Unique endoscopic features of primary biliary diffuse large B-cell lymphoma: A case report with literature review (with video).

A 67-year-old man visited our hospital complaining of dark-colored urine and upper abdominal pain. Magnetic resonance cholangiopancreatography showed stricture of the distal bile duct, and contrast-enhanced computed tomography showed irregular thickening of the distal bile duct wall. However, no enlarged lymph nodes, pancreatic tumors, or other neoplastic lesions were apparent around the bile duct. Endoscopic ultrasonography and intraductal ultrasonography showed irregular thickening of the inner hypoechoic layer without the disappearance of the innermost thin hyperechoic layer. On the basis of these findings, we considered that the bile duct lesion was of non-epithelial origin. Thus, we repeatedly performed bile duct biopsies from the same site under fluoroscopy to obtain a sample of the submucosal tissue. The pathological diagnosis was diffuse large B-cell lymphoma, and the patient received systemic chemotherapy (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone). After six courses of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone, positron emission tomography-computed tomography showed the disappearance of 18-fluorodeoxyglucose uptake in the bile duct and endoscopic retrograde cholangiography showed improvement of the bile duct stricture. Endoscopic findings and repeated biopsies were useful in making the diagnosis of primary biliary diffuse large B-cell lymphoma.

B-cell-specific signatures reveal novel immunophenotyping and therapeutic targets for hepatocellular carcinoma.

BACKGROUND: Immunotherapy presents both promises and challenges in treating hepatocellular carcinoma (HCC) due to its complex immunological microenvironment. The role of B cells, a key part of the immune system, remains uncertain in HCC. AIM: To identify B-cell-specific signatures and reveal novel immunophenotyping and therapeutic targets for HCC. METHODS: Using the Tumor Immune Single-cell Hub 2 database, we identified B-cell-related genes (BRGs) in HCC. Gene enrichment analysis was performed to explore the possible collaboration between B cells and T cells in HCC. We conducted univariate Cox regression analysis using The Cancer Genome Atlas liver HCC collection dataset to find BRGs linked to HCC prognosis. Subsequently, least absolute shrinkage and selection operator regression was utilized to develop a prognostic model with 11 BRGs. The model was validated using the International Cancer Genome Consortium dataset and GSE76427. RESULTS: The risk score derived from the prognostic model emerged as an independent prognostic factor for HCC. Analysis of the immune microenvironment and cell infiltration revealed the immune status of various risk groups, supporting the cooperation of B and T cells in suppressing HCC. The BRGs model identified new molecular subtypes of HCC, each with distinct immune characteristics. Drug sensitivity analysis identified targeted drugs effective for each HCC subtype, enabling precision therapy and guiding clinical decisions. CONCLUSION: We clarified the role of B cells in HCC and propose that the BRGs model offers promising targets for personalized immunotherapy.

Long-Term Recurrence-Free Survival of an Elderly Patient With Diffuse Large B-cell Lymphoma in the Setting of Rituximab-Containing Therapy and a Natural History of Gastric Adenocarcinoma.

Diffuse large B-cell lymphoma (DLBCL) is a high-grade malignancy. We present a case of a 97-year-old female with gastric cancer and DLBCL in whom remission with rituximab-containing minimum chemotherapy was sustained for 10 years. As she had severe adverse effects, she refused further treatments for both tumors. Ten years after the initial treatment, examinations showed several tumors in the lungs, the right pleura, and the liver, as well as advanced gastric cancer. She eventually passed away, and the autopsy revealed that multiple tumors were not lymphoma, but adenocarcinoma. This case report is a valuable addition to the literature as it analyzes whether rituximab-containing minimum chemotherapy is effective for elderly DLBCL and delineates the natural history of gastric cancer.

Survival prediction in diffuse large B-cell lymphoma patients: multimodal PET/CT deep features radiomic model utilizing automated machine learning.

