Monoclonal antibodies for the treatment of COVID-19 patients: An umbrella to overcome the storm?

The world is facing up the most considerable vaccination effort in history to end the Coronavirus disease 2019 (COVID-19) pandemic. Several monoclonal antibodies (mAbs) direct against the Receptor binding domain of the S protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) received an Emergency Use Authorization for outpatient management of mild to moderate manifestation from COVID-19. MAbs could prevent the transmission SARS-CoV-2 infection and protect individuals from progression to severe disease. Under the pressure of different treatment strategies, SARS-CoV-2 has been demonstrated to select for different sets of mutations named "variants" that could impair the effectiveness of mAbs by modifying target epitopes. We provide an overview of both completed and unpublished, or ongoing clinical trials of mAbs used and review state of art in order to describe clinical options, possible indications, and the place in therapy for these agents in the treatment of COVID-19 with a particular focus on anti-spike agents. Then, we reassume the current evidence on mutations of the SARS-CoV-2 that might confer resistance to neutralization by multiple mAbs.

Dexamethasone-Induced FKBP51 Expression in CD4+ T-Lymphocytes Is Uniquely Associated With Worse Asthma Control in Obese Children With Asthma

Introduction

There is evidence that obesity, a risk factor for asthma severity and morbidity, has a unique asthma phenotype which is less atopic and less responsive to inhaled corticosteroids (ICS). Peripheral blood mononuclear cells (PBMC) are important to the immunologic pathways of obese asthma and steroid resistance. However, the cellular source associated with steroid resistance has remained elusive. We compared the lymphocyte landscape among obese children with asthma to matched normal weight children with asthma and assessed relationship to asthma control.

Methods

High-dimensional flow cytometry of PBMC at baseline and after dexamethasone stimulation was performed to characterize lymphocyte subpopulations, T-lymphocyte polarization, proliferation (Ki-67+), and expression of the steroid-responsive protein FK506-binding protein 51 (FKBP51). T-lymphocyte populations were compared between obese and normal-weight participants, and an unbiased, unsupervised clustering analysis was performed. Differentially expressed clusters were compared with asthma control, adjusted for ICS and exhaled nitric oxide.

Results

In the obese population, there was an increased cluster of CD4+ T-lymphocytes expressing Ki-67 and FKBP51 at baseline and CD4+ T-lymphocytes expressing FKBP51 after dexamethasone stimulation. CD4+ Ki-67 and FKBP51 expression at baseline showed no association with asthma control. Dexamethasone-induced CD4+ FKBP51 expression was associated with worse asthma control in obese participants with asthma. FKBP51 expression in CD8+ T cells and CD19+ B cells did not differ among groups, nor did polarization profiles for Th1, Th2, Th9, or Th17 percentage.

Discussion

Dexamethasone-induced CD4+ FKBP51 expression is uniquely associated with worse asthma control in obese children with asthma and may underlie the corticosteroid resistance observed in this population.

Predictive Value of Serum Lipid for Intravenous Immunoglobulin Resistance and Coronary Artery Lesion in Kawasaki Disease

CONTEXT

Intravenous immunoglobulin (IVIG) resistance and coronary artery lesions (CALs) prediction are pivotal topic of interests in Kawasaki disease (KD). However, data on the predictive value of lipid profile for both IVIG resistance and CALs are limited.

PURPOSE

To investigate the predictive validity of lipid profile for IVIG resistance and CALs in KD.

DESIGN

Prospective cohort study.

SETTING

West China Second University Hospital.

PATIENTS

363 KD patients were divided into the initial IVIG-resistant group and initial IVIG-responsive group; repeated IVIG-resistant group and repeated IVIG-responsive group; CAL+ group and CAL- group.

MAIN OUTCOME MEASURES

Validity of lipid profile in predicting IVIG resistance and CALs.

RESULTS

Triglycerides were significantly higher whereas total cholesterol (TC), high-densisty lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and apolipoprotein A (Apo A) were significantly lower in initial IVIG-resistant subjects, with cut-off values of 1.625 mmol/L, 3.255 mmol/L, 0.475 mmol/L, 1.965 mmol/L, and 0.665 g/L, yielding sensitivities of 52%, 70%, 52%, 61%, and 50% and specificities of 68%, 53%, 78%, 71%, and 81%, respectively. TC, LDL-C, and Apo A levels were significantly lower in repeated IVIG-resistant subjects, with cut-off values of 3.20 mmol/L, 1.78 mmol/L, and 0.605 g/L, producing sensitivities of 91%, 70%, and 57% and specificities of 55%, 67%, and 70%, respectively. Apo A level was significantly lower in the CAL+ group, with cut-off value of 0.805 g/L, yielding sensitivity of 66% and specificity of 54%.

CONCLUSIONS

Lipid profiles were significantly dysregulated in KD patients suffering IVIG resistance and CALs. Some of them, such as LDL-C and Apo A, could serve as complementary laboratory markers for predicting both IVIG resistance and CALs.

Non-epidemic HCV genotypes in low- and middle-income countries and the risk of resistance to current direct-acting antiviral regimens

The hepatitis C virus (HCV) is an extremely diverse virus, subtypes of which are distributed variably around the world. Viral genotypes may be divided into epidemic subtypes; those that have become prevalent globally, and endemic subtypes that have a more limited distribution, mainly in Africa and Asia. The high variability of endemic strains reflects evolutionary origins in the locations where they are found. This increased genetic diversity raises the possibility of resistance to pan-genotypic direct-acting antiviral regimens. While many endemic subtypes respond well to direct-acting antiviral therapies, others, for example genotypes 1l, 3b and 4r, do not respond as well as predicted. Many genotypes that are rare in high-income countries but common in other parts of the world have not yet been fully assessed in clinical trials. Further sequencing and clinical studies in sub-Saharan Africa and Asia are indicated to monitor response to treatment and to facilitate the World Health Organization's 2030 elimination strategy.

