Brain functional and structural changes in diabetic children. How can intellectual development be optimized in type 1 diabetes?

The neuropsychological functioning of people with type 1 diabetes (T1D) is of key importance to the effectiveness of the therapy, which, in its complexity, requires a great deal of knowledge, attention, and commitment. Intellectual limitations make it difficult to achieve the optimal metabolic balance, and a lack of this alignment can contribute to the further deterioration of cognitive functions. The aim of this study was to provide a narrative review of the current state of knowledge regarding the influence of diabetes on brain structure and functions during childhood and also to present possible actions to optimize intellectual development in children with T1D. Scopus, PubMed, and Web of Science databases were searched for relevant literature using selected keywords. The results were summarized using a narrative synthesis. Disturbances in glucose metabolism during childhood may have a lasting negative effect on the development of the brain and related cognitive functions. To optimize intellectual development in children with diabetes, it is essential to prevent disorders of the central nervous system by maintaining peri-normal glycemic levels. Based on the performed literature review, it seems necessary to take additional actions, including repeated neuropsychological evaluation with early detection of any cognitive dysfunctions, followed by the development of individual management strategies and the training of appropriate skills, together with complex, multidirectional environmental support.

POS0316 MODELLING SHORT-TERM FVC CHANGES FROM SENSCIS TO LONG-TERM FVC COURSE IN SSc-ILD DEMONSTRATES CLINICALLY MEANINGFUL REDUCTION OF FVC DECLINE AND SURVIVAL BENEFITS

Background:

Nintedanib has shown to slow FVC decline by 41ml over 52 weeks in systemic sclerosis-associated interstitial lung disease (SSc-ILD). However, the long-term effect of nintedanib treatment on ILD progression and mortality in SSc patients is so far unknown.

Objectives:

Here, the 52-week treatment efficacy of nintedanib was modeled and extrapolated on the long-term FVC course and survival in SSc-ILD patients from the European Scleroderma Trial and Research (EUSTAR) database.

Methods:

SSc patients from the EUSTAR database fulfilling the inclusion criteria of the SENSCIS trial (SSc classification criteria, ILD confirmed by imaging, disease duration of <7 years, FVC≥40%pred, diffusion capacity of the lung for carbon monoxide (DLCO) 30-89%pred); and matched for baseline characteristics as well as matched for the 52-week FVC change of SENSCIS patients were included (n=236). Linear mixed models including time, risk factors at baseline (sex, age, dyspnea class, DLCO%, CRP, modified Rodnan skin score, SSc subtype, SSc auto-antibodies, disease duration, synovitis and muscle weakness) were used to estimate the natural FVC course over time. On this natural course of FVC, the observed effect from the SENSCIS trial representing the absolute 52-week difference of FVC decline between the nintedanib and the placebo group was applied as continuous annual effect (SENSCIS effect model). Survival was estimated for both the natural course as well as the SENSCIS effect model using Cox regression.

Results:

Of the 236 included patients, 75% were females, 65% had diffuse cutaneous SSc. Mean age was 50.6 years, mean FVC 78.2%pred and DLCO 56.3%pred at time of inclusion. Mean FVC change after 12±3 months was -2.3 ±6.9%pred. These parameters were largely similar to the characteristics of the SENSCIS population.

In the longitudinal follow up of this population, the natural course of FVC showed a total FVC decline of -16.3%pred over 5 years. With assumed SENSCIS effects (effects of nintedanib treatment reported in SENSCIS), the 5-year FVC decline was reduced to -10.3%pred (Figure 1).

The reduced FVC progression translated into an improved survival. The natural 5-year survival of this SSc-ILD population was 88.2%. When extrapolating also a severe FVC decline early in the course, frequently terminated by early mortality of SSc patients excluding them from long-term outcome assessment, the estimated 5-year survival was reduced to 81.6%. When the SENSCIS effects on FVC were considered, the 5-year extrapolated survival was increased to 86.3% (Figure 2).

Conclusion:

Long-term experience of nintedanib treatment in SSc-ILD patients is lacking so far, therefore we modeled and extrapolated the 52-week treatment efficacy of nintedanib on the long-term FVC course and survival in SSc-ILD patients from the EUSTAR database. We could demonstrate a significant reduction of FVC decline by extrapolating the annual treatment effects of nintedanib from the SENSCIS trial from 1 to 5 years in EUSTAR. Translating these reductions of FVC decline into survival, the 5-year mortality rate was reduced from 18% to 13%.

