Effect of dexamethasone implant on intraocular cytokines in diabetic macular edema.

Purpose: Our primary aim was to evaluate intraocular cytokines (IC) before and after dexamethasone in diabetic macular edema (DME). Our secondary aim was to study the early and late effects of single dexamethasone implant in DME. Methods: This before and after comparative study was conducted at the Department of Ophthalmology and Centre for Nanosciences at a quaternary referral center in Kerala, India, from September 2016 to September 2018. Patients underwent complete ophthalmological examination and cytokine analysis before and after dexamethasone implant. Levels of cytokines at baseline and repeat sample were studied. Results: Twenty-seven eyes (21 patients) were divided into two groups depending on time from baseline to second injection. Group 1 included patients with <3 months between the two samples - 12 (44.4%). Group 2 included patients with >3 months between the two samples -15 (55.6%). Best corrected visual acuity (BCVA) and central macular thickness (CMT) improved significantly post-dexamethasone in group 1, but not in group 2. Interleukin (IL)-4, IL-6, IL-10, vascular endothelial growth factor (VEGF), IL-1ß, interferon-gamma inducible protein-10 (IP-10), monocyte chemoattractant protein-1 (MCP-1), and IL-2 decreased post-injection in group 1. But cytokines increased post-dexamethasone in group 2, except IL-10. When compared to baseline, IL-6 reduced to half in group 1 (P-value 0.814) and it tripled in group 2 ( P-value 0.009). The level of VEGF in the first and second samples was not different in either group. Conclusion: Our study suggests that dexamethasone acts more on IC than VEGF in DME. This is significant in the first 3 months with a rebound effect on IL-6 after 3 months. Our study also suggests that repeat injection of DEX in DME should be done at 3 months to prevent deterioration of visual acuity (VA) and worsening of CMT.

Translational Significance of GMF-ß Inhibition by Indazole-4-yl-methanol in Enteric Glial Cells for Treating Multiple Sclerosis.

In the emerging context of gut-brain control of multiple sclerosis (MS), developing therapeutics targeting proinflammatory proteins controlling the gut-brain immunomodulation is welcoming. One such immunomodulator is glia maturation factor-ß (GMF-ß). GMF-ß activation following GMF-ß-ser-83 phosphorylation upregulates proinflammatory responses and exacerbates experimental autoimmune encephalomyelitis (EAE). Notably, GMF-ß-/- mice exhibited no EAE symptoms. Thus, we identified 1H-indazole-4-yl-methanol (GMFBI.1) inhibitor which blocked GMF-ß-ser-83 phosphorylation critical in EAE suppression. To establish gut GMF-ß's role in EAE in the context of gut-brain involvement in neurodegenerative diseases, we altered gut GMFBI.1 bioavailability as an index of EAE suppression. At first, we identified Miglyol 812N as a suitable biocompatible GMFBI.1 carrier compared to other FDA-approved carriers using in silico molecular docking analysis. GMFBI.1 administration in Miglyol 812N enhanced its retention/brain permeability. Subsequently, we administered GMFBI.1-Miglyol 812N by subcutaneous/oral routes at different doses with differential GMFBI.1 bioavailability in gut and brain to assess the role of local GMFBI.1 bioavailability in EAE reversal by a pharmacokinetic approach. Deprival of gut GMFBI.1 bioavailability led to partial EAE suppression despite having sufficient GMFBI.1 in circulation to inhibit brain GMF-ß activity. Restoration of gut GMFBI.1 bioavailability led to complete EAE reversal. Molecular pathology behind partial/full EAE reversal was associated with differential GMF-ß-Ser-83 phosphorylation/GM-CSF expression levels in enteric glial cells owing to GMFBI.1 bioavailability. In addition, we observed leaky gut reversal, tight junction protein ZO-1 restoration, beneficial gut microbiome repopulation, recovery from gut dysbiosis, and upregulation of Treg cells. GMFBI.1's dual gut/brain targeting of GMF-ß has therapeutical/translational potential in controlling autoimmunity in MS.

Interactome based identification and validation of prefoldin 5-α for prognosing CNS leukemia in B-ALL patients.

We report here the identification and validation of prefoldin 5-alpha (PFDN5-α) for the first time as prognostic biomarker for prediction of central nervous system (CNS) leukemia of B cell acute lymphoblastic leukemia (B-ALL) origin. Since cerebrospinal fluid (CSF) cytology being the gold standard of diagnosis for CNS leukemia with poor sensitivity, mandatory prophylactic intrathecal chemotherapy is administered irrespective of patients develop CNS leukemia. Thus, using interactome studies, we identified PFDN5-α as a prognostic biomarker for predicting CNS leukemia by interacting lymphoblastic proteins and CSF from B-ALL patients using far-western clinical proteomics approach. Validation by both western and ELISA methods confirmed our results. For further clinical translation, we performed Receiver Operating Characteristic (ROC) curve analysis generated from CNS +ve (n = 25) and -ve (n = 40) CSF samples from B-ALL patients and identified PFDN5-α-CSF reactivity cut-off value as 0.456. Values below 0.456 indicate the patient is at risk of developing CNS leukemia and suggestive of having intrathecal chemotherapy. Further flow cytometry validation for CNS leukemia positivity revealed that with increasing blast cells, a decrease in PFDN5-α-CSF reactivity confirming ELISA based PFDN5α-CSF reactivity assay. Predicting CNS leukemia development risk by ELISA based PFDN5-α-CSF reactivity assay could have potential in the clinical management of CNS leukemia.

