High Plasma Cell Research Articles

Identification and quantification of immune infiltration landscape on therapy and prognosis in left- and right-sided colon cancer

BackgroundThe left-sided and right-sided colon cancer (LCCs and RCCs, respectively) have unique molecular features and clinical heterogeneity. This study aimed to identify the characteristics of immune cell infiltration (ICI) subtypes for evaluating prognosis and therapeutic benefits.MethodsThe independent gene datasets, corresponding somatic mutation and clinical information were collected from The Cancer Genome Atlas and Gene Expression Omnibus. The ICI contents were evaluated by “ESTIMATE” and “CIBERSORT.” We performed two computational algorithms to identify the ICI landscape related to prognosis and found the unique infiltration characteristics. Next, principal component analysis was conducted to construct ICI score based on three ICI patterns. We analyzed the correlation between ICI score and tumor mutation burden (TMB), and stratified patients into prognostic-related high- and low- ICI score groups (HSG and LSG, respectively). The role of ICI scores in the prediction of therapeutic benefits was investigated by "pRRophetic" and verified by Immunophenoscores (IPS) (TCIA database) and an independent immunotherapy cohort (IMvigor210). The key genes were preliminary screened by weighted gene co-expression network analysis based on ICI scores. And they were further identified at various levels, including single cell, protein and immunotherapy response. The predictive ability of ICI score for prognosis was also verified in IMvigor210 cohort.ResultsThe ICI features with a better prognosis were marked by high plasma cells, dendritic cells and mast cells, low memory CD4+ T cells, M0 macrophages, M1 macrophages, as well as M2 macrophages. A high ICI score was characterized by an increased TMB and genomic instability related signaling pathways. The prognosis, sensitivities of targeted inhibitors and immunotherapy, IPS and expression of immune checkpoints were significantly different in HSG and LSG. The genes identified by ICI scores and various levels included CA2 and TSPAN1.ConclusionThe identification of ICI subtypes and ICI scores will help gain insights into the heterogeneity in LCC and RCC, and identify patients probably benefiting from treatments. ICI scores and the key genes could serve as an effective biomarker to predict prognosis and the sensitivity of immunotherapy.

Evaluation of an innovative new method for quantitation of plasma cells on CD138 immunohistochemistry

AimTo compare the frequently used CD138 immunohistochemistry-based method of plasma cell quantitation, to a proposed new method, using interobserver and intraobserver concordance parameters.MethodsArchival CD138 immunohistochemically stained slides made from paraffin-embedded...

MP66-19 SURVEY OF B AND PLASMA CELLS IN BLADDER CANCER

You have accessJournal of UrologyBladder Cancer: Basic Research & Pathophysiology III (MP66)1 Sep 2021MP66-19 SURVEY OF B AND PLASMA CELLS IN BLADDER CANCER Yuanshuo Wang, Jorge Daza, Giuliana Magri, Emilie Grasset, Kristin Beaumont, Adam Farkas, Li Wang, Rachel Brody, Reza Mehrazin, Peter Wiklund, Robert Sebra, Jun Zhu, Matthew Galsky, Nina Bhardwaj, John Sfakianos, and Amir Horowitz Yuanshuo WangYuanshuo Wang More articles by this author , Jorge DazaJorge Daza More articles by this author , Giuliana MagriGiuliana Magri More articles by this author , Emilie GrassetEmilie Grasset More articles by this author , Kristin BeaumontKristin Beaumont More articles by this author , Adam FarkasAdam Farkas More articles by this author , Li WangLi Wang More articles by this author , Rachel BrodyRachel Brody More articles by this author , Reza MehrazinReza Mehrazin More articles by this author , Peter WiklundPeter Wiklund More articles by this author , Robert SebraRobert Sebra More articles by this author , Jun ZhuJun Zhu More articles by this author , Matthew GalskyMatthew Galsky More articles by this author , Nina BhardwajNina Bhardwaj More articles by this author , John SfakianosJohn Sfakianos More articles by this author , and Amir HorowitzAmir Horowitz More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002106.19AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Tumor infiltrating B cells in bladder cancer (BCa) have been associated with cancer invasion, but little is understood regarding their role in the tumor microenvironment. In this study, we analyzed single cell sequencing data from tumor (n=19) and PBMC (n=20) samples from 26 BCa patients to profile the heterogeneity of B cells and plasma cells (PCs). METHODS: Single cell data was imported into R (v4.03) using the SingleCellExperiment package, and outliers in mitochondrial gene percentage, library size, or detected genes were discarded. Normalization, deconvolution, and library size adjustment were done using the scran and batchelor R packages. Trajectory analysis was done using the Monocle R package. RESULTS: We identified 3,158 CD45+ naïve, non-switched memory (NSM), and switched memory (SM) B cells and PCs according to their marker gene expression (Fig 1). The majority of naïve and memory B cells were from PBMC, whereas plasma cells were primarily from tumor. To understand the heterogeneity of PCs, we performed clustering and trajectory analysis on 1,411 PCs and identified eight clusters (Fig 2A). Though most clusters consisted mainly of tumor cells, clusters 7 is almost exclusively from PBMC and is at the beginning of the pseudotime trajectory (Fig 2A). Its lower expression of PC markers such as MZB1, XBP1, and immunoglobulin genes suggest that it’s at an earlier stage of PC maturation (Fig 2A). Clusters 1, 6, and 8 contain PCs likely representative of mature plasmablasts, as they are at the end of the pseudotime trajectory and express high levels PC markers and immunoglobulin genes (Fig 2A). Lastly, cluster 4 upregulates expression of HLA-DP, HLA-DQ, and HLA-DR genes further on the pseudotime trajectory (Fig 2B). CONCLUSIONS: From our survey of B cells and PCs from a large single cell BCa cohort, we observed the majority of PCs to be found in the tumor. Tumor PCs demonstrate a high degree of heterogeneity, encompassing at least an early stage subset, a more mature plasmablast-like subset, and another subset with upregulated HLA expression with potential for T-cell stimulatory function. Source of Funding: institutional funds © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e1137-e1137 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Yuanshuo Wang More articles by this author Jorge Daza More articles by this author Giuliana Magri More articles by this author Emilie Grasset More articles by this author Kristin Beaumont More articles by this author Adam Farkas More articles by this author Li Wang More articles by this author Rachel Brody More articles by this author Reza Mehrazin More articles by this author Peter Wiklund More articles by this author Robert Sebra More articles by this author Jun Zhu More articles by this author Matthew Galsky More articles by this author Nina Bhardwaj More articles by this author John Sfakianos More articles by this author Amir Horowitz More articles by this author Expand All Advertisement Loading ...