Immune selection suppresses the emergence of drug resistance in malaria parasites but facilitates its spread

Although drug resistance in Plasmodium falciparum typically evolves in regions of low transmission, resistance spreads readily following introduction to regions with a heavier disease burden. This suggests that the origin and the spread of resistance are governed by different processes, and that high transmission intensity specifically impedes the origin. Factors associated with high transmission, such as highly immune hosts and competition within genetically diverse infections, are associated with suppression of resistant lineages within hosts. However, interactions between these factors have rarely been investigated and the specific relationship between adaptive immunity and selection for resistance has not been explored. Here, we developed a multiscale, agent-based model of Plasmodium parasites, hosts, and vectors to examine how host and parasite dynamics shape the evolution of resistance in populations with different transmission intensities. We found that selection for antigenic novelty (“immune selection”) suppressed the evolution of resistance in high transmission settings. We show that high levels of population immunity increased the strength of immune selection relative to selection for resistance. As a result, immune selection delayed the evolution of resistance in high transmission populations by allowing novel, sensitive lineages to remain in circulation at the expense of the spread of a resistant lineage.

In contrast, in low transmission settings, we observed that resistant strains were able to sweep to high population prevalence without interference. Additionally, we found that the relationship between immune selection and resistance changed when resistance was widespread. Once resistance was common enough to be found on many antigenic backgrounds, immune selection stably maintained resistant parasites in the population by allowing them to proliferate, even in untreated hosts, when resistance was linked to a novel epitope. Our results suggest that immune selection plays a role in the global pattern of resistance evolution.

Drug resistance in the malaria parasite, Plasmodium falciparum, presents an ongoing public health challenge, but aspects of its evolution are poorly understood. Although antimalarial resistance is common worldwide, it can typically be traced to just a handful of evolutionary origins. Counterintuitively, although Sub Saharan Africa bears 90% of the global malaria burden, resistance typically originates in regions where transmission intensity is low. In high transmission regions, infections are genetically diverse, and hosts have significant standing adaptive immunity, both of which are known to suppress the frequency of resistance within infections. However, interactions between immune-driven selection, transmission intensity, and resistance have not been investigated. Using a multiscale, agent-based model, we found that high transmission intensity slowed the evolution of resistance via its effect on host population immunity. High host immunity strengthened selection for antigenic novelty, interfering with selection for resistance and allowing sensitive lineages to suppress resistant lineages in untreated hosts. However, once resistance was common in the circulating parasite population, immune selection maintained it in the population at a high prevalence. Our findings provide a novel explanation for observations about the origin of resistance and suggest that adaptive immunity is a critical component of selection.

Unfavorable impact of anti-rituximab antibodies on clinical outcomes in children with complicated steroid-dependent nephrotic syndrome

BACKGROUND

Anti-rituximab antibodies (ARA) are associated not only with adverse events, such as infusion reactions (IR) and serum sickness, but also with rituximab efficacy. However, the clinical relevance of ARA in children with steroid-dependent nephrotic syndrome (SDNS) remains unknown.

METHODS

We retrospectively reviewed clinical outcomes of 13 children with complicated SDNS receiving repeated single-dose rituximab treatments at 375 mg/m² to assess whether ARA formation could impact toxicity and efficacy of additional rituximab. Pre-rituximab 22 samples collected from patients who developed IR during the second or subsequent rituximab doses were measured by electrochemiluminescence analysis.

RESULTS

ARA were identified in 5 of 13 patients (9 of 22 samples). Median time to recovery of CD19⁺ B cells to > 1% of total lymphocytes and median relapse-free time after rituximab treatment were significantly shorter in the 9 ARA-positive samples than the 13 ARA-negative samples (41 vs. 100 days, p < 0.01 and 119 vs. 308 days, p < 0.05, respectively). Kaplan-Meier analysis showed that time to CD19+ B cell recovery after rituximab was significantly shorter in ARA-positive samples than in ARA-negative samples (p < 0.005). Severe IR developed in two ARA-positive patients and serum sickness in one ARA-positive patient.

CONCLUSIONS

The incidence of ARA formation was high in the pre-rituximab samples of patients with complicated SDNS who developed IR during the second or subsequent rituximab doses, suggesting that ARA formation might have an unfavorable impact on the toxicity and efficacy of additional rituximab doses in these patients.

Emerging Insights on the Interaction Between Anticancer and Immunosuppressant Drugs and Intestinal Microbiota in Pediatric Patients

Diseases affecting the immune system, such as inflammatory bowel disease (IBD), juvenile idiopathic arthritis (JIA), and acute lymphoblastic leukemia (ALL), are pathological conditions affecting the pediatric population and are often associated with alterations in the intestinal microbiota, such as a decrease in bacterial diversity. Growing evidence suggests that gut microbiota can interfere with chemotherapeutic and immunosuppressant drugs, used in the treatment of these diseases, reducing or facilitating drug efficacy. In particular, the effect of intestinal microflora through translocation, immunomodulation, metabolism, enzymatic degradation, and reduction of bacterial diversity seems to be one of the reasons of interindividual variability in the therapeutic response. Although the extent of the role of intestinal microflora in chemotherapy and immunosuppression remains still unresolved, current evidence on bacterial compositional shifts will be taken in consideration together with clinical response to drugs for a better and personalized therapy. This review is focused on the effect of the intestinal microbiota on the efficacy of pharmacological therapy of agents used to treat IBD, JIA, and ALL.

CD3-CD56+ NK cells display an inflammatory profile in RR-MS patients

Multiple Sclerosis (MS) is an immune-mediated and neurodegenerative disease of central nervous system. Relapsing-remitting (RR)-MS occurring with acute attacks and remissions, is the most common clinical type of MS. There are different strategies applied in first-line treatment of RR-MS patients such as interferon-beta (IFN-β) and glatiramer acetate. In this study, activating and inhibitory receptor expressions and interleukin (IL)-22 levels of NK cells were investigated in RR-MS patients with or without IFN-β therapy. Activating receptor expression and IL-22 levels of NK cells were increased in RR-MS patients under IFN-β therapy. Elevated NK cells with activating profile and increased IL-22 under IFN-β therapy suggest that IFN-β treatment might direct NK cells toward a pro-inflammatory status.

