Interferon-gamma release assays (for example the QuantiFERON-TB test) are also used to test for TB. These tests are useful for evaluation of LTBI in BCG-vaccinated individuals, including almost

all Japanese. Anti-tuberculosis agents are administered to treat LTBI in kidney transplant patients. Currie et al. performed a meta-analysis of the outcomes of INH prophylaxis in kidney transplant patients with LTBI. Of four tested randomized control trials, INH significantly reduced the level of active TB infections (RR, 0.31; 95% CI, 0.19–0.51) but not hepatitis (RR, 1.22; 95% CI, 0.91–1.65).[3] The European Guidelines suggest that INH treatment for 9 months, or RFP treatment for 6 months, is helpful in such situations.[4] Treatment of active TB infections in kidney transplant recipients involves prescription of INH, RFP, EB and PZA for

2 months; and INH and RFP are usually continued for a further 4 months. Co-prescription of CNI Selleckchem Paclitaxel and RFP is a critical issue in kidney transplant patients. RFP decreases the serum CNI level by inducing hepatic cytochrome P 450, and inadequate immunosuppression may trigger acute rejection. The CNI dose should be increased two- or threefold during treatment with RFP.[5] Nevertheless, the rate of acute rejection in transplant recipients treated with RFP is significantly higher than in those not prescribed RFP (35% and 19%, respectively).[6] This may reflect the fact that the bioavailability of CNI varies. Thus, several authors have PLX4032 sought to eliminate RFP from the antituberculosis drug cocktail given to kidney transplant

recipients. Yoon et al. used a quinolone-based regimen to treat tuberculosis in such patients.[7] Quinolones are commonly used as second-line treatments of TB in patients with multidrug-resistant infections or who respond adversely to first-line drugs. In the cited report, a quinolone-based regimen (n = 18, INH + levofloxacin + EB + PZA) was as effective as an RFP-based regimen (n = 91, INH + RFP + EB + PZA) when used to eliminate TB, but the number of acute rejections in the RFP group was fourfold higher than in the QNL group even though the CNI dose was increased two- to Idoxuridine fivefold in the former group to maintain stable trough CNI levels. CYP3A4 is less likely to be induced by rifabutin than RFP. The protease inhibitors commonly used to treat HIV strongly induce CYP3A4, and a rifabutin-based regimen is usually prescribed to treat TB in HIV patients receiving anti-HIV agents. Lopez et al. reported the case of a 44-year-old Hispanic woman prescribed a rifabutin- rather than an RFP-based regimen to treat TB, because her serum CNI level had not entered the targeted trough range (from below) even though the CNI dose had been increased almost fivefold. The serum CNI level increased rapidly after the switch to rifabutin and was well maintained as the CNI dose was decreased gradually.

Since 2007, GWAS have increasingly been applied to pharmacogenetics to identify loci that affect see more either drug response or susceptibility to adverse drug reactions. These studies have shown the value of this approach in many fields [18, 78-83]. However, there are limitations in conducting GWAS in pharmacogenetics. First, the variation in drug response is likely to be multifactorial, with many genes working in conjunction with the environment. Second, current GWAS are targeted at elucidating the independent effects of single genes, and may miss interactive or synergistic effects. Furthermore, the challenges in performing adequate replication studies have to be considered for

GWAS in pharmacogenetics, particularly INCB024360 when evaluating small cohorts, such as nonresponders to UDCA in PBC. UDCA, which is currently the only available drug in PBC, is thought to work on the downstream events of the pathogenic mechanism of the disease, through reducing the toxicity of bile and reducing bile duct cell apoptosis [84]. There are ongoing studies, focused on exploring, with a GWA approach, the mechanism(s) beyond the lack of biochemical response to UDCA treatment. A major aim of this ongoing project is to identify potential sites for therapeutic intervention in nonresponsive patients.

