Limitations of VS38c labeling in the detection of plasma cell myeloma by flow cytometry.

Plasma cell myeloma (multiple myeloma [MM]) is a malignant neoplasm originating from the plasma cells. Besides other methods, flow cytometric analysis of the patient's bone marrow aspirate has an important role in the diagnosis and also in the response assessment. Since the cell surface markers, used for identifying abnormal plasma cells, are expressed diversely and the treatment can also alter the phenotype of the plasma cells, there is an increasing demand for new plasma cell markers. VS38c is a monoclonal antibody that recognizes the CLIMP-63 protein in the membrane of the endoplasmic reticulum. CLIMP-63 is known to be expressed at high levels in normal and pathologic plasma cells in the bone marrow, thus VS38c antibody can be used to identify them. Although VS38c staining of plasma cells is reported to be constant and strong even in myeloma, we were wondering whether sample preparation can affect the staining. We have investigated the effect of different permeabilization agents and washing of the cells on the quality of the VS38c staining and found that in many cases the staining is inadequate to identify the plasma cells. We measured the VS38c staining of the bone marrow aspirates of 196 MM patients and observed that almost all cases showed bright staining with VS38c. However, permeabilization with mild detergent resulted in the appearance of a significant VS38cdim subpopulation, which showed increased sensitivity to mechanical stress (centrifugation). Our results indicate that VS38cdim MM cells can appear due to the improper permeabilization of the endoplasmic reticulum and this finding raises the possibility of the existence of a plasma cell subpopulation with different membrane properties. The significance of this population is unclear yet, but these cells can be easily missed with VS38c staining and can be lost due to centrifugation-induced lysis during sample preparation.

Dysregulation of the endothelial nitric oxide pathway is associated with airway inflammation in COPD.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is related to endothelial dysfunction and the impaired generation of nitric oxide (NO) from L-arginine by the endothelial NO synthase (eNOS). The relationship between eNOS dysfunctionality and airway inflammation is unknown. We assessed serum asymmetric and symmetric dimethylarginine (ADMA and SDMA) and nitrite/nitrate concentrations, indicators of eNOS function, in patients with COPD and correlated them with markers of inflammation. METHODS: We recruited 15 control smokers, 29 patients with stable and 32 patients with exacerbated COPD requiring hospitalization (20 of them were measured both at admission and discharge). Serum L-arginine, ADMA, SDMA, nitrite and nitrate were measured and correlated with airway inflammatory markers (fractional exhaled nitric oxide concentration - FENO, sputum nitrite and nitrate, sputum cellularity), serum C-reactive protein - CRP, white blood cell count, lung function and blood gases. ANOVA, t-tests and Pearson correlation were used (mean ± SD or geometric mean ± geometric SD for nitrite/nitrate). RESULTS: Serum L-arginine/ADMA, a marker of substrate availability for eNOS, was lower in stable (214 ± 58, p < 0.01) and exacerbated COPD (231 ± 68, p < 0.05) than in controls (287 ± 64). The serum concentration of SDMA, a competitor of L-arginine transport, was elevated during an exacerbation (0.78 ± 0.39 µM) compared to stable patients (0.53 ± 0.14 µM, p < 0.01) and controls (0.45 ± 0.14 µM, p < 0.001). ADMA correlated with blood neutrophil percentage (r = 0.36, p < 0.01), FENO (r = 0.42, p < 0.01) and a tendency for positive association was observed to sputum neutrophil count (r = 0.33, p = 0.07). SDMA correlated with total sputum inflammatory cell count (r = 0.61, p < 0.01) and sputum neutrophil count (r = 0.62, p < 0.01). Markers were not related to lung function, blood gases or CRP. L-arginine/ADMA was unchanged, but serum SDMA level decreased (0.57 ± 0.42 µM, p < 0.05) after systemic steroid treatment of the exacerbation. Serum nitrite level increased in stable and exacerbated disease (4.11 ± 2.12 and 4.03 ± 1.77 vs. control: 1.61 ± 1.84 µM, both p < 0.001). CONCLUSIONS: Our data suggest impaired eNOS function in stable COPD, which is transiently aggravated during an exacerbation and partly reversed by systemic steroid treatment. Serum ADMA and SDMA correlate with airway inflammatory markers implying a possible effect of anti-inflammatory therapy on endothelial dysfunction. Serum nitrite can serve as a compensatory pool for impaired endothelial NO generation.

Diurnal variation of circulating microvesicles is associated with the severity of obstructive sleep apnoea.