Nanotechnology Approaches for Enhanced CNS Drug Delivery in the Management of Schizophrenia.

Schizophrenia is a neuropsychiatric disorder mainly affecting the central nervous system (CNS), presented with auditory and visual hallucinations, delusion and withdrawal from society. Abnormal dopamine levels mainly characterise the disease; various theories of neurotransmitters explain the pathophysiology of the disease. The current therapeutic approach deals with the systemic administration of drugs other than the enteral route, altering the neurotransmitter levels within the brain and providing symptomatic relief. Fluid biomarkers help in the early detection of the disease, which would improve the therapeutic efficacy. However, the major challenge faced in CNS drug delivery is the blood-brain barrier (BBB). Nanotherapeutic approaches may overcome these limitations, which will improve safety, efficacy, and targeted drug delivery. This review article addresses the main challenges faced in CNS drug delivery and the significance of current therapeutic strategies and nanotherapeutic approaches for a better understanding and enhanced drug delivery to the brain, which improve the quality of life of schizophrenia patients.

Exploiting the preferential phagocytic uptake of nanoparticle-antigen conjugates for the effective treatment of autoimmunity.

Tolerance induction is central to the suppression of autoimmunity. Here, we engineered the preferential uptake of nano-conjugated autoantigens by spleen-resident macrophages to re-introduce self-tolerance and suppress autoimmunity. The brain autoantigen, myelin oligodendrocyte glycoprotein (MOG), was conjugated to 200 or 500 nm silica nanoparticles (SNP) and delivered to the spleen and liver-resident macrophages of experimental autoimmune encephalomyelitis (EAE) mice, used as a model of multiple sclerosis. MOG-SNP conjugates significantly reduced signs of EAE at a very low dose (50 µg) compared to the higher dose (>800 µg) of free-MOG. This was associated with reduced proliferation of splenocytes and pro-inflammatory cytokines secretion, decreased spinal cord inflammation, demyelination and axonal damage. Notably, biodegradable porous SNP showed an enhanced disease suppression assisted by elevated levels of regulatory T cells and programmed-death ligands (PD-L1/2) in splenic and lymph node cells. Our results demonstrate that targeting nano-conjugated autoantigens to tissue-resident macrophages in lymphoid organs can effectively suppress autoimmunity.

Manipulating Edge Current in Hexagonal Boron Nitride via Doping and Friction.

We map spatially correlated electrical current on the stacking boundaries of pristine and doped hexagonal boron nitride (hBN) to distinguish from its insulating bulk via conductive atomic force microscopy (CAFM). While the pristine edges of hBN show an insulating nature, the O-doped edges reveal a current 2 orders of higher even for bulk layers where the direct transmission through tunnel barrier is implausible. Instead, the nonlinear current-voltage characteristics (I-V) at the edges of O-doped hBN can be explained by trap-assisted lowering of the tunnel barrier by adopting a Poole-Frenkel (PF) model. However, in the stacked heterostructure with multilayer graphene (MLG) on top, the buried edge of pristine hBN shows a signature of electron conduction in the scanning mode which contradicts the first-principle calculation of spatial distribution of local density of states (LDOS) data. Enhancement of friction between the Pt-tip and MLG at the step-edge of the heterostructure while scanning in the contact mode has prompted us to construct a phenomenological model where the localization of opposite surface charges on two conducting plates (MLG and Si substrate) containing a dielectric film (hBN) with negatively charged defects creates an internal electric field opposite to the external electric field due to the applied voltage bias in the CAFM setup. An equivalent circuit with a parallel resistor network based on a vertical conducting channel through the MLG/hBN edge and an in-plane surface carrier transport through MLG can successfully analyze the current maps on pristine/doped hBN and the related heterostructures. These results yield fundamental insight into the emerging field of insulatronics in which defect-induced electron transport along the edge can be manipulated in an 1D-2D synergized insulator.

Adipose derived mesenchymal stem cell secretome formulation as a biotherapeutic to inhibit growth of drug resistant triple negative breast cancer.

In the present study, a protocol was developed for processing of human adipose derived mesenchymal stem cell secretome formulation of varying concentration. Its molecular composition was evaluated, and its effectiveness in vitro using breast cancer cell lines, and in vivo in a nude mice breast cancer model was studied to determine its role in suppressing triple negative breast cancer in a dose dependent manner. Because the secretome could have value as an add-on therapy along with a current drug, the effectiveness of the secretome both in monotherapy and in combination therapy along with paclitaxel was evaluated. The results showed significant cell kill when exposed to the secretome above 20 mg/ml at which concentration there was no toxicity to normal cells. 70 mg/ml of SF showed 90 ± 10% apoptosis and significant decrease in CD44+/CD24-, MDR1+ and PDL-1+ cancer cells. In vivo, the tumor showed no growth after daily intra tumor injections at 50 mg/ml and 100 mg/ml doses whereas substantial tumor growth occurred after saline intra tumor injection. The study concludes that SF is a potential biotherapeutic for breast cancer and could be used initially as an add-on therapy to other standard of care to provide improved efficacy without other adverse effects.

