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Background: Granulomatous syndromes, such as Wegener's granulomatosis, are defined according to complex criteria, but the underlying cause is rarely identified. We present evidence for a new aetiology for chronic granulomatous lesions associated with a recessive genetic defect, which is linked to the human leucocyte antigen (HLA) locus.Methods: Five adults with necrotising granulomatous lesions in the upper respiratory tract and skin, associated with recurrent bacterial respiratory infections and skin vasculitis, were identified. A diagnosis of Wegener's granulomatosis was considered in all of them, but abandoned because of an incompatible disease course and resistance to immunosuppressive treatments. Peripheral-blood samples were taken and analysed by immunohistochemistry and fluorescent-activated-cell-sorter analysis. Since all five patients were homozygous for the HLA locus, we looked for genetic defects located within the HLA-locus with PCR and restriction fragment length polymorphism.Findings: A severe decrease in cell-surface expression of HLA class-I molecule was seen in all patients. Defective expression of the transporter associated with antigen presentation (TAP) genes was responsible for the HLA class-I down-regulation, and in two patients we identified a mutation in the TAP2 gene responsible for the defective expression of the TAP complex. We showed the presence of autoreactive natural killer (NK) cells and gammadelta T lymphocytes in the peripheral blood cells of two patients. Correction of the genetic defect in vitro restored normal expression of HLA class-I molecules and prevented self-reactivity in the patients' cells. Histology of granulomatous lesions showed the presence of a large proportion of activated NK cells.Interpretation: Our findings define the cause and pathogenesis of a new syndrome that affects patients with a defective surface expression of HLA class-I molecules. The syndrome resembles Wegener's granulomatosis both clinically and histologically. Patients have chronic necrotising granulomatous lesions in the upper respiratory tract and skin, recurrent infections of the respiratory tract, and skin vasculitis. A predominant NK population within the granulomatous lesions suggests that the pathophysiology of the skin lesions may relate to the inability of HLA class-I molecules to turn off NK cell responses. Accurate genetic analysis of a defined syndrome can provide a better understanding of the cause and pathogenesis of a disease. [ABSTRACT FROM AUTHOR]