New therapeutic targets that may be highlighted by GWAS, as applied to pharmacogenetics, can be localized either in the upstream or downstream processes of PBC pathogenesis; from the mechanisms that lead to loss of tolerance to the fibrotic phase secondary to cholestasis. Furthermore, improved knowledge of the genetic basis of the lack of response to UDCA will allow to identify

nonresponders at an early stage and to select them for next-generation drug trials. Attempting to predict the onset and progression of disease is one of the cornerstones of epidemiology. GWAS show significant potential to identify molecular factors that enable patient stratification and might prove useful in personalized medicine. Accurate risk prediction can enable targeted preventative treatments or more intensive follow-up, particularly for patients at high risk of progression. The success of recent GWAS has rapidly changed the outlook next for genetic risk prediction. These studies have unlocked thousands of clearly validated genetic associations to complex diseases, but their generally weak effects have left their predictive value and clinical utility subject to hot debate. GWAS data might find ready application in risk prediction in PBC in those patients identified at an early stage of the disease. Risk stratification at an early stage may be important from the perspective of developing treatments that either prevent disease entirely or that improve the outcome when instituted before biliary fibrosis and cirrhosis develop.

Examination revealed both proximal and distal

muscle weakness in 17 patients, of whom 10 presented with more proximal weakness, five with more distal weakness and two with equal proximal and distal weakness. There were only two patients with isolated proximal weakness and one patient with isolated distal weakness. There were eight patients with muscle atrophy, one patient with bilateral gynaecomastia and one patient with spine ankylosis. All 25 living Selleck SCH772984 patients were examined by electrocardiogram and echocardiography at the time of diagnosis. Twenty-four patients (24/25, 96%) presented with miscellaneous cardiac arrhythmia, including 15 patients (15/24, 60%) with complete atrial ventricular block, five patients small molecule library screening (5/24, 20.8%) with complete right or left bundle branch block, four patients (4/24, 16.7%) with premature ventricular beats, two patients (2/24, 8.3%) with atrial fibrillation, one patient (1/24, 4.2%) with a junctional escape beat and one patient (1/24, 4.2%) with supraventricular tachycardia. However, only six patients had abnormalities of cardiac function and morphology on examination by echocardiography,

including dilated cardiomyopathy in one patient, hypertrophic cardiomyopathy in one patient, restrictive cardiomyopathy in two patients, and atrium dilation in two patients. The serum creatine kinase level Glycogen branching enzyme was normal in five patients, elevated to 280–1760 IU/l in 12 patients, and not determined in eight patients. Electromyograms were performed in nine patients. Myogenic patterns were recorded in eight patients, and myogenic with neurogenic changes in one patient.

In five cases (index cases of family 1, family 4, family 5, one affected individual of family 4 and sporadic case 2), muscle pathology showed a dystrophy-like pattern with great variation in fibre diameters ranging from 10 to 160 µm, significant internal nuclei, an increase in split fibres, and significant connective tissue proliferation in the perimysium. Necrotic fibres and regenerating fibres were uncommon. COX-negative fibres were observed in two cases. Sparse endomysial inflammatory cells appeared in three cases. Four other patients (one affected individual of family 1, index cases of family 2 and 3, as well as sporadic case 1) exhibited a myopathy-like pattern with fibre diameters ranging from 20 to 90 µm, a few internal nuclei, and no connective tissue proliferation (Table 2 and Supporting Information). The abnormal structures were best observed by MGT staining in the affected fibres (Figure 1A,B). The abnormal fibres contained one or more of the following features: (i) Abnormal areas with blue amorphous materials.

However, OVA-pulsed viable DC that had taken up apopotic DC failed to induce OVA-specific T-cell proliferation HSP inhibitor (Fig. 5F). These results indicate that upon uptake of apoptotic DC but not necrotic DC, viable DC are refractory to LPS-induced maturation. As viable DC acquired a tolerogenic phenotype upon apoptotic DC uptake, we then assessed the ability of viable DC to induce Treg differentiation upon apoptotic DC uptake. Culture of naïve CD4+CD25– OT-II T cells with OVA-pulsed viable DC resulted in approximately 4–5% of naïve T

cells differentiating into Foxp3+ Treg, which increased to approximately 23–24% upon culture with OVA-pulsed MG-132 solubility dmso viable DC that had taken up apoptotic DC. In contrast, culture of naïve CD4+CD25– T cells with OVA-pulsed viable DC that had taken up necrotic DC only resulted in approximately 5–6% Foxp3+ Treg (Fig. 6A and B). The increase in the proportion of Foxp3+ Treg was not paralleled by an increase in the absolute T-cell count, indicating that it was likely the induced expression of Foxp3 and not expansion, which mediated the observed increase in the proportion of Foxp3+ Treg among T cells cultured with OVA-pulsed viable DC that had taken up apoptotic DC (data not shown). In order to test whether the induction of Foxp3+ Treg

was induced specifically upon uptake of apoptotic DC by viable immature DC and not by uptake of other types of apoptotic cells, we looked at the effects of apoptotic splenocyte uptake on the ability of viable