In Silico Analysis of the Longevity and Timeline of Individual Germinal Center Reactions in a Primary Immune Response.

Germinal centers (GCs) are transient structures in the secondary lymphoid organs, where B cells undergo affinity maturation to produce high affinity memory and plasma cells. The lifetime of GC responses is a critical factor limiting the extent of affinity maturation and efficiency of antibody responses. While the average lifetime of overall GC reactions in a lymphoid organ is determined experimentally, the lifetime of individual GCs has not been monitored due to technical difficulties in longitudinal analysis. In silico analysis of the contraction phase of GC responses towards primary immunization with sheep red blood cells suggested that if individual GCs had similar lifetimes, the data would be consistent only when new GCs were formed until a very late phase after immunization. Alternatively, there could be a large variation in the lifetime of individual GCs suggesting that both long and short-lived GCs might exist in the same lymphoid organ. Simulations predicted that such differences in the lifetime of GCs could arise due to variations in antigen availability and founder cell composition. These findings identify the potential factors limiting GC lifetime and contribute to an understanding of overall GC responses from the perspective of individual GCs in a primary immune response.

Clinical Characteristics and Risk Factors for Pleural Effusion in Patients with Multiple Myeloma.

PurposePleural effusion (PE) is prevalent in “real-life” populations of multiple myeloma (MM), a common hematologic malignancy. Development of PE likely has prognostic implications. The aim of this study was to investigate the characteristics and identify risk factors for occurrence of PE in MM.Patients and MethodsWe reviewed electronic medical records of 907 patients diagnosed with MM.ResultsIncidence of PE in MM patients was 42.7%. Small and bilateral PE in most cases. PE developed in all MM subtypes, the median time from diagnosis of multiple myeloma to pleural effusion was 6.8 months (range 0.8–33.6 months). Patients with PE showed worse survival than those without PE (unadjusted hazard ratio with 95% confidence interval: 2.249 [1.774–2.852]). No difference in survival was found between patients with small PE and those with moderate to large PE (unadjusted HR, 1.402; 95% CI, 1.037–1.896). Plasma cell proportion (OR, 1.373; 95% CI, 1.153–1.634; P = 0.009) and amyloidosis (OR, 1.791; 95% CI, 1.408–2.279; P = 0.024) were risk factors for the occurrence of PE at the initial diagnosis of MM. Plasma cell proportion (OR, 1.853; 95% CI, 1.451–2.368; P = 0.038), pneumonia (OR, 1.309; 95% CI, 1.143–1.498; P = 0.008) and heart failure (OR, 1.815; 95% CI, 1.387–2.374; P = 0.031) were risk factors for the occurrence of PE at relapse of MM.ConclusionThe incidence of PE in MM patients is notable and PE can occur in all MM subtypes. PE indicates a poor prognosis, even small amounts of effusion. PE is a problem worthy of attention, especially in patients with high plasma cell proportion, amyloidosis or complicated with pneumonia and heart failure.