Background: Doxycycline is often used for treating COVID-19 respiratory symptoms in the community despite an absence of evidence from clinical trials to support its use. We aimed to assess the efficacy of doxycycline to treat suspected COVID-19 in the community among people at high risk of adverse outcomes., Methods: We did a national, open-label, multi-arm, adaptive platform randomised trial of interventions against COVID-19 in older people (PRINCIPLE) across primary care centres in the UK. We included people aged 65 years or older, or 50 years or older with comorbidities (weakened immune system, heart disease, hypertension, asthma or lung disease, diabetes, mild hepatic impairment, stroke or neurological problem, and self-reported obesity or body-mass index of 35 kg/m 2 or greater), who had been unwell (for ≤14 days) with suspected COVID-19 or a positive PCR test for SARS-CoV-2 infection in the community. Participants were randomly assigned using response adaptive randomisation to usual care only, usual care plus oral doxycycline (200 mg on day 1, then 100 mg once daily for the following 6 days), or usual care plus other interventions. The interventions reported in this manuscript are usual care plus doxycycline and usual care only; evaluations of other interventions in this platform trial are ongoing. The coprimary endpoints were time to first self-reported recovery, and hospitalisation or death related to COVID-19, both measured over 28 days from randomisation and analysed by intention to treat. This trial is ongoing and is registered with ISRCTN, 86534580., Findings: The trial opened on April 2, 2020. Randomisation to doxycycline began on July 24, 2020, and was stopped on Dec 14, 2020, because the prespecified futility criterion was met; 2689 participants were enrolled and randomised between these dates. Of these, 2508 (93·3%) participants contributed follow-up data and were included in the primary analysis: 780 (31·1%) in the usual care plus doxycycline group, 948 in the usual care only group (37·8%), and 780 (31·1%) in the usual care plus other interventions group. Among the 1792 participants randomly assigned to the usual care plus doxycycline and usual care only groups, the mean age was 61·1 years (SD 7·9); 999 (55·7%) participants were female and 790 (44·1%) were male. In the primary analysis model, there was little evidence of difference in median time to first self-reported recovery between the usual care plus doxycycline group and the usual care only group (9·6 [95% Bayesian Credible Interval [BCI] 8·3 to 11·0] days vs 10·1 [8·7 to 11·7] days, hazard ratio 1·04 [95% BCI 0·93 to 1·17]). The estimated benefit in median time to first self-reported recovery was 0·5 days [95% BCI -0·99 to 2·04] and the probability of a clinically meaningful benefit (defined as ≥1·5 days) was 0·10. Hospitalisation or death related to COVID-19 occurred in 41 (crude percentage 5·3%) participants in the usual care plus doxycycline group and 43 (4·5%) in the usual care only group (estimated absolute percentage difference -0·5% [95% BCI -2·6 to 1·4]); there were five deaths (0·6%) in the usual care plus doxycycline group and two (0·2%) in the usual care only group., Interpretation: In patients with suspected COVID-19 in the community in the UK, who were at high risk of adverse outcomes, treatment with doxycycline was not associated with clinically meaningful reductions in time to recovery or hospital admissions or deaths related to COVID-19, and should not be used as a routine treatment for COVID-19., Funding: UK Research and Innovation, Department of Health and Social Care, National Institute for Health Research., Competing Interests: Declaration of interests BRS, MAD, CS, MF, and NB report grants from University of Oxford, for the sponsor's grant from the UK National Institute for Health Research (NIHR), for statistical design and analyses for the trial, during the conduct of the study. RD reports grants and personal fees from Synairgen, during the conduct of the study; personal fees from TEVA Pharmaceuticals, Sanofi, Boehringer, and Novartis, outside of the submitted work; and grants from the Innovative Medicines Initiative, the UK Medical Research Council, and Novartis, outside of the submitted work. FDRH reports grants from UK Research and Innovation (UKRI), during the conduct of the study. OVH reports grants from UKRI, outside of the submitted work. All other authors declare no competing interests., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Tuberculosis (TB), caused by Mycobacterium tuberculosis , remains a major human pandemic. Germline-encoded mycolyl lipid-reactive (GEM) T cells are donor-unrestricted and recognize CD1b-presented mycobacterial mycolates. However, the molecular requirements governing mycolate antigenicity for the GEM T cell receptor (TCR) remain poorly understood. Here, we demonstrate CD1b expression in TB granulomas and reveal a central role for meromycolate chains in influencing GEM-TCR activity. Meromycolate fine structure influences T cell responses in TB-exposed individuals, and meromycolate alterations modulate functional responses by GEM-TCRs. Computational simulations suggest that meromycolate chain dynamics regulate mycolate head group movement, thereby modulating GEM-TCR activity. Our findings have significant implications for the design of future vaccines that target GEM T cells., Competing Interests: The authors declare no conflict of interest.

Background: Rheumatologists increasingly perform ultrasound (US) imaging to aid diagnosis and management decisions. There is a need to determine the role of US in facilitating early diagnosis of inflammatory arthritis. This study describes the impact of US use by rheumatologists on diagnosis and management of inflammatory arthritis in routine UK clinical practice., Methods: We conducted a prospective study in four secondary care rheumatology clinics, each with one consultant who routinely used US and one who did not. Consenting patients aged > 18, newly referred with suspected inflammatory arthritis were included. Data were collected both retrospectively from medical records and via a prospectively-completed physician questionnaire on US use. Analyses were stratified by US/non-US groups and by sub-population of rheumatoid arthritis (RA)-diagnosed patients., Results: 258 patients were included; 134 US and 124 non-US. 42% (56/134) of US and 47% (58/124) of non-US were diagnosed with RA. Results described for US and non-US cohorts, respectively as follows. The proportion of patients diagnosed at their first clinic visit was 37% vs 19% overall (p = 0.004) and 41% vs 19% in RA-diagnosed patients (p = 0.01). The median time to diagnosis (months) was 0.85 vs 2.00 (overall, p = 0.0046) and 0.23 vs 1.38 (RA-diagnosed, p = 0.0016). Median time (months) to initiation on a DMARD (where initiated) was 0.62 vs 1.41 (overall, p = 0.0048) and 0.46 vs 1.81 (RA-diagnosed, p = 0.0007)., Conclusion: In patients with suspected inflammatory arthritis, routine US use in newly referred patients seems to be associated with significantly earlier diagnosis and DMARD initiation.