Disclosure of Interests:

Anna-Maria Hoffmann-Vold Speakers bureau: Boehringer Ingelheim, Actelion, Roche, Merck Sharp & Dohme, Lilly, Consultant of: Actelion, Boehringer Ingelheim, Roche, Bayer, Merck Sharp & Dohme, ARXX, Lilly and Medscape, Grant/research support from: Boehringer Ingelheim, Dörte Huscher: None declared, Paolo Airò Speakers bureau: Boehringer Ingelheim, Consultant of: Bristol-Myers-Squibb, Novartis, Elisabetta Zanatta Speakers bureau: Boehringer Ingelheim, Actelion, GSK, Paid instructor for: GSK, Consultant of: Boehringer Ingelheim, GSK, Patricia Carreira Speakers bureau: Actelion, Boehringer Ingellheim, Janssen, GSK, Paid instructor for: Boehringer Ingelheim, Consultant of: AbbVie, Boehringer Ingelheim, VivaCell, Emerald Health Pharmaceuticals, Gesynta Pharma, Sanofi Genzyme, Grant/research support from: Roche, GSK, Yannick Allanore Consultant of: Honorarium received from Boehringer, Medsenic

Sanofi, Menarini, Grant/research support from: Grants received from Alpine, Ose Immunogenetics, Ulf Müller-Ladner Speakers bureau: Boehringer Ingelheim, Consultant of: Boehringer Ingelheim, Alessandro Giollo: None declared, Maria Rosa Pozzi: None declared, CAROLINA SOUZA MULLER Speakers bureau: Boehinger Ingelheim, Janssen, Roche, LIBBS, Bristol-Myers-Squib, Radim Bečvář Consultant of: Actelion, Boehringer Ingelheim, Michele Iudici: None declared, Dominik Majewski Speakers bureau: Boehringer Ingelheim - 2 x paid as a speaker, Armando Gabrielli Grant/research support from: Pfizer, CSL Behring, Margarida Alves Employee of: Boehringer Ingelheim, Nils Schoof Employee of: Boehringer Ingelheim International GmbH, Oliver Distler Speakers bureau: Boehringer Ingelheim, Medscape, IQone, Roche, Consultant of: Abbvie, Acceleron Pharma, Amgen, AnaMar, Arxx Therapeutics, Baecon Discovery, Blade Therapeutics, Bayer, Boehringer Ingelheim, ChemomAb, Corbus Pharmaceuticals, CSL Behring, Galapagos NV, Glenmark Pharmaceuticals, GSK, Horizon (Curzion) Pharmaceuticals, Inventiva, iQvia, Italfarmaco, Kymera Therapeutics, Lilly, Medac, Mitsubishi Tanabe Pharma, MSD, Novartis, Pfizer, Roche, Sanofi, Serodapharm, Topadur, Target Bioscience and UCB, Grant/research support from: Kymera Therapeutics, Mitsubishi Tanabe

Chloroquine and hydroxychloroquine - safety profile of potential COVID-19 drugs from the rheumatologist's perspective

INTRODUCTION AND OBJECTIVE

The COVID-19 pandemic causes vital concerns due to the lack of proved, effective, and safe therapy. Chloroquine and hydroxychloroquine seem to be useful, but recently serious concerns regarding their adverse events have risen. The aim of the study was to broaden the general perspective of chloroquine and hydroxychloroquine use in COVID-19 treatment, based on an analysis of their current safety profile among patients with rheumatic diseases.

MATERIAL AND METHODS

The study was based on a group of 152 patients with rheumatic diseases, aged 20-78 years, treated either with chloroquine or hydroxychloroquine. Analyzed data included age, gender, comorbidities, type of drug, dosage, treatment duration, and reported adverse events. Cases of drug withdrawal related to adverse events were also recorded.

RESULTS

The dosage was consistent in both groups: 250 mg of chloroquine or 200 mg of hydroxychloroquine daily. 77.6% of patients did not experience any adverse reactions to the treatment. Hydroxychloroquine showed better safety profile, with 10.9% of patients reporting side-ffects, compared to 28.9% in patients treated with chloroquine. The overall incidence of ophthalmic complications was 6.6%. For both drugs, no statistically significant correlation between adverse events and age, chronic heart or liver disease, or hypertension was found.

CONCLUSIONS

Chloroquine and hydroxychloroquine at lower doses, as used in rheumatic diseases, prove to be relatively safe. Data from the literature show that high dosage as recommended in COVID-19 treatment may pose a risk of toxicity and require precise management, but prophylactic, long-term use of lower, safe doses might be a promising solution.

Th17/Treg-Related Transcriptional Factor Expression and Cytokine Profile in Patients With Rheumatoid Arthritis

Objectives

The aim of our study was to determine whether there is a correlation between transcription factors expression and Th17/Treg ratio, cytokine profile in the RA phenotype as well as to identify transcription factors that could be a potential biomarker for RA.

