Comparison of humoral and cellular immune responses in hematologic diseases following completed vaccination protocol with BBIBP-CorV, or AZD1222, or BNT162b2 vaccines against SARS-CoV-2.

Background: Vaccination has proven the potential to control the COVID-19 pandemic worldwide. Although recent evidence suggests a poor humoral response against SARS-CoV-2 in vaccinated hematological disease (HD) patients, data on vaccination in these patients is limited with the comparison of mRNA-based, vector-based or inactivated virus-based vaccines. Methods: Forty-nine HD patients and 46 healthy controls (HCs) were enrolled who received two-doses complete vaccination with BNT162b2, or AZD1222, or BBIBP-CorV, respectively. The antibodies reactive to the receptor binding domain of spike protein of SARS-CoV-2 were assayed by Siemens ADVIA Centaur assay. The reactive cellular immunity was assayed by flow cytometry. The PBMCs were reactivated with SARS-CoV-2 antigens and the production of activation-induced markers (TNF-α, IFN-γ, CD40L) was measured in CD4+ or CD8+ T-cells ex vivo. Results: The anti-RBD IgG level was the highest upon BNT162b2 vaccination in HDs (1264 BAU/mL) vs. HCs (1325 BAU/mL) among the studied groups. The BBIBP-CorV vaccination in HDs (339.8 BAU/mL ***p < 0.001) and AZD1222 in HDs (669.9 BAU/mL *p < 0.05) resulted in weaker antibody response vs. BNT162b2 in HCs. The response rate of IgG production of HC vs. HD patients above the diagnostic cut-off value was 100% vs. 72% for the mRNA-based BNT162b2 vaccine; 93% vs. 56% for the vector-based AZD1222, or 69% vs. 33% for the inactivated vaccine BBIBP-CorV, respectively. Cases that underwent the anti-CD20 therapy resulted in significantly weaker (**p < 0.01) anti-RBD IgG level (302 BAU/mL) than without CD20 blocking in the HD group (928 BAU/mL). The response rates of CD4+ TNF-α+, CD4+ IFN-γ+, or CD4+ CD40L+ cases were lower in HDs vs. HCs in all vaccine groups. However, the BBIBP-CorV vaccine resulted the highest CD4+ TNF-α and CD4+ IFN-γ+ T-cell mediated immunity in the HD group. Conclusion: We have demonstrated a significant weaker overall response to vaccines in the immunologically impaired HD population vs. HCs regardless of vaccine type. Although, the humoral immune activity against SARS-CoV-2 can be highly evoked by mRNA-based BNT162b2 vaccination compared to vector-based AZD1222 vaccine, or inactivated virus vaccine BBIBP-CorV, whereas the CD4+ T-cell mediated cellular activity was highest in HDs vaccinated with BBIBP-CorV.

Beneficial Effect of Lenalidomide-Dexamethason Treatment in Relapsed/Refractory Multiple Myeloma Patients: Results of Real-Life Data From 11 Hungarian Centers.

In Hungary, the cost of lenalidomide-based therapy is covered only for relapsed multiple myeloma (MM) patients, therefore lenalidomide is typically used in the second-line either as part of a triplet with proteasome inhibitors or as a doublet. Lenalidomide-dexamethasone is a standard treatment approach for relapsed/refractory MM, and according to recent large randomized clinical trials (RCT, the standard arm of POLLUX, ASPIRE, TOURMALINE), the progression-free survival (PFS) is expected to be approximately 18 months. We surveyed ten Hungarian centers treating MM and collected data of 278 patients treated predominantly after 2016. The median age was 65 years, and patients were distributed roughly equally over the 3 international staging system groups, but patients with high risk cytogenetics were underrepresented. 15.8% of the patients reached complete response, 21.6% very good partial response, 40.6% partial response, 10.8% stable disease, and 2.5% progressed on treatment. The median PFS was unexpectedly long, 24 months, however only 9 months in those with high risk cytogenetics. We found interesting differences between centers regarding corticosteroid type (prednisolone, methylprednisolone or dexamethasone) and dosing, and also regarding the choice of anticoagulation, but the outcome of the various centers were not different. Although the higher equivalent steroid dose resulted in more complete responses, the median PFS of those having lower corticosteroid dose and methylprednisolone were not inferior compared to the ones with higher dose dexamethasone. On multivariate analysis high risk cytogenetics and the number of prior lines remained significant independent prognostic factors regarding PFS (p < 0.001 and p = 0.005). Our results show that in well-selected patients Lenalidomide-dexamethasone can be a very effective treatment with real-world results that may even outperform those reported in the recent RCTs. This real world information may be more valuable than outdated RCT data when treatment options are discussed with patients.