Interaction of the immune-inflammatory and the kynurenine pathways in rats resistant to antidepressant treatment in model of depression

The kynurenine pathway (KP), a major route of tryptophan catabolism, may be associated with the pathophysiology of depressive disorders. KP is responsible for ca. 99% of brain tryptophan metabolism via its degradation to kynurenine (KYN) catalyzed by indoleamine 2,3-dioxygenase (IDO). Some cytokines, such as interferon-γ (IFN-γ) and interleukin (IL)-6 are potent inducers of IDO. KYN is further converted by kynurenine aminotransferase (KAT) to the more neuroprotective kynurenic acid or by kynurenine 3-monooxygenase (KMO) to neurotoxic 3-hydroxykynurenine. The aim of the present study was to delineate whether the administration of imipramine (IMI) to rats subjected to chronic mild stress (CMS) may reverse behavioral changes induced by CMS in association with changes in immune-inflammatory markers and KP. We confirmed that the CMS procedure modeled one of the main symptoms of depression, i.e. anhedonia, and administration of IMI for 5 weeks resulted in a significant reduction in anhedonia in a majority of animals (CMS IMI-R animals), whereas 20% of animals did not respond to IMI treatment (CMS IMI-NR animals). We established that CMS procedure increased IFN-γ and IDO mRNA and decreased KAT II mRNA expression in the rat cortex. In the cortex and hippocampus, IMI treatment and non-responsiveness to IMI (in CMS IMI-NR animals) were associated with increased IL-6 mRNA expression. In the spleen, CMS increased production of IFN-γ and IL-6 proteins, while these cytokines were decreased by IMI in CMS IMI-R animals. Chronic IMI administration to CMS rats decreased IDO and KMO mRNA and protein expression and increased KAT II/KMO mRNA and protein ratio in IMI responders (CMS IMI-R) in comparison to CMS rats. In CMS IMI-NR rats, a significant increase in IDO mRNA expression and protein level in comparison with IMI responders was observed. Our findings indicate that resistance to therapeutic action of IMI could be explained by a deficiency of the inhibitory properties of IMI on IDO, KMO and KYN synthesis in the cortex. We conclude that the antidepressant activity of IMI may, at least in part, be explained by modulatory activities on the KAT II/KMO ratio in brain areas.

Efficacy of primary treatment with immunoglobulin plus ciclosporin for prevention of coronary artery abnormalities in patients with Kawasaki disease predicted to be at increased risk of non-response to intravenous immunoglobulin (KAICA): a randomised controlled, open-label, blinded-endpoints, phase 3 trial

BACKGROUND

Genetic studies have indicated possible involvement of the upregulated calcium-nuclear factor of activated T cells pathway in the pathogenesis of Kawasaki disease. We aimed to assess safety and efficacy of ciclosporin, an immunosuppressant targeting this pathway, for protection of patients with Kawasaki disease against coronary artery abnormalities.

METHODS

We did a randomised, open-label, blinded endpoints trial involving 22 hospitals in Japan between May 29, 2014, and Dec 27, 2016. Eligible patients predicted to be at higher risk for intravenous immunoglobulin (IVIG) resistance were randomly assigned to IVIG plus ciclosporin (5 mg/kg per day for 5 days; study treatment) or IVIG (conventional treatment) groups, stratified by risk score, age, and sex. The primary endpoint was incidence of coronary artery abnormalities using Japanese criteria during the 12-week trial, assessed in participants who received at least one dose of study drug and who visited the study institution at least once during treatment. This trial is registered to Center for Clinical Trials, Japan Medical Association, number JMA-IIA00174.

FINDINGS

We enrolled 175 participants. One patient withdrew consent after enrolment and was excluded and one patient (in the study treatment group) was excluded from analysis because of lost echocardiography data. Incidence of coronary artery abnormalities was lower in the study treatment group than in the conventional treatment group (12 [14%] of 86 patients vs 27 [31%] of 87 patients; risk ratio 0·46; 95% CI 0·25-0·86; p=0·010). No difference was found in the incidence of adverse events between the groups (9% vs 7%; p=0·78).

INTERPRETATION

Combined primary therapy with IVIG and ciclosporin was safe and effective for favourable coronary artery outcomes in Kawasaki disease patients who were predicted to be unresponsive to IVIG.

FUNDING

Japan Agency for Medical Research and Development (grant CCT-B-2503).

[Autoimmune factors and epilepsy]

Epilepsy is a common chronic brain disorder with multiple causes, and now autoimmune factors are believed to be an independent cause for epilepsy. Accumulating data support an autoimmune basis in patients with antiepileptic drug-resistant seizures. Moreover, systemic autoimmune diseases and epilepsy co-occur frequently. Neural specific autoantibodies can also mediate the process of seizures through different pathways. The diagnosis of autoimmune epilepsy is based on frequency of antiepileptic drug-resistant seizures, the presence of neural specific autoantibodies, inflammatory changes in serum or spinal fluid or on magneticresonanceimaging, the change in electroencephalogram, a personal or family history of autoimmunity. Once autoimmune epilepsy is diagnosed, the immunotherapy is required. Early immunotherapy is crucial for improving the prognosis of the patients.