Methods

The study was conducted on 45 patients with RA, 27 patients with OA and 46 healthy controls (HCs). Th17 and Treg frequency was determined by flow cytometry (15 patients with RA/OA and 15 subjects of HC). Gene expression was estimated by qPCR, and the serum cytokine levels were determined by ELISA.

Results

The percentage of Treg (CD4+CD25highCD127-) cells in RA patients was lower than in OA patients or HCs. Proportions of Th17 (CD4+CCR6+CXCR3-) cells were higher in RA and OA in comparison to HCs. STAT5 showed a very high expression in the blood of RA patients compared to healthy subjects. The expression of STAT5 and HELIOS was not detected in Th17 cells. A positive correlation between SMAD3 and STAT3 in RA patients was observed. Negative correlations between HIF-1A and SMAD2 in RA Treg cells and DAS-28 score were observed. The range of serum of IL-17 and IL-21 were higher in RA patients than in OA patients. Concentrations of serum IL-2 and IFN-γ were higher in RA and OA patients than in healthy subjects. Based on the ROC analysis, the diagnostic potential of the combination of HIF1A, SMAD3 and STAT3, was determined at AUC 0.95 for distinguishing RA patients from HCs. For distinguishing RA patients from OA patients the diagnostic potential of the combination of SMAD2, SMAD3, SMAD4 and STAT3, was determined at AUC 0.95.

Conclusion

Based on our study, we conclude that SMAD3 and STAT3 could be potential diagnostic biomarkers for RA.

The Role of MECP2 and CCR5 Polymorphisms on the Development and Course of Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic and systemic autoimmune disease. SLE is described by production of autoantibodies and causes damage of many organs. T-cells play a crucial role in SLE pathogenesis. T-cells intensify inflammation through a number of processes, which leads to autoimmunization. CCR5 and MECP2 genes are linked with T-cells and pathogenesis of SLE. Polymorphisms in these genes are related with the prognostic factors of risk of disease onset and disease severity. The aim of this study was to estimate the influence of polymorphisms in MECP2 and CCR5 genes on the development and course of systemic lupus erythematosus. We examined 137 SLE patients and 604 healthy controls. We studied polymorphisms for CCR5 gene: rs333 and for MECP2: rs2075596, rs1734787, rs17435, and rs2239464. We genotyped our MECP2 samples and we performed a restriction fragment length polymorphism (RFLP) analysis for CCR5 samples. We showed a risk factor for allele T in rs17435 and for allele A in rs2075596 in MECP2. We noticed that MECP2 rs2075596 G/A, rs1734787 C/A, rs17435 A/T, and rs2239464 G/A polymorphisms are more prevalent in SLE patients than in healthy controls. We believe that above-mentioned MECP2 polymorphisms can be considered as SLE susceptibility factor.

IL-6 and TGF-β gene polymorphisms, their serum levels, as well as HLA profile, in patients with systemic lupus erythematosus

OBJECTIVES

The aim of the study was to explore whether TGF-β and IL-6 gene polymorphisms may be associated with SLE and assess the frequency of HLA-DRB1 alleles in Polish systemic lupus erythematosus (SLE) patients.

METHODS

216 SLE patients and 552 healthy individuals were examined for TGF-β rs1800469 and rs1800470 by TaqMan SNP genotyping assay and for and IL-6(rs2069827 and rs1800795 using the PCR- RFLP method.

RESULTS

An increased frequency of TT genotype and T allele of the TGF β -509 C/T was found in SLE patients (p=0.02). The TGF-β 869 C allele was more frequent in SLE patients. The genotype-phenotype analysis showed association between the TGF β -509 C/T and mean value of CRP, ESR, haemoglobin, APTT, Pt and INR (p=0.05, p=0.03, p<0.001, p=0.03, p=0.03 and p=0.05, respectively) as well as anti-SSA and anti-Sm presence (p=0.04 and p=0.03, respectively); the TGF- β 869 T/C and mean value of APTT and INR (p=0.01 and p=0.05, respectively); the IL-6 -174 G/C and SLICC (p=0.05), anti-SSA (p=0.05) and anti-SSB (p=0.05). A higher TGF-β and IL-6 serum level were found in SLE patients compared to controls (both p<0.0001). In SLE patients with the TGF-β -509 TT genotype have shown positive association with the TGF-β serum levels. Polish SLE patients have strong positive association with HLA-DRB1*52.1, and negative with the HLA-DRB1*07:01 allele. HLA-DRB1*52.1 was also associated with higher TGF-β serum levels in the Polish population.

CONCLUSIONS

Our results suggested that the TGF β -509 C/T variant may be considered as a genetic marker for SLE in the Polish population.