DC to induce Foxp3+ Treg. Results indicate that the uptake of apoptotic splenocytes did not enhance the ability of viable DC to induce Treg, as only 7–8% of naïve T cells differentiated into Foxp3+ Treg, which was similar to the control group. Furthermore, we also assessed the ability of in vitro-generated Foxp3+ Treg to suppress T-cell proliferation. Bcl-w Our findings identify that the CD4+CD25+ T-cell subset only from the co-culture of naïve T cells and OVA-pulsed viable DC that had taken up apoptotic DC, was in fact enriched for suppressor T cells, as they were able to inhibit T-cell proliferation in a dose-dependent manner (Fig. 6C). Overall, these results indicate that it was specifically the uptake of apoptotic DC which was primarily responsible for the induction of Foxp3+ Treg by viable DC. Next, we wanted to assess whether the ability to induce Foxp3+ Treg by viable DC upon apoptotic DC uptake dependent on interaction with naïve T cells or soluble factors. This was tested by separating T cells from DC using a transwell plate followed by an assessment of Foxp3+ Treg induction.

This is consistent with our findings in the study. The pooled incidence for AKI in the statin

group was higher than the nonstatin group (6.13% vs. 4.28%). The effect of preoperative statin on postoperative AKI was insignificant in pooled crude analysis (pooled OR, 0.98; 95% CI 0.82–1.18, I2 = 87.7%), but turned significant in pooled adjusted (pooled OR, 0.86; 95% CI 0.78–0.95, I2 = 69.4%) and PSM analyses (pooled OR, 0.83; 95% CI 0.75–0.92, I2 = 67.1%). A similar condition presented in the analysis of preoperative statin on postoperative AKI requiring RRT. The pooled crude analysis showed a paradoxical harmful effect of statin therapy (pooled OR, 1.46; 95% CI 1.31–1.62, I2 = 48.4%), while the adjusted (pooled OR, 0. 81; 95% CI 0.72–0.91, I2 = 0.0%) this website and PSM analyses (pooled OR, 0.81; 95% CI 0.72–0.92, I2 = 0.0%) showed significant protective effects of statin therapy. The different results of crude versus adjusted and PSM analyses reflected the importance of the methodological quality

of studies. The subgroup analysis of the five RCTs showed a non-significant protective effect on postoperative AKI (pooled OR, 0.49; 95% CI 0.22–1.09, I2 = 0.0%). There were several possible explanations for the null effect of these studies of the theoretically highest methodological quality. First, the pooled sample size was only 467 and the total events of AKI were 19 (8%) and 29(12.5%). The small sample size may be underpowered to detect the protective effect of statin. Second, postoperative AKI was prespecified as a primary endpoint in only one out of the NVP-AUY922 order five RCTs. Other studies

reported postoperative AKI as a secondary outcome or merely reported the number of events without prespecified outcome definition. The accuracy of the record might be questioned. Third, the definition for postoperative AKI differs a lot in these five studies. In two studies,[25, 27] no clear definition for postoperative AKI was provided. Liakopoulos OJ et al. had conducted a systemic review and meta-analysis based on RCTs.[21] They ifoxetine included four RCTs[24-27] and a total of 367 participants were analyzed for the effect of preoperative statin on postoperative renal outcome. The assessed renal outcome, renal failure, had an incidence of 3.2% in the statin group and 7.1% in the control group. In correspondence to our result, they reported a non-significant protective effect (pooled OR, 0.41; 95% CI 0.15–1.12, P = 0.08) from pooled analysis with a fixed effect model. The pooled crude incidence of postoperative AKI and postoperative AKI requiring RRT were 4.89% and 0.94%, respectively (Table 2). These results were consistent with previous report for incidence of postoperative AKI and AKI requiring RRT,[1-4] which ranged 1–30% and 0.7–1.4%, respectively.