Seroprevalence survey of selective anti-neuronal autoantibodies in patients with first-episode schizophrenia and chronic schizophrenia

Autoimmune encephalopathy caused by autoantibodies against neuronal cell-surface proteins in the brain is a newly discovered disease category associated with psychiatric disorders. Correct diagnosis of this condition relies on the detection of specific autoantibodies in the blood or cerebral spinal fluid in addition to the clinical presentations. The study aimed to understand the seroprevalence of selective anti-neuronal autoantibodies in our patients with schizophrenia. First, we screened for six anti-neuronal autoantibodies in an archived blood sample collected from patients with the first-episode schizophrenia. The six autoantibodies including antibodies against N-methyl-d-aspartate (NMDA) receptor, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors 1 and 2, γ-butyric acid receptor type B1 (GABARB1), leucine-rich glioma inactivated-1 (LGI1) protein, and contactin-associated protein-like 2 (CASPR2) protein. A total of 78 plasma samples (46 males and 32 females) were investigated; however, no positive case was identified. In this second study, we screened anti-NMDA receptor autoantibodies in a blood sample of 234 patients with chronic schizophrenia (133 females and 101 males) including 48 patients defined as treatment resistance. None of this sample was detected as positive. The negative findings in this study suggest that the seroprevalence of autoantibodies against neuronal surface proteins might be low in patients diagnosed with schizophrenia.

Increased Pretransplant Frequency of CD28+ CD4+ TEM Predicts Belatacept-Resistant Rejection in Human Renal Transplant Recipients

While most human T cells express the CD28 costimulatory molecule constitutively, it is well known that age, inflammation, and viral infection can drive the generation of CD28^null T cells. In vitro studies have demonstrated that CD28^null cell effector function is not impacted by the presence of the CD28 costimulation blocker belatacept. As such, a prevailing hypothesis suggests that CD28^null cells may precipitate costimulation blockade-resistant rejection. However, CD28⁺ cells possess more proliferative and multifunctional capacity, factors that may increase their ability to successfully mediate rejection. Here, we performed a retrospective immunophenotypic analysis of adult renal transplant recipients who experienced acute rejection on belatacept treatment as compared to those who did not. Intriguingly, our findings suggest that patients possessing higher frequency of CD28⁺ CD4⁺ T_EM prior to transplant were more likely to experience acute rejection following treatment with a belatacept-based immunosuppressive regimen. Mechanistically, CD28⁺ CD4⁺ T_EM contained significantly more IL-2 producers. In contrast, CD28^null CD4⁺ T_EM isolated from stable belatacept-treated patients exhibited higher expression of the 2B4 coinhibitory molecule as compared to those isolated from patients who rejected. These data raise the possibility that pretransplant frequencies of CD28⁺ CD4⁺ T_EM could be used as a biomarker to predict risk of rejection following treatment with belatacept.

Clinical impact of immunomonitoring in the treatment of inflammatory bowel disease

Despite improvement in outcomes, loss of response (LOR) to tumor necrosis factor-alpha (TNFα) therapies is a big concern in the management of inflammatory bowel disease. LOR is associated with flares of disease, increased hospitalisation rates, need for surgical interventions, and decline in quality of life. LOR may be multifactorial, but immunogenicity makes a significant contribution. Traditionally doses of anti-TNFα have been adjusted based on clinical response, using a standard approach. Immunomonitoring involves the measurement of anti-TNFα trough and antibody levels. It takes into account the underlying pharmacokinetics of anti-TNFα therapies. Expanding on this a treat to target approach may be used, where doses are intensified, or tailored to the individual based on the measurement of anti-TNFα trough and antibody levels. This review looks at the history, evolution, and clinical impact that immunomonitoring is having in the treatment of inflammatory bowel disease. It will focus on the role of immunomonitoring in helping to achieve long lasting deep remission and mucosal healing. It will explore the different options in terms of best measuring trough and antibody levels, explore possible advantages of immunomonitoring, and discuss its role in best optimising response, at induction, during the maintenance phase of treatment, as well as a role in withdrawing or switching therapy.

Risk Factor Analysis for the Immunogenicity of Adalimumab Associated with Decreased Clinical Response in Chinese Patients with Psoriasis

Although anti-drug antibodies against biologics have been associated with decreased clinical efficacy, the immunogenicity of biologics seems to vary between drugs, diseases and ethnicities. This study aims to investigate the predictors for the formation of anti-adalimumab antibodies (AAA) and the clinical consequences of AAA formation. In 53 Chinese psoriatic patients treated with adalimumab, AAA was detected in 50.9%. Differences in Psoriasis Area and Severity Index 75 (PASI75) response rates among patients with and without AAA were significant (44.4% vs. 88.5%; p = 0.001). Patients with AAA had significantly lower trough concentrations of adalimumab than those without AAA. Risk factor analysis showed that treatment interruption, low trough adalimumab concentration, absence of concomitant methotrexate use and biologics switching were associated with a higher AAA titre. The treatment pattern of biologics influences the risk of AAA formation, thereby leading to reduced efficacy of adalimumab.

Mass spectrometry-based proteomic analysis of Leishmania donovani soluble proteins in Indian clinical isolate

Leishmania donovani, a causative organism of visceral leishmaniasis (VL), is responsible for high mortality throughout the world. Due to the unsatisfactory treatment measures and increasing drug resistance, there has been an urgent need to develop novel drug/vaccine targets against VL. The aim of this study was to identify novel targets in soluble L. donovani (SLD) protein. SLD protein was isolated and resolved by two-dimensional gel electrophoresis and analyzed through MALDI-TOF/TOF-based mass spectrometry. Proteomic results identified several proteins as drug targets, Th1 stimulatory, novel, and hypothetical proteins which could have crucial biological functions in Leishmania pathogenesis.

Detection of antibodies to anti-TNF agents in psoriatic patients: a preliminary study

AIM

The efficacy of anti-TNFα agents in psoriasis (Pso) has been established in different clinical trials and in every day practice. However, a portion of patients (non-responder patients) persists with active disease or relapses even during current biological therapy. In addition to this, the use of biologic agents can give adverse drug reactions. All these factors may be due to the immunogenicity of these new biological drugs. All the biological proteins, including fully human proteins, have the potential to induce immunogenicity which leads to the development of specific antidrug antibodies (ADAs).

METHODS

In a retrospective way, we studied ADAs, using ELISA test, in a group of 51 patients with moderate to severe Pso treated with anti TNF α drugs: 18 Etanercept (ETN), 15 infliximab (IFX) and 18 adalimumab (AdA).