Immunodeficiency and autoimmunity during biological disease-modifying antirheumatic drug therapy

Biological disease-modifying antirheumatic drugs target specific components of the immune response related to pathogenesis of autoimmune and inflammatory diseases. Introduction of biologic therapies has enabled better disease control than conventional drugs and thus a reduction in comorbidity and mortality. However, there is concern about adverse effects of these drugs including infections, cancers and drug-induced autoimmune diseases. Patients undergoing biologic treatment are at small but significant risk of serious infections. The overall risk of malignancies in patients on biologics compared with the general population is not increased, but there is evidence of a higher risk of individual cancers. Surprisingly, biological treatment may induce autoantibody production and, rarely, development of autoimmune diseases. A growing body of literature has evaluated the risk of adverse effects during biologic therapies. This paper outlines adverse effects of biological disease-modifying antirheumatic drugs related to immune system disorders, both immunodeficiency and autoimmunity.

Subcortical gray matter atrophy is associated with cognitive deficit in multiple sclerosis but not in systemic lupus erythematosus patients

Cognitive impairment is a significant clinical problem both in multiple sclerosis (MS) and systemic lupus erythematosus (SLE) patients. In MS cognitive dysfunction has been associated with brain atrophy and total demyelinating lesion volume. In SLE cognitive impairment is much less understood, and its link to structural brain damage remains to be established. The aim of this study was to identify the relationship between subcortical gray matter volume and cognitive impairment in MS and SLE. We recruited 37 MS and 38 SLE patients matched by age, disease duration and educational level. Patients underwent magnetic resonance imaging (MRI) and a battery of psychometric tests. Severity of cognitive impairment was similar in both cohorts despite larger white matter lesion load in MS patients. Psychometric scores were associated with global and subcortical gray matter atrophy measures and lesion load in MS, but not in SLE. In SLE, the lack of a relationship between cognitive impairment and structural damage, defined either as atrophy or white matter lesions, indicates a different causal mechanism of cognitive deficit.

Decreased mRNA expression levels of DNA methyltransferases type 1 and 3A in systemic lupus erythematosus

OBJECTIVES

Systemic lupus erythematosus (SLE) is a chronic relapsing autoimmune disease characterized by the presence of autoantibodies directed against nuclear antigens and by chronic inflammation. Although the etiology of SLE remains unclear, the influence of environment factors, which is largely reflected by the epigenetic mechanisms, with DNA methylation changes in particular, is generally considered as main players in the pathogenesis of SLE. We studied DNA methyltransferases' (DNMTs) type 1, 3A and 3B transcript levels in peripheral blood mononuclear cells from patients diagnosed with systemic lupus erythematosus and from the healthy control subjects. Furthermore, the association of DNMT1, DNMT3A, and DNMT3B mRNA levels with gender, age, and major clinical manifestations was analyzed.

METHODS

Peripheral blood mononuclear cells (PBMCs) were isolated from 32 SLE patients and 40 healthy controls. Reverse transcription and real-time quantitative polymerase chain reaction (RT-qPCR) analyses were used to determine DNMT1, DNMT3A, and DNMT3B mRNA expression levels.

RESULTS

Significantly lower DNMT1 (p = 0.015543) and DNMT3A (p = 0.003652) transcript levels in SLE patients were observed compared with healthy controls. Nevertheless, the DNMT3B mRNA expression levels were markedly lower compared with DNMT1 and DNMT3A, both in PBMCs from affected patients and those from control subjects. Furthermore, the DNMT1 transcript levels were positively correlated with SLE disease activity index (SLEDAI) (r s = 0.4087, p = 0.020224), while the DNMT3A transcript levels were negatively correlated with patients age (r s = -0.3765, p = 0.03369).

CONCLUSIONS

Our analyses confirmed the importance of epigenetic alterations in SLE etiology. Moreover, our results suggest that the presence of some clinical manifestations, such as phototosensitivity and arthritis, might be associated with the dysregulation of DNA methyltransferases' mRNA expression levels.

Serum resistin concentrations in children with type 1 diabetes mellitus--negative relation to body fat mass

INTRODUCTION

Insulin is one of the major factors regulating adipose tissue function. On the other hand, adipocytes secrete adipocytokines that may influence insulin synthesis and action, and are involved in blood glucose regulation. In type 1 diabetes mellitus (t1DM), beta cells function is replaced with exogenous insulin therapy. This raises a question concerning the impact of t1DM on adipose tissue secretory function. The aim of this study was to evaluate one of the adipocytokines, resistin, serum concentrations in relation to body fat mass in children with t1DM.

MATERIAL AND METHODS

The study comprised 75 children with t1DM and a control group of 20 healthy coevals. All children had estimated serum resistin concentrations, glycated haemoglobin levels, growth and body weight measurements, and bioelectrical impedance analysis in order to establish body composition.

