PROFILE OF CD150 EXPRESSION IN BONE MARROW CELLS OF PATIENTS WITH ACUTE MYELOID LEUKEMIA

BACKGROUND

Acute myeloid leukemia (AML) is a highly heterogeneous disease accompanied by the arrest of myeloid cell lineage differenti-ation due to accumulation of genetic abnormalities and clonal proliferation of myeloid blasts. Finding the differentially expressed molecules and studying their function within AML subgroups may help to improve diagnosis and prognosis with the aim of developing selected therapies for AML subsets. The aim of this study was to reveal the profile of CD150 cell surface expression on bone marrow (BM) cells of AML patients.

MATERIALS AND METHODS

The study was performed on samples of BM aspirates from 55 patients with primarily diagnosed AML. Flow cytometry analysis was applied for the evaluation of immunophenotype profile and CD150 cell surface expression on BM cells from AML patients.

RESULTS

Four AML subtypes (M1, M2, M3 and M5) were identified. The CD150 expression was found in 14 (25.5%) cases predominantly of AML M3 subtype. CD150 expression was detected on 43.2-83.8% of leukemia cells in AML M3. The frequency of CD150 positive cases of non-M3 AML subtypes was low: all AML M1 cases were CD150-negative, while only 1 (10.0%) of 10 patients with AML M2 and 6 (19.4%) of 31 patients with AML M5 were CD150 positive. The median percentage of CD150 positive leukemia cells and the index of mean fluorescence intensity in AML M3 cases were significantly higher than in non-M3 AML cases (p < 0.05). The CD150 expression was significantly associated with CD11c, CD11b, CD14, CD34, CD36, CD56 and HLA-DR negative expression and CD33, CD38, CD117 positive expression among the examined cohort of patients with AML M3.

CONCLUSIONS

High level of CD150 expression is a unique feature of AML M3 subtype and may serve as additional phenotype marker for the identification of blast cells with impaired maturation at the promyelocyte stage and the development of AML M3. At the same time, the revealed negative association of CD150 expression with poor prognostic factor CD56 in AML M3 subtype also allows us to suggest potential prognostic value of CD150 examination in AML patients.

M1 and M2 mAChRs activate PDK1 and regulate PKC βI and ε and the exocytotic apparatus at the NMJ

Neuromuscular junctions (NMJ) regulate cholinergic exocytosis through the M₁ and M₂ muscarinic acetylcholine autoreceptors (mAChR), involving the crosstalk between receptors and downstream pathways. Protein kinase C (PKC) regulates neurotransmission but how it associates with the mAChRs remains unknown. Here, we investigate whether mAChRs recruit the classical PKCβI and the novel PKCε isoforms and modulate their priming by PDK1, translocation and activity on neurosecretion targets. We show that each M₁ and M₂ mAChR activates the master kinase PDK1 and promotes a particular priming of the presynaptic PKCβI and ε isoforms. M₁ recruits both primed-PKCs to the membrane and promotes Munc18-1, SNAP-25, and MARCKS phosphorylation. In contrast, M₂ downregulates PKCε through a PKA-dependent pathway, which inhibits Munc18-1 synthesis and PKC phosphorylation. In summary, our results discover a co-dependent balance between muscarinic autoreceptors which orchestrates the presynaptic PKC and their action on ACh release SNARE-SM mechanism. Altogether, this molecular signaling explains previous functional studies at the NMJ and guide toward potential therapeutic targets.

PPARGC1A gene polymorphism is associated with exercise-induced fat loss

Obesity is a widespread problem within modern society, serving to increase the risk of cardiovascular, metabolic, and neurodegenerative disorders. Peroxisome proliferator-activated receptor gamma (PPARγ) and PPARγ coactivator 1 α (PGC1α) play a key role in the regulation of cellular energy metabolism and is implicated in the pathology of these diseases. This study examined the association between polymorphisms of the PPARG and PPARGC1A genes and individual variability in weight loss in response to physical activity intervention. 39 obese Ukrainian women (44.4 ± 7.5 years, BMI > 30.0 kg/m²) undertook a 3-month fitness program whilst following a hypocaloric diet (~ 1500 cal). Anthropometric and biochemical measurements took place before and after the program. Single nucleotide polymorphisms within or near PPARG (n = 94) and PPARGC1A (n = 138) were identified and expression of PPARG mRNA was measured via reverse transcription and amplification. The association between DNA polymorphisms and exercise-induced weight loss, initial body mass, biochemistry and PPARG expression was determined using one-way analysis of variance (ANOVA). The present intervention induced significant fat loss in all participants (total fat: 40.3 ± 5.3 vs 36.4 ± 5.7%; P < 0.00001). Only one polymorphism (rs17650401 C/T) within the PPARGC1A gene was found to be associated with fat loss efficiency after correction for multiple testing, with T allele carriers showing the greatest reduction in body fat percentage (2.5-fold; P = 0.00013) compared to non-carriers. PPARGC1A (rs17650401) is associated with fat loss efficiency of the fitness program in obese women. Further studies are warranted to test whether this variation is associated with fat oxidation.

Passive Q-switching of an Er, Yb:glass laser with Co:Mg(Al,Ga)2O4-based glass-ceramics

Transparent glass-ceramics (GCs) containing Co:Mg(Al,Ga)₂O₄ nanocrystals (mean diameter of 7-9 nm) are synthesized by heat treatments at 850-950°C from magnesium aluminosilicate glass nucleated by TiO₂ and doped with Ga₂O₃ and CoO. The GCs exhibit a broadband A₂4(F4)→T₁4(F4) absorption due to the Co²⁺ ions, low saturation fluence (∼0.5  J/cm²), fast recovery time of initial absorption (∼300  ns), and high laser damage threshold (∼20  J/cm²). They are used for passive Q-switching of a diode side-pumped Er,Yb:glass laser generating 3.1 mJ/20 ns pulses (peak power, 155 kW) at 1535 nm with a TEM₀₀ output mode. The Q-switching performance of the Co:Mg(Al,Ga)₂O₄-based GCs is compared with that for various Co²⁺-doped GCs and Co:MgAl₂O₄ single crystal. The prepared GCs are promising for further applications in passively Q-switched Er:YAG and other Er crystalline (or ceramic) lasers.

Cultivation of Nannochloropsis for eicosapentaenoic acid production in wastewaters of pulp and paper industry

The eicosapentaenoic acid (EPA) containing marine microalga Nannochloropsis oculata was grown in an effluent from anaerobic digestion of excess activated sludge from a wastewater treatment plant serving a combination of a pulp and a paper mill and a municipality (digester effluent, DE), mixed with the effluent of the same wastewater treatment plant. The maximum specific growth rate and photosynthesis of N. oculata were similar in the DE medium and in artificial sea water medium (ASW) but after 7 days, algae grown in the DE medium contained seven times more triacylglycerols (TAGs) per cell than cells grown in ASW, indicating mild stress in the DE medium. However, the volumetric rate of EPA production was similar in the ASW and DE media. The results suggest that N. oculata could be used to produce EPA, utilizing the nutrients available after anaerobic digestion of excess activated sludge of a pulp and paper mill.