Evaluating the anti-leishmania activity of Lucilia sericata and Sarconesiopsis magellanica blowfly larval excretions/secretions in an in vitro model

Leishmaniasis is a vector-borne disease caused by infection by parasites from the genus Leishmania. Clinical manifestations can be visceral or cutaneous, the latter mainly being chronic ulcers. This work was aimed at evaluating Calliphoridae Lucilia sericata- and Sarconesiopsis magellanica-derived larval excretions and secretions\u27 (ES) in vitro anti-leishmanial activity against Leishmania panamensis. Different larval-ES concentrations from both blowfly species were tested against either L. panamensis promastigotes or intracellular amastigotes using U937-macrophages as host cells. The Alamar Blue method was used for assessing parasite half maximal inhibitory concentration (IC ) and macrophage cytotoxicity (LC ). The effect of larval-ES on L. panamensis intracellular parasite forms was evaluated by calculating the percentage of infected macrophages, parasite load and toxicity. L. sericata–derived larval-ES L. panamensis macrophage LC was 72.57 μg/mL (65.35–80.58 μg/mL) and promastigote IC was 41.44 μg/mL (38.57–44.52 μg/mL), compared to 34.93 μg/mL (31.65–38.55 μg/mL) LC and 23.42 μg/mL (22.48–24.39 μg/mL) IC for S. magellanica. Microscope evaluation of intracellular parasite forms showed that treatment with 10 μg/mL L. sericata ES and 5 μg/mL S. magellanica ES led to a decrease in the percentage of infected macrophages and the amount of intracellular amastigotes. This study produced in vitro evidence of the antileishmanial activity of larval ES from both blowfly species on different parasitic stages and showed that the parasite was more susceptible to the ES than it\u27s host cells. The antileishmanial effect on L. panamensis was more evident from S. magellanica ES. 50 50 50 50 50 5

A dual aurora and lim kinase inhibitor reduces glioblastoma proliferation and invasion

[Display omitted] High rates of recurrence and treatment resistance in the most common malignant adult brain cancer, glioblastoma (GBM), suggest that monotherapies are not sufficiently effective. Combination therapies are increasingly pursued, but the possibility of adverse drug-drug interactions may preclude clinical implementation. Developing single molecules with multiple targets is a feasible alternative strategy to identify effective and tolerable pharmacotherapies for GBM. Here, we report the development of a novel, first-in-class, dual aurora and lim kinase inhibitor termed F114. Aurora kinases and lim kinases are involved in neoplastic cell division and cell motility, respectively. Due to the importance of these cellular functions, inhibitors of aurora kinases and lim kinases are being pursued separately as anti-cancer therapies. Using in vitro and ex vivo models of GBM, we found that F114 inhibits GBM proliferation and invasion. These results establish F114 as a promising new scaffold for dual aurora/lim kinase inhibitors that may be used in future drug development efforts for GBM, and potentially other cancers

Derivation of stem cell line UMi028-A-2 containing a CRISPR/Cas9 induced Alzheimer’s disease risk variant p.S1038C in the TTC3 gene

The UMi028-A-2 human induced pluripotent stem cell line carries a homozygous mutation (rs377155188, C>G, p.S1038C) in the tetratricopeptide repeat domain 3 (TTC3) gene that was introduced via CRISPR/Cas9 genome editing. The line was originally derived from a neurologically normal male and has been thoroughly characterized following editing. The p.S1038C variant has been shown to potentially contribute to the risk of late onset Alzheimer’s disease and is a resource to further investigate the consequences of TTC3 and this alteration in disease pathology

iPSC‐derived neurons and microglia with an African‐specific ABCA7 frameshift deletion have impaired function

Background The ATP‐binding cassette, sub‐family A (ABC1), member 7 (ABCA7) gene has been implicated as a risk factor in Alzheimer’s disease (AD) across populations. However, the risk effect of ABCA7 in African Americans (AAs) is stronger than in non‐Hispanic white (NHW) populations. We identified a 44 base pair deletion in AA significantly associated with disease (cases = 15.2%, controls = 9.74%, p = 1.414 × 10−5, Cukier, et al, 2016). The deleted allele is predicted to produce a frameshift mutation (p.Arg578Alafs), resulting in a truncated protein that may interfere with its normal functions, including APP processing and Aβ clearance. Method To further understand the mechanism by which the ABCA7 deletion may be acting, induced pluripotent stem cells (iPSC) lines were developed from the blood of two unrelated AA AD individuals heterozygous for the deletion, as well as age matched cognitively normal individuals. The iPSC lines were differentiated into cortical neurons and microglia, as both cell types endogenously express ABCA7. Result Each iPSC line generated was karyotyped and validated for pluripotency through immunocytochemical staining. RNA from the cases demonstrated that a stable RNA transcript is produced from the ABCA7 deletion allele. Preliminary results from iPSC‐derived neurons and microglia identified impaired functions in both cells types. Cortical neurons from patients produced higher levels of Aβ40 and Aβ42 compared to controls. In addition, while the patient‐derived microglia had normal rates of phagocytosis, they were impaired in the uptake and clearance of fibrillar Ab. Furthermore, when exposed to the proinflammatory stimulus lipopolysaccharide (LPS), the patient‐derived microglia had decreased cytokine responses. Conclusion This deletion in ABCA7 is an ethnic specific, pathogenic alteration in AD that may result in an increased production of toxic β‐amyloid production in neurons and a depressed ability to clear Ab and impaired responsiveness to proinflammatory signals in microglia

