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Prolymphocytic leukaemias of B and T cell subtype are rare diseases. Despite recent advances in immunophenotyping and molecular cytogenetics, leading to a better understanding of the underlying cell biology of the prolymphocytic leukaemias, prognosis for these patients remains poor. Purine analogues and monoclonal antibodies have shown efficacy in B-cell prolymphocytic leukaemia although further studies are warranted. Monoclonal antibody therapy with alemtuzumab has significantly improved outcome in T-cell prolymphocytic leukaemia (T-PLL) but responses are still transient and further disease progression is inevitable. While allogeneic stem cell transplant is an attractive option, due to the older age group of T-PLL patients the morbidity and mortality associated with the procedure is significant. [ABSTRACT FROM AUTHOR]

To evaluate the clinical significance of CD21S expression of diffuse large B-cell lymphoma (DLBCL) tumour cells, we compared their clinical features, immunophenotype, response to therapy and outcome in relation to CD21S expression. Between 1987 and 1999, frozen sections from 240 DLBCL cases were examined for CD21S expression by immunohistochemical methods. CD21S expression was detected on the tumour cells of 87 (36%) cases. The median age of the CD21S+ DLBCL cases was 65 years (range: 17–84 years), the male–female ratio was 42:45, and they showed the following clinical features: Eastern Cooperative Oncology Group score >1 in 14%, lactate dehydrogenase greater than normal levels in 38%, extranodal sites >1 in 14%, stages III/IV disease at diagnosis in 29%, B symptoms in 17%, and a high/high–intermediate International Prognostic Index (IPI) in 23%. They also showed a better overall survival ( P = 0·00001, log-rank test) and a better complete remission rate ( P = 0·00004, chi-square test) than CD21S− DLBCL. Moreover, CD21S+ DLBCL showed a better survival than CD21S− DLBCL for both low/low–intermediate and high/high–intermediate risk categories of IPI ( P = 0·045 and P = 0·0016 respectively). Multivariate analysis identified CD21S expression as an independent factor for survival when compared with the five IPI factors. These findings indicate that CD21S expression of DLBCL tumour cells is a useful prognostic factor for survival. [ABSTRACT FROM AUTHOR]

Disease progression in B-cell chronic lymphocytic leukaemia (B-CLL) is determined by the interplay between proliferation kinetics in the proliferating compartment and cell death in the accumulating compartment. Improving our knowledge of cell cycle regulation in B-CLL cells might therefore be important for identifying therapeutic targets. Cyclin E was detected by Western blotting in purified B-CLL cells from peripheral blood samples of all 12 patient tested but not in normal peripheral blood B cells. While cyclin-dependent kinase 2 (cdk2) expression was similar in different samples, p27 and cyclin E expression was highly variable. We further investigated the regulation of p27, cyclin E and cdk2 in an in vitro model of cycling B-CLL cells. Cyclin E and cdk2 expression was increased in B-CLL cells stimulated with a CpG-oligodeoxynucleotide and interleukin-2, while p27 expression rapidly declined. This was accompanied by the increased formation of cyclin E–cdk2 complexes, which were able to phosphorylate Histone H1 in vitro. Pharmacological inhibition of cdk2 activity with Roscovitine-inhibited thymidine incorporation and Histone H1 phosphorylation. We conclude that further evaluation of cyclin E and p27 in peripheral blood cells might help to identify prognostic subgroups. In addition, inhibition of Cyclin E–cdk2 activity by Roscovitine might be a new therapeutic strategy in B-CLL. [ABSTRACT FROM AUTHOR]

The Ikaros transcription factor has been shown to play an important role in the differentiation of both myeloid and lymphoid lineages. Mice heterozygous for a dominant negative (DN) ikaros isoform develop T-cell leukaemia and lymphoma with 100% penetrance. Overexpression of DN Ikaros isoforms has been reported in some forms of leukaemia, such as childhood acute myelomonocytic and monocytic leukaemias, adult B-cell acute lymphoblastic leukaemias (B ALL) and in childhood and adult pre-B ALL. In this study, the expression of Ikaros isoforms in 49 infant and childhood leukaemia patients was analysed by reverse transcription polymerase chain reaction and Western blot analysis. We found overexpression of the DN Ikaros  6 (Ik6) isoform in a subset of leukaemia patients harbouring t(4;11) translocations. To further study the consequences of Ik6 overexpression in B ALL, we inducibly expressed Ik6 in BaF3 cells and found that Ik6 overexpression delayed cell death after interleukin-3 withdrawal, suggesting that overexpression of Ik6 found in t(4;11) B cells could contribute to leukaemogenesis by preventing the apoptosis of cells in an environment with reduced survival factors. [ABSTRACT FROM AUTHOR]

Single nucleotide polymorphisms (SNPs) of inflammatory cytokine genes were examined in 84 adult Japanese patients with chronic immune thrombocytopenic purpura (ITP) and 56 race-matched healthy controls. The SNPs examined were within the genes encoding tumour necrosis factor (TNF)- α (−238 G/A and −308 G/A), TNF- β (+252 G/A), and interleukin (IL)-1 β (−511 C/T and +3953 T/C). Of these SNPs, the frequency of the TNF- β (+252) G/G phenotype was significantly higher in ITP patients than in healthy controls (21% vs. 7%, P = 0·04, odds ratio = 3·6, 95% confidence interval 1·1–11·1), while no significant association was detected for the other SNPs. The distribution of the TNF- β (+252) phenotype was not associated with human leucocyte antigen class II alleles or the therapeutic response in ITP patients. The frequency of circulating anti-glycoprotein IIb/IIIa antibody-producing B cells was significantly higher in ITP patients with the TNF- β (+252) G/G phenotype than in those with the G/A or A/A phenotype (11·9 ± 4·9 vs. 6·8 ± 4·9 and 3·7 ± 2·8 per 105 peripheral blood mononuclear cells; P = 0·02 and P < 0·001, respectively). These findings suggest that the SNP located at TNF- β (+252) contributes to susceptibility to chronic ITP by controlling the autoreactive B-cell responses to platelet membrane glycoproteins. [ABSTRACT FROM AUTHOR]