PURPOSE: Microvesicles (MVs) have been implicated in the pathomechanism of obstructive sleep apnoea (OSA); however, the results are inconsistent, possibly due to an unrevealed temporal variation in circulating MV levels. We aimed to investigate the diurnal changes of MV fractions in OSA. METHODS: Peripheral blood was taken from 18 patients with OSA and 9 healthy subjects at different time points (11:00, 17:00, 21:00, 01:30 and 06:00). Samplings were repeated in nine OSA patients after 2 months of continuous positive airway pressure (CPAP) therapy. CD41+, CD62P+, glycophorin A+ and Annexin V+ MVs were determined with flow cytometry. Areas under the MV concentrations-time curves (AUC) were calculated and correlated with the severity of OSA. RESULTS: A significant diurnal variability of plasma CD41+ and Annexin V+ MVs was observed only in OSA with a marked peak at 17:00. There was a direct correlation between CD41+ MV AUCs and the severity of OSA. CPAP treatment reduced diurnal variability in both CD41+ and Annexin V+ MV levels. CONCLUSIONS: The relationship between the diurnal variability of CD41+ MVs and disease severity as well as the effect of CPAP treatment on MV levels support the role of MVs in the pathophysiology of OSA. More importantly, considering the significant diurnal variation in circulating MV levels, introduction of strict protocols for blood sampling is required for MV measurements.

Peripheral blood and bronchoalveolar leukocyte profile in lung transplant recipients and their changes according to immunosuppressive regimen: A single-center experience.

BACKGROUND: After lung transplantation (LuTX), lower respiratory tract infections (LRTI) and acute cellular rejection (ACR) are associated with changes in peripheral blood and bronchoalveolar lavage fluid mononuclear cell profile (PBMC and BALIC). PBMC is also influenced by immunosuppressive regimen and its changes with postoperative time. First-year PBMC and BALIC changes were evaluated in this study with rabbit anti-thymocyte globulin (ATG) and alemtuzumab (AL) induction therapy. METHODS: In total, 64 LuTX recipients were included, 53 of them received AL and 11 ATG as induction therapy. PBMC and BALIC were examined routinely and in cases suspicious of infection and/or rejection. A PBMC- and BALIC-based algorithm for infection and rejection prediction was also tested. RESULTS: In the AL group, peripheral blood lymphocyte and basophil cell numbers were significantly reduced, while the neutrophil cell number elevation during LRTI was significantly higher compared to the control. Early postoperative measurements showed a lower BALIC lymphocyte count. The algorithm had 17% sensitivity and 94% specificity for ACR in all patients and 33% sensitivity and 95% specificity for ACR with coexisting LRTI. CONCLUSION: BALIC is not significantly influenced by the immunosuppressive regimen. PBMC- and BALIC-based algorithm may improve the differential diagnosis of ACR.

Galectin-9 in allergic airway inflammation and hyper-responsiveness in mice.

BACKGROUND: Galectin-9 (Gal-9) is a member of the growing family of beta-galactoside-binding lectins. Gal-9 is an eosinophil chemoattractant and inducer of Th1 cell apoptosis. These effects suggest its potential role in the pathogenesis of asthma. Our aim was to study the expression of Gal-9 in an ovalbumin (OVA)-induced mouse model of allergic asthma. METHODS: To investigate the significance of Gal-9 in allergic inflammation and airway hyperresponsiveness (AHR), a group of BALB/c mice was sensitized and challenged with OVA (G(OVA)). Another group of animals was allergized with OVA and also treated with dexamethasone (DEX) (G(OVA+DEX)). The control group (G(PBS)) received phosphate-buffered saline instead of OVA as placebo. Airway reactivity to intravenous methacholine was assessed. RESULTS: The percentage of Gal-9-positive cells and their intracellular Gal-9 content and Th1/Th2 cytokine levels in the bronchoalveolar lavage (BAL) were determined by flow cytometry. Gal-9 mRNA expression and protein level were measured in the lung tissue by real-time RT-PCR and Western blot. In G(OVA )mice, airway inflammation and mucus hypersecretion developed. DEX treatment inhibited the main features of experimental asthma. The number of Gal-9-positive lymphocytes, eosinophil and neutrophil granulocytes and the levels of Th2 cytokines were higher in the BAL of G(OVA) compared to G(PBS) or G(OVA+DEX )mice. Moreover, Gal-9 protein level was elevated in the lungs of G(OVA) mice. CONCLUSIONS: These results suggest that Gal-9 plays a role as a mediator contributing to the development of allergic airway inflammation. Gal-9 may serve as a recruiter of eosinophil granulocytes and promoter of Th2 dominance.

Increased synthesis of vascular endothelial growth factor in allergic airway inflammation in histidine decarboxylase knockout (HDC(-/-)) mice.