RESULTS

Anti-IFX antibodies were positive in 13.3%, anti AdA in 16.6% while all the patients treated with ETN did not present ADAs. Our opinion is that it is important to verify non-responder patients due to neutralizing ADAs so that we can change the drug before patients get worse. Moreover, it is important to detect ADAs since positive patients are more likely to develop acute hypersensitivity reactions. The development of antimonoclonal specific IgGs may also lead to an effector mechanism involving complement activation and production of anaphylotoxins which determine side effects that can be, in some cases, very severe. ADAs can be responsible of the poor response to the drugs and can impact the safety profile of the drugs.

CONCLUSION

We think that the detection of ADAs will be useful for the management of the drugs and the disease in all patients with psoriasis in treatment with anti biological drugs as a routine clinical practice.

Prevention of thrombosis relapse in antiphospholipid syndrome patients refractory to conventional therapy using intravenous immunoglobulin

OBJECTIVES

To investigate the long-term effects of megadoses of intravenous immunoglobulin (IVIG) in a small cohort of patients with relapsing primary APS resistant to conventional treatments.

METHODS

Five primary APS patients, 4 women, mean age 45.1 years (range 31-76 years), were considered eligible for IVIG therapy due to relapsing thrombotic events (4 recurrent venous thromboses, 2 ischaemic cerebral strokes, 2 pulmonary thromboembolisms, 1 thrombotic event on the vena cava filter), despite conventional therapy with anticoagulants. All patients had anti-nuclear antibodies at low-medium titre without other signs or symptoms of systemic lupus erythematosus. IVIG was combined with hydroxychloroquine and, in patients with cerebral strokes, acetylsalicylic acid. Three consecutive daily infusions of IVIG were administered intravenously at a dose of 0.4 g/kg/day every month for 3 months, followed by a single monthly infusion for 9 months.

RESULTS

No further thromboses occurred in the 5 treated patients (mean follow-up 89.2 months, range 61-114). Visual analogue score (VAS 0-10) improved (mean 3.5, range 3.0-5.0, before, and 7.35, range 9.9-6.0, p= 0.05) after IVIG treatment.

CONCLUSIONS

In a long-term (>5 years) open study in a small cohort of high risk primary APS patients, IVIG was found to be effective in preventing recurrent thrombosis. Full understanding of the mechanisms and efficacy, as well as the optimal doses of IVIG in APS patients with recurrent thrombosis, will require appropriately designed clinical studies. Presently, IVIG use is restricted by costs and limited availability.

Glucocorticoid receptors and the pattern of steroid response in idiopathic nephrotic syndrome

INTRODUCTION

Little is known about the relationships between the T lymphocytes (CD3+) expression of glucocorticoid receptors (GCR) and the response to glucocorticoid treatment in children with idiopathic nephrotic syndrome (NS). The aim of the current study is to determine whether steroid responsiveness is dependent on the amount of T lymphocytes GCR expression.

METHODS

We studied 60 children with idiopathic NS in the age group from 2-10 years. According to the response to steroids we classified our patients into early responders (ER; n = 46) and late responders (LR; n = 14). Sixty age and gender matched healthy children represented the control group. The clinical and laboratory findings at baseline and GCR expression by T lymphocytes (CD3+) as determined by flow cytometry were compared between the three groups.

RESULTS

The T lymphocytes (CD3+) expression of GCR was significantly lower in the LR than that in the control group (P < 0.01), whereas it was similar in the ER and control groups. GCR expression was also decreased in the LR group compared to the ER group (P < 0.01). Furthermore, the T lymphocytes (CD3+) expression of GCR correlated inversely with the time to complete remission (CR) (r = -0.54, P < 0.05), but not with urinary protein excretion at baseline.

CONCLUSION

The levels of T lymphocytes (CD3+) expression of GCR may be a useful predictor of steroid responsiveness in children presenting with idiopathic NS.

Steroid-refractory acute GVHD: lack of long-term improved survival using new generation anticytokine treatment

There is no consensus on the optimal treatment of steroid-refractory acute graft-versus-host disease (SR-aGVHD) after allogeneic hematopoietic stem cell transplantation. In our center, the treatment policy has changed over time with mycophenolate mofetil (MMF) being used from 1999 to 2003, and etanercept or inolimomab after 2004. An observational study compared survival and infection rates in all consecutive patients receiving 1 of these 3 treatments. Ninety-three patients were included. The main end point was overall survival (OS). Median age was 37 years. Acute GVHD developed at a median of 15 days after transplantation. Second-line treatment was initiated a median of 12 days after aGVHD diagnosis. Therapies were MMF in 56%, inolimomab in 22%, and etanercept in 23% of the patients. Overall, second-line treatment response rate was 45% (complete response: 28%), MMF: 55%, inolimomab: 35%, and etanercept: 28%. With 74 months median follow-up, the 2-year survival was 30% (95% confidence interval: 22-41). Risk factors significantly associated with OS in multivariate analysis were disease status at transplantation; grade III-IV aGVHD at second-line treatment institution; and liver involvement. None of the second-line therapy influenced this poor outcome. Viral and fungal infections were not statistically different among the 3 treatment options; however, bacterial infections were more frequent in patients treated with anticytokines. Over an 11-year period, 3 treatment strategies, including 2 anticytokines, give similar results in patients with SR-aGVHD.

Efficacy of adalimumab in patients with Behçet's disease unsuccessfully treated with infliximab

OBJECTIVES

To evaluate the clinical response after switching from infliximab to adalimumab in patients with Behçet's disease (BD).

METHODS

In this ongoing, prospective, longitudinal and observational study, data were collected on efficacy and safety of every patient with BD beginning anti-TNF therapy in the last 8 years. The present analysis was restricted to patients who were switched to adalimumab after failing or not tolerating infliximab.