The treatment results of indolent lymphoid malignancies in Chinese are poorly reported. The efficacy of FND (fludarabine 25 mg/m2/d, ×3; mitoxantrone 10 mg/m2/d, ×1; dexamethasone 20 mg/d, ×5; monthly cycles, ×6) in 95 Chinese patients with indolent B-cell malignancies (at diagnosis: 55, relapse/refractory disease: 40) and nine Chinese patients with T-cell large granular lymphocyte leukaemia (T-LGL leukaemia) (at diagnosis: two, refractory disease: seven) was evaluated. For B-cell malignancies, the complete response (CR), partial response (PR) and overall response (OR) rates were 50·5%, 18% and 68·5% respectively. Better results were obtained for primary versus relapse/refractory disease (CR: 60% vs. 37·5%, P = 0·03; OR: 84% vs. 47·5%, P < 0·001; median progression-free survival (PFS): 44 months vs. 22 months; 2-year PFS: 66% vs. 47%, P = 0·039; overall survival (OS): not reached vs. 32%; 2-year OS: 92% vs. 58%, P < 0·001). Responsive patients (CR/PR) had a better median PFS (44 months vs. 5 months, P < 0·001) and OS (67 months vs. 13 months, P < 0·001) than unresponsive patients. For T-LGL leukaemia, the CR and molecular-remission rates were 56% and 67% (median follow-up: 23 months). FND is an active regimen for the treatment of indolent B- and T-cell malignancies in Chinese patients, with results comparable with Western patients with similar indolent lymphomas. [ABSTRACT FROM AUTHOR]

Multiple mechanisms exist by which tumour cells can escape CD95-mediated apoptosis. Previous studies by our laboratory have shown that primary B cells from non-Hodgkin's Lymphoma (B-NHL) were resistant to CD95-induced cell death. In the current study, we have analysed the mechanisms underlying CD95 resistance in primary human lymphoma B cells. We report that FADD (FAS-associated death domain protein) and caspase-8 were constitutively expressed in lymphoma B cells and that the CD95 pathway was blocked upstream to caspase-8 activation. However, caspase-8 was processed and functional after treatment with staurosporine (STS). We found that the expression levels of FLICE (FADD-like interleukin-1 beta-converting enzyme)-Inhibitory Protein (c-FLIP) and Bcl-2-related proteins were heterogeneous in B-NHL cells and were not related to CD95 resistance. Finally, we report the absence of a CD95-induced signalling complex [death-inducing signalling complex (DISC)] in lymphoma B cells, with no FADD and caspase-8 recruitment to CD95 receptor. In contrast, DISC formation was observed in CD95-resistant non-tumoural (NT) B cells. Therefore, we propose that the absence of DISC formation in primary lymphoma B cells may contribute to protect these cells from CD95-induced apoptosis. [ABSTRACT FROM AUTHOR]

In patients with neoplastic meningitis (NM), the rapid institution of intrathecal therapy may ameliorate the course of disease, indicating that a timely diagnosis is clinically relevant. As immunocytology (IC) of cerebrospinal fluid and magnetic resonance imaging (MRI), as diagnostic methods, have potential pitfalls, the present study assessed the results of both methods, to determine the predictive capability of the initial evaluations with respect to the risk that the patient would develop NM during the course of their disease. A total of 166 individuals with B-cell non-Hodgkin's lymphoma (B-NHL; n = 95), B-acute lymphocytic leukaemia (ALL; n = 18), acute myeloid leukaemia ( n = 27) or solid tumours ( n = 26), with at least one definitive IC and MRI result within 3 weeks, were evaluated at a median follow-up of 29·5 months (range 6–53 months). IC and MRI results reached the highest concordance (98%) in B-NHL patients and were most discordant in ALL patients (43%). In haematological malignancies, IC displayed considerable sensitivity, ranging from 89% to 95%, while MRI had very low sensitivity. Conversely, MRI showed high sensitivity (100%) and specificity (92%) in solid tumours. We conclude that IC is of particular value in the diagnosis of NM due to haematological malignancies while MRI is superior to IC in the diagnosis of NM due to solid tumours. [ABSTRACT FROM AUTHOR]

Novel N-glycosylation sites are introduced by somatic mutation into the V genes of the majority of follicular lymphomas. Sites are positively selected and rare in normal memory B cells, indicating a potential role in tumour survival in the germinal centre (GC). The incidence of c. 40% in diffuse large B-cell lymphomas (DLBCL) parallels the known heterogenity of the disease. Immunodeficiency-related non-Hodgkin's lymphomas (NHL) include post-transplant lymphoproliferative disorders (PTLD) and acquired immunodeficiency syndrome-related NHL (AIDS-NHL). Most PTLD derive from B cells that carry mutated VH genes and that have completed the GC reaction. All AIDS-NHL carry mutated VH genes and variable features of GC or post-GC cells. To determine if N-glycosylation is a feature of immunodeficiency-related lymphomas, we analysed the VH genes of 19 PTLD and 36 AIDS-NHL. Novel sites were rare in PTLD (4/19), similar to memory B cells ( P = 0·15). AIDS-NHL, including DLBCL and Burkitt's lymphomas (BL), showed heterogeneity with 16 of 36 (44%) having novel sites. The findings indicate no selection of N-glycosylation sites in PTLD, consistent with post-GC features. The variable incidence of N-glycosylation sites in AIDS-NHL mirrors that in DLBCL and sporadic BL of immunocompetent hosts, supporting the known heterogeneity of these disorders, and possibly pointing to distinct routes of tumour development. [ABSTRACT FROM AUTHOR]

Dysregulation of fibroblast growth factor receptor 3 ( FGFR3) by the translocation t(4;14)(p16;q32) occurs in 15% of multiple myeloma (MM) patients and confers a growth and survival advantage to malignant plasma cells. As FGFR3 is a molecular target, we assessed the therapeutic potential of the FGFR-specific tyrosine kinase inhibitors SU5402 and SU10991 in MM. SU5402 inhibited FGFR3 phosphorylation in vitro and in murine MM tumour models. B cells dependent on FGFR3 for survival were specifically sensitive to SU5402. A panel of 11 human myeloma cell lines was studied, five bearing the t(4;14) translocation. The KMS11 human myeloma cell line, which expresses constitutively active mutant FGFR3, displayed an 85% decrease in S-phase cells, a 95% increase in G0/G1 cells, and 4·5-fold increase in apoptotic cells after 72 h treatment with 10 μmol/l SU5402. Activated extracellular signal-regulated kinases  1 and 2 and signal transducer and activator of transcription 3 were rapidly down-regulated after SU5402 treatment. In human myeloma cell lines expressing wild-type FGFR3 the stimulating effect of aFGF ligand was abrogated by SU5402 treatment. Myeloma cells lacking the t(4;14) or with the t(4;14) and a secondary RAS mutation did not respond to therapy. These findings support the development of clinical trials of early intervention with FGFR3 inhibitors in t(4;14) myeloma. [ABSTRACT FROM AUTHOR]