Correlates of immune protection that reliably predict vaccine efficacy against Mycobacterium tuberculosis (Mtb) infection are urgently needed. Invariant NKT cells (iNKTs) are CD1d-dependent innate T cells that augment host antimicrobial immunity through production of cytokines, including interferon (IFN)-γ and tumour necrosis factor (TNF)-α. We determined peripheral blood iNKT numbers, their proliferative responses and iNKT subset proportions after in vitro antigen expansion by α-galactosylceramide (αGC) in a large cohort of mycobacteria-naïve non-human primates, and macaques from Bacillus Calmette-Guerin (BCG) vaccine and Mtb challenge studies. Animals studied included four genetically distinct groups of macaques within cynomolgus and rhesus species that differ in their susceptibility to Mtb infection. We demonstrate significant differences in ex vivo iNKT frequency between groups, which trends towards an association with susceptibility to Mtb, but no significant difference in overall iNKT proliferative responses. Susceptible animals exhibited a skewed CD4 + /CD8 + iNKT subset ratio in comparison to more Mtb-resistant groups. Correlation of iNKT subsets post BCG vaccination with clinical disease manifestations following Mtb challenge in the Chinese cynomolgus and Indian rhesus macaques identified a consistent trend linking increased CD8 + iNKTs with favourable disease outcome. Finally, a similar iNKT profile was conferred by BCG vaccination in rhesus macaques. Our study provides the first detailed characterisation of iNKT cells in macaque tuberculosis infection, suggesting that iNKT repertoire differences may impact on disease outcome, which warrants further investigation., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Common variable immunodeficiency (CVID) is the commonest symptomatic primary antibody disorder, with monogenic causes identified in less than 10% of all cases. X-linked proliferative disease is a monogenic disorder that is associated with hypogammaglobulinemia and characterized by a deficiency of invariant NKT (iNKT) cells. We sought to evaluate whether a defect in iNKT cell number or function was associated with CVID., Objective: An evaluation of the function and number of iNKT cells in CVID., Methods: Six-color flow cytometry enumerated iNKT cells in 36 patients with CVID and 50 healthy controls. Their proliferative capacity and cytokine production (IFN-γ, IL-13, IL-17) was then investigated following activation with CD1d ligand alpha-galactosylceramide., Results: A reduction in the number of iNKT cells (31 iNKT cells/10(5) T cells) in patients with CVID compared with healthy controls (100 iNKT cells/10(5) T cells) was observed (P < .0001). Two cohorts could be discerned within the CVID group: group 1 with an abnormal number of iNKT cells (n = 28) and group 2 with a normal number of iNKT cells (n = 8). This segregation coassociated with the proliferative capacity of iNKT cells between the 2 groups. However, differences in the function of iNKT cells were noted in group 2, in which an increase in IFN-γ (P = .0016) and a decrease in IL-17 (P = .0002) production was observed between patients with CVID and controls. Finally, a significant association was seen between the number of iNKT cells and the percentage of class-switched memory B cells and propensity to lymphoproliferation (P = .002) in patients with CVID., Conclusion: iNKT cells are deficient and/or functionally impaired in most of the patients with CVID., (Copyright © 2014 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