[Left ventricular deformation in cardiac light-chain amyloidosis and hypereosinophilic syndrome. Results from the MAGYAR-Path Study]. / Bal kamrai deformáció cardialis könnyulánc-amyloidosisban és hypereosinophilia-szindrómában. Eredmények a MAGYAR-Path Tanulmányból.

Introduction: Hypereosinophilic syndrome (HES) and immunoglobulin light-chain amyloidosis (ALA) are two, rare haematological disorders associated with cardiac alterations. Aim: The goal of the present study was a comparative assessment of left ventricular (LV) deformational parameters in HES and ALA patients using three-dimensional speckle-tracking echocardiography (3DSTE). Method: In the present study, results of 10 HES patients (mean age: 60.9 ± 14.7 years) and 19 ALA patients (mean age: 63.4 ± 7.8 years, 13 males) were analysed. The control group contained 13 age- and gender-matched healthy adults (mean age: 59.2 ± 4.3 years, 5 males). All patients underwent a complete two-dimensional Doppler echocardiography followed by 3DSTE. Results: All basal segmental LV strains were significantly reduced in ALA patients as compared to the control group. Global and mean segmental LV longitudinal strain (LS) values of ALA patients proved to be significantly decreased as compared to those of the healthy control group. During comparison of HES patients and healthy controls, significant difference could be detected in global LV-LS, while segmental basal LV-LS was also significantly reduced in HES patients. Basal LV radial and 3D strains showed significant differences when parameters of HES and ALA patient groups were compared. Conclusion: 3DSTE is a feasible tool for the detailed assessment of LV deformation in HES and ALA patients. Significant LV deformational abnormalities could be detected in both groups. In the case of ALA, these abnormalities are more prominent. Orv Hetil. 2020; 161(5): 169-176.

Left ventricular rotational mechanics in hypereosinophilic syndrome-Analysis from the three-dimensional speckle-tracking echocardiographic MAGYAR-Path Study.

INTRODUCTION: Hypereosinophilic syndrome (HES) is a very heterogeneous group of disorders with varied etiologies characterized by peripheral eosinophilia and eosinophilic tissue/end-organ damage. Three-dimensional speckle-tracking echocardiography (3DSTE) was used for assessment of left ventricular (LV) rotational mechanics in HES patients. METHODS: The study comprised 13 HES patients, from which one patient was excluded due to insufficient image quality. The remaining patient population consisted of 12 HES cases (mean age: 59.7 ± 13.7 years, eight males). The control group consisted of 36 healthy volunteers (mean age: 52.9 ± 8.3 years, 23 males). 3DSTE was used for the evaluation of LV rotational abnormalities. RESULTS: Both LV apical rotation (4.86 ± 1.92 degree vs 10.07 ± 3.92 degree, P < .0001) and LV twist (8.52 ± 2.79 degree vs 14.41 ± 4.26 degree, P < .0001) showed significant deteriorations in most of HES patients. Time-to-peak LV apical rotation (380 ± 115 ms vs 344 ± 69 ms, P = .56), LV basal rotation (335 ± 148 ms vs 337 ± 111 ms, P = .89), and LV twist (348 ± 91 ms vs 320 ± 60 ms, P = .64) were not significantly different between HES patients and controls. No correlations could be detected between absolute eosinophil count and eosinophil ratio and apical LV rotation (r = 0.12, P = .51 and r = 0.23, P = .45, respectively) and LV twist (r = 0.24, P = .39 and r = 0.31, P = .34, respectively). In two subjects, the absence of LV twist called LV "rigid body rotation" (RBR) was detected. CONCLUSIONS: Reduced LV apical rotation and twist could be demonstrated in HES. LV-RBR could be detected in some HES patients.

Aortic stiffness is increased in patients with hypereosinophilic syndrome being in early necrotic phase.