PURPOSE: We sought to develop an effective combined model for predicting the survival of patients with diffuse large B-cell lymphoma (DLBCL) based on the multimodal PET-CT deep features radiomics signature (DFR-signature). METHODS: 369 DLBCL patients from two medical centers were included in this study. Their PET and CT images were fused to construct the multimodal PET-CT images using a deep learning fusion network. Then the deep features were extracted from those fused PET-CT images, and the DFR-signature was constructed through an Automated machine learning (AutoML) model. Combined with clinical indexes from the Cox regression analysis, we constructed a combined model to predict the progression-free survival (PFS) and the overall survival (OS) of patients. In addition, the combined model was evaluated in the concordance index (C-index) and the time-dependent area under the ROC curve (tdAUC). RESULTS: A total of 1000 deep features were extracted to build a DFR-signature. Besides the DFR-signature, the combined model integrating metabolic and clinical factors performed best in terms of PFS and OS. For PFS, the C-indices are 0.784 and 0.739 in the training cohort and internal validation cohort, respectively. For OS, the C-indices are 0.831 and 0.782 in the training cohort and internal validation cohort. CONCLUSIONS: DFR-signature constructed from multimodal images improved the classification accuracy of prognosis for DLBCL patients. Moreover, the constructed DFR-signature combined with NCCN-IPI exhibited excellent potential for risk stratification of DLBCL patients.

Case report: Diffuse large B-cell lymphoma presenting as congestive heart failure in a cat.

Cardiac lymphoma is uncommon in cats and is rarely considered as a differential diagnosis for congestive heart failure. A 10-year-old neutered male domestic short-haired cat with clinical histories of feline immunodeficiency virus, diabetes mellitus, and congestive heart failure was humanely euthanized. Post-mortem evaluation demonstrated a massively infiltrative round cell neoplasm of the heart, resulting in CHF. Immunohistochemistry of neoplastic tissue was consistent with diffuse large B-cell lymphoma. This case demonstrates a peculiar presentation of cardiac diffuse large B-cell lymphoma, with chronic feline lentiviral infection possibly contributing to disease initiation and progression.

Primary breast lymphoma mimicking triple-negative breast cancer: a case report with clinical and pathological implications.

BACKGROUND: Primary breast lymphoma (PBL) is a rare type of extranodal lymphoma, the diagnostic process for which presents significant challenges owing to an overlap in clinical and pathological features with those observed in triple-negative breast cancer (TNBC). However, the current literature reveals a paucity of information regarding the ramifications of potential diagnostic errors, particularly in the context of emergent therapeutic strategies for TNBC. Thus, we present a unique report of a case of PBL. CASE PRESENTATION: A 76-year-old female with no past medical or family history presented to the hospital with the chief complaint of a mass in the right breast. Two masses were palpated in the right breast: one 56 mm mass (No. 1) located at 10 o'clock, and a 21 mm large, elastic, hard mass (No. 2) at 4 o'clock. Needle biopsy was performed only on the larger 56 mm mass (No. 1). The results showed invasive carcinoma that was negative for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor-2. The preoperative diagnosis was right breast cancer (T3N0M0 Stage IIB) of the TNBC subtype. The patient refused the preoperative chemotherapy recommended by the treatment team; therefore, right breast mastectomy and sentinel lymph-node biopsy were performed instead. The histopathological diagnosis of the first mass was diffuse large B-cell lymphoma (DLBCL); that of the second mass (No. 2) was an invasive breast carcinoma of no special type. Postoperative treatment consisted of endocrine therapy (letrozole) for breast cancer, while the DLBCL was treated with chemotherapy and three courses of intrathecal chemotherapy. At the time of this report, the patient is still living, and neither tumor had recurred in the 2 years following surgery. CONCLUSIONS: On rare occasions, PBL can preoperatively mimic TNBC. While this case did not lead to serious consequences, because surgery was eventually selected as the first therapy, clinicians should be aware that the diagnosis of PBL is challenging using only a core-needle biopsy and can often be misdiagnosed as TNBC.

Targeting RSV-neutralizing B cell receptors with anti-idiotypic antibodies.

Respiratory syncytial virus (RSV) causes lower respiratory tract infections with significant morbidity and mortality at the extremes of age. Vaccines based on the viral fusion protein are approved for adults over 60, but infant protection relies on passive immunity via antibody transfer or maternal vaccination. An infant vaccine that rapidly elicits protective antibodies would fulfill a critical unmet need. Antibodies arising from the VH3-21/VL1-40 gene pairing can neutralize RSV without the need for affinity maturation, making them attractive to target through vaccination. Here, we develop an anti-idiotypic monoclonal antibody (ai-mAb) immunogen that is specific for unmutated VH3-21/VL1-40 B cell receptors (BCRs). The ai-mAb efficiently engages B cells with bona fide target BCRs and does not activate off-target non-neutralizing B cells, unlike recombinant pre-fusion (preF) protein used in current RSV vaccines. These results establish proof of concept for using an ai-mAb-derived vaccine to target B cells hardwired to produce RSV-neutralizing antibodies.