Objectives: We aimed to examine the characteristics of deep venous flow in the leg in a cast and the effects of a wearable neuromuscular stimulator (geko; FirstKind Ltd) and also to explore the participants' tolerance of the stimulator., Methods: This is an open-label physiological study on ten healthy volunteers. Duplex ultrasonography of the superficial femoral vein measured normal flow and cross-sectional area in the standing and supine positions (with the lower limb initially horizontal and then elevated). Flow measurements were repeated during activation of the geko stimulator placed over the peroneal nerve. The process was repeated after the application of a below-knee cast. Participants evaluated discomfort using a questionnaire (verbal rating score) and a scoring index (visual analogue scale)., Results: The geko device was effective in significantly increasing venous blood flow in the lower limb both with a plaster cast (mean difference 11.5 cm/sec(-1); p = 0.001 to 0.13) and without a plaster cast (mean difference 7.7 cm/sec(-1); p = 0.001 to 0.75). Posture also had a significant effect on peak venous blood flow when the cast was on and the geko inactive (p = 0.003 to 0.69), although these differences were less pronounced than the effect of the geko (mean difference 3.1 cm/sec(-1) (-6.5 to 10)). The geko device was well tolerated, with participants generally reporting only mild discomfort using the device., Conclusion: The geko device increases venous blood flow in the lower limb, offering a potential mechanical thromboprolylaxis for patients in a cast. Cite this article: Bone Joint Res 2013;2:179-85.

Objective: Evidence for effective management of shoulder impingement is limited. The present study aimed to quantify the clinical, neurophysiological, and biomechanical effects of a scapular motor control retraining for young individuals with shoulder impingement signs., Method: Sixteen adults with shoulder impingement signs (mean age 22 ± 1.6 years) underwent the intervention and 16 healthy participants (24.8 ± 3.1years) provided reference data. Shoulder function and pain were assessed using the Shoulder Pain and Disability Index (SPADI) and other questionnaires. Electromyography (EMG) and 3-dimensional motion analysis was used to record muscle activation and kinematic data during arm elevation to 90° and lowering in 3 planes. Patients were assessed pre and post a 10-week motor control based intervention, utilizing scapular orientation retraining., Results: Pre-intervention, patients reported pain and reduced function compared to the healthy participants (SPADI in patients 20 ± 9.2; healthy 0 ± 0). Post-intervention, the SPADI scores reduced significantly (P < .001) by a mean of 10 points (±4). EMG showed delayed onset and early termination of serratus anterior and lower trapezius muscle activity pre-intervention, which improved significantly post-intervention (P < .05). Pre-intervention, patients exhibited on average 4.6-7.4° less posterior tilt, which was significantly lower in 2 arm elevation planes (P < .05) than healthy participants. Post-intervention, upward rotation and posterior tilt increased significantly (P < .05) during 2 arm movements, approaching the healthy values., Conclusion: A 10-week motor control intervention for shoulder impingement increased function and reduced pain. Recovery mechanisms were indicated by changes in muscle recruitment and scapular kinematics. The efficacy of the intervention requires further examined in a randomized control trial., (Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.)

The understanding of the genetic and immunological basis of human periodic fever syndromes, in particular cryopyrin-associated periodic syndromes (CAPS), has led to important new insights into the pathogenesis of monogenic and complex interleukin-1beta-associated autoinflammatory diseases. Currently the focus of attention is on the nucleotide-binding oligomerization domain (NOD)-like receptors (NLR), which take part in the regulation of the synthesis and maturation of cytokines in the IL-1 families, NOD-signalosomes and inflammasomes.

Inhibitory anti-muscarinic receptor type 3 (M3R) antibodies may contribute to the pathogenesis of Sjögren's syndrome (SS), and putative anti-M3R blocking antibodies in intravenous immunoglobulin (IVIg) have been suggested as a rationale for treatment with IVIg. We investigated the presence of subtype-specific anti-MR autoantibodies in healthy donor and SS sera using MR-transfected whole-cell binding assays as well as M1R and M3R peptide ELISAs. Control antibodies against the second extracellular loop of the M3R, a suggested target epitope, were induced in rabbits and found to be cross-reactive on the peptides M3R and M1R. The rabbit antibodies had neither an agonistic nor an antagonistic effect on M3R-dependent ERK1/2 signalling. Only one primary SS (out of 5 primary SS, 2 secondary SS and 5 control sera) reacted strongly with M3R transfected cells. The same SS serum also reacted strongly with M1R and M2R transfectants, as well as M1R and two different M3R peptides. Strong binding to M1R and low-level activities against M3R peptides were observed both in SS and control sera. IVIg showed a strong reactivity against all three peptides, especially M1R. Our results indicate that certain SS individuals may have antibodies against M1R, M2R and M3R. Our results also suggest that neither the linear M3R peptide nor M3R transfectants represent suitable tools for discrimination of pathogenic from natural autoantibodies in SS.

