[The Efficacy and Safety of Daratumumab-Based Regimen in Treatment of Multiple Myeloma Patients with Renal Impairment].

OBJECTIVE: To investigate the efficacy and safety of daratumumab in treatment of multiple myeloma (MM) patients with renal impairment (RI). METHODS: The clinical data of 15 MM patients with RI who received daratumumab-based regimen from January 2021 to March 2022 in three centers were retrospectively analyzed. Patients were treated with daratumumab or daratumumab combined with dexamethasone or daratumumab combined with bortezomib and dexamethasone and the curative effect and survival were analyzed. RESULTS: The median age of 15 patients was 64 (ranged 54-82) years old. Six patients were IgG-MM, 2 were IgA-MM,1 was IgD-MM and 6 were light chain MM. Median estinated glomerular filtration rate (eGFR) was 22.48 ml/(min·1.73 M2). Overall response rate of 11 patients with MM was 91% (≥MR), including 1 case of stringent complete response (sCR), 2 cases of very good partial response (VGPR), 3 cases of partial response (PR) and 4 cases of minor response (MR). The rate of renal response was 60%(9/15), including 4 cases of complete response (CR), 1 case of PR and 4 cases of MR. A median time of optimal renal response was 21 (ranged 7-56) days. With a median follow-up of 3 months, the median progression-free survival and overall survival of all patients were not reached. After treatment with daratumumab-based regimen, grade 1-2 neutropenia was the most common hematological adverse reaction. Non-hematological adverse reactions were mainly infusion-related adverse reactions and infections. CONCLUSION: Daratumumab-based regimens have good short-term efficacy and safety in the treatment of multiple myeloma patients with renal impairment.

Overexpression of the immediate early response 5 gene increases the radiosensitivity of HeLa cells.

The effects of the immediate early response 5 (IER5) gene on the sensitivity of HeLa cells to radiation remain unclear. In the present study, stably transfected HeLa cells resulting in the knockdown or overexpression of IER5 were investigated. In addition, xenografts of normal, IER5-silenced and -overexpressed HeLa cells were injected into nude mice and examined. The results demonstrated that the radiosensitivity of the IER5-overexpressed HeLa cells was significantly increased compared with that of the normal and IER5-silenced cells. The upregulation of IER5 effectively decreased cell proliferation and IER5 silencing promoted cell proliferation compared with that in the normal HeLa cells. Following irradiation of the cells with IER5 knockdown, cell cycle was arrested at the G2/M phase and an increase in the proportion of S phase cells was observed. By contrast, the overexpression of IER5 led to an increase in the proportion of G1 phase cells. Furthermore, the upregulation of IER5 inhibited tumor growth in vivo. The present findings demonstrate that the IER5 gene affects the radiosensitivity of HeLa cells and serves an important role in cell proliferation, suggesting that this gene may be a potential radiotherapeutic target in cervical cancer.

[Effect of rhubarb on neonatal rats with bronchopulmonary dysplasia induced by hyperoxia].

OBJECTIVE: To study the effect of rhubarb on neonatal rats with bronchopulmonary dysplasia (BPD) induced by hyperoxia. METHODS: A total of 64 rats (postnatal day 4) were randomly divided into four groups: air control, rhubarb control, hyperoxia model, and hyperoxia+rhubarb (n=16 each). The rats in the hyperoxia model and hyperoxia+rhubarb groups were exposed to hyperoxia (60% O2) to establish a BPD model. The rats in the rhubarb control and hyperoxia+rhubarb groups were given rhubarb extract suspension (600 mg/kg) by gavage daily. The pathological changes of lung tissue were evaluated by hematoxylin-eosin staining on postnatal days 14 and 21. The content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) were measured by spectrophotometry. The mRNA and protein expression levels of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were determined by RT-PCR and Western blot respectively. RESULTS: The hyperoxia model group showed reduced alveolar number, increased alveolar volume, and simplified alveolar structure, which worsened over the time of exposure to hyperoxia. These pathological changes were significantly reduced in the hyperoxia+rhubarb group. On postnatal days 14 and 21, compared with the air control and rhubarb control groups, the hyperoxia model group had significantly reduced radical alveolar count (RAC), significantly reduced activity of SOD in the lung tissue, and significantly increased content of MDA and mRNA and protein expression levels of TNF-α and IL-6 (P<0.05). Compared with the hyperoxia model group, the hyperoxia+rhubarb group had significantly increased RAC, significantly increased activity of SOD in the lung tissue, and significantly reduced content of MDA and mRNA and protein expression levels of TNF-α and IL-6 (P<0.05). CONCLUSIONS: Rhubarb may play a protective role in rats with BPD induced by hyperoxia through inhibiting inflammatory response and oxidative stress.

