Assessing alfalfa (Medicago sativa L.) tolerance to salinity at seedling stage and screening of the salinity tolerance traits

Salt is among the most harmful agents that negatively influences crop yield. Alfalfa is an important perennial forage crop that exhibits wide cultivar variations in salt tolerance. Developing salt-tolerant alfalfa plants is a promising way to utilize salinized land. A comprehensive method was developed to achieve reliable and effective evaluation of alfalfa salt resistance. This included principal components, membership functions and cluster and stepwise regression analyses. These were used to analyse the salt tolerance coefficients of 14 traits and to evaluate 20 diverse alfalfa cultivars at the seedling stage. The various morphological root parameters of six alfalfa cultivars with contrasting salt tolerance were also tested by a scanning apparatus. According to the comprehensive evaluation value (D value), one highly salt-tolerant, two salt-tolerant, four moderately salt-tolerant and 13 salt-sensitive alfalfa cultivars were screened. A mathematical equation for the evaluation of alfalfa salt tolerance was established: D' = -0.126 + 0.667SFW + 0.377SDW + 1.089K⁺ /Na⁺  + 0.172SFW/RFW (R²  = 0.988; average forecast accuracy of 96.95%), where four indices were closely related to the salt tolerance: shoot fresh weight, ratio of shoot fresh weight to root fresh weight, shoot dry weight and ratio of K⁺ to Na⁺ in the shoot. We also found that SSA correlated strongly with SFW, SDW, K⁺ /Na⁺ , D values, while SRV correlated obviously with SFW, SFW/RFW and D values after 150 mm NaCl treatment. In conclusion, the SFW, K⁺ /Na⁺ , SDW, SFW/RFW, SSA and SRV could be used as indicators of salt tolerance in alfalfa seedlings grown under 150 mm NaCl treatment.

[Four cases of acute diquat poisoning with prominent epileptoid seizure and literature review]

Objective: To further improve the awareness of the clinical feature of acute diquat poisoning. Methods: A retrospective analysis was performed on 4 cases of acute diquat poisoning with epileptoid seizure as the main clinical manifestation, which were admitted and diagnosed by the Characteristic Medical Center of Chinese People's Armed Police Force from January 1, 2017 to December 31, 2019. Take "Diquat" or "Deiquat" or "Reward" as keyword search for CNKI, Pubmed, and EMbase in both Chinese and English. The date of literature retrieval was from the database founding to December 31, 2019. Results: Of the 4 patients, 3 were male and 1 female, with an average age of 28 years (22-33 years) . The estimated dose was 8-20 g. All patients were treated with gastric lavage, catharsis, fluid replacement, blood perfusion, and in the early stage of treatment of epileptic seizures, the initial routine antiepileptic drugs had poor effect. Then propofol and midazolam were injected into the treatment. The epilepsy was relieved, but the condition deteriorated rapidly, and the patients died eventually. The literature search retrieved 3 patients in the 3 literatures included in the study were analyzed, and their clinical course was similar to that of 4 cases in the center. Necropsy was performedon all 3 patients, and the results were cerebral edema, diffuse cerebral edema, and hemorrhage around the basal ganglia. Conclusion: Acute diquat poisoning can cause epileptic seizures. Once it occurs, the disease progresses rapidly and the prognosis is poor. The combination of large dose of sedative drugs can be used to treat epilepsy in order to improve the prognosis.

AB0197 EFFICACY AND SAFETY OF HLX01 COMBINED WITH METHOTREXATE IN CHINESE PATIENTS WITH MODERATELY TO SEVERELY ACTIVE RHEUMATOID ARTHRITIS WHO HAD INADEQUATE RESPONSES TO METHOTREXATE: RESULTS OF A RANDOMISED, DOUBLE-BLIND, PLACEBO-CONTROLLED PHASE 3 STUDY

Background:

Rituximab is an effective therapy for rheumatoid arthritis (RA) patients with inadequate responses to methotrexate (MTX)1, 2. However, it has not been registered or approved in China for the treatment of RA by far. HLX01, an approved rituximab biosimilar (demonstrated in Chinese patients with diffuse large B-cell lymphoma)3, is thus evaluated in this study for the benefits of Chinese RA patients.