We have investigated whether intracellular signal transduction molecules can be used as immunohistological markers of normal and neoplastic human leucocytes in routine tissue sections. We obtained selective labelling of white cells for eight such molecules (the ‘linker’ molecules SLP-76 and BLNK, the Src family kinases Lyn, Fyn, Syk and Hck, and the phospholipases PLC- γ1 and PLC- γ2). Antibodies to SLP-76 and PLC- γ1 selectively labelled T cells, and antibodies to BLNK, Lyn, Fyn, Syk and PLC- γ2 labelled B cells (although Fyn immunostaining was restricted to mantle zone B cells). Antibodies to the Syk and Hck kinases labelled probable thymocyte precursors at the periphery of the thymic cortex. In addition to lymphoid cells, several other leucocyte types were immunostained (e.g. SLP-76, Lyn, Syk and Hck were found in megakaryocytes, myeloid cells and/or macrophages, and PLC- γ2 was detected in arterial endothelium). SLP-76 and PLC- γ1 were found in most T-cell lymphomas studied, and some B-cell lymphomas were also positive for PLC- γ1 (e.g. diffuse large cell and Burkitt's lymphoma). The five B cell-associated markers were found in most B-cell non-Hodgkin's lymphomas, although some diffuse large B-cell lymphomas were negative (e.g. for Lyn) and anti-Fyn tended not to stain small B-cell neoplasms. The observation that a range of leucocyte signalling molecules can be detected in routine biopsies offers new possibilities for studying normal and neoplastic human white cells in diagnostic tissue samples. [ABSTRACT FROM AUTHOR]

Primary intraocular lymphoma (PIOL) is a rare presentation of lymphoma that is particularly difficult to recognize. In our institution, 36 cases of PIOL were diagnosed between March 1997 and July 2002. The recognition of lymphoma cells by cytology with or without immunophenotyping on slides generated a strong suspicion of the diagnosis in 34 of 36 cases. The diagnosis was confirmed by measurement of interleukin-10 (IL-10) in the vitreous humour or aqueous humour; high levels were observed in 35 of 36 cases, all were of B-cell origin. As expected, the only case with T-cell lymphoma had a very low level of IL-10. Furthermore, IL-10 levels excluded this diagnosis in two cases that were incorrectly suspected of PIOL after cytological examination. Finally, detection of clonality by polymerase chain reaction techniques, performed in 29 cases, represented a helpful tool in diagnosing PIOL as this approach definitively confirmed the diagnosis of B- or T-cell lymphoma in 17 cases. [ABSTRACT FROM AUTHOR]

B-cell chronic lymphocytic leukaemia (B-CLL) is a neoplastic disorder characterized by defective apoptosis, cell accumulation in G0/G1, and high expression of BCL2 oncogene. Intracellular cyclic adenosine monophosphate (cAMP) accumulation increases the chemosensitivity of B-CLL cells in vitro and in vivo. In the present study, we investigated the effects of β2-adrenergic compounds, well known cAMP-inducing drugs, on the in vitro survival of leukaemia cells. In contrast to the short-acting β2-mimetic (β2Mim) salbutamol, a consistent pro-apoptotic effect was observed with the long-acting β2Mim salmeterol and formoterol. Normal B cells isolated from control donors were totally resistant to the above molecules. These compounds also increased chlorambucil- and fludarabine-induced death of B-CLL cells. Blockade of β-adrenergic receptor signalling or cAMP did not alter B-CLL apoptosis with β2 Mimagents. Leukaemia cell apoptosis by β2Mim correlated with an increase in calcium influx, decreased bcl-2 protein and mRNA levels, increase in BAX gene expression and a marked rise in BCL2/BAX mRNA ratios. Interleukin-4, a cytokine that increases bcl-2 expression in B-CLL cells, rescued leukaemia cell from apoptosis with β2Mim. These data show that long-acting β2-adrenergic agents promote apoptotic leukaemia cell death through an adrenoreceptor- and cAMP-independent, Ca2+-dependent mechanism. [ABSTRACT FROM AUTHOR]

Despite a successful outcome of the anti-D prophylaxis programme, alloimmunization still occurs. The aim of this study was to estimate the frequency of Rh-specific B lymphocytes in the peripheral blood of nine Rh-alloimmunized individuals at different time intervals after parturition. The donors’ B lymphocytes were transformed with Epstein–Barr virus (EBV) and cultured at different cell densities over a feeder of human fetal fibroblasts. Culture supernatants were screened for human immunoglobulin by enzyme-linked immunosorbent assay (ELISA) and for anti-Rh antibody by using a direct haemagglutination technique. The percentage of CD19+ B lymphocytes in peripheral blood was determined by flow cytometry, and the frequency of Rh-specific B lymphocytes was estimated by limiting-dilution assay (LDA). The frequency of Rh-specific B lymphocytes varied from 1 : 150 to 1 : 27 850 in different donors. There was a decrease in this frequency and level of anti-Rh antibody with increase in time interval between bleeding and last exposure to the antigen. Furthermore, a positive correlation was observed between the titre of Rh-specific antibody and frequency of Rh-specific B cells in each of three subjects bled at multiple time-points postdelivery. The magnitude of the specific antibody response to Rh antigens varies greatly in Rh-alloimmunized women, which partly reflects the difference in frequency of specific B cells in these individuals. [ABSTRACT FROM AUTHOR]

Summary. The available data on rituximab in combination with chemotherapy confirm that the addition of an independently active biological agent to full-dose standard chemotherapy results in higher rates of complete response, lower rates of relapse, prolonged survival, little additional toxicity and no compromise of the dose intensity of standard chemotherapy regardless of age and risk group. Given the strength of these data, the British Committee for Standards in Haematology believes that rituximab should be available for prescription by UK haematologists and oncologists according to its licensed indication in patients with diffuse large B-cell lymphoma until further data are available to confirm or refute these results. We consider that the use of rituximab with chemotherapy in aggressive lymphoma is cost-effective and that failure to support its introduction will be strongly in conflict with professional and patient opinion. [ABSTRACT FROM AUTHOR]

Over the past century, the field of antibody discovery has undergone significant evolution, excluding the current exploration stage of artificial intelligence‐based antibody generation and the often overlooked non‐animal sourced antibody discovery, which typically requires mature in vitro affinity and the selection of high‐quality antigen formulations. This journey has traversed various stages, from methods involving serum‐based antibody acquisition, the isolation of B cells capable of perpetual antibody production through hybridoma technology, to the in‐depth exploration of genetic material using the phage display system, and the current stage involving diverse single B cell screening techniques. Additionally, the emergence of machine learning has brought impressive scientific and technological breakthroughs across research domains, proving to be a powerful application in the field of antibody discovery. However, each technique comes with its limitations, such as variability and control challenges in serum‐based acquisition, lengthy and difficult hybridoma‐derived antibody development, potential limitations in sequence and epitope diversity due to immunization biases in phage display techniques, and costly single B cell screening. Protein mass spectrometry sequencing, with shorter acquisition time and lower costs, is seen as a shortcut by diagnostic companies, impacting traditional antibody development. In diagnostic antibody development, methodological differences in downstream assays and the impact of constant regions outside the Fv core are often neglected. This paper deeply analyzes challenges, proposing innovative strategies for the next generation of diagnostic antibody development. Aimed at moving closer to the gold standard of antibody discovery, these strategies enhance the competitiveness of diagnostic reagent products. [ABSTRACT FROM AUTHOR]

The article offers update on bone fracture prevention and treatments for conditions such as osteoporosis. It discusses findings of several research including fracture repair via bone remodeling using osteoclasts, potential of high frequency sound waves to convert bone marrow derived mesenchymal stem cells into bone cells, and a demineralised bone paper biomaterial used to advanced the understanding of bone biology, model disease progression and screen drug responses.