RESULTS

Resistin serum concentrations were significantly lower in children with t1DM vs. controls (median values: 343 vs. 590 pg/mL; mean values ± SD: 577 ± 561 vs. 861 ± 628 pg/mL; p < 0.001), and they negatively correlated with body fat mass (p = 0.022) and age (p = 0.022) in the t1DM group, but not in the control group. Disease duration, glycated haemoglobin levels and insulin dosage revealed no direct statistical relation to resistin levels.

CONCLUSIONS

Diminished serum resistin concentrations and a negative correlation between resistin levels and body fat mass in children with type 1 diabetes seem to result from broken physiological adipo-insular regulations, independent of disease duration, its metabolic control and insulin supply.

Serum leptin and adiponectin levels in children with type 1 diabetes mellitus - Relation to body fat mass and disease course

PURPOSE

Leptin and adiponectin are adipokines presenting a wide range of impacts, including glycemic balance regulations. Insulin is one of the main regulators of adipose tissue function. In type 1 diabetes mellitus (T1DM) endogenous insulin secretion is replaced by the exogenous supply, which is not regulated naturally. The aim of the study was to establish serum leptin and adiponectin levels, and their relations to body fat mass and disease course in children with T1DM.

MATERIAL/METHODS

The study included 75 children with T1DM and the control group of 20 healthy coevals. All children had estimated serum leptin and adiponectin concentrations, lipid profile, and bioelectrical impedance analysis.

RESULTS

Serum leptin concentrations in children with T1DM were not significantly different from the control group (p=0.067, mean values±SD: 3.11±2.98 vs. 5.29±5.06μg/l, respectively), and related positively to body fat mass in both groups. Adiponectin serum concentrations were significantly higher in children with T1DM than in the control group (p<0.001; mean values: 18.82±9.31 vs. 12.10±5.53μg/ml, respectively), and were not related to the body fat content in the study group. Both, leptin and adiponectin, showed no relation to any of the analyzed parameters of the disease course.

CONCLUSIONS

Differences observed between children with T1DM and their healthy coevals, when similar in terms of age, body weight, and body fat mass, seem not to depend directly on the disease duration, its metabolic control or insulin supply.

[Differential diagnosis of polymyositis. Case report]

INTRODUCTION

Polymyositis is a connective tissue disease of unknown etiology. Autoimmune processes in genetically predisposed individuals play an important role in the pathogenesis of this disease. It is suspected that environmental factors operate in the initiation of the autoimmune response. The differential diagnosis of polymyositis should take into consideration various disorders presenting with muscular lesions or weakness.

CASE REPORTS

Our 33-year-old female was referred in 2010 to the Department of Rheumatology, Rehabilitation, and Internal Medicine, Poznań University of Medical Sciences, with suspected polymyositis. She reported symptoms of upper airway infection in December 2009 with muscle tenderness in the pelvic and pectoral girdles and the dorsum. An antibiotic was administered but aggravation of symptoms was noted instead. She was hospitalized with muscle weakness and elevated CPK (16300 U/L), LDH (2322 IU/L), aminotransferases, ESR, and CRP. Other causes of muscular lesions or weakness were ruled out. Polymyositis was tentatively diagnosed by a rheumatologist and the patient was started on non-steroid anti-inflammatory agents. After one week in hospital, improvement in the general condition and normalization of laboratory tests were noted (CPK and LDH activities declined). The patient was referred to our Department for further investigation and treatment. Basing on the anamnesis, physical examination, and laboratory findings, and taking into consideration that the patient quickly improved and the tests normalized without glucocorticoids, we decided against the diagnosis of polymyositis.

CONCLUSIONS

Our differential diagnosis attributed the symptoms of inflammatory muscle disease to an infectious or chemical factor or to a malignancy as the primary condition.

[Fibrodysplasia ossificans progressiva: case report]

Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disease characterized by widespread soft tissue ossification and congenital stigmata of the extremities. We report the case of a 33-year-old woman with clinical and radiological features of FOP. She was born with bilateral hallux valgus and at the age of 10 presented swelling and ossification of the left scapula. During the course of the disease numerous crises were observed. In this patient authors noticed FOP exacerbation after a surgical operation.

[Polymyositis and systemic sclerosis symptoms as a clinical manifestation of a chronic graft versus host disease: a case report and literature review]

A case of a patient presenting with polymyositis and systemic sclerosis symptoms due to chronic graft versus host disease is reported. The literature review about similar disease manifestations and hypotheses regarding the pathophysiological origin of the clinical syndromes combined with graft versus host reaction is presented.