Molecular characterization and biomarker identification in paediatric B-cell acute lymphoblastic leukaemia.

B-cell acute lymphoblastic leukaemia (B-ALL) is the most prevalent hematologic malignancy in children and a leading cause of mortality. Managing B-ALL remains challenging due to its heterogeneity and relapse risk. This study aimed to delineate the molecular features of paediatric B-ALL and explore the clinical utility of circulating tumour DNA (ctDNA). We analysed 146 patients with paediatric B-ALL who received systemic chemotherapy. The mutational landscape was profiled in bone marrow (BM) and plasma samples using next-generation sequencing. Minimal residual disease (MRD) testing on day 19 of induction therapy evaluated treatment efficacy. RNA sequencing identified gene fusions in 61% of patients, including 37 novel fusions. Specifically, the KMT2A-TRIM29 novel fusion was validated in a boy who responded well to initial therapy but relapsed after 1 year. Elevated mutation counts and maximum variant allele frequency in baseline BM were associated with significantly poorer chemotherapy response (p = 0.0012 and 0.028, respectively). MRD-negative patients exhibited upregulation of immune-related pathways (p < 0.01) and increased CD8+ T cell infiltration (p = 0.047). Baseline plasma ctDNA exhibited high mutational concordance with the paired BM samples and was significantly associated with chemotherapy efficacy. These findings suggest that ctDNA and BM profiling offer promising prognostic insights for paediatric B-ALL management.

Reduced Intensity Conditioning Prior Autologous Stem Cell Transplantation in Elderly DLBCL Patients.

High-dose chemotherapy (HDCT) followed by autologous stem cell transplantation (ASCT) is widely used in patients with diffuse large B-cell lymphoma. HDCT/ASCT is associated with increased morbidity in elderly/unfit patients. We retrospectively evaluated the use of reduced intensity conditioning in DLBCL patients. Our study included 146 patients aged 60 years and older treated at our institution between 2005 and 2019; 86 patients received standard intensity conditioning (SI group) with BEAM or TEAM (BCNU or thiotepa, etoposide, cytarabine, melphalan). Sixty patients received reduced intensity high-dose conditioning (RI group) with BM (BCNU, melphalan, 43.3%), TM (thiotepa, melphalan, 16.7%), BCNU or busulfan thiotepa (38.4%), or bendamustine melphalan (1.7%). Median follow-up was 62.4 months. We observed comparable toxicities in the SI and RI groups. The cumulative incidence of relapse at 3 years was higher in the RI group (30.8% vs. 23.4%, p = 0.034). There was no difference in nonrelapse mortality (NRM). In univariate analyses, SI vs. RI conditioning resulted in superior progression-free survival (PFS) (HR 1.80 CI 1.11-2.92, p = 0.017) but not in superior overall survival (OS) (HR 1.48 CI 0.86-2.56, p = 0.152). On multivariate analysis, we observed no difference in PFS (HR 0.74 CI 0.40-1.38, p = 0.345) and a trend toward better OS with RI conditioning (HR 0.45 CI 0.22-0.94, p = 0.032). Age 60-69 versus ≥ 70 years and remission prior to ASCT were the only factors predicting better PFS. Factors associated with better OS were RI conditioning, age 60-69 versus ≥ 70 years, ECOG 0 versus ≥ 1 performance status, bulky disease, and prior lines 1 versus ≥ 2. In conclusion, RI conditioning prior to ASCT may be feasible in elderly patients and led to a comparable outcome when corrected for several significant confounders.

TianTan Vaccinia Virus-based EBV vaccines targeting both latent and lytic antigens elicits potent immunity against lethal EBV challenge in humanized mice.