Heat Shock Factor HsfA1a Is Essential for R Gene-Mediated Nematode Resistance and Triggers H2O2 Production1.

Plants generate reactive oxygen species (ROS) in the apoplast in response to pathogen attack, especially following resistance (R) gene-mediated pathogen recognition; however, the mechanisms activating ROS generation remain unknown. Here, we demonstrate that RKN (Meloidogyne incognita) infection rapidly induces ROS accumulation in the roots of tomato (Solanum lycopersicum) plants that contain the R gene Mi-1.2 but rarely induces ROS accumulation in the susceptible or Mi-1.2-silenced resistant genotypes. RNK also induces the hypersensitive response, a form of programmed cell death, in Mi-1.2 plants. RKN induces the expression of numerous class-A heat shock factor (HsfA) genes in resistant tomato plants. Silencing HsfA1a compromises Mi-1.2-mediated resistance, apoplastic H2O2 accumulation, and the transcription of whitefly induced 1 (Wfi1), which encodes a respiratory burst oxidase homolog. HsfA1a regulates Wfi1 transcription by binding to the Wfi1 promoter, and silencing of Wfi1 compromises Mi-1.2-mediated resistance. HsfA1a and Wfi1 are involved in Mi-1.2-triggered Hsp90 accumulation and basal defense in susceptible tomato. Thus, HsfA-1aWfi1-dependent ROS signaling functions as a crucial regulator of plant defense responses.

Interactions between 2-Cys peroxiredoxins and ascorbate in autophagosome formation during the heat stress response in Solanum lycopersicum.

2-Cys peroxiredoxins (2-CPs) function in the removal of hydrogen peroxide and lipid peroxides but their precise roles in the induction of autophagy have not been characterized. Here we show that heat stress, which is known to induce oxidative stress, leads to the simultaneous accumulation of transcripts encoding 2-CPs and autophagy proteins, as well as autophagosomes, in tomato (Solanum lycopersicum) plants. Virus-induced gene silencing of the tomato peroxiredoxin genes 2-CP1, 2-CP2, and 2-CP1/2 resulted in an increased sensitivity of tomato plants to heat stress. Silencing 2-CP2 or 2-CP1/2 increased the levels of transcripts associated with ascorbate biosynthesis but had no effect on the glutathione pool in the absence of stress. However, the heat-induced accumulation of transcripts associated with the water-water cycle was compromised by the loss of 2-CP1/2 functions. The transcript levels of autophagy-related genes ATG5 and ATG7 were higher in plants with impaired 2-CP1/2 functions, and the formation of autophagosomes increased, together with an accumulation of oxidized and insoluble proteins. Silencing of ATG5 or ATG7 increased the levels of 2-CP transcripts and protein but decreased heat stress tolerance. These results demonstrate that 2-CPs fulfil a pivotal role in heat stress tolerance in tomato, via interactions with ascorbate-dependent pathways and autophagy.

DWARF overexpression induces alteration in phytohormone homeostasis, development, architecture and carotenoid accumulation in tomato.