RESULTS

A total of 69 patients with BD have been treated with infliximab so far. Seventeen of these (25%) have been switched to adalimumab for lack or loss of efficacy or infusion reactions. In 10 out of these 17, the main manifestations requiring switching were the mucocutaneous lesions, in 4 retinal vasculitis and in 3 the neurological involvement. Of the 17 treated patients, 9 showed sustained remission of the disease and 3 a good response. No side effects were observed in any patient.

CONCLUSIONS

The results of our study suggest that patients with BD showing a scarce response or adverse events to infliximab may successfully be treated with adalimumab, regardless of the reason for switching.

Th17: contributors to allograft rejection and a barrier to the induction of transplantation tolerance?

T helper (Th) type 17 cells are a recently described CD4 T-cell subset that may contribute to allograft rejection and act as a barrier to the induction of transplant tolerance. This review examines the involvement of Th17 cells in transplant rejection, how immunosuppressive medication may affect their induction and maintenance and the potential plasticity of developing Th17 cells. It also addresses the complex interplay between the Th17 and regulatory T-cell developmental pathways and the susceptibility of Th17 cells to regulation. Despite accumulating evidence, the precise impact of Th17 cells on transplant rejection and the induction of tolerance require further clarification.

Safety and clinical outcomes of rituximab therapy in patients with different autoimmune diseases: experience from a national registry (GRAID)

INTRODUCTION

Evidence from a number of open-label, uncontrolled studies has suggested that rituximab may benefit patients with autoimmune diseases who are refractory to standard-of-care. The objective of this study was to evaluate the safety and clinical outcomes of rituximab in several standard-of-care-refractory autoimmune diseases (within rheumatology, nephrology, dermatology and neurology) other than rheumatoid arthritis or non-Hodgkin's lymphoma in a real-life clinical setting.

METHODS

Patients who received rituximab having shown an inadequate response to standard-of-care had their safety and clinical outcomes data retrospectively analysed as part of the German Registry of Autoimmune Diseases. The main outcome measures were safety and clinical response, as judged at the discretion of the investigators.

RESULTS

A total of 370 patients (299 patient-years) with various autoimmune diseases (23.0% with systemic lupus erythematosus, 15.7% antineutrophil cytoplasmic antibody-associated granulomatous vasculitides, 15.1% multiple sclerosis and 10.0% pemphigus) from 42 centres received a mean dose of 2,440 mg of rituximab over a median (range) of 194 (180 to 1,407) days. The overall rate of serious infections was 5.3 per 100 patient-years during rituximab therapy. Opportunistic infections were infrequent across the whole study population, and mostly occurred in patients with systemic lupus erythematosus. There were 11 deaths (3.0% of patients) after rituximab treatment (mean 11.6 months after first infusion, range 0.8 to 31.3 months), with most of the deaths caused by infections. Overall (n = 293), 13.3% of patients showed no response, 45.1% showed a partial response and 41.6% showed a complete response. Responses were also reflected by reduced use of glucocorticoids and various immunosuppressives during rituximab therapy and follow-up compared with before rituximab. Rituximab generally had a positive effect on patient well-being (physician's visual analogue scale; mean improvement from baseline of 12.1 mm).

CONCLUSIONS

Data from this registry indicate that rituximab is a commonly employed, well-tolerated therapy with potential beneficial effects in standard of care-refractory autoimmune diseases, and support the results from other open-label, uncontrolled studies.

Successful treatment of cyclosporine-A-resistant cytophagic histiocytic panniculitis with tacrolimus

A 34-year-old woman with discoid lupus erythematosus and lupus profundus was admitted to our hospital showing signs of a fever, malaise, and abdominal swelling. Diagnosis of cytophagic histiocytic panniculitis (CHP) was made based on lobular panniculitis with a hemophagocytosis. Treatment with high doses of prednisolone combined with cyclosporine A (CsA) was not effective enough. However, after changing CsA to tacrolimus (TAC), CHP improved. Our case demonstrates that TAC may be a novel therapy for CHP.

Do biologics-naïve patients with rheumatoid arthritis respond better to tocilizumab than patients for whom anti-TNF agents have failed? A retrospective study

OBJECTIVES

To determine responses to tocilizumab between patients with rheumatoid arthritis (RA) who switched to anti-TNF agents and those who are biologics-naïve.

METHODS

This retrospective study investigated 107 patients with RA who were treated with tocilizumab. At baseline, 61 of them had already been treated with anti-TNF agents (switched group; 46 for inefficacy and 15 for adverse events), and 46 were biologics-naïve (naïve group). Treatment responses to tocilizumab at week 12 and 24 were compared between the switched and naïve groups using the disease activity score 28 (DAS28).

RESULTS

Forty-two (91.3%) and 50 (82.0%) patients in the naïve and switched groups, respectively, completed 24 weeks of tocilizumab treatment. The DAS28-ESR and DAS28-CRP values (means±SD) at weeks 12 and 24 compared to baseline decreased significantly for the naïve and switched groups. The DAS28-ESR and DAS28-CRP values at weeks 12 and 24 were significantly decreased in the naïve group, compared to the switched group. Disease activity was improved in the naïve patients compared to the switched patients.

CONCLUSIONS

Tocilizumab was safe, tolerable, and clinically effective for patients with inadequate responses to anti-TNF therapy and for those who were biologics-naïve, and it was more effective among the latter.

Super-high-dose methylprednisolone does not improve efficacy or induce glucocorticoid resistance in experimental allergic encephalomyelitis

OBJECTIVE

To investigate whether a super-high dose (SHD) of methylprednisolone (MP) improves its efficacy or induces glucocorticoid (GC) resistance, and to explore the potential mechanisms of GC resistance in experimental allergic encephalomyelitis (EAE).

METHODS

The therapeutic effects of SHD and low-dose MP were evaluated in EAE by analyzing clinical scores, pathological changes and cytokine production. Immunohistochemistry and RT-PCR were used to investigate the expression of GC receptor (GR) isoforms and splicing factor SRp30c.