Myeloma Cell Associated Therapeutic Protein Discovery Using Single Cell RNA-Seq Data

Multiple myeloma (MM) is a hematological cancer of the antibody-secreting plasma cells. Despite therapeutic advancements, MM remains incurable due to high incidence of drug-resistant relapse. In recent years, targeted immunotherapies, which take advantage of the immune system's cytotoxic defenses to specifically eliminate tumor cells expressing certain cell surface and intracellular proteins have shown promise in combating this and other B cell hematologic malignancies. A major limitation in the development of these therapies lies in the discovery of optimal candidate targets, which require both high expression in tumor cells as well as stringent tissue specificity. In an effort to identify potential myeloma-specific target antigens, we performed an unbiased search for genes with specific expression in plasma and/or B cells using single-cell RNA-sequencing (scRNAseq) of 53 bone marrow samples taken from 42 patients. By comparing >40K plasma cells to >97K immune cells across our cohort, we were able to identify a total of 181 plasma cell-associated genes, including 65 that encode cell-surface proteins and 116 encoding intracellular proteins. Of particular interest is that the plasma cells from each patient were shown to be transcriptionally distinct with unique sets of genes expressed defining each patient's malignant plasma cells. Using pathway enrichment analysis, we found significant overrepresentation of cellular processes related to B-Cell receptor (BCR) signaling, protein transport, and endoplasmic reticulum (ER) stress, involving genes such as DERL3, HERPUD1, PDIA4, PDIA6, RRBP1, SSR3, SSR4, TXNDC5, and UBE2J1. To note, our strategy successfully captured several of the most promising MM therapeutic targets currently under pre-clinical and clinical trials, including TNFRSF17(BCMA), SLAMF7, and SDC1 (CD138). Among these, TNFRSF17 showed very high plasma cell expression, with concomitant sharp exclusion of other immune cell types. To ascertain tissue specificity of candidate genes outside of the bone marrow, we analyzed gene and protein expression data from the Genotype-Tissue Expression (GTEx) portal and Human Protein Atlas (HPA). We found further support for several candidates (incl. TNFRSF17,SLAMF7, TNFRSF13B (TACI), and TNFRSF13C) as being both exclusively and highly expressed in lymphoid tissues. While several surface candidates were not found to be lymphocyte-restricted at the protein level, they remain relevant considerations as secondary targets for bi-specific immunotherapy approaches currently under development. To further investigate potential combinatorial targeting, we examine sample-level patterns of candidate co-expression and mutually-exclusive expression using correlation analysis. As the majority of our detected plasma cell-specific genes encode intracellular proteins, we investigated the potential utility of these epitopes as therapeutic targets via MHC presentation. Highly expressed candidates include MZB1, SEC11C, HLA-DOB, POU2AF1, and EAF2. We analyzed protein sequences using NetMHC and NETMHCII to predict high-affinity peptides for common class-I and class-II HLA alleles. To correlate MHC allelic preference with candidate expression in our cohort, we performed HLA-typing for 29 samples using Optitype. To support our scRNAseq-driven findings, we cross-referenced gene expression data with 907 bulk RNA-sequencing samples, including 15 from internal studies and 892 from the Multiple Myeloma Research Foundation (MMRF), as well as bulk global proteomics data from 4 MM cell lines (TIB.U266, RPMI8226, OPM2, MM1ST) and 4 patients. We see consistent trends across both cohorts, with high positive correlation (Pearson R ranging between 0.60 and 0.99) for a majority of genes when comparing scRNA and bulk RNA expression in the same samples. Our experimental design and analysis strategies enabled the efficient discovery of myeloma-associated therapeutic target candidates. In conclusion, this study identified a set of promising myeloma CAR-T targets, providing novel treatment options for myeloma patients. Disclosures Goldsmith: Wugen Inc.: Consultancy. DiPersio:Magenta Therapeutics: Membership on an entity's Board of Directors or advisory committees.

A global antiB cell strategy combining obinutuzumab and daratumumab in severe pediatric nephrotic syndrome.