Objectives:

This study aimed to evaluate the efficacy and safety of HLX01 plus MTX versus placebo plus MTX in Chinese patients with active RA who had inadequate responses to MTX.

Methods:

This was a randomised, double-blind, placebo-controlled phase 3 study conducted in China (NCT03522415). Eligible patients were randomised 2:1 to receive intravenous infusion of 2×1000 mg HLX01 or placebo on day 1 and day 15. Patients with inadequate responses at week 16 and 20 were allowed to receive rescue treatments. Patients were retreated with or switched to receive (if initially assigned to placebo) 2×1000 mg rituximab at the first day of week 24 and 26. The primary endpoint of this study was the American College of Rheumatology criteria (ACR) 20 response at week 24. Secondary efficacy endpoints were evaluated at week 12, 24, 36 and 48. The safety, pharmacokinetics, pharmacodynamics and immunogenicity of HLX01 were observed and analyzed throughout the study.

Results:

Between May 28, 2018 and Sep 11, 2020, a total of 275 patients (ITT set) were randomised and 263 patients without major protocol deviations were included in per-protocol set (PPS). At week 24, HLX01 showed statistically superior efficacy (p <0.001) to placebo (ACR20: 60.7% vs 35.9% in ITT set, 60.3% vs 37.1% in PPS). Secondary efficacy endpoints were also significantly improved in HLX01 group compared with placebo (Table 1). The overall incidence of serious treatment emergent adverse events (TEAEs), adverse drug reactions (ADRs), and TEAEs leading to drug discontinuation were similar among treatment groups, with the most common TEAE been upper respiratory tract infection before (18.1% vs 18.5%) or after (13.0% vs 12.3%) week 24. Serum concentrations, immunogenicity and pharmacodynamics were similar between HLX01 and placebo groups.

Table 1.

Results of secondary efficacy endpoints at week 12, 24, 36 and 48 in ITT set.

DurationSecondary efficacy endpointsACR20 (%)ACR50 (%)ACR70 (%)DAS28-CRP(mean)HAQ-DI(mean)HLX01PlaceboHLX01PlaceboHLX01PlaceboHLX01PlaceboHLX01PlaceboBaseline5.495.431.401.45Week 1248.132.621.910.94.45.43.894.471.021.22Week 2460.735.936.618.515.312.03.394.370.871.22Week 3660.148.946.431.532.217.42.883.510.710.97Week 4873.862.055.240.239.927.22.823.510.721.03

Conclusion:

Comparing with placebo plus MTX, HLX01 plus MTX showed significantly improved clinical outcomes and comparable safety profiles in Chinese patients with moderately to severely active RA who had inadequate responses to MTX, demonstrating HLX01 in combination with MTX as a well-tolerated, safe and efficient treatment option.

References:

[1]Emery P, Deodhar A, Rigby WF, et al. Efficacy and safety of different doses and retreatment of rituximab: a randomised, placebo-controlled trial in patients who are biological naive with active rheumatoid arthritis and an inadequate response to methotrexate (Study Evaluating Rituximab’s Efficacy in MTX iNadequate rEsponders (SERENE)). Ann Rheum Dis. Sep 2010;69(9):1629-35. doi:10.1136/ard.2009.119933.

[2]Rubbert-Roth A, Tak PP, Zerbini C, et al. Efficacy and safety of various repeat treatment dosing regimens of rituximab in patients with active rheumatoid arthritis: results of a Phase III randomized study (MIRROR). Rheumatology (Oxford). Sep 2010;49(9):1683-93. doi:10.1093/rheumatology/keq116.

[3]Shi Y, Song Y, Qin Y, et al. A phase 3 study of rituximab biosimilar HLX01 in patients with diffuse large B-cell lymphoma. J Hematol Oncol. Apr 16 2020;13(1):38. doi:10.1186/s13045-020-00871-9.

Acknowledgements:

The authors would like to thank participants in this study and their families. They would also like to acknowledge other investigators and staff at all clinical sites and the members of the Independent Data Monitoring Committee.