[Ocular involvement in patient with Wegener's granulomatosis--a case report]

Wegener's granulomatosis is a systemic vasculitis. Most often granulomatous inflammation is situated in upper and lower respiratory tracts as well as kidneys. Ocular involvement affects 50-60% of patients with Wegener's granulomatosis. Herein is reported the case of a man with Wegener's granulomatosis with ocular involvement which was a symptom of high disease activity. Intensive immunosuppressive treatment and local treatment were ineffective in eye involvement inhibition.

[Diagnostic difficulties in polymyositis]

Polymyositis is a connective tissue disease. Although myositis is the dominant clinical manifestation, internal organs may also be affected. Arthritis occurs in 30% of patients, especially in the course of the anti-synthetase syndrome. We report on a case of a woman with polymyositis and interstitial lung disease. Arthritis and the presence of anti-cyclic citrullinated peptide antibodies in the patient's serum may suggest the diagnosis of the overlap syndrome.

[Coincidence of juvenile idiopathic arthritis and multiple sclerosis: case report]

INTRODUCTION

Juvenile idiopathic arthritis is a systemic pathology of connective tissue characterized by a chronic inflammatory process with an autoimmune background whereas multiple sclerosis is a demyelination disease with an important role of immune disorders in its pathogenesis. The etiology in both cases remains unknown. The coincidence of juvenile idiopathic arthritis and multiple sclerosis was described a just a few patients.

MATERIAL AND METHODS

We now report on a 31-year-old woman with juvenile idiopathic arthritis and multiple sclerosis. In the present case, the main problem was to find the right proper medication for a very, aggressive course of multiple sclerosis and for arthritis.

RESULT

Treatment with interferon-beta and methylprednisolone led to remission with just minor side-effects.

[Graft-versus-host disease as the cause of symptoms mimicking Sjögren's syndrome]

A case of chronic graft-versus-host disease (chronic GvHD) mimicking symptoms associated with idiopathic Sjögren's syndrome is presented. Hypotheses on the pathophysiological origin of clinical syndromes associated with graft-versus-host disease are discussed.

Graft-facilitating doses of ex vivo activated gammadelta T cells do not cause lethal murine graft-vs.-host disease

The purpose of this study was to examine the ability of gamma(delta) T cells to cause graft-vs.-host disease (GVHD) after allogeneic bone marrow transplantation (BMT) and to determine whether these cells offered any therapeutic advantages relative to alphabeta T cells. Due to the paucity of naive gamma(delta) T cells in mice and humans, gamma(delta), T cells (obtained from alpha(beta) T cell-deficient murine donors) were ex vivo activated and expanded in interleukin (IL)-2 so as to achieve sufficient cell numbers and to serve as a more clinically feasible strategy. After transplantation into lethally irradiated hosts, donor gamma(delta) T cells were detected in target organs of GVHD such as the spleen and intestines 2 weeks after BMT and constituted the primary T cell subpopulation. Large doses (150 x 10(6)) of activated gamma(delta) T cells, which we have previously shown capable of facilitating engraftment in MHC-disparate recipients, failed to cause fatal GVHD in lethally irradiated recipients of MHC-incompatible donor marrow grafts (C57BL/6 [H-2b]-->B10.BR [H-2k] and C57BL/6 [H-2b]-B6D2F1[H-2b/d]). The absence of GVHD was confirmed by histologic analysis of target organs, splenic B cell reconstitution, and appropriate negative selection in the thymus, that were all comparable to those observed in mice transplanted with T cell-depleted BM only. While early splenic reconstitution was attributable to donor gamma(delta) T cells, analysis of durably engrafted chimeras 2 months posttransplant revealed that the vast majority of donor splenic T cells expressed the alpha(beta) T cell receptor. The results of secondary adoptive transfer assays showed that these cells were tolerant of recipient alloantigens in vivo, demonstrating that gamma(delta) T cells did not prevent the subsequent development of donor anti-host tolerance in BM-derived alpha(beta) T cells. When comparatively evaluated, the minimal number of naive alpha(beta) T cells necessary for donor engraftment caused significantly more fatal GVHD than the corresponding minimal dose of activated gamma(delta) T cells and thus had a superior therapeutic index. These studies indicate that doses of activated gamma(delta) T cells that are able to promote alloengraftment do not cause lethal GVHD in mice transplanted with MHC-incompatible marrow grafts.