BackgroundSteroid-sensitive nephrotic syndrome (SSNS) is, in most patients, a chronic disease with 80% experiencing at least one relapse after first flare. B cell depletion using rituximab is effective in preventing relapse in steroid-dependent (SDNS) patients but fails to maintain long-term remission following B cell recovery, possibly due to development of autoreactive long-lived plasma cells. We investigated sequential combination of antiCD20 antibody targeting all B cell subsets, and antiCD38 antibody with high plasma cell cytotoxicity in patients with uncontrolled SDNS after failure of one or several attempts at B cell depletion.MethodsFourteen patients with median disease duration 7.8 years received 1000 mg/1.73 m2 obinutuzumab followed by 1000 mg/1.73 m2 daratumumab 2 weeks later. Oral immunosuppression was discontinued within 6 weeks, and biological monitoring performed monthly until B cell recovery.ResultsMedian age at treatment was 11.0 [IQR 10.4–14.4] years. B cell depletion was achieved in all patients, and B cell reconstitution occurred in all at median 9.5 months after obinutuzumab injection. After median follow-up 20.3 months (IQR 11.5–22.6), 5/14 patients relapsed including 4 within 100 days following B cell repletion. Relapse-free survival was 60% at 24 months from obinutuzumab infusion. Mild infusion reactions were reported in 3/14 patients during obinutuzumab and 4/14 during daratumumab infusions. Mild transient neutropenia (500–1000/mm3) occurred in 2/14 patients. Intravenous immunoglobulins were given to 12/14 patients due to hypogammaglobulinemia. Low IgA and IgM levels were noted in 8 and 14 patients, respectively. No severe infection was reported.ConclusionGlobal antiB cell strategy combining obinutuzumab and daratumumab induces prolonged peripheral B cell depletion and remission in children with difficult-to-treat SDNS.Electronic supplementary materialThe online version of this article (10.1007/s00467-020-04811-0) contains supplementary material, which is available to authorized users.

Plasma Cell Infiltration on Histopathological Samples of Chronic Bone and Joint Infections due to Cutibacterium acnes: A series of 21 Cases.

Introduction: Histopathological definition of bone and joint infection (BJI) is based on Mirra's criterion (≥ 5 polymorphonuclears (PMNs) per field in 5 high power fields (HPFs)). However, this definition does not seem appropriate for chronic BJIs caused by slow-growing germs such as Cutibacterium acnes (C. acnes). The aim of this study was to confirm that Mirra's criterion is not adequate for diagnosis of BJIs due to C. acnes. The second objective was to determine if plasma cell infiltration could be useful for the diagnosis of chronic BJIs due to C. acnes.Methods: We retrospectively selected 25 consecutive patients from 2009 to 2013 with chronic BJIs due to C. acnes. Histological analysis was performed on the 21 cases with at least two C. acnes positive cultures. In addition of Mirra's criterion, the number of plasma cells (≥5 plasma cells/5 HPFs, defined as “CRIOAc Lyon's criterion”) was implemented in the histopathological analysis. Patients were defined as infected, if at least one of the two criteria were present.Results: According to Mirra's and CRIOAc Lyon's criteria, positive histopathology was observed in 12 (57.1%) and 15 (71.4%) cases respectively. Considering the 9 cases with negative Mirra's criterion, high plasma cell infiltration (≥5 plasma cells per field/5 HPFs) was observed in 5 cases (55.6%), and low plasma cells infiltration (2-5 plasma cells per field/5 HPFs) was observed in 4 other cases (44.4%).Conclusions: Adding CRIOAc Lyon's criterion to Mirra's criterion might restore some histopathological diagnosis of chronic BJIs due to C. acnes when a chronic BJI is clinically suspected.

Gene Expression-Based Immune Cell Infiltration Analyses of Prostate Cancer and Their Associations with Survival Outcome.

Prostate cancer is the second most common cancer and the fifth cause of cancer death in males. Currently, there are no effective therapies for prostate cancer yet, and the status of treatment remains severe. In this study, we analyzed the composition of tumor-infiltrating immune cells (TIICs) in prostate cancer and paracancerous samples based on the gene expression profiles using CIBERSORT. Calculation of the TIIC subset proportions in 52 paired prostate cancer and paracancerous samples showed that their proportions were similar in intergroup and varied in intragroup. Compared with the paracancerous samples, the proportion of M0 macrophages was significantly increased in prostate cancer samples. Cox regression analysis using the TIIC subpopulations as continuous variables revealed that high plasma cell proportion was associated with poor 3-year Disease-Free Survival (DFS) in prostate cancer (hazard ratios = 1.8e-76, p = 0.001). Moreover, three immune clusters, which presented distinct prognosis, were identified using hierarchical clustering analysis based on the proportions of TIIC subpopulations. Among them, cluster 1 had superior 3-year DFS, while cluster 3 showed inferior 3-year DFS (p = 0.025). In summary, our research provided a comprehensive analysis on the TIIC composition in prostate cancer and suggested that both plasma cells and different cluster patterns were associated with the prostate cancer prognosis, which should be helpful for the clinical surveillance and treatment of prostate cancer.

Bortezomib induction prior to autologous hematopoietic cell transplantation (AHCT) for newly diagnosed light chain amyloidosis (AL): A study of 426 patients.