Lupus erythematosus profundus or lupus panniculitis is a rare clinical variant of lupus erythematosus, which involves the deep dermis and subcutaneous fat. Diagnosis may be difficult in cases with isolated involvement. Further manifestations of lupus erythematosus may thus be essential for diagnosis, which depends on the clinical picture, histopathology and a positive lesional lupus band test. We report a severe, mutilating case of lupus panniculitis, which responded well to thalidomide.

Objective: To analyse the performance of a new M. tuberculosis-specific interferon gamma (IFNgamma) assay in patients with chronic inflammatory diseases who receive immunosuppressive drugs, including tumour necrosis factor alpha (TNFalpha) inhibitors., Methods: Cellular immune responses to the M. tuberculosis-specific antigens ESAT-6, CFP-10, TB7.7 were prospectively studied in 142 consecutive patients treated for inflammatory rheumatic conditions. Results were compared with tuberculin skin tests (TSTs). Association of both tests with risk factors for latent M. tuberculosis infection (LTBI) and BCG vaccination were determined and the influence of TNFalpha inhibitors, corticosteroids, and disease modifying antirheumatic drugs (DMARDs) on antigen-specific and mitogen-induced IFNgamma secretion was analysed., Results: 126/142 (89%) patients received immunosuppressive therapy. The IFNgamma assay was more closely associated with the presence of risk factors (odds ratio (OR) = 23.8 (95% CI 5.14 to 110) vs OR = 2.77 (1.22 to 6.27), respectively; p = 0.009), but less associated with BCG vaccination than the TST (OR = 0.47 (95% CI 0.15 to 1.47) vs OR = 2.44 (0.74 to (8.01), respectively; p = 0.025). Agreement between the IFNgamma assay and TST results was low (kappa = 0.17; 95% CI 0.02 to 0.32). The odds for a positive IFNgamma assay strongly increased with increasing prognostic relevance of LTBI risk factors. Neither corticosteroids nor conventional DMARDs significantly affected IFNgamma responses, but the odds for a positive IFNgamma assay were decreased in patients treated with TNFalpha inhibitors (OR = 0.21 (95% CI 0.07 to 0.63), respectively; p = 0.006)., Conclusions: These results demonstrate that the performance of the M. tuberculosis antigen-specific IFNgamma ELISA is better than the classic TST for detection of LTBI in patients receiving immunosuppressive therapy for treatment of systemic autoimmune disorders.

Understanding the protective mechanism in the liver induced by recombinant vaccines against the pre-erythrocytic stages of malaria is important for vaccine development. Most studies in mice have focused on splenic and peripheral blood T cells and identified gamma interferon (IFN-gamma)-producing CD8+ T cells as correlates of protection, which can be induced by prime-boost vaccination with recombinant poxviruses. Invariant natural killer T (Valpha14iNKT) cells can also protect against liver stage malaria, when activated, and are abundant in the liver. Since poxviruses have nonspecific immunomodulating effects, which are incompletely understood, we investigated whether recombinant poxviruses affect the protective properties of hepatic Valpha14iNKT cells and thus vaccine efficacy. We show that intradermal vaccination with recombinant poxviruses activated Valpha14iNKT cells and NK cells in the livers of BALB/c mice while inducing IFN-gamma- and tumor necrosis factor alpha (TNF-alpha)-producing pre-erythrocytic stage antigen-specific CD8+ T cells. Greater numbers of hepatic Valpha14iNKT cells secreted interleukin-4 than IFN-gamma. Vaccinated Valpha14iNKT-cell-deficient mice had lower, but still protective levels of hepatic and splenic IFN-gamma+ and TNF-alpha+ CD8+ T cells and better protection rates later after challenge with Plasmodium berghei sporozoites. Therefore, vaccine-activated hepatic Valpha14iNKT cells help in generating specific T cells but are not required for protection induced by recombinant poxviruses. Furthermore, double-positive INF-gamma+/TNF-alpha+ CD8+ T cells were enriched in protected livers, suggesting that cells expressing both of these cytokines may be most relevant for protection.