Histamine and vascular endothelial growth factor (VEGF) have been implicated in the pathogenesis of allergic asthma; they enhance inflammation, vascular permeability, and mucus secretion. Histamine was suggested to alter the level of VEGF via the H2 receptors. Here the authors have applied histidine decarboxylase gene-targeted (HDC(-/-)) mice, lacking histamine, to investigate the effect of histamine deficiency on VEGF expression in an animal model of asthma. HDC(-/-) and wild-type (WT) mice were sensitized and challenged with ovalbumin (OVA). VEGF mRNA expression and protein level were determined in the lung. Number of VEGF-positive immune cells of bronchoalveolar lavage (BAL) and their intracellular VEGF content were measured by flow cytometry. VEGF protein level in the lung and in the BAL cells was increased in OVA treated (HDC(-/-)(ova) as well as in WT(ova)) animals compared to their controls. However, there was no difference in the VEGF levels between HDC(-/-) or WT animals, either in the lung or in the BAL cells. In conclusion, increased VEGF production of the lung or BAL immune cells can be induced by allergen provocation independently from the genetic background of the animals. These data suggest that VEGF-mediated allergic processes can persist in the absence of histamine.

True insulin allergy? Lessons from a case of suspected insulin allergy / Inzulin-túlérzékenységi reakció vagy valami más? Tanulságok egy eset kapcsán.

Today, insulin hypersensitivity reactions are rare side effects of insulin therapy. In two-thirds of the suspected insulin allergy cases, the clinical symptoms are not related to insulin. The authors report the case of a 64-year-old female patient, by whom lymphocyte tarnsformation test (LTT) has been used to elucidate the background of allergic symptoms developed during insulin therapy. The performed LTT did not support hypersensitivity to insulin, however, the positive protamine test raised the suspicion of fish allergy. Complementary immunoserology also highlighted the coexistence of previously unrevealed thyroid disease. To our knowledge, this is the first documented case report in Hungary that attempts to address the real cause of a suspected hypersensitivity reaction to insulin by using LTT. Orv Hetil. 2020; 161(35): 1483-1487.

Effect of COPD on Inflammation, Lymphoid Functions and Progression-Free Survival during First-Line Chemotherapy in Advanced Non-small Cell Lung Cancer.

Chronic obstructive pulmonary disease (COPD) is a common comorbidity of non-small cell lung cancer (NSCLC). COPD is characterized by systemic inflammation and lymphocyte dysfunction, mechanisms that are also known to accelerate progression of advanced (IIIB-IV) stage NSCLC. We aimed to find out whether COPD exerts an influence on tumor induced inflammatory and lymphoid responses and progression-free survival (PFS) after first-line treatment in advanced NSCLC. Patients suffering from NSCLC (n = 95), COPD (n = 54), NSCLC+COPD (n = 80) and healthy controls (n = 60) were included. PFS, neutrophil granulocyte and lymphocyte cell counts were recorded. Serum IFNγ, TNFα, VEGF concentrations were measured by using multiplex cytometric bead-based immunoassay. Prevalence of myeloid-derived suppressor cell populations (MDSC-s), and signs of T cell exhaustion were tested by using flow cytometry. Median PFS increased in the NSCLC+COPD group compared to NSCLC patients without COPD (7.4 vs 4.9 months, p < 0.01). NSCLC+COPD patients had 1.7 times (1.2-2.4) more likely to have longer PFS compared to NSCLC patients without COPD (Cox analysis, p < 0.01). Neutrophil cell counts, CRP, IFNγ and TNFα concentrations were all reduced in NSCLC+COPD (all p < 0.05 vs NSCLC). NSCLC+COPD was also associated with reduced serum IL-10 concentration and increased granzyme-B positive CD8 cell counts compared to NSCLC without COPD. The effects of VEGF and MDSC-s on systemic inflammation appeared to be blunted by COPD in patients suffering from advanced NSCLC. Concomitant COPD moderates tumor-induced inflammation and supports some effector lymphoid functions and thereby may be an independent positive predictive factor of longer PFS after first-line therapy in advanced NSCLC.

Mechanisms of Subcutaneous and Sublingual Aeroallergen Immunotherapy: What Is New?

Allergen immunotherapy (AIT) is considered to be the only treatment option with the promise of healing and induction of long-lasting allergen tolerance, persisting even after discontinuation of therapy. Despite a more than 100-year-long history, still only a minority of patients are being treated with AIT. Substantial developments took place in the last decade to overcome problems in standardization, efficacy, safety, high costs, long duration of treatment; and new guidelines have also been implemented. Major advancements in the understanding of AIT mechanisms with the focus on recent findings of subcutaneous and sublingual AIT have been summarized.

Highlights of Novel Vaccination Strategies in Allergen Immunotherapy.

Increasing safety while maintaining or even augmenting efficiency are the main goals of research for novel vaccine development and improvement of treatment schemes in allergen immunotherapy (AIT). To increase the efficacy of AIT, allergens have been coupled to innate immunostimulatory substances and new adjuvants have been introduced. Allergens have been modified to increase their uptake and presentation. Hypoallergenic molecules have been developed to improve the safety profile of the vaccines. Administration of recombinant IgG4 antibodies is a new, quick, passive immunization strategy with remarkable efficiency. Results of some current investigations aiming at further improvement of AIT vaccines have been summarized.