8515 Background: AL is a clonal plasma cell (PC) disorder causing multiorgan dysfunction from amyloid fibril deposition. While bortezomib (B) induction has been used prior to AHCT recently, AHCT without prior induction has been a common practice. The primary objective of this study was to compare outcomes of AL patients who proceeded to AHCT without induction to those receiving pre-AHCT induction with B. Methods: Outcomes of 426 systemic AL AHCT recipients between 2014-2018 reported to the Center for International Blood and Marrow Transplant Research (CIBMTR) were reviewed. Patients receiving induction with therapy other than B, AHCT occurring > 9 months after diagnosis, no documented AL end-organ involvement, myeloma-defining events and conditioning other than melphalan (MEL) monotherapy were excluded. Multivariate analysis (MVA) was conducted to identify prognostic factors associated with relapse, PFS and overall survival (OS). Results: 286 patients received B induction therapy vs 140 patients receiving no induction. Age, gender, number and type of organs involved, and AL AHCT center volume were similar between the groups. Patients receiving induction had greater PC burden compared with no induction (PC ≥ 10%, 41% vs 11%, p < 0.01). Induction was B, cyclophosphamide and dexamethasone (D) in 83% followed by B, lenalidomide and D (10%) or B+D (7%). Median follow-up was 24.9 months. At 2 years, B induction vs. no induction was associated with 13% (95% CI 10-17%) vs 22% (95% CI 15-30%) relapse risk (p = 0.03); 83% (95% CI 79-87%) vs 74% (95% CI 66-81%) PFS (p = 0.04); 93% (95% CI 90-95%) vs 94% (95% CI 89-97%) OS (p = 0.7). On MVA, the B induction group had improved PFS (HR 0.46, 95% CI 0.3-0.7, p < 0.001) with similar OS (HR 0.6, 95% CI 0.3-1.2, p = 0.1) compared with no induction. Creatinine < 2 mg/dl (HR 0.55, 95% CI 0.3-0.9, p = 0.02) and Karnofsky score ≥90 (HR 0.51, 95% CI 0.33-0.78, p < 0.01) were also associated with improved PFS. MEL dose < 180 mg/m2 was associated with inferior PFS (HR 2.17, 95% CI 1.31-3.61, p < 0.01) and OS (HR 3.6, 95% CI 1.5-8.6, p < 0.01). No deaths were seen in the first 100 days post-AHCT. At last follow-up, 32 deaths occurred, 26 (81%) due to AL. Conclusions: Compared with prior CIBMTR analyses, B induction use has increased in AL AHCT recipients and a higher PC burden was the only clinical determinant. Furthermore, B induction was associated with lower relapse and improved PFS at 2 years with no OS difference despite higher proportion of patients with > 10% PC, which has been associated with poor outcomes.

High rate of profound clonal and renal responses with daratumumab treatment in heavily pre-treated patients with light chain (AL) amyloidosis and high bone marrow plasma cell infiltrate.

Daratumumab demonstrated activity in the treatment of AL amyloidosis in two recently concluded phase II clinical trials in relapsed and refractory patients. Its role in upfront therapy is under evaluation in a phase III study. In this report we evaluated the safety and efficacy of 28-day cycles of daratumumab (single agent or combined with bortezomib or lenalidomide) in 72 previously treated patients with multiple myeloma and AL amyloidosis. Fifty (69%) were refractory to the last line of therapy. After eight infusions of daratumumab, 59 patients (82%) achieved a hematologic response, with 12 (16%) complete responses (CRs) and 30 (42%) very good partial responses (VGPRs). After 16 infusions, the quality of response improved with 22 patients (30%) achieving CR and 21 (29%) attaining VGPR. Cardiac response was observed in 11 of 37 evaluable patients (29%) and renal response in 23 of 38 patients (60%). Daratumumab is highly effective in heavily pretreated patients with relapsed/refractory AL amyloidosis and high bone marrow plasma cell burden. Renal responses, which are usually rare in this setting, were frequently observed.

Increased Plasma Cells and Decreased B-cells in Tumor Infiltrating Lymphocytes are Associated with Worse Survival in Lung Adenocarcinomas.

