OncoQuick significantly reduced the co-enriched number of MNCs, with a high tumor cell recovery rate. Processing blood from tumor patients with OncoQuick increased the chance of detecting circulating tumor cells.

Human lymphocyte antigen (HLA) associations are recognized for many autoimmune diseases, but the mechanisms are not clear. Goodpasture's disease provides a unique opportunity to investigate possible mechanisms because strong HLA associations are known, the autoantigen is well defined, and major antigen-derived peptides presented bound to HLA molecules have been identified. Therefore, it may be possible to directly analyze interactions between the antigen and HLA molecules associated with the disease, and to examine influences on antigen presentation to T cells. Towards this goal, we present a detailed analysis of HLA associations with the disease and examine molecular mechanisms that could account for them.

Class II molecules are believed to influence immune responses by selectively binding antigen-derived peptides for recognition by T cells. In Goodpasture's (antiglomerular basement membrane) disease, autoimmunity to the NC1 domain of the ␣3-chain of type IV collagen (␣3(IV)NC1) is strongly associated with HLA-DR15. We have examined the influence of the peptide binding preferences of DR15 molecules on the selection of ␣3(IV)NC1-derived peptides displayed bound to DR15 molecules on the surface of ␣3(IV)NC1-pulsed DR15-homozygous Epstein-Barr virus-transformed human B cells. The preferences of DR15 molecules were investigated using a panel of 24 overlapping peptides spanning the sequence of ␣3(IV)NC1. The ␣3(IV)NC1-derived peptides selected for display to T cells were determined by biochemical analysis as reported previously (Phelps, R. G., Turner, A. N., and Rees, A. J. (1996) J. Biol. Chem. 271, 18549 -18553).Three nested sets of naturally presented ␣3(IV)NC1 peptides were detectable bound to DR15 molecules. Peptides representative of each nested set bound to DR15 molecules, but almost two-thirds of the ␣3(IV)NC1 peptides studied had as good or better DR15 affinity than those identified as naturally processed. Thus ␣3(IV)NC1 presentation to T cells is determined more by "processing factors" than by the preferences of relatively indiscriminate DR15 molecules. The results have important implications for the use of class II peptide binding data to aid identification of potential T cell epitopes, especially for antigens which, like ␣3(IV)NC1, contain many sequences able to bind class II molecules. Antigen presenting cells (APC)1 potentially exert a profound influence on immune responses, including those to self antigens, because they regulate the way T cells recognize antigens. CD4 T cells recognize antigens in the form of processed peptides presented bound to MHC class II molecules on the surface of class II positive APC types (1, 2). These include cells important in the initiation of immune responses, such as dendritic cells, B cells, and macrophages, and cells important in regulating the T cell repertoire and self-tolerance, such as thymic epithelia. How APC select antigen-derived peptides for display to T cells therefore not only constrains the peptide specificity of responding T cells, but also influences the repertoire of T cells available to mount immune responses. Furthermore, the way APC present antigens may determine the immunodominant T cell response, which at least for some exogenous antigens is directed at the antigen-derived peptide displayed at the highest level (3). There is therefore great interest in understanding how APC generate antigen-derived peptides and make a selection for display to T cells, both as an approach to identifying T cell epitopes for specific immune modulation and toward understanding the basic biology of immune responses.APC, like many cell types, internalize extracellular proteins into their endosomal/lysosomal pathway where denaturing (low pH and reducing) conditions promote th...

Background: Autoimmune disorders including nephropathies have been reported more frequently in alemtuzumab-treated multiple sclerosis (MS) patients than in the general population. Objective: Describe instances of autoimmune nephropathy in alemtuzumab-treated MS patients. Methods: Cases were identified from safety monitoring within the alemtuzumab relapsing-remitting multiple sclerosis (RRMS) clinical development program (CDP) or post-marketing, or following off-label use. Results: As of 16 June 2017, 16 autoimmune nephropathies have occurred following alemtuzumab treatment for MS. The incidence of autoimmune nephropathies was 0.34% within the CDP (5/1485 patients). The five CDP cases (one of anti-glomerular basement membrane (anti-GBM) disease, two of membranous glomerulonephropathy, and two of serum anti-GBM antibody without typical anti-GBM disease) were identified early, responded to conventional therapy (where needed), and had favorable outcomes. Three of 11 cases outside the CDP occurred following off-label alemtuzumab use prior to approval for RRMS and were all anti-GBM disease. Diagnosis was delayed in one of these three cases and another did not receive appropriate treatment; all three cases resulted in end-stage renal failure. All anti-GBM disease cases with documented urinalysis demonstrated prior microscopic hematuria. Conclusion: Close monitoring of alemtuzumab-treated MS patients facilitates diagnosis and treatment early in the nephropathy course when preservation of renal function is more likely.