aeruginosa and S. aureus grown in a flow-chamber system. We demonstrated how adaptive mutations in regulator genes of P. aeruginosa affect interactions between P. aeruginosa and S. aureus in co-culture biofilms. Pseudomonas aeruginosa

wild-type PAO1 (Holloway & Morgan, 1986), P. aeruginosa mucA mutant (Hentzer et al., 2001), Selleckchem Alpelisib P. aeruginosa rpoN mutant (Webb et al., 2003), P. aeruginosa pilA mutant (Klausen et al., 2003b), P. aeruginosa pilH mutant (Barken et al., 2008), P. aeruginosa pqsA mutant (D’Argenio et al., 2002), S. aureus MN8 (Yarwood et al., 2004), S. aureus ISP479 (Toledo-Arana et al., 2005) and S. aureus 15981 (Toledo-Arana et al., 2005) were kindly provided by the cited authors and used in the present study. The pDA2 plasmid (An et al., 2006) was used check details to complement the pilA mutant. Fluorescence-tagged strains were constructed by the insertion of a mini-Tn7-eGFP-Gmr cassette as described (Koch et al., 2001; Klausen et al., 2003b). Escherichia coli strains MT102 and DH5α were used for standard DNA manipulations. Luria–Bertani medium (Bertani, 1951) was used to cultivate E. coli strains. A modified FAB medium (Qin et al., 2007) supplemented with 0.3 mM glucose and 3% of Tryptic Soy Broth (TSB, BD Diagnostics) was used for biofilm cultivation. Selective media were supplemented with ampicillin (100 mg L−1), gentamicin (60 mg L−1) or carbenicillin

(200 mg L−1). Biofilms were grown in flow chambers

with individual channel dimensions of 1 × 4 × 40 mm at 37 °C. The flow system was assembled and prepared as described previously (Sternberg & Tolker-Nielsen, 2006). Overnight cultures of P. aeruginosa and S. aureus were diluted to an OD600 nm of 0.001. The flow chambers were inoculated by injecting 350 μL of monospecies diluted cultures or P. aeruginosa–S. aureus 1 : 1 mixed-species diluted cultures into each flow channel with a small syringe. After inoculation, flow channels were left without flow for 1 h, after which medium flow (0.2 mm s−1) was started using a Watson Marlow 205S peristaltic pump. For DNase I treatment, biofilm medium was supplemented with 20 μg mL−1 bovine DNase I (Sigma) from the beginning of cultivation. All microscopic observations and image acquisitions were performed using a Zeiss LSM 510 confocal laser scanning microscope (Carl Zeiss, Jena, Protirelin Germany) equipped with detectors and filter sets for monitoring of green and red fluorescence from general nucleic acid staining SYTO 9 (Invitrogen) and gram-positive specific staining hexidium iodide (Invitrogen) (Mason et al., 1998), respectively. BacLite Live/Dead viability stain (Molecular Probes, Eugene, OR) was used to visualize dead and live cells in co-culture biofilms. Images were obtained using a × 40/1.3 objective. Simulated three-dimensional images and sections were generated using the imaris software package (Bitplane AG, Zürich, Switzerland).

In the present study, we investigated whether a Nogo66 receptor (NgR) vaccine, combined with neural stem cell (NSC) transplantation, could promote better functional recovery than when NgR vaccine or NSCs were used alone. Methods: Adult rats were immunized with NgR vaccine at 1 week after a contusive SCI at the thoracic level, and the NSCs, obtained from green fluorescent protein

transgenic rats, were transplanted into the injury site at 8 weeks post injury. The functional recovery of the animals under various treatments was evaluated by three independent behavioural tests, that is, Basso, Beattie and Bresnahan locomotor rating scale, footprint analysis and grid walking. Results: The combined therapy with NgR Trametinib price vaccination and NSC transplantation protected more ventral horn motor neurones in the injured spinal cord and greater functional recovery than when they were used alone. Furthermore,