Brassinosteroids (BRs) play a critical role in plant growth, development and stress response; however, genetic evidence for the BR-mediated integrated regulation of plant growth still remains elusive in crop species. Here, we clarified the function of DWARF (DWF), the key BR biosynthetic gene in tomato, in the regulation of plant growth and architecture, phytohormone homeostasis and fruit development by comparing wild type, d^(im), a weak allele mutant impaired in DWF, and DWF-overexpressing plants in tomato. Results showed that increases in DWF transcripts and endogenous BR level resulted in improved germination, lateral root development, CO2 assimilation and eventually plant growth as characterized by slender and compact plant architecture. However, an increase in DWF transcript down-regulated the accumulation of gibberellin, which was associated with decreases in leaf size and thickness. BRs positively regulated lateral bud outgrowth, which was associated with decreased transcript of Aux/IAA3, and the ethylene-dependent petiole bending and fruit ripening. Notably, overexpression of DWF did not significantly alter fruit yield per plant; however, increases by 57.4% and 95.3% might be estimated in fruit yield per square metre in two transgenic lines due to their compact architecture. Significantly, BR level was positively related with the carotenoid accumulation in the fruits. Taken together, our results demonstrate that BRs are actively involved in the regulation of multiple developmental processes relating to agronomical important traits.

[Cloning of VH and VL Gene of Human anti-IL1RAP McAb and Construction of Recombinant Chimeric Receptor].

OBJECTIVE: To clone the variable region genes of human anti-IL1RAP (IL-1 receptor accessory protein) monoclonal antibodies (McAb) and to construct IL1RAP chimeric antigen receptors (CARs). METHODS: The VH and VL DNA of IL1RAP single chain antibodies were amplified by RACE and overlap extension PCR from total RNA extracted from 3H6E10 and 10D8A7 hybridoma and ligated into specific IL1RAP single-chain variable fragments (scFv). CD8α transmembrane domain, CD137 intracellular domain, TCR ζ chain, human CD8α signal peptide and scFv-anti-IL1RAP were cloned into plasmid LV-lac. Recombinant lentiviruses were generated by co-transfection of recombinant plasmid LV-lac, pMD2. G, and psPAX2 helper vectors into 293FT packing cells. RESULTS: The VH and VL genes of 2 human anti-IL1RAP McAb were acquired. The 3H6E10 VH and VL genes consisted of 402 bp and 393 bp encoding 134 and 131 aminoacid residues, respectively; 10D8A7 VH and VL genes consisted of 423 bp and 381 bp encoding 141 and 127 amine acid residues, respectively. Recombinant expression vertors LV-3H6E10 scFv-ICD and LV-10D8A7 scFv-ICD (ICD: CD8α transmembrane domain-CD137 intracellular domain-TCR ζ chain) were constructed. The target fragments were demonstrated by sequencing analysis. Recombinant plasmids were transfected into 293FT cells and lentiviral particles were acquired. CONCLUSION: Human anti-IL1RAP recombinant receptors are constructed successfully and lay a good foundation for the construction of IL1RAP-CAR killer T cell vaccine.

[Preparation and Assessment of IL1RAP Monoclonal Antibody].

OBJECTIVE: To prepare and identify human monoclonal antibody against IL-1 receptor accessory protein (IL1RAP), which is a new identified surface marker for leukemia stem cells (LSC). METHODS: BALB/c mice were inoculated intraperitoneally with hybridoma cells (3H6E10, 10D8A7) and their ascites were collected. The monoclonal antibody against hu-IL1RAP specifically was purified from ascites, the nondenaturing-PAGE, ELISA and Western blot were used to detect the purity, titer and sensitivity of antibody. RESULTS: Two purified antibodies were obtained and named as 3H6E10 McAb and 10D8A7 McAb, whose purity was 95% and 94% respectively. The titer of two purified monoclonal antibodies was 1 : 81000 and specific conjugation of IL1RAP purified protein and endogenous protein from normal people and leukemia patients with purified antibodies were confirmed. CONCLUSION: The purified monoclonal antibodies which can specifically bind to hu-IL1RAP are successfully prepared, thus providing novel way to effectively clear LSC in the future.