This work investigates the existence and asymptotic behavior of solutions to a nonlocal dispersal in‐host viral model with humoral immunity. The model features both spatial movement of virus and humoral immunity response to the virus. This paper gives the principal eigenvalue (H0$\mathcal {H}_0$) of the nonlocal dispersal problem, and it is verified to be a critical value that determines the infection dynamics. The uninfected equilibrium is unique and stable for H0≤0$\mathcal {H}_0\le 0$. For H0>0$\mathcal {H}_0>0$, the equilibrium is not stable, and infected with/without B cells response equilibrium emerges. This paper also establishes the dynamics of infected equilibria. Numerical simulations are carried out to demonstrate the analytical results of this study. [ABSTRACT FROM AUTHOR]

The clonal selection theory (CST) is the centrepiece of the current paradigm used to explain immune recognition and memory. Throughout the past decades, the original CST had been expanded and modified to explain new experimental evidences since its original publication by Burnet. This gave origin to new paradigms that govern experimental immunology nowadays, such as the associative recognition of antigen model and the stranger/danger signal model. However, these new theories also do not fully explain experimental findings such as natural autoimmune immunoglobulins, idiotypic networks, low and high dose tolerance, and dual‐receptor T and B cells. To make sense of these empirical data, some authors have been trying to change the paradigm of immune cognition using a systemic approach, analogies with brain processing and concepts from second‐order cybernetics. In the present paper, we review the CST and some of the theories/hypotheses derived from it, focusing on immune recognition. We point out their main weaknesses and highlight arguments made by their opponents and believers. We conclude that, until now, none of the proposed theories can fully explain the totality of immune phenomena and that a theory of everything is needed in immunology. [ABSTRACT FROM AUTHOR]

Epigallocatechin‐3‐gallate (EGCG) is a major bioactive compound in tea polyphenol extract. After ingestion, EGCG reaches the intestine and may commence anti‐inflammation in the intestinal organ. Thus, in this paper, the anti‐inflammatory effect of EGCG was studied using lipopolysaccharide (LPS)‐induced inflammation in RAW 264.7 cells. LPS induction instigated morphological deformation extensively which was normalized by EGCG. In LPS‐induced macrophage cells, EGCG was found to lower cellular nitric oxide (32% of LPS group) and intercellular ROS level (45.4% of LPS group). It also suppressed the expression of IL‐1β (LPS 132.6 ± 14.6, EGCG 10.67 ± 3.65), IL‐6 (LPS 2994.44 ± 178.5, EGCG 408.33 ± 52.34), TNF‐α (LPS 27.11 ± 2.84, EGCG 1.22 ± 0.03), and iNOS (LPS 40.45 ± 11.17, EGCG 10.24 ± 0.89). The GO function analysis identified that these differential genes involved 24 biological processes, 18 molecular functions, and 19 cellular component‐related processes. KEGG pathway enrichment analysis revealed that LPS significantly affects NF‐κB, TNF, and TLR signaling pathways. Western blotting revealed that EGCG diminished P‐IκB/IκB ratio by 75% and p‐p65/p65 by 50% compared to the LPS group. Finally, Arg‐1 and CD‐206 mRNA expression were determined by RT‐PCR, which was consistent with the RNA‐Seq result. These findings indicate that EGCG exerts an anti‐inflammatory effect by reducing NO and ROS production, suppressing TLR4 protein expression, and inhibiting IκB and p65 phosphorylation. [ABSTRACT FROM AUTHOR]

Allergic rhinitis (AR) is a global health problem with increasing prevalence and association with an enormous medical and socioeconomic burden. New recognition of immune cells such as type 2 innate lymphocytes (ILC2s), T helper (Th2) 2 cells, follicular helper T cells, follicular regulatory T cells, regulatory T cells, B cells, dendritic cells, and epithelial cells in AR pathogenesis has been updated in this review paper. An in‐depth understanding of the mechanisms underlying AR will aid the identification of biomarkers associated with disease and ultimately provide valuable parameters critical to guide personalized targeted therapy. As the only etiological treatment option for AR, allergen‐specific immunotherapy (AIT) has attracted increasing attention, with evidence for effectiveness of AIT recently demonstrated in several randomized controlled trials and long‐term real‐life studies. The exploration of biologics as therapeutic options has only involved anti‐IgE and anti‐type 2 inflammatory agents; however, the cost‐effectiveness of these agents remains to be elucidated precisely. In the midst of the currently on‐going COVID‐19 pandemic, a global life‐threatening disease, although some studies have indicated that AR is not a risk factor for severity and mortality of COVID‐19, this needs to be confirmed in multi‐centre, real‐life studies of AR patients from different parts of the world. [ABSTRACT FROM AUTHOR]

CD38 is a multifunctional receptor and enzyme present on the surface of B lymphocytes, which can induce B lymphocytes proliferation and apoptosis by crosslinking related cytokines to affect the function of B cells, thus affecting immune regulation in humans and promoting tumorigenesis. The level of CD38 expression in B cells has become an important factor in the clinical diagnosis, treatment, and prognosis of malignant tumors and other related diseases. Therefore, studying the relationship between CD38 expression on the surface of B cells and the occurrence of the disease is of great significance for elucidating its association with disease pathogenesis and the clinical targeted therapy. In this paper, we review the effects of CD38 on B‐cell activation, proliferation, and differentiation, and elaborate the functional role and mechanism of CD38 expression on B cells. We also summarize the relationship between the level of CD38 expression on the surface of B cells and the diagnosis, treatment, and prognosis of various diseases, as well as the potential use of targeted CD38 treatment for related diseases. This will provide an important theoretical basis for the scientific research and clinical diagnosis and treatment of B‐cell‐related diseases. [ABSTRACT FROM AUTHOR]

Lists research papers related to immunology to be published in the journal. "T Cells Homeostasis in Mice Exposed to Airborne Xenobiotics," by Nadzieja Drela, Justyna Bien, and Ewa Kozlowska; "B Cell Reconstruction by Transplantation of B220+ CD117+ B-lymphoid Progenitors Into Irradiated Mice," by Susumu Kawaguchi; "TGF-β1 Increases CXCR4 Expression, SDF-1alpha-stimulated Signaling and HIV-1 Entry in Human Monocyte-derived Macrophages," by Jeffrey Harrison.