A risk variant in TTC3 modifies the actin cytoskeleton organization and PI3K‐Akt signaling in iPSC‐derived forebrain neurons

Abstract Background We identified a rare, nonsynonymous variant in the tetratricopeptide repeat domain 3 (TTC3) gene that segregated in a non‐Hispanic white late onset Alzheimer disease (LOAD) family (Kohli, et al, 2016). This missense alteration, rs377155188 (p.S1038C), is predicted to be deleterious and is extremely rare. Studies have reported that cortical TTC3 expression is reduced in LOAD patients and negatively correlated with AD neuropathology. Method To understand the mechanism by which the TTC3 p.S1038C may contribute to LOAD risk, CRISPR/Cas9 genome edited induced pluripotent stem cells (iPSCs) were developed that were homozygous for the variant to examine cellular and transcriptional consequences in iPSC‐derived neuronal cells (Laverde‐Paz, et al, 2021). Result Quantitative PCR and western blot analysis demonstrated that TTC3 levels were decreased in edited compared to unedited iPSCs, as well as differentiated neurons. In growing neuronal precursor cells (NPCs), cells with the TTC3 variant recovered more quickly from a scratch wound. Since there is evidence that modulation of TTC3 affects neurite growth, morphological measures of axon formation were assessed using the Incucyte Zoom. Studies demonstrate an increase in neurite outgrowth, which phenotypically corresponds with previous studies of a decrease in TTC3 function. This phenotype was tempered by treatment with Cytochalasin D, an inhibitor of actin polymerization. Additionally, TTC3 ubiquitinates phosphorylated AKT and regulates AKT signaling. The edited cells were found to have an increase in phosphorylated AKT (pAKT) relative to total AKT. RNA‐seq of day 70 neurons identified 979 genes that were differentially expressed (FDR<0.05). This included known AD genes (BACE1) and genes in AD GWAS loci (ADAMTS1, MAF, NCK2). KEGG pathway analysis identified differential expression in PI3K‐Akt signaling pathway components, in which TTC3 has been previously implicated, as well as the axon guidance pathway, the GABAergic synapse pathway, and the Wnt signaling pathway. Conclusion Combined, these results suggest that the TTC3 p.S1038C variant causes a loss of function. Utilizing a CRISPR genome edited iPSC carrying a homozygous alteration in TTC3, we were able to identify potential mechanisms by which TTC3 may contribute to LOAD risk

Generation of an induced pluripotent stem cell line (UMi043-A) from an African American patient with Alzheimer’s disease carrying an ABCA7 deletion (p.Arg578Alafs)

The ATP-binding cassette, subfamily A (ABC1), member 7 (ABCA7) gene is associated with Alzheimer’s disease (AD) risk in populations of African, Asian, and European ancestry1-5. Numerous ABCA7 mutations contributing to risk have been identified, including a 44 base pair deletion (rs142076058) specific to individuals of African ancestry and predicted to cause a frameshift mutation (p.Arg578Alafs) (Cukier et al., 2016). The UMi043-A human induced pluripotent stem cell line was derived from an African American individual with AD who is heterozygous for this deletion and is a resource to further investigate ABCA7 and how this African-specific deletion may influence disease pathology

Uncovering the Role of an ABCA7 Frameshift Deletion in African American Alzheimer’s Disease Cellular Pathology

Abstract Background The ATP Binding Cassette Subfamily A Member 7 (ABCA7) gene is a risk factor for Alzheimer’s disease (AD). While ABCA7 has been implicated as a genetic determinant of AD across populations, the risk effect is the strongest in African Americans (AAs). We previously identified a common 44 base pair deletion in ABCA7 (p.Arg578Alafs) that is predicted to truncate the protein and is significantly associated with AD in AAs (frequency in cases = 15.2%, cognitively unimpaired (CU) = 9.74%, p = 1.41×10 −5 ). Clinically, deletion homozygotes are similar to deletion heterozygotes, supporting dominant gain‐of‐function as a putative disease‐causing mechanism. We sought to determine if the deletion transcript is stable and if the truncated protein is expressed as steps to understanding the mechanism leading to AD risk. Method RT‐PCR analysis of heterozygotes was conducted to assess the stability of the deletion transcript. FLAG‐tagged Arg578Alafs and wildtype ABCA7 vectors were constructed then overexpressed in HEK293 APPsw cells. Western blot analysis of FLAG‐Arg578Alafs was performed to determine if the deletion produces a truncated protein. Induced pluripotent stem cell (iPSC) lines from six AA individuals with AD bearing the Arg578Alafs mutation (three heterozygous; three homozygous) were created in pair with isogenic CRISPR‐corrected control lines. These iPSC lines were validated for pluripotency, genomic stability, and lack of off‐target editing. The isogenic ABCA7 deletion and CRISPR‐corrected control iPSC lines will be differentiated into microglia and neurons and functionally assessed for cell type‐specific AD phenotypes. Result Initial results comparing AD patients to CU individuals show that patient‐derived microglia have normal rates of phagocytosis but are impaired in the uptake and clearance of fibrillar Aβ. RT‐PCR analysis of the deletion in heterozygotes demonstrates that a stable RNA transcript is expressed from the ABCA7 deletion allele. Western blot analysis of overexpressed FLAG‐Arg578Alafs shows that the truncated protein is expressed, albeit at low levels compared to the wildtype protein. Conclusion This ABCA7 deletion produces a stable transcript which appears to be translated into low levels of protein. This supports a potential gain of function as the disease risk mechanism. Studies in isogenic lines will further elucidate the functional effects of this ABCA7 deletion on AD pathology in AAs