BACKGROUND: Persistent eosinophilia and eosinophil-mediated single- or multiple-organ damage are typical features of hypereosinophilic syndrome (HES). Theoretically, eosinophilic infiltration of the ascending aortic wall could not be excluded in HES, therefore the present study aimed to test whether HES is associated with abnormalities in aortic elastic properties. METHODS: The present study comprised 10 HES patients (mean age: 57.6±10.1 years, 5 males) without known cardiovascular disease, their results were compared to 19 age-, gender- and risk factor-matched controls (59.2±4.2 years, 15 males). Complete two-dimensional Doppler echocardiography with measurement of echocardiographic aortic elastic properties was performed in all HES cases and controls. RESULTS: Although neither systolic (30.6±3.4 vs. 30.1±3.6 mm, P=ns), nor diastolic (28.7±3.6 vs. 27.8±3.2 mm, P=ns) aortic diameter differed significantly between HES patients and matched controls, significantly increased aortic stiffness index (11.19±5.65 vs. 7.04±2.97, P<0.05) could be demonstrated in HES patients. CONCLUSIONS: Increased aortic stiffness could be demonstrated in HES patients in their early necrotic phase.

Characterization of left atrial dysfunction in hypereosinophilic syndrome - Insights from the Motion analysis of the heart and great vessels by three-dimensional speckle tracking echocardiography in pathological cases (MAGYAR-Path) Study.

INTRODUCTION: The present study was designed to compare three-dimensional speckle tracking echocardiography (3DSTE)-derived left atrial (LA) volumetric, volume-based functional and strain parameters between patients with hypereosinophilic syndrome (HES) and matched controls. METHODS: A total of 10 HES patients and 19 age- and gender-matched healthy controls were included in the study. Complete two-dimensional Doppler echocardiography and 3DSTE were performed in all HES cases and controls. RESULTS: Significantly increased maximum (72.9±38.8 ml vs. 45.6±15.5 ml, p=0.01) and minimum (46.3±33.3 ml vs. 26.0±15.0 ml, p=0.03) LA volumes and LA volume before atrial contraction (62.0±36.0 ml vs. 36.5±16.6 ml, p=0.01) were found in HES patients compared to controls. Both peak global (18.3±6.7% vs. 25.6±9.0%, p=0.03) and mean segmental (22.2±6.0% vs. 31.0±12.1%, p=0.04) circumferential strains were significantly reduced in HES patients, suggesting decreased LA reservoir function. CONCLUSION: Increased LA volumes can be demonstrated in HES patients, accompanied by reduced LA peak circumferential strain as assessed by 3DSTE, suggesting LA remodeling.

[Amyloidosis induced colonic stricture. The first symptom of myeloma multiplex. A case report]. / Amyloidosis okozta colonstrictura mint a myeloma multiplex elso tünete--Esetismertetés.

UNLABELLED: Systemic amyloidosis often involves the gastrointestinal tract and usually presents as ulceration or polypoid lesions. However, annular stricture of the colon due to amyloidosis is very rare. Amyloidosis develops in appr. 10% of multiple myeloma patients with lambda light chain production, it is usually type AL and not a presenting symptom. CASE REPORT: A 73-year-old female patient appeared at our hospital with anaemia, abdominal pain and hematochezia. Colonoscopy revealed a circular narrowing of the sigmoid colon suggesting malignancy. The patient underwent sigmoid resection and rectosigmoidal anastomosis was prepared to relieve mechanical obstruction. Surprisingly the histological finding from the resected specimen was amyloidosis. Subcutaneous fat tissue biopsy established the diagnosis of systemic AA amyloidosis. Immunoelectrophoresis revealed an elevated gamma-globulin fraction with IgG lambda monoclonal component, as well as a different lambda light chain. Therefore bone marrow biopsy was carried out which confirmed the diagnosis of multiple myeloma. DISCUSSION: Our case is a rare example of the extraordinary tumor-mimicking colon amyloidosis that led to the diagnosis of multiple myeloma. Beside haematological treatment, strict follow-up of the colon process and reconsideration of surgical therapy or endoscopic stenting is of great importance.

Cytosolic region of TM6 in P-glycoprotein: topographical analysis and functional perturbation by site directed labeling.