Summary: A subset of individuals with 'primary' or 'idiopathic' immune thrombocytopenia (ITP) who fail to respond to conventional first‐ and second‐line agents or who lose responsiveness are considered to have 'refractory' disease (rITP), placing them at increased risk of bleeding and complications of intensive treatment. However, the criteria used to define the refractory state vary among studies, which complicates research and clinical investigation. Moreover, it is unclear whether rITP is simply 'more severe' ITP, or if there are specific pathogenic pathways that are more likely to result in refractory disease, and whether the presence or development of rITP can be established or anticipated based on these differences. This paper reviews potential biological features that may be associated with rITP, including genetic and epigenetic risk factors, dysregulation of T cells and cytokine networks, antibody affinity and specificity, activation of complement, impaired platelet production and alterations in platelet viability and clearance. These findings indicate the need for longitudinal studies using novel clinically available methodologies to identify and monitor pathogenic T cells, platelet antibodies and other clues to the development of refractory disease. [ABSTRACT FROM AUTHOR]

Summary: Since its first description by Evans in 1951, this syndrome has been linked to chronic immune thrombocytopenia with the concurrent or delayed onset of autoimmune haemolytic anaemia or neutropenia. For decades, the evolution of Evans syndrome (ES) has carried a poor prognosis and often resulted in chronic steroid exposure, multiple immune suppressing medications directed against T or B lymphocytes, and splenectomy. This paper presents a new view of ES based on recent advances in genomics which begin to classify patients based on their underlying molecular variants in previously described primary immune disorders. This has opened up new avenues of targeted therapy or bone marrow transplant at rather than broad long‐term immune suppression or splenectomy. Importantly, recent studies of the full lifespan of ES suggest that at least 80% of those paediatric patients will progress to various clinical or biological immunopathological manifestations with age despite the resolution of their cytopenias. Those patients merit long‐term follow‐up and monitoring in dedicated transition programs to improve outcome at the adult age. [ABSTRACT FROM AUTHOR]

The article presents a list of forthcoming books about immunology. These include "IL-5 Target Genes Involved in B Cell Terminal Maturation," by Keisuke Horikawa and K. Takatsu, "The Riddle of the Dual Expression of IgM and IgD," by Roland Geisberger, Marinus Lamers and Gernot Achatz, and "Anti-Idiotype Antibody Induced Cellular Immunity in Mice Transgenic for Human Carcinoembryonic Antigen," by Asim Saha, Sunil Chaterjee, Kenneth Foon and Malaya Chatterjee.

The article focuses on the detection of circulating tumour deoxyribonucleic acid (DNA) in patients with aggressive B-cell non-Hodgkin lymphoma. It states that methods to detect any disease in patients with diffuse large B cell lymphoma (DLBCL) or mediastinal large B-cell lymphoma (MLBCL) rely primarily on imaging methods. It further mentions that these methods are associated with significant cost and radiation exposure.

NF‐κB (nuclear factor kappa light chain enhancer of activated B cells) signaling pathway is involved in the occurrence and development of various kinds of inflammation, including rheumatoid arthritis (RA). In this paper, the relationship between the activation or inhibition of NF‐κB and the pathogenesis of RA is discussed. It is found that activated NF‐κB operates a dual‐aspect effect which can either promote or suppress inflammation. When NF‐κB is inhibited, the symptoms of RA are significantly improved. The specific role of NF‐κB is closely related to its upstream stimulator and downstream activator. Therefore, we review the research on NF‐κB in RA over the past 20 years in order to have a clearer understanding of its mechanism. [ABSTRACT FROM AUTHOR]

The maintenance of inner integrity of an organism is founded on the proper performance of two immunity branches, innate and adaptive immune responses. Recently, it became apparent that subset of splenic B cells named marginal zone B cells (MZB cells) exhibits unique developmental and functional features that bridge these two immunity branches. Strategically positioned at the site where blood and lymph are filtered, MZB cells represent a population of sentinels that rapidly proliferate and differentiate into IgM plasmablast cells when encountered with blood‐borne, thymus‐independent (TI) Ags. Moreover, MZB cells have intrinsic capability to induce potent CD4+ helper T cell response and cytokine production upon stimulation with soluble antigens. Due to their ability to overcome a time gap prior the establishment of the full adaptive response towards pathogens, MZB cells connect and direct innate and adaptive immunity. An additional interesting characteristic of MZB cells is capacity to function as regulatory cells in autoimmune processes. MZB cells may also contribute to the control of autoimmunity via the induction of tolerance by apoptotic cells. Importantly, in the clear association with inflammation and autoimmunity, MZB cells may transform into MALT lymphoma, representing a concurrence point for the infection, immunity and malignancy. This paper presents an insight into the complex biology of marginal zone B cells and their role in intertwining and directing innate and adaptive immune processes at the physiological and pathological level. [ABSTRACT FROM AUTHOR]

As the amount of biomedical information available in the literature continues to increase, databases that aggregate this information continue to grow in importance and scope. The population of databases can occur either through fully automated text mining approaches or through manual curation by human subject experts. We here report our experiences in populating the National Institute of Allergy and Infectious Diseases sponsored Immune Epitope Database and Analysis Resource ( IEDB, http://iedb.org), which was created in 2003, and as of 2012 captures the epitope information from approximately 99% of all papers published to date that describe immune epitopes (with the exception of cancer and HIV data). This was achieved using a hybrid model based on automated document categorization and extensive human expert involvement. This task required automated scanning of over 22 million PubMed abstracts followed by classification and curation of over 13 000 references, including over 7000 infectious disease-related manuscripts, over 1000 allergy-related manuscripts, roughly 4000 related to autoimmunity, and 1000 transplant/alloantigen-related manuscripts. The IEDB curation involves an unprecedented level of detail, capturing for each paper the actual experiments performed for each different epitope structure. Key to enabling this process was the extensive use of ontologies to ensure rigorous and consistent data representation as well as interoperability with other bioinformatics resources, including the Protein Data Bank, Chemical Entities of Biological Interest, and the NIAID Bioinformatics Resource Centers. A growing fraction of the IEDB data derives from direct submissions by research groups engaged in epitope discovery, and is being facilitated by the implementation of novel data submission tools. The present explosion of information contained in biological databases demands effective query and display capabilities to optimize the user experience. Accordingly, the development of original ways to query the database, on the basis of ontologically driven hierarchical trees, and display of epitope data in aggregate in a biologically intuitive yet rigorous fashion is now at the forefront of the IEDB efforts. We also highlight advances made in the realm of epitope analysis and predictive tools available in the IEDB. [ABSTRACT FROM AUTHOR]