AbstractEpstein-Barr virus (EBV) infection has been related to multiple epithelial cancers and lymphomas. Current efforts in developing a prophylactic EBV vaccine have focused on inducing neutralizing antibodies. However, given the lifelong and persistent nature of EBV infection following primary infection, it is rationalized that an ideal vaccine should elicit both humoral and cellular immune responses targeting multiple stages of the EBV lifecycle. This study used a DNA vector and a TianTan vaccinia virus to express key EBV antigens, including BZLF1, EBNA1, EBNA3B, and gH/gL, to generate multi-antigen vaccines. The multi-antigen vaccine expressing all four antigens and the multi-antigen vaccine expressing BZLF1, EBNA1, and EBNA3B showed comparable protection effects and prevented 100% and 80% of humanized mice, respectively, from EBV-induced fatal B cell lymphoma by activating BZLF1, EBNA1, and EBNA3B specific T cell. The vaccine expressing lytic protein BZLF1 elicited stronger T cell responses and conferred superior protection compared to vaccines targeting single latent EBNA1 or EBNA3B. The vaccine solely expressing gH/gL exhibited no T cell protective effects in our humanized mice model. Our study implicates the potential of EBV vaccines that induce potent cellular responses targeting both latent and lytic phases of the EBV life cycle in the prevention of EBV-induced B cell lymphoma.

New generalized metric based on branch length distance to compare B cell lineage trees.

The B cell lineage tree encapsulates the successive phases of B cell differentiation and maturation, transitioning from hematopoietic stem cells to mature, antibody-secreting cells within the immune system. Mathematically, this lineage can be conceptualized as an evolutionary tree, where each node represents a distinct stage in B cell development, and the edges reflect the differentiation pathways. To compare these lineage trees, a rigorous mathematical metric is essential. Analyzing B cell lineage trees mathematically and quantifying changes in lineage attributes over time necessitates a comparison methodology capable of accurately assessing and measuring these changes. Addressing the intricacies of multiple B cell lineage tree comparisons, this study introduces a novel metric that enhances the precision of comparative analysis. This metric is formulated on principles of metric theory and evolutionary biology, quantifying the dissimilarities between lineage trees by measuring branch length distance and weight. By providing a framework for systematically classifying lineage trees, this metric facilitates the development of predictive models that are crucial for the creation of targeted immunotherapy and vaccines. To validate the effectiveness of this new metric, synthetic datasets that mimic the complexity and variability of real B cell lineage structures are employed. We demonstrated the ability of the new metric method to accurately capture the evolutionary nuances of B cell lineages.

Fibrin associated large B-cell lymphoma accidentally identified in a breast implant capsule: a molecular report of a rare entity.

Breast implant-associated (BIA) lymphoma is a rare malignancy, typically originating from T-cells; however, few cases of diffuse large B-cell lymphoma (LBCL) have been recently described. These cases share major features: Epstein-Barr virus positivity and a favorable prognosis with surgical intervention alone, hinting at a potential link to fibrin-associated LBCL (FA-LBCL). This study presents the first case of BIA-FA-LBCL in Italy and one of the few assessed from a molecular standpoint so far. We identified two pathogenic mutations in DNMT3A and a variant of uncertain significance (VUS) in JAK2. These findings suggest that dysfunctional epigenetic mechanisms and constitutive activation of the JAK-STAT pathway may underpin BIA-FA-LBCL lymphomagenesis. Finally, we summarized all the previously reported cases in alignment with the updated WHO-HAEM5 classification, shedding further light on the nature of this new entity. This report highlights the rarity of BIA-FA-LBCL and underscores the importance of comprehensive capsule sampling and reporting to national databases for accurate characterization and management of these lymphomas. The study supports the classification of BIA-FA-LBCL within the spectrum of FA-LBCL, emphasizing the need for further research to elucidate its molecular underpinnings and improve clinical outcomes.

Intravascular large B-cell lymphoma with respiratory failure diagnosed by random skin biopsy: A case report.

Intravascular large B-cell lymphoma (IVLBCL) typically involves nonspecific symptoms that complicate diagnosis. This report discusses the case of a 70-year-old man, who presented with dyspnea, fatigue, and weight loss that evolved into severe respiratory failure, diagnosed with IVLBCL via random skin biopsy. The initial improvement in respiratory symptoms was followed by coronavirus disease. Response to steroid therapy and elevated lactate dehydrogenase levels suggested IVLBCL, confirmed by a random skin biopsy. The combination chemotherapy of rituximab, cyclophosphamide, vincristine, doxorubicin, and prednisolone improved the respiratory condition. This case highlights the diagnostic challenges associated with IVLBCL and the crucial role of random skin biopsy.