Disclosure of Interests:

None declared

AB0762 THE CHARACTERISTICS OF PERIPHERAL LYMPHOCYTE SUBSETS IN PATIENTS WITH IGG4-RELATED DISEASE

Background:

Immunoglobulin G4-related disease (IgG4-RD) is an autoimmune disease with chronic systemic inflammation and fibrosis. The main feature of the disease was diffuse swell of the affected organs, and the serum IgG4 level was increased. Histopathology of the lesions showed infiltration of IgG4+ plasma cells. However, the pathogenesis of IgG4-RD is still unclear[1].

Objectives:

To explore the clinical characteristic of lymphocyte subsets of IgG4-related disease patients, and make comparisons with healthy controls.

Methods:

A total of 31 patients with IgG4-RD who were admitted to the Rheumatic Immunology Department of the Second Hospital of Shanxi Medical University from January 2016 to June 2020 were included. We collected their Clinical and laboratory data, and selected 30 age and sex matched healthy people as the control group. Flow cytometry was used to detect the percentage and absolute number of lymphocyte subsets (T, B, NK, CD4+T, CD8+T) and CD4+T subsets (Th1, Th2, Th17, CD4+CD25+Foxp3+Treg) in peripheral blood of IgG4-RD patients and healthy controls.

Results:

(1)The percentage of CD4+T cells in peripheral blood of IgG4-RD patients was higher than that of healthy controls [45.00(33.97-51.48) vs. 39.36(33.78-43.30), P<0.05]. (2)The percentage and absolute number of Th17 cells was increased in IgG4-RD patients [1.13(0.70-1.55) vs. 0.77(0.43-1.07), P<0.05; 7.90(5.20-12.23) vs. 5.60(3.12-8.47), P<0.05], while the percentage of Treg cells was decreased [3.37(2.82-5.65) vs. 4.96(4.18-6.34), P<0.01]. But Treg cells number showed no difference between the two groups. (3) Th17/Treg ratio was significantly increased in IgG4-RD patients [0.29(0.16-0.46) vs. 0.15(0.08-0.23), P<0.01], and it was positively correlated with IgG4-RD response index score(r=0.491, P<0.01). (Table 1).

Table 1.

Comparation of absolute number and percentage of peripheral blood lymphocyte subsets between IgG4-RD patients(n=31) and healthy controls (n=30).

cell subsetsIgG4-RD (n=31)HC(n=30)P valueB150.59(120.14-212.38)203.27(152.90-244.27)0.089B%8.74(6.46-11.45)10.03(8.26-13.21)0.059NK261.98(178.82-303.08)290.83(179.93-451.45)0.175NK%13.14(9.92-18.10)16.50(11.24-21.75)0.105CD3+T1357.44(992.00-1844.82)1305.81(978.24-1597.94)0.708 CD3+T%72.62(69.32-76.96)71.62(64.97-75.25)0.135CD8+T436.40(342.71-596.86)513.50(359.73-620.53)0.665CD8+T%24.26(19.48-31.27)26.50(20.67-32.90)0.535CD4+T741.00(562.78-1095.52)664.50(585.52-789.97)0.428CD4+T%45.00(33.97-51.48)39.36(33.78-43.30)0.032Th1162.32(108.11-216.61)144.27(81.52-161.66)0.094Th1%19.00(15.24-25.54)18.46(14.86-24.27)0.644Th27.82(5.35-11.78)8.25(5.32-10.87)0.817Th2%1.00(0.76-1.27)1.24(0.89-1.64)0.399Th177.90(5.20-12.23)5.60(3.12-8.47)0.010Th17%1.13(0.70-1.55)0.77(0.43-1.07)0.026Treg24.45(19.76-44.79)34.55(27.29-46.57)0.076Treg%3.37(2.82-5.65)4.96(4.18-6.34)0.003Th1/Th220.00(13.78-36.36)14.97(10.31-21.58)0.135Th1/Treg5.72(2.92-8.86)3.68(2.53-4.77)0.021Th2/Treg0.27(0.16-0.52)0.22(0.15-0.32)0.199Th17/Treg0.29(0.16-0.46)0.15(0.08-0.23)0.002

Conclusion:

Th17/Treg immune disorder exists in IgG4-RD patients, and it is related to the disease activity, indicating that Th17/Treg imbalance may be an important pathogenesis of IgG4-RD.