This paper formulates a virus dynamics model with impairment of B‐cell functions. The model incorporates two modes of viral transmission: cell‐free and cell‐to‐cell. The cell‐free and cell‐cell incidence rates are modeled by general functions. The model incorporates both, latently and actively, infected cells as well as three distributed time delays. Nonnegativity and boundedness properties of the solutions are proven to show the well‐posedness of the model. The model admits two equilibria that are determined by the basic reproduction number R0. The global stability of each equilibrium is proven by utilizing Lyapunov function and LaSalle's invariance principle. The theoretical results are illustrated by numerical simulations. The effect of impairment of B‐cell functions and time delays on the virus dynamics are studied. We have shown that if the functions of B‐cell is impaired, then the concentration of viruses is increased in the plasma. Moreover, we have observed that increasing the time delay will suppress the viral replication. [ABSTRACT FROM AUTHOR]

This paper studies an (n+4)‐dimensional nonlinear virus dynamics model that characterizes the interactions of the viruses, susceptible host cells, n‐stages of infected cells, B cells and cytotoxic T lymphocyte (CTL) cells. Both viral and cellular infections have been incorporated into the model. The infected‐susceptible and virus‐susceptible infection rates as well as the generation and removal rates of all compartments are described by general nonlinear functions. Five threshold parameters are computed, which insure the existence of the equilibria of the model under consideration. A set of conditions on the general functions has been established, which is sufficient to investigate the global dynamics of the model. The global asymptotic stability of all equilibria is proven by utilizing Lyapunov function and LaSalle's invariance principle. The theoretical results are illustrated by numerical simulations of the model with specific forms of the general functions. [ABSTRACT FROM AUTHOR]

Lymphomatoid granulomatosis (LYG) is an angiocentric and angiodestructive lymphoproliferative disease which can involve multiple organs of the body and is most common in the lungs. Its pathological features are proliferation of large atypical B‐cells related to Epstein–Barr virus, T‐cell infiltration and tissue necrosis. This disease is rare, and LYG which uniquely involves the central nervous system (CNS) is extremely rare. In this paper, we report a case of isolated lymphomatoid granulomatosis of the CNS (iCNS‐LYG) diagnosed by histological biopsy and we review the clinical features of all similar cases reported in the past 46 years. A total of 49 cases of iCNS‐LYG have been reported to date. The clinical, imaging and pathological features of iCNS‐LYG are discussed in combination with a literature review. [ABSTRACT FROM AUTHOR]

Allergic rhinitis (AR) is a disease with high prevalence all over the world and therefore needs to be thoroughly investigated and treated accordingly. The mechanisms underlying the pathology and treatment of AR have been widely studied, but many aspects remain unclear and warrant further investigations. This review presents an overview of recently published papers highlighting the risk factors, mechanisms, and treatment of AR. Additionally, recent studies discussing the role of single nucleotide polymorphism, DNA methylation, regulatory B cells, group 2 innate lymphoid cells, immunotherapy, and biologics in AR are also covered. [ABSTRACT FROM AUTHOR]

Aim: A significant proportion of patients with minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS) are either steroid dependent or steroid resistant, requiring long‐term calcineurin inhibitors (CNI) use. Rituximab has more favourable safety profile. The present study was undertaken to evaluate the efficacy and safety of rituximab in CNI‐dependent patients. Methods: This was a prospective observational study conducted from July 2014 to February 2018. Steroid‐dependent nephrotic syndrome or steroid‐resistant nephrotic syndrome (biopsy proven MCD/FSGS), who were CNI dependent were enrolled. Mean age at enrolment was 22.77 ± 7.45 years. All patients received rituximab at a dose of 375 mg/m2 at entry in the study. CD‐19 levels were monitored monthly and patients having CD‐19 levels >5/μL and/or > 1% received additional low‐dose (100 mg) of rituximab. Results: A total of 24 patients were followed up for 12 months. At the end of 6 and 12 months, 87.5% and 79.16% of the patients achieved remission, respectively. Eight (33.33%) patients developed relapse. The mean dose of rituximab in the first year was 791 mg. The average cost of rituximab in the first year was 487.17$. Rituximab was well‐tolerated, with mild infusion reactions, respiratory tract infection and oral candidiasis in 5 (20.83%), 5 (20.83%) and 1 (4.17%) patient, respectively. Conclusions: CD‐19 targeted rituximab is a safe and cost‐effective agent in remission maintenance in adults with CNI dependent. Over three‐fourths of the patients with CNI‐dependent podocytopathy maintain clinical remission with CD‐19 targeted rituximab therapy. SUMMARY AT A GLANCE: This paper shows that rituximab, a monoclonal antibody‐based therapy that depletes CD‐19 and CD‐20‐positive B cells, may be an alternative approach to maintain remission in calcineurin‐inhibitor dependent podocytopathies. [ABSTRACT FROM AUTHOR]

The naked mole rat (Heterocephalus glaber, NMR) is a rodent with exceptional longevity, low rates of age‐related diseases and spontaneous carcinogenesis. The NMR represents an attractive animal model in longevity and cancer research, but there are no NMR‐specific antibodies available to study its immune system with respect to age‐ and cancer‐related questions. Substantial homology of major NMR immune cell markers with those of Guinea pig, human and, to a lesser extent, mouse and rat origin are implicated for the existence of immunological cross‐reactivity. We identified 10 antibodies recognising eight immunophenotypic markers expressed on the NMR's T and B lymphocytes, macrophages/monocytes and putative haematopoietic precursors and used them for an immunophenotyping of leukocyte subsets of peripheral blood, spleen and bone marrow samples. Overall, we found that the leukocyte composition of NMR peripheral blood is comparable to that of mice. Notably, the frequency of cytotoxic T cells was found to be lower in the NMR compared to corresponding mouse tissues and human blood. Antibodies used in the present paper are available either commercially or from the scientific community and will provide new opportunities for the NMR as a model system in ageing‐ and cancer‐related research areas. [ABSTRACT FROM AUTHOR]

Transgenic mice expressing human major histocompatibility complex class II (MHCII) risk alleles are widely used in autoimmune disease research, but limitations arise due to non‐physiologic expression. To address this, physiologically relevant mouse models are established via knock‐in technology to explore the role of MHCII in diseases like rheumatoid arthritis. The gene sequences encoding the ectodomains are replaced with the human DRB1*04:01 and 04:02 alleles, DRA, and CD74 (invariant chain) in C57BL/6N mice. The collagen type II (Col2a1) gene is modified to mimic human COL2. Importantly, DRB1*04:01 knock‐in mice display physiologic expression of human MHCII also on thymic epithelial cells, in contrast to DRB1*04:01 transgenic mice. Humanization of the invariant chain enhances MHCII expression on thymic epithelial cells, increases mature B cell numbers in spleen, and improves antigen presentation. To validate its functionality, the collagen‐induced arthritis (CIA) model is used, where DRB1*04:01 expression led to a higher susceptibility to arthritis, as compared with mice expressing DRB1*04:02. In addition, the humanized T cell epitope on COL2 allows autoreactive T cell‐mediated arthritis development. In conclusion, the humanized knock‐in mouse faithfully expresses MHCII, confirming the DRB1*04:01 alleles role in rheumatoid arthritis and being also useful for studying MHCII‐associated diseases. [ABSTRACT FROM AUTHOR]