Reduced intracellular drug accumulation due to the activity of the drug efflux pump ABC (B1) is a major mechanism in the resistance of cancer cells to chemotherapy. ABC (B1) is a poly specific transporter, and the molecular mechanism of its complex translocation process remains to be elucidated. To understand the process will require information on the regions involved in drug binding and those that couple this event to nucleotide hydrolysis. The present investigation focuses on the cytosolic region of transmembrane helix 6 (TM6), which has been widely attributed with a central role in the translocation process. A series of ABC (B1) isoforms containing a unique cysteine within TM6 was constructed and the resultant proteins purified and reconstituted. Accessibility of the cysteines to covalent modification by maleimide reagents was measured for the basal, ATP bound and vanadate trapped conformations of each isoform. Residues at the two extremes of the TM6 region examined (amino acids 344 to 360) were considerably more accessible than the central segment, the latter of which also failed to undergo significant conformational changes during the catalytic cycle. Covalent modification of the cytosolic segment of TM6 did, however, attenuate drug stimulation of ATP hydrolysis and demonstrates an important role for this segment in coupling drug binding to ATP hydrolysis during translocation.

Purification and 3D structural analysis of oligomeric human multidrug transporter ABCG2.

ABCG2 is a multidrug efflux pump associated with resistance of cancer cells to a plethora of unrelated drugs. ABCG2 is a "half-transporter," and previous studies have indicated that it forms homodimers and higher oligomeric species. In this manuscript, electron microscopic structural analysis directly addressed this issue. An N-terminal hexahistidine-tagged ABCG2(R482G) isoform was expressed to high levels in insect cells. An extensive detergent screen was employed to effect extraction of ABCG2(R482G) from membranes and identified only the fos-choline detergents as efficient. Soluble protein was purified to >95% homogeneity by a three-step procedure while retaining the ability to bind substrates. Cryonegative stain electron microscopy of purified ABCG2(R482G) provided 3D structural data at a resolution of approximately 18 A. Single-particle analysis revealed that the complex forms a tetrameric complex ( approximately 180 A in diameter x approximately 140 A high) with an aqueous central region. We interpret the tetrameric structure as comprising four homodimeric ABCG2(R482G) complexes.

Diffusivity and distribution of vinblastine in three-dimensional tumour tissue: experimental and mathematical modelling.

The distribution of chemotherapeutics in solid tumours is poorly understood and the contribution it makes to treatment failure is unknown. Novel approaches are required to understand how the three-dimensional organisation of cancer cells in solid tumours affects drug availability. Since convective drug transport is limited by increased interstitial pressure in poorly vascularised cancers, the aim of this study was to measure the diffusive hindrance exerted by solid tumour tissue. Multicell layer tumour models comprising DLD1 colon cancer cells were characterised and fluxes were determined for [3H]-vinblastine and [14C]-sucrose. The mathematical models provided the diffusion coefficients for both compounds and predicted higher exposure of cells in the vicinity of vessels. The diffusion of vinblastine was three times slower than that of sucrose. Although slow diffusion delays vinblastine penetration into the avascular regions of tumours, the proliferating cells are generally in the marginal area of tumours. The mathematical model that we have developed enabled accurate quantification of drug pharmacokinetic behaviour, in particular, the diffusivity of vinblastine within solid tissue. This mathematical model may be adapted readily to incorporate the influence of factors mediating pharmacokinetic drug resistance.

Modulation of multidrug resistance efflux pump activity to overcome chemoresistance in cancer.

Early publications using cultured cancer cells immediately recognized the phenomenon of resistance to anticancer agents. However, it was not until 1973 that it was first demonstrated that a major factor in the resistance of cancer cells was that of reduced drug accumulation. This year marks the 30th anniversary of the discovery by Juliano and Ling that P-glycoprotein mediates this active efflux of chemotherapeutic drugs from cancer cells. Since this seminal finding, the investigation of P-glycoprotein (MDR1, ATP binding cassette [ABC]B1) has proceeded with great vigour. However, it soon became apparent that P-glycoprotein was not expressed in all drug-resistant cells that displayed an accumulation deficiency, which led to the discovery of other ABC transporters involved in drug efflux. In 1992, the multidrug resistance-associated protein (MRP1, ABCC1) was identified in small cell lung cancer followed by breast cancer resistance protein (mitoxantrone resistance protein, ABCG2) in 1999. After three decades of research, can we confidently define the contribution of multidrug resistance transporters to chemoresistance and do we have clinically useful drugs to sensitise cancers?