Clinical significance of tumor-infiltrating plasma cells and B-cells in lung adenocarcinoma is not well known. CD3, CD20 and MUM1 immunostains were performed on representative tumor blocks selected from 120 consecutive lung adenocarcinoma cases treated by surgical resection at Mayo Clinic Rochester. CD3+ T-cells, CD20+ B-cells, and MUM1+ plasma cells were enumerated separately in the intraepithelial (IE) compartment and the stroma (ST) by digital image analyses using whole sections. Measured tumor-infiltrating plasma cells and B-cells were correlated with patient's overall survival (OS) using Cox proportional hazards analysis. Median age of patients was 69 years (range, 46-91 years) and 52 were male. Median numbers (interquartile range) of CD20+ B-cells per 1mm2 of tumor area (IE plus ST) and IE compartment within tumor area were 590 (224-1276) and 101 (38-109), respectively; the corresponding numbers of MUM1+ plasma cells were 298 (180-605), and 67 (22-145), respectively. The proportion of MUM1+ plasma cell among all TILs (MUM1+ cells/[CD3+ cells +CD20+ cells+MUM1+ cells] × 100) ranged 1%-59% (median13%) in the tumor area and showed a significant association with OS by univariate Cox analysis (negative correlation with hazard ratio (HR)=12.50 [95% confidence interval (CI), 1.75-89.27]). There was a significant association between IE CD20+ B-cells and the patient's OS in univariate analysis (positive correlation with HR=0.81 [95% CI, 0.68-0.96]). Both parameters remained significant by multivariate analysis. High plasma cell % among TILs in the tumor area and low IE B-cell count were associated with worse prognosis in lung adenocarcinoma patients.

Plasma cell dyscrasia behavior in a referral hospital in southern Colombia: younger, clinically and paraclinically worse than reported

Objectives: Plasma cell dyscrasias are diseases characterized by clonal proliferation and accumulation of cells producing monoclonal immunoglobulins. These diseases have not been studied in our region and we don’t know if their behavior is similar to that reported in the literature. That’s why we evaluated multiple characteristics in southern Colombia. Methods: analytical cross-sectional study of patients with confirmed diagnosis of a plasma cell dyscrasias were included. Results: 60 patients included in our study, 65% were men, with an average age of 58.8 years (CI 96% 55.8 - 61.93). Bone pain was the most frequent symptom (88%). The most frequent dyscrasia was multiple myeloma and in these patients we found a high percentage of hemoglobin less than 10 mg/dl, creatinine greater than 2 mg/dl and serum calcium higher than 11 mg/dl (77%, 38% and 37 %, respectively). Half of the patients had a time course of symptoms greater than 4 months and 43% had plasma cells in bone marrow greater than 60%. 65% of patients had elevated levels of serum B2-microglobulin (> 5.5 mg/L) and in-hospital mortality was 15%. We found a statistically significant association between mortality and gender (PR 6.5) and between mortality and hemoglobin (p = 0.039). Conclusion: Patients with plasma cell dyscrasia in southern Colombia are younger, consult late, in an advanced stage of their disease, with greater renal damage, hypercalcemia and anemia than reported in the literature, also a high tumor burden due to high plasma cell infiltration into bone marrow and high values of serum B2-microglobulin

Histological characterization of the lingual tonsils of the one-humped camel (Camelus dromedarius).

Tonsils are located in the entrance of digestive and respiratory tracts forming Waldeyer's ring that reacts against ingested or inhaled antigens. On occasion, tonsils may be a site of entry and replication for some pathogens. The lingual tonsils are a main constituent of the Waldeyer's ring. Despite the immunological importance of the lingual tonsils, there is limited information about their structure in the one-humped camel. The lingual tonsils of 10 clinically healthy male camels (3-25 years) were collected and studied macroscopically and microscopically. Lingual tonsils were localized at the root of the tongue of camels of all ages in the form of several spherical macroscopic nodules protruding into the oropharynx. Each nodule possesses a single central crypt, covered with keratinized stratified squamous epithelium without any M cells and surrounded with an incomplete capsule. Each tonsillar crypt was lined with stratified squamous non-keratinized epithelium with lymphocytic infiltration forming patches of lymphoepithelium or reticular epithelium. Secondary lymphoid nodules extended under the apical epithelium. The interfollicular areas had diffused lymphocytes. Among these lymphocytes, high endothelial venules, macrophages, dendritic cells and plasma cells were observed. The organization of camel lingual tonsils in isolated units with separate crypts increases the surface area exposed to antigen. The present findings indicate a sustained immunological role of the lingual tonsils throughout the life of the one-humped camel.

Monoclonal immunoglobulin mediates complement activation in monoclonal gammopathy associated-C3 glomerulonephritis