NgR vaccination promoted migration of engrafted NSCs along the rostral-caudal axis of the injured spinal cords, and induced their differentiation into neurones and oligodendrocytes in vivo. Conclusions: The combination therapy of NgR vaccine and NSC transplantation this website exhibited significant advantages over any single therapy alone in this study. It may represent a potential new therapy for SCI. “
“Brain ischaemia and reperfusion produce alterations in the microenvironment of the parenchyma, including ATP depletion, ionic homeostasis alterations, inflammation, release of multiple cytokines and abnormal release of neurotransmitters. As a consequence, the induction of proliferation and migration of neural stem cells is redirected towards the peri-infarct region. The success of new neurorestorative treatments for damaged brain implies the need to describe with greater accuracy the mechanisms in charge of regulating adult neurogenesis, under both physiological and pathological conditions. Recent evidence demonstrates that many neurotransmitters, glutamate in particular, control the Thiamine-diphosphate kinase subventricular zone (SVZ), thus being part

of the complex signal network that exerts a remarkable influence on the production of new neurones. Neurotransmitters provide a link between brain activity and SVZ neurogenesis. Therefore, a deeper knowledge of the role of neurotransmitters systems, such as glutamate and its transporters, in adult neurogenesis, may prove a valuable tool to be utilized as a neurorestorative therapy in this pathology. “
“Pilocytic astrocytomas (PAs) are characterized by an excellent prognosis although several factors of adverse outcome have been reported. The mitogen-activated protein kinase pathway plays a major role in their tumorigenesis. To report a series of 148 PAs in children to define clinicopathological and biological prognostic factors. Clinical data were collected from patient files and mail inquiry. Pathological specimens were centrally reviewed.

[8-12] Studies in vivo have also demonstrated a role in colitis and ileitis.[13-17] DR3 regulates immunity to certain bacteria,[18] viruses,[19] tumours[20] and intrinsically maintains NVP-BGJ398 order neurological function.[21] Research in humans has mirrored these findings, primarily showing that DR3 regulates

inflammation and immunity through controlling the development of effector T cells and differentiation of myeloid subsets,[22-30] but it may also have effects on other cell types such as neurons.[31] Local and systemic increases of its ligand are associated with multiple human inflammatory disorders.[32-35] In this respect, the designation ‘Death Receptor 3’ is a misnomer because many of the recognized functions of the gene are associated with cell expansion and differentiation, rather than death. Park et al.[1] clearly describe an increase in cell viability of tumour cell lines following exposure to natural killer (NK) cells when DR3 expression was knocked down; results consistent with DR3 acting to trigger cell death.

To my knowledge, this is the first functional demonstration of a pro-apoptotic role for DR3 in human tumour cell lines, but it is not unique as a general phenomenon. The original DR3 knockout mouse exhibited a defect in negative selection of thymocytes,[36] while DR3-dependent apoptosis Vildagliptin has been described in renal inflammation in vivo[37] and osteoblast cell lines in vitro.[38] Furthermore, a role in human cancer has been implied from the discovery that this website the DR3 gene is disrupted in ~ 40% of neuroblastomas.[39] It is in this context that clarification is useful on the nature of the DR3 ligand, as its identity is also complicated by a history of diverse nomenclature. Park et al.[1] mention two ligands in their references, Apo3L and TL1A, both of which are distinct tumour necrosis factor superfamily (TNFSF) members. Apo3L was originally named as the ligand for DR3 (i.e. Apo3)[40] and was also called TWEAK (TNFSF12). However,

follow-up studies could not confirm this[41] and indicated that TWEAK signalled in the absence of DR3.[42] A second receptor for TWEAK, Fn14 (TNFRSF12A), was then identified,[43] and TL1A (TNFSF15 and the full-length gene product of the vascular endothelial growth inhibitor, VEGI) was found to bind DR3.[44] All-encompassing work from Bossen et al.[45] involving flow cytometric binding assays between the majority of human and murine TNFSF:Fc proteins and cell lines transfected with TNFRSF members confirmed this, i.e. that TWEAK binds Fn14, whereas TL1A binds DR3 and there is minimal cross-reactivity, findings that have been borne out in later in vivo experiments using gene knockouts.

In addition, CD69 might act specifically on the Treg cell subset, directly suppressing the activity of effector T cells [56]. After MSC/CD4+CD25– co-cultures, we observed that SSc cells were able

to induce normally functioning Tregs from the T lymphocytes of HC and SSc patients. As Pritelivir CD69 expression by Tregs has been associated with the production of TGF-β [55], we analysed the surface expression of this molecule in induced Tregs. Interestingly, although the CD69 surface expression was decreased in circulating SSc Tregs, an increased expression of this molecule was observed in induced cells without differences between patients and controls. Consistent with this evidence, Rapamycin induced SSc Tregs showed a normal ability to inhibit immunoproliferation of CD4+ T cells. We observed an increase of TGF-β production in the supernatants of SSc–MSC co-cultures, and this