Ex vivo anti-CD3 antibody-activated donor T cells have a reduced ability to cause lethal murine graft-versus-host disease but retain their ability to facilitate alloengraftment

The purpose of this study was to determine whether ex vivo anti-CD3 Ab-activated T cells behaved in a biologically similar manner as naive T cells with respect to causing graft-vs-host disease (GVHD) and facilitating engraftment after allogeneic marrow transplantation. This question was addressed using two well-defined MHC-incompatible murine models of GVHD (C57BL/6 (H-2b)-->BIO.BR (H-2k)) and engraftment (C57BL/6 (H-2b)-->AKR/J (H-2k)). Transplantation with anti-CD3-activated T cells significantly reduced GVHD compared with that in animals transplanted with equivalent numbers of naive T cells. Protection from GVHD was not T cell subset dependent, as highly enriched populations of either activated CD4+ or CD8+ T cells caused less lethal GVHD than comparable numbers of purified naive CD4+ or CD8+ T cells. Transplantation with activated T cells also resulted in protection from LPS-mediated GVH lethality in unirradiated F1 recipients. Analysis of immune recovery indicated that animals transplanted with activated T cells had thymic and splenic B cell reconstitution that compared favorably to that in non-GVHD control mice. When engraftment was analyzed, equivalent degrees of donor cell engraftment were observed when animals were transplanted with limiting numbers (5 x 10(5)) of naive vs activated B6 T cells. Further studies indicated that activated CD8+ T cells were exclusively responsible for enhancing engraftment and that facilitation of engraftment was dependent upon the direct recognition of host MHC alloantigens. Collectively, these data demonstrate that transplantation with anti-CD3 Ab-activated T cells results in a reduction in GVHD, but these cells retain their ability to facilitate alloengraftment. The use of this approach in allogeneic marrow transplantation may represent an alternative strategy to mitigate GVHD without compromising engraftment.

Donor gamma delta T lymphocytes promote allogeneic engraftment across the major histocompatibility barrier in mice

T cells that express the alpha beta T-cell receptor are thought to be the T-cell population primarily responsible for facilitating alloengraftment. The role of gamma delta + T cells that comprise only a minority of mature T cells in promoting allogeneic engraftment, however, has not been extensively studied. The purpose of this study was to determine whether gamma delta T cells were capable of facilitating alloengraftment in murine recipients of major histocompatibility complex-mismatched marrow grafts. We developed a model where engraftment of C57BL/6 x 129/F2(H-2b) marrow in sublethally irradiated (800 cGy) recipients (AKR/J, H-2k) is dependent on the presence of mature donor T cells in the marrow graft. In this model, donor T-cell engraftment was significantly augmented by as few as 1 x 10(5) alpha beta T cells. The role of gamma delta T cells was then investigated using transgenic donors (C57BL/6 x 129 background) in which a portion of the T-cell receptor-beta chain gene was deleted by gene targeting so that these mice lack alpha beta T cells. Addition of 10 x 10(5) naive gamma delta T cells to T-cell depleted marrow grafts was required to significantly increase alloengraftment, although donor T cells averaged < 50% of total splenic T cells. To determine whether higher doses of gamma delta T cells would improve donor engraftment and eradicate residual host T cells, gamma delta T cells were ex vivo expanded with a gamma delta T-cell-specific mono-clonal antibody and interleukin-2 and then transplanted into irradiated recipients. Transplantation of > or = 160 x 10(6) activated gamma delta T cells was necessary to consistently and significantly augment donor cell chimerism and enhance hematopoietic reconstitution when compared to control mice, but host T cells persisted in these chimeras. Addition of 2.5 x 10(4) mature alpha beta T cells, which alone were incapable of facilitating engraftment, to T-cell depleted marrow grafts containing 160 x 10(6) activated gamma delta T cells resulted in long-term (> 100 day) complete donor engraftment, indicating that limiting numbers of alpha beta T cells were required in the marrow graft for the eradication of residual host T cells. Using serial weight curves and B-cell reconstitution as end points, clinically significant graft-versus-host disease was not observed in these chimeras under these experimental conditions. These data show that, whereas less potent than alpha beta T cells, gamma delta T cells are able to promote engraftment and enhance hematopoietic reconstitution in allogeneic marrow transplant recipients.

Modulation of in vitro and in vivo T-cell responses by transferrin-gallium and gallium nitrate