Can P-glycoprotein influence the bioavailability of iminosugar-based glucosylceramide synthase inhibitors?

Recently developed glucosylceramide synthase inhibitors with enhanced hydrophobicity display increased bioavailability in the central nervous system (CNS). Have these improvements come at a potential risk given that the improved glucosylceramide synthase inhibitors bear the hallmarks of P-glycoprotein substrates? This question warrants attention given the potential to induce adverse drug interactions or toxicity, if glucosylceramide synthase inhibitors are administered with other P-glycoprotein substrates. The aim of this study was to determine if glucosylceramide synthase inhibitors are substrates for the multidrug transporter P-glycoprotein. Direct measurements of glucosylceramide synthase inhibitors binding to P-glycoprotein were examined, as was their ability to modulate transport by the protein. The more hydrophobic glucosylceramide synthase inhibitors caused a reduction in drug binding to P-glycoprotein. However, the compounds did not achieve this by direct interaction with the protein, but through a general membrane perturbation. Furthermore, the alterations in drug-P-glycoprotein interaction did not manifest as altered cellular accumulation of glucosylceramide synthase inhibitors or altered efficacy to reduce cellular glycolipid levels. Consequently, P-glycoprotein expression will not contribute significantly to the pharmacokinetic profile of the iminosugar glucosylceramide synthase inhibitors.

Three-dimensional structure of P-glycoprotein: the transmembrane regions adopt an asymmetric configuration in the nucleotide-bound state.

Multidrug resistance of cancer cells and pathogens is a serious clinical problem. A major factor contributing to drug resistance in cancer is the over-expression of P-glycoprotein, a plasma membrane ATP-binding cassette (ABC) drug efflux pump. Three-dimensional structural data with a resolution limit of approximately 8 A have been obtained from two-dimensional crystals of P-glycoprotein trapped in the nucleotide-bound state. Each of the two transmembrane domains of P-glycoprotein consists of six long alpha-helical segments. Five of the alpha-helices from each transmembrane domain are related by a pseudo-2-fold symmetry, whereas the sixth breaks the symmetry. The two alpha-helices positioned closest to the (pseudo-) symmetry axis at the center of the molecule appear to be kinked. A large loop of density at the extracellular surface of the transporter is likely to correspond to the glycosylated first extracellular loop, whereas two globular densities at the cytoplasmic side correspond to the hydrophilic, nucleotide-binding domains. This is the first three-dimensional structure for an intact eukaryotic ABC transporter. Comparison with the structures of two prokaryotic ABC transporters suggests significant differences in the packing of the transmembrane alpha-helices within this protein family.

P-glycoprotein retains function when reconstituted into a sphingolipid- and cholesterol-rich environment.

P-glycoprotein (P-gp) appears to be associated within specialized raftlike membrane microdomains. The activity of P-gp is sensitive to its lipid environment, and a functional association in raft microdomains will require that P-gp retains activity in the microenvironment. Purified hamster P-gp was reconstituted in liposomes comprising sphingomyelin and cholesterol, both highly enriched in membrane microdomains and known to impart a liquid-ordered phase to bilayers. The activity of P-gp was compared with that of proteoliposomes composed of crude egg phosphatidylcholine (unsaturated) or dipalmitoyl phosphatidylcholine (saturated) in the presence or absence of cholesterol. The maximal rate of ATP hydrolysis was not significantly altered by the nature of the lipid species. However, the potencies of nicardipine and XR9576 to modulate the ATPase activity of P-gp were increased in the sphingolipid-based proteoliposomes. The drug-P-gp interaction was investigated by measurement of the rates of [(3)H]XR9576 association and dissociation from the transporter. The lipid environment of P-gp did not affect these kinetic parameters of drug binding. In summary, P-gp retains function in liquid-ordered cholesterol and sphingolipid model membranes in which the communication between the transmembrane and the nucleotide binding domains after drug binding to the protein is more efficient.