Key clinical message: Ayurveda Rasayana Therapy (ART) may serve as a safe and effective alternative treatment option for chemo‐intolerance high‐grade stage IV follicular lymphoma patients for increasing survival and tumor regression. Follicular lymphoma (FL), also called follicle center lymphoma/nodular lymphoma, observed in the B lymphocytes (B‐cells). Available therapeutic options for follicular lymphoma are associated with various side effects and, patients with co‐morbidities can seldom tolerate the chemotherapy regimens. Rasayana therapy not only resulted in tumor regression and improved survival but also dealt with the adverse effects of previous chemotherapy drugs. Herein, we present a case of a 74‐year‐old female diagnosed with Follicular lymphoma who had undergone three cycles of chemotherapy with unresolved disease outcome and serious adverse events. The patient refused to undergo further cycles of chemotherapy. Her family decided to start Ayurveda treatment for her as an alternative therapy for cancer care. On thorough case taking considering the Ayurveda parameters personalized Rasayana therapy as planned for the patient with an aim for improvement in Quality of Life (QoL), increasing survival, and optimizing body's immune response to fight the tumor. After treatment of 8 months, this case demonstrated partial tumor response as evidenced by PET‐CT‐scan. Quality of Life as evaluated using FACT‐G was also seen improved besides significant improvement in physical performance status evaluated using ECOG. The patient showed a survival of 3.5 years after starting Ayurveda Rasayana Therapy (ART). Rasayana therapy was well tolerated by the patient. This case report indicates the potential role of ART as a therapeutic option in geriatric cancer patients who are not eligible for cytotoxic interventions. Case warrants further systematic investigation to evaluate the potential role of ART in the treatment of geriatric cancer patients. [ABSTRACT FROM AUTHOR]

In the preceding paper a population of lymphoid cells was identified which (1) were derived from germinal centres in the appendix, (2) were localized in follicular structures elsewhere, and (3) could perform as antibody-forming cell precursors. The present paper presents evidence (1) that germinal centres in the spleen and lymph nodes perform the same function as germinal centres in the appendix, and (2) that germinal centres are dependent upon a stream of cells derived from the bone marrow. A new hypothesis is put forward regarding the origin and cellular kinetics of the B-cell system in mammals. It is proposed that germinal centres throughout the body function as an essentially antigen-dependent amplification system for the B-cell population of lymphocytes. Implications of this hypothesis are discussed. [ABSTRACT FROM AUTHOR]

Summary: Background: Thyroid eye disease (TED) is an autoimmune inflammatory disease that can be disfiguring and potentially sight threatening. Suppression of inflammation in active disease can reduce the risk of visual loss and limit long‐term sequelae. Current management involves inflammation suppression using glucocorticoids. The aim of this study was to evaluate the efficacy of early disease intervention with targeted immunomodulatory therapy to alter disease course. This paper reports the efficacy of low‐dose rituximab in reducing clinical activity in TED in a small population. Methods: A retrospective audit of consecutive patients with active TED managed primarily with a 100 mg rituximab infusion. Further glucocorticoid or steroid‐sparing agents were prescribed if clinically indicated. Clinical activity score, VISA overall severity score and Oxford Quality of Life score were recorded at each visit as well as TSH receptor antibody levels (TRAb), B cell subsets and adverse reactions. Results: Twelve patients had mean follow‐up of 6.3 months. Clinical activity scores significantly decreased (mean score 5.08 to 1.58; P < 0.001), VISA overall severity scores reduced by 50% from 12 to 6, P < 0.001 and the mean cumulative dose of IV methylprednisolone was 2.3 g. 100 mg rituximab induced significant CD19+ B cell depletion (n = 8, P < 0.001). There was no significant reduction in serum TRAb (n = 8, P = 0.06). A transient infusion‐related rash was the only adverse effect, n = 4. QoL scores did not differ markedly before and after treatment. Conclusion: Low‐dose rituximab is an efficacious, well‐tolerated and safe treatment for active TED; reducing disease activity and allowing reduced administration of systemic steroid. [ABSTRACT FROM AUTHOR]

In this issue of I CPT: Pharmacometrics and Systems Pharmacology i , Leonov et al.[1] present a powerful tool for quantitative systems pharmacology (QSP) practitioners and immune modelers: "CYTOCON DB", a comprehensive and manually curated database of publicly available concentrations of cells, cytokines, chemokines, and other molecules in various human organs in both healthy and diseased states. Finally, CYTOCON DB could both generate new databases, and be linked with existing databases for potentially generating both broad and deep knowledge networks in immunology and MID3. [Extracted from the article]

Among the B-cell lymphoproliferative disorders, monoclonal gammopathy of undetermined significance (MGUS) is the humoral counterpart to monoclonal B-cell lymphocytosis. This review introduces the papers from the section devoted to MGUS at the International Workshop entitled ‘Monoclonal B-cell lymphocytosis and chronic lymphocytic leukaemia: environmental and genetic risk factors.’ [ABSTRACT FROM AUTHOR]

Abstract: Probabilistic modeling is fundamental to the statistical analysis of complex data. In addition to forming a coherent description of the data‐generating process, probabilistic models enable parameter inference about given datasets. This procedure is well developed in the Bayesian perspective, in which one infers probability distributions describing to what extent various possible parameters agree with the data. In this paper, we motivate and review probabilistic modeling for adaptive immune receptor repertoire data then describe progress and prospects for future work, from germline haplotyping to adaptive immune system deployment across tissues. The relevant quantities in immune sequence analysis include not only continuous parameters such as gene use frequency but also discrete objects such as B‐cell clusters and lineages. Throughout this review, we unravel the many opportunities for probabilistic modeling in adaptive immune receptor analysis, including settings for which the Bayesian approach holds substantial promise (especially if one is optimistic about new computational methods). From our perspective, the greatest prospects for progress in probabilistic modeling for repertoires concern ancestral sequence estimation for B‐cell receptor lineages, including uncertainty from germline genotype, rearrangement, and lineage development. [ABSTRACT FROM AUTHOR]