BackgroundOnline access to all or part of their health records is widely demanded by patients and, where provided in form of patient portals, has been substantially used by at least subgroups of patients, particularly those with chronic disease. However, little is reported regarding the longer-term patient use of patient-accessible electronic health record services, which is important in allocating resources. Renal PatientView (RPV) is an established system that gives patients with chronic kidney disease access to live test results and information about their condition and treatment. It is available in most UK renal units with up to 75% of particular patient groups registered in some centers. We have analyzed patient use out to 4 years and investigated factors associated with more persistent use.ObjectiveOur aim was to investigate RPV use by patients over time from initial registration in order to understand which patients choose to access RPV and the endurance of its appeal for different patient groups.MethodsWe analyzed an anonymized extract of the database underlying RPV containing information on patient registration and events including patient access and the arrival of new blood test results or letters that patients might wish to view.ResultsAt the time of the extract, there were 11,352 patients registered on RPV for 0-42 months (median 17). More than half of registrants became persistent users, logging in a median of 2.0 times each month over post-registration intervals of up to 42 months (median 18.9). Provision of assistance with first logon was strongly associated with becoming a persistent user, even at 3 years. Logons by persistent users occurred around the time of consultations/tests, strongly suggestive of patient engagement. While indices indicative of greater deprivation were the strongest determinants of non-participation, they had negligible influence on drop-out rates among established users.ConclusionsIn this mature patient portal system, a large proportion of patients made regular use of their online health records over protracted periods. The patterns and timing of use indicate strong patient interest in detailed information such as recent test results and clinic letters. Supporting patients through the first steps of establishing access to their online records is associated with much higher rates of long-term use of RPV and likely would increase use of other electronic health records provided for patients with chronic disease.

Autoreactive T cells in patients with Goodpasture's disease are specific for epitopes in the Goodpasture antigen (the NC1 domain of the ␣3 chain of type IV collagen) that are rapidly destroyed during antigen processing to a degree that diminishes their presentation to T cells. We hypothesized that patients' autoreactive T cells exist because antigen processing prevents presentation of the self-epitopes they recognize, circumventing specific tolerance mechanisms. We predicted that autoreactive T cells specific for these peptides should also exist in healthy individuals, albeit at low frequency and in an unprimed state. We obtained blood from healthy unrelated donors and, using a panel of 45 ␣3(IV)NC1 peptides, identified ␣3(IV)NC1-specific T cells in all donors. Thirty-six of 45 peptides elicited a proliferative T cell response from at least one subject, and 6 of the peptides evoked a response in Ͼ50% of the individuals. This consistency was not caused by selectivity of HLA class II molecules because the donors expressed a diversity of HLA antigens, but was largely a result of the substrate-specificity of the endosomal proteases Cathepsin D and E. There was a significant correlation between high susceptibility to Cathepsin D digestion and the capacity to stimulate primary T cell responses (P ϭ 0.00006). In summary, healthy individuals have low frequencies of unstimulated ␣3(IV)NC1-reactive T cells with similar specificities to the autoreactive T cells found in patients with Goodpasture disease. In both cases, existence of the ␣3(IV)NC1-reactive T cells can be accounted for by destructive processing.

The results demonstrate that alpha3(IV)NC1 is expressed in the human thymus, and therefore should be available for induction of alpha3(IV)NC1-specific tolerance. This observation has the important implication that patients' alpha3(IV)NC1-specific, autoreactive T cells are more likely to recognize cryptic epitopes that are not adequately presented by thymic antigen-presenting cells (APC) than the major antigen-derived epitopes generally identified by conventional approaches.

Goodpasture's disease provides an opportunity to analyse molecular mechanisms that may underlie MHC class II associations with autoimmune disease because it is caused by autoimmunity to a defined antigen [the 230 amino acid NC1 domain of the alpha3 chain of type IV collagen (alpha3(IV)NC1)] and has strong HLA class II associations. We compared the alpha3(IV)NC1 peptide binding of class II molecules with strong positive (DR15) and dominant negative (DR7/1) associations using an inhibition binding assay and short synthetic peptides spanning the sequence of alpha3(IV)NC1. DR15 in general bound the peptides with low affinity (three of 23 < 100 nM) compared to DR1 and DR7 (12 and 10 < 100 nM respectively), and no peptide bound DR15 with much higher affinity (>10-fold) than both DR1 and DR7. Thus DR15 molecules are unlikely to increase susceptibility to Goodpasture's disease by presenting a particular alpha3(IV)NC1-derived peptide uniquely well and DR1/7 are unlikely to protect by their inability to present particular peptides. However DR1/7 could protect by capturing alpha3(IV)NC1 peptides and preventing their display bound to DR15; the binding data suggest that all the major (biochemically detectable) alpha3(IV)NC1 peptides presented bound to DR15 by DR15 homozygous antigen-presenting cells (APC) would bind preferentially to DR1/7 in DR15, 1/7 heterozygote APC.