References:

[1]Kamisawa T, Zen Y, Pillai S, et al. IgG4-related disease[J]. Lancet, 2015, 385(9976): 1460-1471.

Disclosure of Interests:

None declared

Impact of recurrent outbreaks of Ebola virus disease in Africa: a meta-analysis of case fatality rates

OBJECTIVES

Between 2010 and 2020, Africa witnessed several outbreaks of Ebola virus disease (EVD), each presenting with varying case fatality rate (CFR) and other socio-economic impacts. This study aims to summarize the CFR and identify potential factors that influenced the severity of EVD outbreaks in Africa.

STUDY DESIGN

This was a systematic review and meta-analysis of EVD outbreaks published between January 2010 and March 2020, using Web of Science, Scopus, and PubMed databases.

METHODS

Only English-language articles and reports, including the number of cases and deaths during the outbreak in Africa, were considered. The quality of the included articles was assessed using Murad's quality assessment tool. The analysis was conducted using Stata (version 12), pooled effect sizes were calculated using the random-effects model, and heterogeneity was tested for using the I² statistic.

RESULTS

Thirteen studies with 32,300 cases and 13,727 deaths were identified, whose pooled CFR was 60% (95% confidence interval [CI]: 47-73%). The most EVD-affected countries were the Democratic Republic of Congo with five outbreaks and a pooled CFR of 65% (95% CI: 59-71%), followed by Uganda with three outbreaks and CFR of 83% (95% CI: 60-99%). Zaire ebolavirus caused the most outbreaks (10), with a CFR of 58% (95% CI: 45-71%). Besides, outbreaks with fewer than 1000 cases reported a higher CFR rate (65%, 95% CI: 54-75%) compared with those with more cases (51%, 95% CI: 33-69%).

CONCLUSION

The study has revealed a considerably high CFR caused by the recurrent EVD outbreaks in Africa. It also notes an implementation gap in the prevention and control strategies and thus identifies a need to strengthen the surveillance systems and response mechanisms to enable early detection and prompt control of future outbreaks.

The distinctive characteristics of the micro-vasculature and immune cell infiltration in cystic pancreatic neuroendocrine tumors

PURPOSE

Hypervascularity is a main characteristic of pancreatic neuroendocrine tumors (PanNETs), and cystic PanNETs (CPanNETs) are unique type of PanNETs in which the microenvironment remains unknown. We aim to compare the micro-vasculature features and immune cell infiltration between CPanNETs and solid PanNETs (SPanNETs).

METHODS

Data of 301 SPanNET and 36 CPanNET patients from a high-volume institution were evaluated. CD4, CD8, CD11c, CD15, CD20, CD68, CD34 and α-SMA expression levels were assessed by immunohistochemistry and immunofluorescent double staining. The microvessel density (MVD) and microvessel integrity (MVI) were examined.

RESULTS

MVD and MVI expression levels in CPanNETs were significantly higher than those in SPanNETs (p = 0.025 and 0.0092, respectively). CPanNETs had higher proportions of T1 (p = 0.023) and G1 (p = 0.052) than SPanNETs. In SPanNETs, higher MVD occurred in stages T1, N0 and G1 than in the T2/T3, N1 and G2 subgroups. In CPanNETs, CD34-MVD was uncorrelated with the T stage or grade. Higher CD34-MVD, but not MVI, was associated with better DFS (HR 0.3209, 95% CI 0.1259-0.8176, p = 0.004). There were significantly more peritumoral infiltrating immune cells than their intratumoral counterparts (p < 0.001 for each) in CPanNETs and SPanNETs. The mean number of peritumoral CD68 + TAM in CPanNETs was significantly lower than that in SPanNETs (p = 0.008). The counts of other peritumoral immune cells did not significantly differ between CPanNETs and SPanNETs.