production was associated with an increase of TGF-β gene expression in the SSc–MSCs. During SSc, IL-6 and TGF-β are involved not only in immunoregulatory mechanisms but also in the pathogenesis of the fibrotic process, which is the main feature of the disease. Further experiments are ongoing in our laboratory in order to evaluate the role of these cytokines, produced by MSCs, on collagen production as well as on modulation of the myofibroblast phenotype. These cAMP findings might suggest that, during SSc, an adaptive cytokine profile with an increase in both TGF-β and IL-6 expression avoids senescence interfering with MSC activity, thus maintaining their role in inducing fully functional Tregs. In this work we did not investigate the immunosuppressive role of senescent SSc–MSCs on dendritic cell functions, already shown in other conditions. It is well known that these cells produce higher levels of IL-10 and

might contribute to the specific cytokine milieu in the disease [57]. Furthermore, recent reports showed that dendritic cells might express TGF-β and support fibrogenesis [58]. In this setting, the possible modulation of dendritic cells might offer a new future target for MSC therapeutic application. The in-vitro immunosuppressive activity of MSCs is mediated by direct interaction with lymphocytes at a MSC : PBMC ratio of 1:1 [59]. This raises a question: are these MSC : PBMC ratios achieved normally in vivo, when MSC are utilized clinically in the clinical setting? Indeed, according to the immunosuppression observed in vivo [60], relatively high numbers of MSC should be injected to obtain this effect. This may be of great relevance in planning the dose of MSC to administer. However, some difficulties in obtaining a sufficient number of MSCs for clinical purposes have been described previously [61].

A number of phenotypic similarities between JNK1−/− T cells and Tat-POSH-treated cells were also observed. Tat-POSH-treated T cells have defective CD25 expression and cell cycle entry. They make negligible amounts of IL-2 and showed no changes in granzyme B, in stark contrast to JNK2−/− CD8+ T cells [16, 17, 19]. The effector cytokine expression profile also more closely resembles JNK1−/− than JNK2−/− T cells [13, 16, 17,

44]. Interestingly, the disruption of the POSH/JIP-1 complex for the first 48 h of activation led to a defect in the program of differentiation that resulted in a persistent deficiency in the Veliparib supplier effector response even after the ability to disrupt the complex is lost. Remarkably, T cells activated in the presence of the inhibitor for only 2 days maintained their defect throughout an antitumor immune response in vivo. Furthermore, addition of the inhibitor 2 days poststimulation had no effect. Thus, the POSH-dependent commitment to IFN-γ is programed in the first 48 h. This suggests a role (direct or indirect) for the POSH/JIP-1 network in the transcriptional regulation of epigenetic modifications necessary for the early development of T-cell effector functions. Confirmation of selleck kinase inhibitor the programing defect

was evident from the decrease in the phosphorylation of c-Jun, defects in the induction of T-bet, Eomes, and reduced effector cytokine production. JNK1 induces the phosphorylation of c-Jun and leads to increases in the mRNA expression Lonafarnib of both

T-bet and Eomes [18, 42]. Conversely, JNK2 is a negative regulator of T-bet and Eomes mRNA expression [19]. Along these lines, the protein levels of Eomes were not induced above background in the presence of Tat-POSH. Intriguingly, protein expression of T-bet in CD8+ T cells was low early but recovered at later time points. Whether this is due to changes in the POSH/JIP-1 complex or other cause is not known. These data differ slightly from previous work where JNK1 deficiency had a greater impact on T-bet than Eomes [19]. Surprisingly, Perforin expression, which is defective in JNK1−/− CD8+ T cells [18], was only slightly affected by disruption of POSH/JIP-1 complex. This was also unexpected, as Eomes deficiency has been linked to the reduction of perforin mRNA expression [42]. The differences between these and earlier works may be attributed to the methods of quantification (mRNA versus protein) and relative stability of these two proteins. Alternatively, they suggest a role for JNK in expression of these effector molecules and transcription factors that does not involve the formation of the POSH/JIP-1 complex. Interestingly, the ability to disrupt the complex with Tat-POSH diminishes over time. This indicates that the composition or configuration of the POSH/JIP1 complex changes over the course of the immune response.