Integrated multi-omics profiling reveals the ZZZ3/CD70 axis is a super-enhancer-driven regulator of diffuse large B-cell lymphoma cell-natural killer cell interactions.

Tumor immune microenvironment is crucial for diffuse large B-cell lymphoma (DLBCL) development. However, the mechanisms by which super-enhancers (SEs) regulate the interactions between DLBCL cells and tumor-infiltrating immune cells remains largely unknown. This study aimed to investigate the role of SE-controlled genes in regulating the interactions between DLBCL cells and tumor-infiltrating immune cells. Single-cell RNA-seq, bulk RNA-seq and H3K27ac ChIP-seq data were downloaded from the Heidelberg Open Research Data database and Gene Expression Omnibus database. HOMER algorithm and Seurat package in R were used for bioinformatics analysis. Cell proliferation and lactate dehydrogenase (LDH) release was detected by MTS and LDH release assays, respectively. Interaction between B cell cluster and CD8+ T cell and NK cell cluster was most obviously enhanced in DLBCL, with CD70-CD27, MIF-CD74/CXCR2 complex, MIF-CD74/CD44 complex and CCL3-CCR5 interactions were significantly increased. NK cell sub-cluster showed the strongest interaction with B cell cluster. ZZZ3 upregulated the transcription of CD70 by binding to its SE. Silencing CD70 in DOHH2 cells significantly promoted the proliferation of co-cultured NK92 cells and LDH release from DOHH2 cells, which was counteracted by ZZZ3 overexpression in DOHH2 cells. CD70 silencing combined with PD-L1 blockade promoted LDH release from DOHH2 cells co-cultured with NK92 cells. In conclusion, DLBCL cells inhibited the proliferation and killing of infiltrating NK cells by regulating ZZZ3/CD70 axis. Targeting ZZZ3/CD70 axis combined with PD-L1 blockade is expected to be a promising strategy for DLBCL treatment.

Double hit lymphoma: contemporary understanding and practices.

Double-hit lymphoma (DHL) is a high-risk subtype of large B-cell lymphoma, defined by concurrent rearrangements MYC and BCL2. The diagnosis is confirmed through histologic and immunophenotypic examination and fluorescence in situ hybridization (FISH) to demonstrate the rearrangements. DHL morphology ranges from DLBCL to high-grade B-cell lymphoma which can resemble Burkitt lymphoma and is almost always germinal center B-cell like (GCB). Prognosis is influenced by elevated lactate dehydrogenase (LDH), advanced stage, and extranodal involvement, among other factors. Treatment outcomes vary, but intensive chemotherapy regimens such as dose-adjusted EPOCH-R have shown the most promising results, though low-risk cases do occur and may do well with less intensive treatments. Recent therapeutic advances such as CAR-T cells and bispecific antibodies offer promise for patients with relapsed/refractory disease. This review synthesizes data from recent literature to provide a comprehensive analysis of the molecular underpinnings, diagnostic criteria, prognostic factors, and therapeutic strategies for DHL.

Impact of pre-infusion disease burden on outcomes in pediatric relapsed/refractory B-cell lymphoblastic leukemia following anti-CD19 CAR T-cell therapy.

Anti-CD19 chimeric antigen receptor (CAR) T-cell therapies have demonstrated high efficacy in pediatric patients with relapsed/refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL). Despite this success, the challenge of post-infusion relapse persists. In our study, we evaluate 116 children with R/R B-ALL who received anti-CD19 CAR T-cell therapy at our center. All patients were included in the response analysis and assessed for survival and toxicity. The CR rate was 98.3%, with 90.5% achieving minimal residual disease negative (MRD)- CR by day 28 (d28). The overall survival (OS) and event-free survival (EFS) were 69.3%±4.5% and 59.0%±4.6%, respectively, with a median follow-up duration of 47.9 months. The patients with pre-infusion MRD ≥ 1% was associated with lower 4-year OS (p = 0.006) and EFS (p = 0.027) comparing to those with MRD < 1%. The incidences of grade ≥ 3 cytokine release syndrome (CRS) and neurotoxicity were21.6 and 5.0%, respectively. Therefore, pre-infusion disease burden is a predictor of long-term outcome following anti-CD19 CAR T-cell therapy for pediatric R/R B-ALL.