BackgroundC3 glomerulonephritis (C3GN) is a rare disease caused by inherited or acquired complement alternative pathway (CAP) dysregulation, which could also be secondary to monoclonal gammopathy of undetermined significance (MGUS). Herein, we described a patient presenting with C3GN and monoclonal gammopathy, and the pathogenic association between the two diseases was further explored in vitro.Case presentationA 76-year-old Chinese man presented with low serum C3 level, haematuria and nephrotic syndrome, and experienced rapid worsening of renal function over a period of 10 months. His serum and urine immunofixation electrophoresis both revealed a monoclonal IgGλ. A bone marrow puncture showed plasma cell dyscrasias with the highest plasma cell count of 5.25%. Kidney biopsy showed the presence of C3 glomerulonephritis, with exclusive deposits of C3 visible on immunofluorescence, a membranoproliferative pattern on light microscopy and electron dense deposits in sub-epithelial, intramembranous, sub-endothelial and mesangial regions by electron microscopy. The patient was positive for C3 nephritic factor (C3NeF) activity and anti-CFH autoantibodies, and all became negative during disease remission. The anti-CFH autoantibodies purified from the patient’s plasma exchange fluids were proven to be a monoclonal IgGλ, and could inhibit CFH binding to C3b and accelerate the formation of C3 convertase indirectly by interfering with the formation-impeding activity of CFH. No deficiency of candidate genes, especially variants in CFH, was detected in our patient. Based on the pathological and laboratory findings, the diagnosis of monoclonal gammopathy of renal significance (MGRS)-associated C3GN was finally made.ConclusionsThis is the first demonstration that intact monoclonal immunoglobulin (IgGλ) could act as an anti-CFH antibody and lead to MGRS-associated C3GN by activating the CAP.

The JAK1/2 Inhibitor Ruxolitinib Downregulates CXCL12 Secretion from Bone Marrow Stromal Cells and M2 Macrophage Polarization in Multiple Myeloma

Introduction: The JAKSTAT pathway plays a critical role in the regulation of hematopoietic pathways and immunological cytokine signaling. The JAK pathway is also involved in tumor cell proliferation and drug resistance in multiple myeloma (MM). Thus, inhibition of the JAK pathway should be a potentially effective strategy for treating MM patients. B7-H3 is an immune checkpoint protein in the B7 superfamily and has been shown overexpressed in several tumors. Immune checkpoint blockade may suppress tumor progression or enhance anti-tumor immune responses. In this study, we investigated the effects of the JAK1/2 inhibitor ruxolitinib (Rux) on B7-H3 in MM. Materials and Methods: Bone marrow mononuclear cells (BMMCs) were collected from MM patients after obtaining IRB approval. Single-cell suspensions were prepared from human MM LAGλ-1A xenografts which had been grown in severe combined immunodeficient mice. HS-5 stromal and SUP-T1 T cells were purchased from ATCC. The cells were cultured and treated with or without RUX and then subjected to qRT-PCR, flow cytometric analysis, and western blot analysis. For qRT-PCR, total RNA was extracted and applied to cDNA synthesis, followed by qPCR. Gene expression was analyzed in MM BMMCs alone or co-cultured with stromal cells or T cells with or without Rux treatment (1μM) in vitro. Results: We identified increased B7-H3 expression in MMBMMCs from patients with progressive disease (PD) patients compared to those in complete remission (CR). Rux significantly reduced B7-H3 expression in MMBMMCs in patients with PD, MM cells (U266), and BM from patients in PD when co-cultured with stromal cells (HS-5) after 48-72 hours. Rux decreased B7-H3 expression in the human MM xenograft model LAGλ-1A when cultured ex vivo. In addition, Rux suppressed B7-H3 at protein levels as shown with flow cytometric analysis and western blotting, consistent with the gene expression results. Next, we tested whether B7-H3 blockade by Rux could potentially restore exhausted T cell activity against myeloma cells in MMBM. We found that Rux can increase IL-2 and CD8 gene expression in MMBM with lower plasma percentages (< 30%) but not among those with higher plasma cell percentages (>70%). Rux also elevated IL-2 and CD8 gene expression in BM when it was cocultured with T cells (SUP-T1), suggesting Rux may mediate immunological cytokine signaling. B7-H3-neutralizing antibody increased CD8 gene expression in MMBM in vitro, suggesting that one of the mechanisms through which Rux upregulates CD8 T cells in MMBM may be via downregulation of B7-H3. Conclusion: The immune checkpoint protein B7-H3 is overexpressed in MMBM in PD compared to CR patients. The JAK1/2 inhibitor Rux can decrease B7-H3 expression and increase IL-2 and CD8 expression in BM in vitro. Our results provide evidence for Rux inhibiting the immune checkpoint protein B7-H3 which may potentially restore exhausted T-cell activity in the MMBM tumoral microenvironment. Disclosures Chen: Oncotraker Inc: Equity Ownership. Berenson:OncoTracker: Equity Ownership, Other: Officer; OncoTracker: Equity Ownership, Other: Officer; Bristol-Myers Squibb: Honoraria, Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; Incyte Corporation.: Consultancy, Research Funding; Incyte Corporation.: Consultancy, Research Funding; Takeda: Consultancy, Speakers Bureau; Takeda: Consultancy, Speakers Bureau; Janssen: Consultancy, Speakers Bureau; Janssen: Consultancy, Speakers Bureau; Amag: Consultancy, Speakers Bureau; Amag: Consultancy, Speakers Bureau; Amgen: Consultancy, Speakers Bureau; Amgen: Consultancy, Speakers Bureau; Sanofi: Consultancy; Sanofi: Consultancy.

