperprolactinemia had similar increments in TSH serum levels after the administration of the dopamine antagonist. These results support the observation that an increase of hypothalamic dopaminergic activity in hyperprolactinemia may account in part for the presence of menstrual irregularities. The presence of a similar pituitary responsiveness in terms of TSH to domperidone in normal and ovulatory hyperprolactinemic women suggests a similar hypothalamic dopaminergic activity in both group of subjects. These findings might offer an explanation for the coexistence of normal ovulatory cycles in spite of hyperprolactinemia.

Peripheral blood lymphocyte subsets and serum immunoglobulins in Sheehan's syndrome and in normal women during the menstrual cycle

OBJECTIVE

There has been increasing evidence on the mechanisms underlying the interactions between the neuroendocrine and the immune systems, particularly in animal models with relatively few information in the human. In this study, we evaluate the cellular and humoral immunity in female patients with hypopituitarism and in normal women throughout the menstrual cycle in an attempt to determine the role of pituitary and gonadal hormones on the immune system.

DESIGN

Serum immunoglobulins, peripheral blood lymphocyte subsets, and serum hormones were measured in eight patients with postpartum pituitary necrosis (Sheehan's syndrome) and in six normal women along different phases of the menstrual cycle, taking advantage of the lack of pituitary function and the cyclic variations in serum hormones, respectively.

RESULTS

Patients with Sheehan's syndrome had higher T lymphocytes (CD2), including helper (CD4) and suppressor (CD8) cell subpopulations and B lymphocytes (CD19) when compared with normal menstruating women. An increase of serum IgA concentrations was also observed. Normal women showed little non-statistically different changes along the menstrual cycle in peripheral blood cell parameters and in serum immunoglobulin levels.

CONCLUSIONS

a) Hypopituitarism in humans, in contrast with the animal model, may associate with immune up-regulation at both cellular and humoral levels; and b) hormonal changes along the normal menstrual cycle probably do not influence in great extent the immune system.