The prognostic significance of minimal residual disease in adult Egyptian patients with precursor acute lymphoblastic leukemia

AbstractBackgroundMinimal residual disease (MRD) studies in adult acute lymphoblastic leukemia (ALL) give highly significant prognostic information superior to other standard criteria as age, gender and total leucocytic count (TLC) in distinguishing patients at high and low risk of relapse.ObjectivesWe aimed to determine the value of MRD monitoring by flowcytometry (FCM) in predicting outcome in adult Precursor ALL patients.Patients and methodsBone marrow (BM) samples were analyzed by 4-color FCM collected at diagnosis and after induction therapy (MRD1) to correlate MRD positivity with disease free survival (DFS) and overall survival (OS).ResultsStudy included 57 adult ALL patients (44 males and 13 females) with a median age of 22years (18–49). DFS showed no significant difference with age, gender and initial TLC (p=0.838, 0.888 and 0.743, respectively). Cumulative DFS at 2years was 34% for B-lineage ALL (n: 35) and 57% for T-lineage ALL (n: 18) (p=0.057). Cumulative DFS at 2years was 7% for MRD1 positive (high risk, HR) versus 57% for MRD1 negative patients (Low risk, LR) (p<0.001). Cumulative DFS at 2years was 29% for HR patients (n: 26) versus 55% for LR (n: 27) according to GMALL classification (p=0.064). Cumulative OS did not differ according to age, gender and TLC (p=0.526, 0.594 and 0.513, respectively). Cumulative OS at 2years was 36% for B ALL (n: 39) versus 77% for TALL (n: 18) (p=0.016) and was 49% for Philadelphia chromosome (Ph) negative patients versus 0% for Ph-positive patients (p<0.001). Regarding MRD1, OS at 2years was 18% for MRD1 HR (n: 17) versus 65% for MRD1 LR (n: 38) (p<0.001). OS was 35% for high-risk patients (n: 30) and 62% for low-risk patients (n: 27) classified according to GMALL risk stratification (p=0.017).ConclusionMRD by FCM is a strong independent predictor of outcome in terms of DFS and OS and is a powerful informative parameter in guiding individual treatment in ALL patients

Synergism between Streptomyces viridosporus HH1 and Rhizophagus irregularis Effectively Induces Defense Responses to Fusarium Wilt of Pea and Improves Plant Growth and Yield

Fusarium wilt is a detrimental disease of pea crop, resulting in severe damage and a reduction in its yield. Developing synergistically enhanced bioagents for disease management and growth promotion is pivotal for food safety, security, and sustainability. In this study, biocontrol potential of treating pea plants with Streptomycesviridosporus HH1 and/or their colonization with Rhizophagusirregularis against infection with Fusarium wilt was investigated. Impacts on the expression profiles of defense-related genes, biochemical, and ultrastructural levels, as well as the growth and yield of pea plants in response to these treatments, were also investigated. Data obtained indicated the antifungal activity of S. viridosporus HH1 against F. oxysporum f.sp. pisi in vitro. Furthermore, the GC-MS analysis revealed production of different bioactive compounds by S. viridosporus HH1, including 2,3-butanediol, thioglycolic acid, and phthalic acid. The results from the greenhouse experiment exhibited a synergistic biocontrol activity, resulting in a 77% reduction in disease severity in pea plants treated with S. viridosporus HH1 and colonized with R. irregularis. In this regard, this dual treatment overexpressed the responsive factor JERF3 (5.6-fold) and the defense-related genes &beta;-1,3-glucanase (8.2-fold) and the pathogenesis-related protein 1 (14.5-fold), enhanced the total phenolic content (99.5%), induced the antioxidant activity of peroxidase (64.3%) and polyphenol oxidase (31.6%) enzymes in pea plants, reduced the antioxidant stress, and improved their hypersensitivity at the ultrastructural level in response to the Fusarium wilt pathogen. Moreover, a synergistic growth-promoting effect was also recorded in pea plants in response to this dual treatment. In this regard, due to this dual treatment, elevated levels of photosynthetic pigments and improved growth parameters were observed in pea leaves, leading to an increment in the yield (113%). In addition, application of S. viridosporus enhanced the colonization levels with R. irregularis in pea roots. Based on the obtained data, we can conclude that treating pea plants with S. viridosporus HH1 and colonization with R. irregularis have synergistic biocontrol activity and growth-promoting effects on pea plants against Fusarium wilt. Despite its eco-safety and effectiveness, a field evaluation of this treatment before a use recommendation is quite necessary

Mycorrhizal colonization and Streptomyces viridosporus HH1 synergistically up-regulate the polyphenol biosynthesis genes in wheat against stripe rust

Abstract Background Stripe rust is considered one of the most devastating diseases of wheat all over the world, resulting in a high loss in its production. In this study, time-course changes in expression of the polyphenol biosynthesis pathways genes in wheat against stripe rust were investigated. The defense mechanisms triggered by mycorrhizal colonization and/or spraying with Streptomyces viridosporus HH1 against this disease were also investigated. Results Results obtained revealed that C3H, which is considered the key gene in lignin biosynthesis, was the most expressed gene. Furthermore, most of the chlorogenic acid and flavonoid biosynthesis genes were also overexpressed. Volcano plots of the studied genes reveal that the dual treatment led to a high significant overexpression of 10 out of the 13 studied genes. Heatmap of these genes showed that the most frequent expressed gene in response to all applied treatments along the study period was DFR, the key gene in the biosynthesis of anthocyanidins. Gene co-expression network of the studied genes showed that HQT was the most central gene with respect to the other genes, followed by AN2 and DFR, respectively. Accumulation of different flavonoids and phenolic acids were detected in response to the dual treatment, in particular, cinnamic acid, coumarin, and esculetin, which recorded the highest elevation level recording 1000, 488.23, and 329.5% respectively. Furthermore, results from the greenhouse experiment showed that application of the dual treatment led to an 82.8% reduction in the disease severity, compared with the control treatment. Conclusions We can conclude that the biosynthesis of lignin, chlorogenic acid, and flavonoids contributed to the synergistic triggering effect of the dual treatment on wheat resistance to stripe rust