CONCLUSIONS

CPanNETs had a microenvironment distinct from that of SPanNETs, including higher CD34-MVD, higher MVI and lower TAM. This specific microenvironment structure may partially help predicting the prognosis of patients with PanNET.

Endoscope-controlled maxillary sinus floor elevation: a review of the literature

A systematic review of the literature was conducted to assess the safety and efficacy of endoscope-assisted maxillary sinus elevation. PubMed, Embase, Web of Science, and the Cochrane database were searched for articles in English. Published studies involving patients who had undergone endoscope-assisted maxillary sinus floor augmentation were selected. The validity of the included articles was evaluated. After going through full texts, a total of 12 studies met the eligibility criteria and were included. It was concluded that endoscope-controlled maxillary sinus floor elevation was a viable and beneficial method, providing direct visualisation of the integrity of the mucosa and placing of bone graft material. The endoscope could be inserted into the maxillary sinus lumen, subantral space below the Schneiderian membrane, or through the alveolar crest. With the endoscope, perforations can be detected and managed precisely. However, high-quality clinical trials are still needed to validate the predictability and advantages of this surgical procedure.

Retraction notice to "30MO ORIENT-3: A randomized, open-label, phase III study of sintilimab versus docetaxel in previously treated advanced/metastatic squamous non-small cell lung cancer (sqNSCLC)": [Annals of Oncology Volume 31, Supplement 7, December 2020, Page S1428]

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article was retracted at the request of the authors. The authors of this abstract have advised that full agreement between authors and sponsors on publication of the abstract has not been reached and they are therefore unable to publish this data at present.

Action of Bacillus natto 16 on deoxynivalenol (DON) from wheat flour

AIMS

The aim of this research is to study the removal characteristics and evaluate the detoxify action of deoxynivalenol by Bacillus natto 16 in wheat flour as food or feed.

METHODS AND RESULTS

The content of deoxynivalenol was determined using ELISA by testing the deoxynivalenol removal rate, and the influence of culture supernatant, intracellular substances, crude enzyme and cell wall on the deoxynivalenol in wheat flour was studied. The effect of bacterial components on the removal of deoxynivalenol was studied in the artificial gastrointestinal environment to simulate the digestion of food. Secondary metabolites were analysed by high-performance liquid chromatography in tandem with mass spectrometry (HPLC-MS). The cell wall can reduce the content of deoxynivalenol in the sample by adsorption, the influence of culture supernatant, intracellular substances and crude enzyme can convert deoxynivalenol into substances with a lower molecular weight. Bacterial components have no effect on deoxynivalenol in wheat flour in simulated gastric fluid (SGF) and have a certain removal effect on deoxynivalenol, which is closely related to intestinal digestion time and pH, in simulated intestinal fluid.

CONCLUSIONS

Experimental results indicate that the removal of deoxynivalenol by B. natto 16 includes adsorption and biodegradation, SGF would invalidate the deoxynivalenol removal activity of B. natto 16's components.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our study showed that as an edible probiotic bacterium, B. natto 16 can effectively remove deoxynivalenol from wheat flour as food or feed, and can be used as a new deoxynivalenol -detoxifying microbe. The results of this research could provide the theory foundation for further development and application of B. natto 16.

Infant sugar sweetened beverage and 100% juice consumption: Racial/ethnic differences and links with fathers' consumption in a longitudinal cohort