Gallium is a group IIIa metal that has efficacy in the therapy of malignant disorders such as lymphoma and urothelial tract tumors. Preclinical studies also indicate a role for gallium in autoimmune disorders, suggesting that gallium is able to modulate T-cell immune reactivity. The purpose of this study was to examine the in vitro and in vivo immunomodulatory action of gallium on T-cell function. Since gallium binds to transferrin in vivo, in vitro studies evaluated the effect of transferrin-gallium (Tf-Ga) on human T cells. Tf-Ga inhibited the mitogen-induced proliferative response of peripheral blood mononuclear cells (PBMC) in a dose-dependent fashion. Alloantigen-induced proliferation was also potently suppressed when evaluated in a mixed lymphocyte culture assay. Tf-Ga affected a significant reduction in the density of IL-2 receptors on activated T cells and a slight reduction in the number of CD3+/CD25+ T cells in PHA-stimulated cultures. Neither secretion of interleukin-2 (IL-2) nor the induction of IL-2-stimulated lymphokine-activated killer activity, however, was inhibited by Tf-Ga. Tf-Ga produced significant upregulation of the transferrin receptor (CD71) in T cells as determined by flow cytometric analysis and northern blot assay, but did not affect the percentage of CD3+/ CD71+ T cells after mitogen stimulation. To assess the in vivo effects of gallium on alloreactive T cells, we evaluated the immunosuppressive effect of gallium in a murine model of graft-versus-host disease (GVHD). Administration of gallium significantly prolonged survival in mice undergoing severe GVHD, suggesting that gallium can ameliorate GVH reactivity. Collectively, these data demonstrate that, at clinically achievable concentrations, Tf-Ga potently inhibits T-cell activation and that this immunosuppressive property of gallium may be of adjunctive therapeutic value in the management of disorders characterized by the presence of autoreactive or alloreactive T-cell populations.

Treatment of donor mice with an alpha beta T-cell receptor monoclonal antibody induces prolonged T-cell nonresponsiveness and effectively prevents lethal graft-versus-host disease in murine recipients of major histocompatibility complex (MHC)-matched and MHC-mismatched donor marrow grafts

The purpose of this study was to determine whether the administration of high doses of an anti-T-cell receptor (TCR) monoclonal antibody (H57-597) to donor animals could induce a state of T-cell nonresponsiveness and prevent the development of graft-versus-host disease (GVHD) in murine recipients of major histocompatibility complex (MHC)-matched (B10.BR[H-2k] --> AKR/J[H-2k]) and mismatched (B10.BR[H-2k] --> DBA/2[H-2d]) marrow grafts. Transplantation of H57-597-treated B10.BR T cells into irradiated AKR or DBA mice resulted in protection from GVHD, which was otherwise lethal in transplanted recipients receiving untreated T cells. The administration of H57-597-treated T cells did not compromise alloengraftment in either strain combination and was found to accelerate donor T-cell reconstitution in recipients of MHC-matched marrow grafts. Optimal protection for GVHD was dependent on the duration of antibody exposure in donor mice. T cells from donor exposed to antibody for only 1 day caused lethal GVHD, whereas exposure for at least 4 days was necessary to abrogate graft-versus-host reactivity. The ability of antibody treatment to protect against the development of GVHD could not be ascribed to the antibody-induced production of Th2 cytokines, the induction of a T- or non-T-suppressor cell population, or the preferential depletion of CD4+ T cells by H57-597. Donor T cells exposed to H57-597 antibody were detectable in recipients for up to 5 weeks after transplantation, indicating that these cells were not eliminated in the host immediately after bone marrow transplantation and contributed to enhanced donor T-cell reconstitution. Moreover, in B10.BR --> DBA chimeras that did not have any clinical evidence of GVHD, potentially MIs-reactive donor-derived Vbeta6+ T cells were present in the spleens of recipients at comparable numbers to normal mice but appeared functionally nonresponsive in vivo. These data strongly suggested that protection from GVHD was due to the fact that antibody treatment resulted in a state of prolonged T-cell anergy that persisted despite the presence of potential costimulatory signals in the recipient. This observation is of potential clinical significance in that it shows that the prevention of GVHD can be accomplished without posttransplantation immunosuppression or the need for in vitro or in vivo T-cell depletion.

Prevalence of human herpesvirus 6 variant A and B infections in bone marrow transplant recipients as determined by polymerase chain reaction and sequence-specific oligonucleotide probe hybridization

An oligotyping methodology was devised by using the polymerase chain reaction and sequence-specific oligonucleotide probe hybridization in order to discriminate the A and B variants of human herpesvirus 6 (HHV-6). Comparative DNA sequence analysis of portions of the U1102 (variant A) and Z29 (variant B) genomes revealed polymorphic regions which allowed for the synthesis of variant-specific and consensus oligonucleotide probes. These probes were found to hybridize exclusively to their respective HHV-6 variants. This strategy was then further tested by evaluating 16 clinical isolates derived from patients undergoing bone marrow transplantation to determine the subtype prevalence of HHV-6 infection in these patients. All clinical isolates were documented to be of variant B, indicating that the majority of bone marrow transplantation patients may be preferentially infected with this HHV-6 subtype. This oligotyping strategy may be useful in defining the relative prevalence of HHV-6A and HHV-6B infections in patient populations potentially at risk for HHV-6 disease.