RESULTS

Both MP doses had similar therapeutic effects. The ratio of GRα to GRβ was positively correlated with clinical score changes. However, there was no difference in the GRα/GRβ ratio between SHD and low-dose MP groups. SRp30c mRNA was correlated with GRβ expression.

CONCLUSION

This study indicates that the GRα/GRβ ratio is associated with GC sensitivity, and SRp30c may play an important role in promoting alternative splicing of GR pre-mRNA to generate GRβ in EAE rats. Compared with low-dose MP, SHD MP does not improve efficacy or induce GC resistance.

Differential susceptibility to nitric oxide-evoked apoptosis in human inflammatory cells

Apoptosis of neutrophils and their subsequent phagocytosis is critical to the successful resolution of inflammation. During inflammation, activated inflammatory cells generate reactive oxygen and nitrogen species, including nitric oxide (NO) and superoxide anion (O(2)(•-)), which rapidly combine to generate peroxynitrite (ONOO(-)). NO and ONOO(-) are proapoptotic in human neutrophils. This study examines the effects of NO and ONOO(-) on caspase activation and mitochondrial permeability in human neutrophils and determines the ability of these species to evoke apoptosis in human monocyte-derived macrophages (MDMs). NO or ONOO(-) release from donor compounds was characterized by electrochemistry and electron paramagnetic resonance. Neutrophils and MDMs isolated from the peripheral blood of healthy volunteers were exposed to NO or ONOO(-) before analysis of apoptosis by caspase activation, mitochondrial permeability, and annexin V binding. Both NO and ONOO(-) induced apoptosis via rapid activation of caspases 2 and 3 in neutrophils. In contrast, only ONOO(-) promoted apoptosis in MDMs, whereas a variety of NO donors were ineffective at inducing apoptosis in this cell type. We propose that human macrophages are refractory to NO-stimulated apoptosis in order that they persist long enough within the inflammatory focus to phagocytose apoptotic neutrophils, thereby ensuring successful resolution of inflammation.

Prolonged improvement after rituximab: two cases of resistant muscle-specific receptor tyrosine kinase + myasthenia gravis

Forty percent to 50% of acetylcholine receptor antibody-seronegative patients with myasthenia gravis have muscle-specific receptor tyrosine kinase antibodies. Many muscle-specific receptor tyrosine kinase + myasthenia gravis patients remain refractory with conventional therapies. Rituximab is an anti-CD20 monoclonal antibody used in refractory B-cell disorders. Currently there is no standard dosing schedule for rituximab. We present two muscle-specific receptor tyrosine kinase + myasthenia gravis patients clinically refractory to conventional therapy who, after a single course of rituximab, became asymptomatic and discontinued all medication.

The human trypanolytic factor: a drug shaped naturally

African trypanosomes are responsible for sleeping sickness in man and nagana in cattle, which are both tremendous health burdens in Africa. Most African trypanosome species are killed by human serum. This is due to a serum trypanolytic particle specific of some old world monkeys and great apes, an HDL subclass containing two proteins which appeared recently in mammalian evolution, apolipoprotein L1 and haptoglobin related protein. Nevertheless, two African trypanosome species, Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense are able to infect humans, because they developed resistance to trypanolysis. Resistance to human serum in Trypanosoma brucei rhodesiense is due to a single gene called SRA. This mechanism of lysis-resistance is therefore an example of a natural drug-antidote system which evolved during a pathogen-host arms race. The lysis and resistance mechanisms, their molecular components as well as their mode of action are reviewed. I also discuss how components of the system would be suitable drug targets and how the system could be engineered to generate an effective synthetic drug.

Effect of heterogeneous mixing and vaccination on the dynamics of anthelmintic resistance: a nested model

Anthelmintic resistance is a major threat to current measures for helminth control in humans and animals. The introduction of anthelmintic vaccines, as a complement to or replacement for drug treatments, has been advocated as a preventive measure. Here, a computer-based simulation, tracking the dynamics of hosts, parasites and parasite-genes, shows that, depending on the degree of host-population mixing, the frequency of totally recessive autosomes associated with anthelmintic resistance can follow either a fast dynamical regime with a low equilibrium point or a slow dynamical regime with a high equilibrium point. For fully dominant autosomes, only one regime is predicted. The effectiveness of anthelminthic vaccines against resistance is shown to be strongly influenced by the underlying dynamics of resistant autosomes. Vaccines targeting adult parasites, by decreasing helminth fecundity or lifespan, are predicted to be more effective than vaccines targeting parasite larvae, by decreasing host susceptibility to infection, in reducing the spread of resistance. These results may inform new strategies to prevent, monitor and control the spread of anthelmintic resistance, including the development of viable anthelmintic vaccines.

When the Guillain-Barre patient fails to respond to treatment

Most patients with Guillain-Barré syndrome (GBS) respond to treatment with intravenous immunoglobulin, but it is not uncommon for some to continue to deteriorate for a period after treatment has been started. This may reflect the natural history of the disease, or an error in diagnosis. This article reflects my own view of what to do in this situation, with a review of what few data there are to guide decision making.

A model for transmission of partial resistance to anti-malarial drugs

Anti-malarial drug resistance has been identified in many regions for a long time. In this paper we formulate a mathematical model of the spread of anti-malarial drug resistance in the population. The model is suitable for malarial situations in developing countries. We consider the sensitive and resistant strains of malaria. There are two basic reproduction ratios corresponding to the strains. If the ratios corresponding to the infections of the sensitive and resistant strains are not equal and they are greater than one, then there exist two endemic non-coexistent equilibria. In the case where the two ratios are equal and they are greater than one, the coexistence of the sensitive and resistant strains exist in the population. It is shown here that the recovery rates of the infected host and the proportion of anti-malarial drug treatment play important roles in the spread of anti-malarial drug resistance. The interesting phenomena of ''long-time" coexistence, which may explain the real situation in the field, could occur for long period of time when those parameters satisfy certain conditions. In regards to control strategy in the field, these results could give a good understanding of means of slowing down the spread of anti-malarial drug resistance.