This study delves into the impact of mesenchymal stem cells derived from bone marrow (BM‐MSCs) and those sourced from dental pulp (DP‐MSCs) on the recovery of motor function and morphological aspects of the rat's sciatic nerve after crush injuries. The findings highlight that the groups treated with BM‐MSCs, DP‐MSCs or a combination of both (BM + DP‐MSCs) displayed enhanced sciatic functional index values when juxtaposed with the sham group. This points to bettered motor functionalities. A deeper morphological analysis showed that all the groups had retained perineurium structure and fascicular arrangement. Notably, the sham and BM‐MSCs groups had very few inconsistencies. All groups showed standard vascular density. Remarkably, the combined treatment group (BM + DP‐MSCs) presented diminished oedema and a lower count of inflammatory cells. Through immunohistochemical methods, the presence of S100 expression was noted in the groups that underwent treatment. In summation, the study suggests that both BM‐MSCs and DP‐MSCs, whether used singly or in combination, can significantly aid in motor function restoration and morphological enhancements. An interesting observation from our research and earlier studies is that stem cells from dental pulp, which are sourced with less discomfort from milk and wisdom teeth, show a heightened propensity to evolve into nerve cells. This is in contrast to the more uncomfortably acquired BM‐MSCs. [ABSTRACT FROM AUTHOR]

Parsaclisib, a potent and selective phosphatidylinositol 3 kinase δ inhibitor, has been investigated for the treatment of B‐cell malignancies and studied in patients with autoimmune diseases and myelofibrosis. The CITADEL‐101 study (NCT02018861) assessed safety, tolerability, and preliminary efficacy of parsaclisib in patients with relapsed or refractory non‐Hodgkin lymphoma. This study evaluated the cardiac safety of parsaclisib as monotherapy based on data from 72 patients enrolled in the CITADEL‐101 study. Time‐matched pharmacokinetic and ECG measurements were collected at specified times for 69 patients receiving monotherapy in doses of 5, 10, 15, 20, 30, and 45 mg once daily. Based on the categorical outlier analysis, no dose‐dependent effect was observed on the incidence of outliers in QT interval corrected for heart rate (HR) by Fridericia's method (QTcF), HR, or cardiac conduction. Based on central tendency analysis, the least square means (LSMs) (90% confidence interval [CI]) of ΔQTcF from the central tendency analysis ranged from −6.83 (−18.8 to 5.19) to 4.75 ms (0.410–9.09) across dose groups (below 20 ms, the threshold of large QT effects) and was not considered dose dependent. Moreover, the LSMs of ΔHR, ΔPR interval, and ΔQRS interval were minor. From the concentration‐ΔQTcF analyses, the predicted ΔQTcF (90% CI) for all dose levels was between 0.365 (−1.75 to 2.48) and 7.87 ms (0.921–14.8), with the highest upper limit of CIs well below 20 ms, and therefore, a large QT/QTc effect was ruled out up to the highest dose level (45 mg) investigated. Overall, parsaclisib at the dose ranges studied did not reveal concentration‐dependent effects on change in QTcF and did not have a significant effect on HR or cardiac conduction. [ABSTRACT FROM AUTHOR]

Background: Primary cutaneous B-cell lymphomas (PCBCL) are cutaneous non-Hodgkin lymphomas and can be classified clinically and by prognosis. The aim of this paper is to perform a review of standard and new treatments. Method: This paper provides a literature review of the different treatments of PCBCL. Results: Surgery and radiotherapy remain the standard therapies in isolated cutaneous lesions. Systemic or intralesional interferon (IFN)-α may be an alternative in PCBCL with diffuse cutaneous lesions. In aggressive forms with poor prognosis, polychemotherapy is the first line of treatment although rituximab and radioimmunotherapy are evolving therapeutic options. Conclusion: In the majority of cases, the treatment of CBCL is straightforward. In aggressive forms, new therapies and biologic therapies may be of real interest. [ABSTRACT FROM AUTHOR]

Background: Chi t 1.01, a hemoglobin of the midge Chironomus thummi thummi, is a widespread environmental and occupational allergen. The aim of the present investigation was to identify and compare peptides involved in B-cell epitopes of Chi t 1.01 recognized by 15 human IgE sera, six murine monoclonal antibodies (mAbs), and a polyclonal rabbit antiserum. Methods: Synthetic peptides 19-21 amino acids long covering the whole Chi t 1.01-sequence were covalently coupled to activated paper disks as well as adsorbed to wells of immunoplates and used for enzyme-linked immunosorbent assay. For one epitope mapping, we used overlapping synthetic octapeptides with one amino-acid offset. Results: Peptides containing the amino acids 13-17, 23-29, and 40-50 were recognized by three of the mAbs, while three other mAbs reacting with none of the peptides obviously recognized conformational epitopes. Binding sites for rabbit antibodies and for human IgE antibodies were scattered over the whole molecule. The peptide 80-100 seemed to comprise at least one important IgE epitope. Depending on the method of antigen binding to the solid phase, differing results were obtained. Conclusions: Several linear epitopes in Chi t 1.01 are recognized by human IgE antibodies, by mAbs, and by polyclonal rabbit antibodies. In addition, the results indicate the presence of conformational epitopes. [ABSTRACT FROM AUTHOR]

B cells have an important pathogenic role in the development of type 1 diabetes in the non-obese diabetic ( NOD) mouse. We have previously reported that NOD mice display an increased percentage of TACIhigh-expressing B cells compared with C57 BL/6 mice and this trait is linked to chromosomes 1 and 8. In this paper the genetic association of the transmembrane activator, calcium modulator and cyclophilin ligand interactor ( TACI) trait was confirmed using double congenic NOD. B6C1/Idd22 mice. TACI ligation by a proliferation-inducing ligand ( APRIL) has been shown to influence plasma cell differentiation, immunoglobulin production and isotype switch. Hence, the functional consequence of the up-regulation of TACI on NOD B cells was analysed both in vitro and in vivo. NOD B cells stimulated with APRIL showed an enhanced plasma cell differentiation and class switch to IgG and IgA compared with B cells from C57 BL/6 mice. Moreover, flow cytometry analyses revealed that germinal centre B cells in NOD failed to down-regulate TACI. Availability of the TACI ligand B-cell activating factor ( BAFF) has been shown to be a limiting factor in the germinal centre reaction. In line with this, upon immunization with 4-hydroxy-3-nitrophenylacetyl hapten-conjugated hen egg lysozyme, NOD mice produced higher titres of low-affinity antibodies compared with C57 BL/6 mice. This observation was supported by the detection of increased levels of BAFF in NOD germinal centres after immunization compared with C57 BL/6 by immunofluorescence. Our results support the hypothesis that increased TACI expression on NOD B cells contributes to the pathogenesis of type 1 diabetes in the NOD mouse. [ABSTRACT FROM AUTHOR]