Alterations in peripheral T-cell and B-cell subsets in the ankylosing spondylitis patients with gut inflammation.

AIM: This study investigates changes in immune cell subsets in peripheral blood of ankylosing spondylitis (AS) patients with colitis or terminal ileitis. It aims to explore the connection between changes in lymphocyte subsets and gut inflammation, providing insights for early detection. METHODS: Overall, 50 AS patients undergoing colonoscopy were enrolled. Flow cytometry was employed to analyze lymphocyte subsets, including T and B cells, in peripheral blood. Disease activity was assessed using CRP, ESR, BASDAI, ASDAS-CRP, and ASDAS-ESR. RESULTS: Compared to AS patients without gut inflammation, those with colorectal inflammation showed a significant increase in total T cells (p < .05), an increase in exhausted CD4+ T cells (p < .05), and a decrease in Th2 cells and total Tc cells (p < .05). Notably, in AS patients with terminal ileitis, there was an increase in total B cells and classic switched B cells (p < .05), with a decrease in double-positive T cells (p < .05). However, no significant differences were observed in the distribution of Tfh-cell subpopulations (Tfh1, Tfh2, Tfh17) and Tc-cell subpopulations (Tc1, Tc2, Tc17) between AS patients with either colorectal inflammation or terminal ileitis (p > .05). We explored the relationship between disease activity scores, ESR, CRP, and lymphocyte subsets, but found no statistically significant correlation between them. CONCLUSION: Distinct immune patterns may exist in AS with different types of intestinal inflammation. Colitis in AS is primarily characterized by a significant increase in exhausted CD4+ T cells, along with a decrease in Th2 cells. In contrast, terminal ileum inflammation in AS is marked by an increase in total B cells and classic switched B cells. These findings offer new insights for early detection and therapeutic intervention.

The negative effects of extracellular vesicles in the immune system.

Immunity is a critical self-defense mechanism of the human body, wherein immune cells and immune molecules play a crucial role. Extracellular vesicles (EVs), derived from immune cells or other cells, play a significant role in tumors, autoimmune diseases and other immune-related disorders by serving as carriers and facilitating intercellular communication through the transfer of cargoes. Numerous studies have revealed that EVs can exacerbate disease development by modulating immune responses. Therefore, this paper focuses on the effects of EVs on the number, activity and function of different types of immune cells and the release of immune molecules (such as cytokines, antigens, antibodies, etc) in various diseases, as well as the roles of EVs associated with different types of immune cells in various diseases. We aim to provide a comprehensive review of the negative effects that EVs play in the immune system to provide more ideas and strategies for the management of clinical immune diseases.

Genomic comparison between Mycobacterium bovis and Mycobacterium microti and in silico analysis of peptide-based biomarkers for serodiagnosis.

In recent years, there has been an increase in the number of reported cases of Mycobacterium microti infection in various animals, which can interfere with the ante-mortem diagnosis of animal tuberculosis caused by Mycobacterium bovis. In this study, whole genome sequencing (WGS) was used to search for protein-coding genes to distinguish M. microti from M. bovis. In addition, the population structure of the available M. microti genomic WGS datasets is described, including three novel Belgian isolates from infections in alpacas. Candidate genes were identified by examining the presence of the regions of difference and by a pan-genome analysis of the available WGS data. A total of 80 genes showed presence-absence variation between the two species, including genes encoding Proline-Glutamate (PE), Proline-Proline-Glutamate (PPE), and Polymorphic GC-Rich Sequence (PE-PGRS) proteins involved in virulence and host interaction. Filtering based on predicted subcellular localization, sequence homology and predicted antigenicity resulted in 28 proteins out of 80 that were predicted to be potential antigens. As synthetic peptides are less costly and variable than recombinant proteins, an in silico approach was performed to identify linear and discontinuous B-cell epitopes in the selected proteins. From the 28 proteins, 157 B-cell epitope-based peptides were identified that discriminated between M. bovis and M. microti species. Although confirmation by in vitro testing is still required, these candidate synthetic peptides containing B-cell epitopes could potentially be used in serological tests to differentiate cases of M. bovis from M. microti infection, thus reducing misdiagnosis in animal tuberculosis surveillance.