IL1RAP as a surface marker for leukemia stem cells is related to clinical phase of chronic myeloid leukemia patients.

Chronic myeloid leukemia (CML) is a clonal disease from hematopoietic stem cells. Surviving leukemia stem cells (LSCs) and progenitor cells are a potential source for CML relapse and progression. Recent data reported that IL-1 receptor accessory protein (IL1RAP) gene was differentially expressed in CML versus normal stem and progenitor cells. However, whether the level of IL1RAP is associated with clinical phases of CML, and correlations between IL1RAP expression and detections of diagnosis is still unclear. Here we demonstrated that IL1RAP was up-regulated in CD34+ and CD34+CD38- cells which highly enriched with stem cells. Furthermore, IL1RAP expression in CD34+CD38- cells was tightly consistent with the generation of BCR-ABL fusion gene and Philadelphia chromosome. Importantly, we found that the level of IL1RAP increased with disease progression from chronic phase (CP) into accelerated phase (AP) and blast phase (BP), which was investigated not only in new diagnosed CML patients but also in patients treated with tyrosine kinase inhibitors (TKI) and hydroxyurea. Negative correlation was detected between IL1RAP expression and neutrophil (NE), whereas no relation was found in white blood cell (WBC), lymphocyte (LY), red blood cell (RBC), platelet (PLT), age or gender of CML patients. In conclusion, we identified IL1RAP as a surface marker of LSCs may be a potential indicator for CML clinical phases.

[Construction of hybridoma cells with IL1RAP as a new marker for leukemia stem cells and detection of its monoclonal antibody].

This study was aimed to prepare and identify human monoclonal antibody against IL-1 receptor accessory protein (IL1RAP), which is a new identified surface marker for leukemia stem cell (LSC), BALB/c mice were immunized with recombinant hu-IL1RAP and the spleen cells from immunized mice were fused with SP2/0 myeloma cells by conventional hybridoma technique. Positive hybridoma cells were selected and cultured. ELISA and Western blot were used to detect the type, titer and sensitivity of antibody. Peripheral blood mononuclear cells were isolated and used to test the antibody specificity. The results showed that 8 hybridoma cell lines able to stably secrete IL1RAP monoclonal antibodies were obtained and named 3H6E10, 4B6A6, 8G11B5, 9E9F2, 10D8A7, 1C7H7, 1D7G11 and 2D3D3 respectively. These monoclonal antibodies belonging to IgG1/κ type could specifically bind to IL1RAP from peripheral blood mononuclear cells. It is concluded that the hybridoma cell lines with stable secretion of IL1RAP monoclonal antibodies is successfully constructed, thus providing novel ways to effectively clear LSC in the future.

Selective detection of superoxide anion radicals generated from macrophages by using a novel fluorescent probe.

Quantitation of superoxide radical (O (2)(-).) production at the site of radical generation remains challenging. A simple method to detect nanomolar to micromolar levels of superoxide radical in aqueous solution has been developed and optimized. This method is based on the efficient trapping of O(2)(-). using a novel fluorescent probe (2-chloro-1,3-dibenzothiazolinecyclohexene), coupled with a spectra character-signaling increase event. A high-specificity and high-sensitivity fluorescent probe was synthesized in-house and used to image O(2)(-). in living cells. Better selectivity for O(2)(-). over competing cellular reactive oxygen species and some biological compounds illustrates the advantages of our method. Under optimal conditions, the linear calibration range for superoxide anion radicals was 5.03 x 10(-9)-3.33 x 10(-6) M. The detection limit was 1.68 x 10(-9) M. Fluorescence images of probe-stained macrophages stimulated with 4beta-phorbol 12-myristate 13-acetate were obtained successfully using a confocal laser scanning microscope.