The consumption of sugar-sweetened beverages (SSB) and 100% juice before age 12 months is discouraged. We examine racial/ethnic differences in SSB and 100% juice consumption when infants were 6- and 12-months old and examine links between fathers’ and infants’ beverage consumption. Participants were from a longitudinal cohort of infants and their parents (recruited 2016–2018), followed from birth until the child was 24 months. In 2020, we analyzed data collected when infants were 6- (N = 352 infants and 168 fathers) and 12-months (N = 340 infants and 152 fathers) old. Based on maternal report, 13% of infants consumed 100% juice at 6 months and 31% at 12 months. Two percent of infants consumed SSB at 6 months and 7% at 12 months. In models adjusting for income and education, Black/African American (Black/AA) and Hispanic infants were 5–6 times as likely at 6 months and 3 times as likely at 12 months to consume 100% juice compared with non-Hispanic white and Asian infants. At 12 months, Black/AA and Hispanic infants were 6–7 times as likely to consume SSB than non-Hispanic white and Asian infants after adjusting for covariates. In unadjusted models, infants were more likely to consume 100% juice and SSB at 12 months when their fathers were high consumers (>12times/month) of the beverage; effects were no longer significant after adjusting for income, race/ethnicity, education and maternal beverage consumption. Results highlight the need to implement culturally responsive interventions promoting healthy beverage consumption in infants prior to birth and should concurrently target fathers, in addition to mothers.

Semi-industrial production of a minimally processed infant formula powder using membrane filtration

Infant formula (IF) is submitted to several heat treatments during production, which can lead to denaturation or aggregation of proteins and promote Maillard reaction. The objective of this study was to investigate innovative minimal processing routes for the production of first-age IF powder, thus ensuring microbial safety with minimal level of protein denaturation. Three nutritionally complete IF powders were produced at a semi-industrial scale based on ingredients obtained by fresh bovine milk microfiltration (0.8 and 0.1-µm pore size membranes). Low-temperature vacuum evaporation (50°C) and spray-drying (inlet and outlet temperatures of 160 and 70°C, respectively) were conducted to produce the T- formula with no additional heat treatment. The T+ formula was produced with a moderate heat treatment (75°C for 2 min) applied before spray-drying, whereas the T+++ formula received successive heat treatments (72°C for 30 s on the milk; 90°C for 2-3 s before evaporation; 85°C for 2 min before spray-drying), thus mimicking commercial powdered IF. Protein denaturation and Maillard reaction products were followed throughout the production steps and the physicochemical properties of the powders were characterized. The 3 IF powders presented satisfactory physical properties in terms of a_w, free fat content, glass transition temperature, and solubility index, as well as satisfactory bacteriological quality with a total flora <10³ cfu/g and an absence of pathogens when a high level of bacteriological quality of the ingredients was ensured. Protein denaturation occurred mostly during the heat treatments of T+ and T+++ and was limited during the spray-drying process. The IF powder produced without heat treatment (T-) presented a protein denaturation extent (6 ± 4%) significantly lower than that in T+++ (58 ± 0%), but not significantly different from that in T+ (10 ± 4%). Although T- tended to contain less Maillard reaction products than T+ and T+++, the Maillard reaction products did not significantly discriminate the infant formulas in the frame of this work. The present study demonstrated the feasibility of producing at a semi-industrial scale an infant formula being bacteriologically safe and containing a high content of native proteins. Application of a moderate heat treatment before spray-drying could further guarantee the microbiological quality of the IF powders while maintaining a low protein denaturation extent. This study opens up new avenues for the production of minimally processed IF powders.

[A real-world study of 176 cases with aplastic anemia treated in outpatient]