Long-term remission of severe refractory dermatopolymyositis with a weekly-scheme of immunoglobulin followed by rituximab therapy

We report on a 44-year-old woman affected by dermatopolymyositis resistant to conventional therapies who experienced long-term clinical improvement and remission after treatment with intravenous polyvalent immunoglobulin in a weekly schedule followed by rituximab therapy.

Glucocorticoid resistance in inflammatory diseases

Glucocorticoid resistance or insensitivity is a major barrier to the treatment of several common inflammatory diseases-including chronic obstructive pulmonary disease and acute respiratory distress syndrome; it is also an issue for some patients with asthma, rheumatoid arthritis, and inflammatory bowel disease. Several molecular mechanisms of glucocorticoid resistance have now been identified, including activation of mitogen-activated protein (MAP) kinase pathways by certain cytokines, excessive activation of the transcription factor activator protein 1, reduced histone deacetylase-2 (HDAC2) expression, raised macrophage migration inhibitory factor, and increased P-glycoprotein-mediated drug efflux. Patients with glucocorticoid resistance can be treated with alternative broad-spectrum anti-inflammatory treatments, such as calcineurin inhibitors and other immunomodulators, or novel anti-inflammatory treatments, such as inhibitors of phosphodiesterase 4 or nuclear factor kappaB, although these drugs are all likely to have major side-effects. An alternative treatment strategy is to reverse glucocorticoid resistance by blocking its underlying mechanisms. Some examples of this approach are inhibition of p38 MAP kinase, use of vitamin D to restore interleukin-10 response, activation of HDAC2 expression by use of theophylline, antioxidants, or phosphoinositide-3-kinase-delta inhibitors, and inhibition of macrophage migration inhibitory factor and P-glycoprotein.

The definition of non-responder to multiple sclerosis treatment: neuroimaging markers

MRI is the main paraclinical tool used both to diagnose multiple sclerosis (MS) and to evaluate the efficacy of experimental treatments in phase II and III clinical trials. In the latter context, a major issue is represented by the weak correlations found between clinical and MRI aspects in the case of established MS, which are particularly evident when individual patients are considered. As a consequence, the definition of response to MS treatment, when based upon MRI aspects, remains a challenging task. Although the use of MRI-derived quantities to define treatment options and strategies at an individual patient level is supported by recent evidence, only the integration of clinical and MRI data can be considered a reliable approach for the work-up of patients undergoing disease-modifying treatments.

Genetic analysis of human traits in vitro: drug response and gene expression in lymphoblastoid cell lines

Lymphoblastoid cell lines (LCLs), originally collected as renewable sources of DNA, are now being used as a model system to study genotype–phenotype relationships in human cells, including searches for QTLs influencing levels of individual mRNAs and responses to drugs and radiation. In the course of attempting to map genes for drug response using 269 LCLs from the International HapMap Project, we evaluated the extent to which biological noise and non-genetic confounders contribute to trait variability in LCLs. While drug responses could be technically well measured on a given day, we observed significant day-to-day variability and substantial correlation to non-genetic confounders, such as baseline growth rates and metabolic state in culture. After correcting for these confounders, we were unable to detect any QTLs with genome-wide significance for drug response. A much higher proportion of variance in mRNA levels may be attributed to non-genetic factors (intra-individual variance—i.e., biological noise, levels of the EBV virus used to transform the cells, ATP levels) than to detectable eQTLs. Finally, in an attempt to improve power, we focused analysis on those genes that had both detectable eQTLs and correlation to drug response; we were unable to detect evidence that eQTL SNPs are convincingly associated with drug response in the model. While LCLs are a promising model for pharmacogenetic experiments, biological noise and in vitro artifacts may reduce power and have the potential to create spurious association due to confounding.

The use of lymphoblastoid cell lines (LCLs) has evolved from a renewable source of DNA to an in vitro model system to study the genetics of gene expression, drug response, and other traits in a controlled laboratory setting. While convincing relationships between SNPs and mRNA levels (eQTLs) have been described, the degree to which non-genetic variables also influence phenotypes in LCLs is less well characterized. In the course of attempting to map genes for drug responses in vitro, we evaluated the reproducibility of in vitro traits across replicates, the impact of the EBV virus used to transform B cells into cell lines, and the effect of in vitro culture conditions. We found that responses to at least some drugs and levels of many mRNAs can be technically well measured, but vary both across experiments and with non-genetic confounders such as growth rates, EBV levels, and ATP levels. The influence of such non-genetic factors can both decrease power to detect true relationships between DNA variation and traits and create the potential for non-genetic confounding and spurious associations between DNA variants and traits.

Neuromuscular paralysis and recovery in mice injected with botulinum neurotoxins A and C

Botulinum neurotoxin type A (BoNT/A) is commonly used in human therapy. This treatment may induce immunoresistance and preliminary evaluation of other botulinum neurotoxin serotypes suggested botulinum neurotoxin type C (BoNT/C) to be a good alternative to BoNT/A. Here, we have further characterized the biological activities of BoNT/C using a variety of experimental approaches. Muscle paralysis and time of recovery of mouse hind limb injected with BoNT/A or BoNT/C were assayed with the Digit Abduction Scoring assay. The extent and duration of paralysis were similar with the two toxin serotypes. Extensor digitorum longus or tibialis anterior muscles were dissected at times of complete paralysis and of complete recovery. Muscle weight and force were significantly reduced in mice injected with BoNT/A and BoNT/C, and some atrophy persisted for a long time. In BoNT/C-treated junctions, nerve terminal sprouting was prominent, indicating that the capacity to extend the field of innervation is not hampered by BoNT/C. BoNT/C induced a marked decrease in the frequency of miniature endplate potentials and in the amplitude of endplate potentials. 3,4-diaminopyridine reversed the effect of BoNT/C by increasing the amplitude of synchronized endplate potentials. The present study shows an extensive similarity in the biological activities of BoNT/A and BoNT/C, further supporting the suggestion that BoNT/C is a valid alternative to BoNT/A.