The killing of natural killer (NK) cells is regulated by activating and inhibitory NK receptors that recognize mainly class I major histocompatibility complex (MHC) proteins. In transporter associated with antigen processing (TAP2)-deficient patients, killing of autologous cells by NK cells is therefore expected. However, none of the TAP2-deficient patients studied so far have suffered from immediate NK-mediated autoimmune manifestations. We have previously demonstrated the existence of a novel class I MHC-independent inhibitory mechanism of NK cell cytotoxicity mediated by the homophilic carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) interactions. Here, we identified 3 new siblings suffering from TAP2 deficiency. NK cells derived from these patients express unusually high levels of the various killer cell inhibitory receptors (KIRs) and the CEACAM1 protein. Importantly, the patients' NK cells use the CEACAM1 protein to inhibit the killing of tumor and autologous cells. Finally, we show that the function of the main NK lysis receptor, NKp46, is impaired in these patients. These results indicate that NK cells in TAP2-deficient patients have developed unique mechanisms to reduce NK killing activity and to compensate for the lack of class I MHC-mediated inhibition. These mechanisms prevent the attack of self-cells by the autologous NK cells and explain why TAP2-deficient patients do not suffer from autoimmune manifestations in early stages of life.

We have identified an HLA-A2-restricted CD8(+) T-cell epitope, FLYALALLL, in the Epstein-Barr virus (EBV) latent membrane protein 2 (LMP2), an important target antigen in the context of EBV-associated malignancies. This epitope is TAP independent, like other hydrophobic LMP2-derived epitopes, but uniquely is dependent upon the immunoproteasome for its generation.

Natural killer T (NKT) cells are thought to be involved in innate responses against infection. We investigated one specific type of NKT cell, Valpha24/Vbeta11 double positive, in hepatitis C virus (HCV) infection. Lower frequencies of this population were detected in the blood of HCV PCR-positive patients than in controls. Unlike Valpha24/Vbeta11 NKT cells found in blood, those in the liver appeared to be recently activated.

CD1 molecules are specialized in presenting lipids to T lymphocytes, but identification and isolation of CD1-restricted lipid specific T cells has been hampered by the lack of reliable and sensitive techniques. We here report the construction of CD1d-glycolipid tetramers from fully denatured human CD1d molecules by using the technique of oxidative refolding chromatography. We demonstrate that chaperone- and foldase-assisted refolding of denatured CD1d molecules and beta(2)-microglobulin in the presence of synthetic lipids is a rapid method for the generation of functional and specific CD1d tetramers, which unlike previously published protocols ensures isolation of CD1d tetramers loaded with a single lipid species. The use of human CD1d-alpha-galactosylceramide tetramers for ex vivo staining of peripheral blood lymphocytes and intrahepatic T cells from patients with viral liver cirrhosis allowed for the first time simultaneous analysis of frequency and specificity of natural killer T cells in human clinical samples. Application of this protocol to other members of the CD1 family will provide powerful tools to investigate lipid-specific T cell immune responses in health and in disease.

The nonclassical major histocompatibility complex (MHC) class I molecule HLA-E inhibits natural killer (NK) cell-mediated lysis by interacting with CD94/NKG2A receptors. Surface expression of HLA-E depends on binding of conserved peptides derived from MHC class I molecules. The same peptide is present in the leader sequence of the human cytomegalovirus (HCMV) glycoprotein UL40 (gpUL40). It is shown that, independently of the transporter associated with antigen processing, gpUL40 can up-regulate expression of HLA-E, which protects targets from NK cell lysis. While classical MHC class I molecules are down-regulated, HLA-E is up-regulated by HCMV. Induction of HLA-E surface expression by gpUL40 may represent an escape route for HCMV.