Bone marrow morphologic features, MyPRS, and gene mutation correlations in plasma cell myeloma.

Genetics has played an important role in risk stratification for plasma cell myeloma patients, providing therapeutic guidance. In this study, we investigated the correlation of bone marrow morphologic features and genetic aberrations, including gene expression profiles, translocations, and gene mutations. For the first time we show that high plasma cell volume, diffuse sheet growth pattern, immature cell morphology, high mitotic index, and increased reticulin fibrosis, significantly correlates with high risk disease determined by MyPRS gene expression profiles. Furthermore, we show the association between MyPRS risk stratification and chromosomal alterations and specific gene mutations. We also demonstrate the combinational effect of TP53 mutation and 17p loss on the histological changes in bone marrow.

Role of Histopathology in the Diagnosis of Cutaneous Leishmaniasis: A Case-Control Study in Sri Lanka.

Cutaneous leishmaniasis (CL) displays a spectrum of manifestations clinically and histologically. Then, it becomes a diagnostic challenge and must discern from the other clinical and histological mimics, especially when the Leishman-Donovan bodies are inattentive. In this study, we compared the distinguishing histomorphological characteristics of CL against the other skin diseases with similar clinical and histological features. Skin biopsies of 181 patients, which suspect CL clinically, are evaluated histologically. Pertaining to the first case-control comparison, which performed between skin lesions of CL with or without discernible organisms and the other granulomatous dermatitis, highlighted that the ill-formed coalescent granulomata (OR = 14.83) and diffuse dense dermal plasma cell infiltrate (OR = 74.25) are significantly associated with the skin lesions of CL. The second case-control analysis was between CL without discernible organisms and the other granulomatous dermatitis, and identified a significant association in the presence of ill-formed coalescent granulomata (OR = 16.94) and diffuse dense (>50/HPF) dermal plasma cell infiltrate (OR = 74.5) in the skin lesions of CL. Pertaining to epidermal changes, acanthosis (OR = 2.38), spongiosis (OR = 9.13), and the presence of ulceration (OR = 20.26) are among the major concerns in CL. In conclusion, in the presence of clinical suspicion, dermal granulomata in ill-formed coalescent morphology with high plasma cell density in a diffuse arrangement are positive factors for the diagnosis of CL, especially when the discernible Leishmania amastigotes are absent. Resource utilization such as polymerase chain reaction and other ancillary techniques during the diagnosis of CL can be minimized by using a range of histopathological features and special attention should be focused on this in the future.

Impact of acquired del(17p) in multiple myeloma

AbstractThe high-risk abnormality del(17p) can be detected by fluorescence in situ hybridization on malignant plasma cells (PCs) and has an adverse prognostic impact in patients with multiple myeloma (MM). Patients with del(17p) have reduced overall survival (OS). Patients who acquire del(17p) later during the disease course are not well described. The disease characteristics at diagnosis predicting for acquired del(17p) and its overall impact on patient survival is not known. We compared 76 patients with MM who were negative for del(17p) at diagnosis and acquired it later with 152 control MM patients who did not acquire del(17p) at a comparable time point. Patients acquired del(17p) at a median of 35.6 months (range, 4.6-116.1 months) from diagnosis of MM after a median of 2 lines of therapy (range, 1-10 lines of therapy). When compared with controls, patients with acquired del(17p) had shorter median progression-free survival (PFS) (30.1 vs 23.0 months; P = .032) and OS (106.1 vs 68.2 months; P < .001) from diagnosis. After the detection of del(17p), the median PFS was 5.4 months and the median OS was 18.1 months. High lactate dehydrogenase level (odds ratio [OR], 3.69; 95% confidence interval [CI], 1.11-12.24) and presence of t(4;14) (OR, 2.66; 95% CI, 1.09-6.48) or any high-risk translocation (OR, 2.23; 95% CI, 1.00-4.95) at diagnosis predicted acquisition of del(17p). High PC proliferative rate predicted shorter OS from detection of del(17p) (hazard ratio, 2.28; 95% CI, 1.31-3.96; P = .004). Our study shows that acquisition of del(17p) is an important molecular event associated with reduction in OS in MM. Certain baseline factors may predict acquisition of del(17p). This needs validation in prospective data sets.

Systemic AL amyloidosis with high bone marrow plasma cells (BMPCs) infiltration: a case report and literature review

Light chain (AL) amyloidosis is a complex and often fatal disease caused by misfolded protein deposition characterized by monoclonal immunoglobulin light-chain fibrils in tissues and organs (1). This light chain protein, usually produced by a small and indolent plasma cell clone, is responsible for positive staining with Congo red when observed under polarized light, a gold standard for the diagnosis of AL amyloidosis (2).