Objective: To explore the diagnostic process and outcomes of patients with aplastic anemia (AA) who received outpatient treatment in a real-world setting. Methods: The diagnostic processes, treatment regimens, and outcomes of 176 patients with AA treated in outpatient centers from January 2018 to December 2019 were reviewed. Results: The median interval from the onset of symptoms to the first visit was 7 (5-120) months. Complaints during the first visit included bleeding (52.3% ) , anemia (51.7% ) , and infection (6.8% ) . For diagnosis, 168 patients (95.5% ) underwent bone marrow aspiration; however, only 22 of them (17.1% ) consented aspiration in multiple sites (sternum) . The completion rate of bone marrow biopsy was 85.1% (143/168) ; flow immunophenotype and karyotype analyses were performed on 59.5% (100/168) and 58.9% (99/168) of AA patients, respectively, and the culture of clonal forming units by bone marrow mononuclear cells was performed on 26.8% (45/168) of AA patients. The most preferred regimen was cyclosporine combined with androgen and levamisole (43.8% , 77 patients) , followed by cyclosporine combined with androgen (25.6% , 45 patients) . Cyclosporine alone was administered in 24 patients (13.6% ) and androgen alone in 16 patients (9.1% ) . Furthermore, 14 patients (7.9% ) did not consent to any drugs or only chose traditional Chinese medicine. The patients were divided according to the frequencies of follow-up: regular follow-up group (≥4 times/year, n=130) and irregular group (<4 times/year, n=46) . The former had a higher 6-month remission rate (52.5% vs 28.0% , P=0.005) , a greater high-quality remission rate in 12 months (40.7% vs 16.7% , P=0.027) , and a lower relapse rate in 24 months (4.4% vs 36.4% , P=0.001) . Conclusion: In real-world settings, bone marrow aspiration in multiple sites should be addressed in outpatient treatment for AA diagnostic work-up, including PNH clone screening, flow immunophenotype, chromosome karyotype analysis, and culture of clonal forming units. Patients with AA who follow regular visits were more likely to achieve high-quality remission and a lower relapse rate. Visits at least four times per year are recommended for AA patients undergoing outpatient treatment.

Profiling of donor-specific immune effector signatures in response to rituximab in a human whole blood loop assay using blood from CLL patients

Rituximab is widely used in the treatment of haematological malignancies, including chronic lymphocytic leukaemia (CLL), the most common leukaemia in adults. However, some patients, especially those with high tumour burden, develop cytokine release syndrome (CRS). It is likely that more patients will develop therapy-linked CRS in the future due to the implementation of other immunotherapies, such as CAR T-cell, for many malignancies. Current methods for CRS risk assessment are limited, hence there is a need to develop new methods. To better recapitulate an in vivo setting, we implemented a unique human whole blood "loop" system to study patient-specific immune responses to rituximab in blood derived from CLL patients. Upon rituximab infusion, both complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC) profiles were evident in CLL patient blood, coincident with CLL cell depletion. Whereas B cell depletion is induced in healthy persons in the blood loop, only patients display B cell depletion coupled with CRS. With the exception of one donor who lacked NK cells, all other five patients displayed variable B cell depletion along with CRS profile. Additionally, inhibition of CDC or ADCC via either inhibitors or antibody Fc modification resulted in skewing of the immune killing mechanism consistent with published literature. Herein we have shown that the human whole blood loop model can be applied using blood from a specific indication to build a disease-specific CRS and immune activation profiling ex vivo system. Other therapeutic antibodies used for other indications may benefit from antibody characterization in a similar setting.

Effect of Glycation on Interlamellar Bonding of Arterial Elastin

BACKGROUND

Interlamellar bonding in the arterial wall is often compromised by cardiovascular diseases. However, several recent nationwide and hospital-based studies have uniformly reported reduced risk of thoracic aortic dissection in patients with diabetes. As one of the primary structural constituents in the arterial wall, elastin plays an important role in providing its interlamellar structural integrity.

OBJECTIVE

The purpose of this study is to examine the effects of glycation on the interlamellar bonding properties of arterial elastin.

METHODS

Purified elastin network was isolated from porcine descending thoracic aorta and incubated in 2 M glucose solution for 7, 14 or 21 days at 37 °C. Peeling and direct tension tests were performed to provide complimentary information on understanding the interlamellar layer separation properties of elastin network with glycation effect. Peeling tests were simulated using a cohesive zone model (CZM). Multiphoton imaging was used to visualize the interlamellar elastin fibers in samples subjected to peeling and direct tension.

RESULTS

Peeling and direct tension tests show that interlamellar energy release rate and strength both increases with the duration of glucose treatment. The traction at damage initiation estimated for the CZM agrees well with the interlamellar strength measurements from direct tension tests. Glycation was also found to increase the interlamellar failure strain of arterial elastin. Multiphoton imaging confirmed the contribution of radially running elastin fibers to resisting dissection.

CONCLUSIONS

Nonenzymatic glycation reduces the propensity of arterial elastin to dissection. This study also suggests that the CZM effectively describes the interlamellar bonding properties of arterial elastin.