Intracranially injectable multi-siRNA nanomedicine for the inhibition of glioma stem cells.

BACKGROUND: Nanoparticle siRNA-conjugates are promising clinical therapeutics as indicated by recent US-FDA approval. In glioma stem cells (GSC), multiple stemness associated genes were found aberrant. We report intracranially injectable, multi-gene-targeted siRNA nanoparticle gel (NPG) for the combinatorial silencing of 3 aberrant genes, thus inhibiting the tumorogenic potential of GSCs. METHODS: NPG loaded with siRNAs targeted against FAK, NOTCH-1, and SOX-2 were prepared by the self-assembly of siRNAs with protamine-hyaluronic acid combination. Electron microscopy, DLS, and agarose gel electrophoresis were used for the physicochemical characterization. Cell transfection and gene-silencing efficiency were studied using human mesenchymal stem cells and rat C6 glioma-derived GSCs. Neurosphere inhibition was tested in vitro using GSCs derived from C6 cell line and glioma patient samples. Patient-derived xenograft model and orthotopic rat glioma model were used to test the effect of NPG on in vivo tumorigenicity. RESULTS: The siRNA nanoparticles with an average size ~ 250 nm and ~ 95% loading efficiency showed cellular uptake in ~95.5% GSCs. Simultaneous gene silencing of FAK, NOTCH-1, and SOX-2 led to the inhibition of neurosphere formation by GSCs, whereas normal stem cells remained unaffected and retained neuronal differentiation capability. GBM PDX models manifested significant impairment in the tumorigenic potential of NPG treated GSCs. Intracranial injection of NPG inhibited tumor growth in orthotopic rat brain tumor model. CONCLUSION: Intracranially injectable n-siRNA NPG targeted to multiple stem-cell signaling impairs glioma initiation capabilities of GSCs and inhibited tumor growth in vivo.

Significance of monitoring vascular endothelial growth factor, monocyte chemoattractant protein-1 and Interleukin-8 in diabetic macular edema towards early identification of nonresponders to ranibizumab therapy.

Purpose: Identification of nonresponders prior to anti-vascular endothelial growth factor (anti-VEGF) therapy would help in the judicious clinical management of diabetic macular edema (DME) patients. Thus, a systematic study was initiated to identify nonresponding DME patient population undergoing ranibizumab treatment to figure out additional inflammatory components that may contribute to their nonresponsiveness to anti-VEGF therapy. Methods: A total of 40 patients recruited to this investigator-initiated trial received intravitreal ranibizumab monthly for 3 months. The fourth- and fifth-month injections were according to PRN protocol and the sixth-month injection was mandatory. Best-corrected visual acuity (BCVA), central macular thickness (CMT), and VEGF in aqueous humor were measured for all the patients. Patients were grouped into responders/nonresponders on the formulated criteria and the levels of key pro-inflammatory cytokines were also measured between the two groups at baseline, 2 month and 5 months using cytometric bead array (CBA). Results: Eleven patients were categorized (29.72%) as responders and 10 patients (27.02%) as nonresponders. Nonresponders showed poorer BCVA (P = 0.024, 0.045, and 0.048 for 4, 5, and 6 months) and higher CMT (P = 0.021, 0.0008 and <0.0001 for baseline, 1, 2, 3, 4, 5, and 6 months) compared to responders. The cytokines IL-8, MCP-1 were significantly up regulated (P = 0.0048 and 0.029 for MCP-1 and IL-8) in nonresponders. Conclusion: Elevated MCP-1 and IL-8 levels found in the nonresponders could be used as a prognostic marker to identify these groups of patients and can help in developing alternative treatment options along with anti-VEGF therapy.

Role of Surface Termination in the Metal-Insulator Transition of V2O3(0001) Ultrathin Films.

Surface termination is known to play an important role in determining the physical properties of materials. It is crucial to know how surface termination affects the metal-insulator transition (MIT) of V2O3 films for both fundamental understanding and its applications. By changing growth parameters, we achieved a variety of surface terminations in V2O3 films that are characterized by low-energy electron diffraction (LEED) and photoemission spectroscopy techniques. Depending upon the terminations, our results show that MIT can be partially or fully suppressed near the surface region due to the different fillings of the electrons at the surface and subsurface layers and the change of screening length compared to the bulk. Across MIT, a strong redistribution of spectral weight and its transfer from a high-to-low-binding energy regime is observed in a wide energy scale. Our results show that the total spectral weight in the low-energy regime is not conserved across MIT, indicating a breakdown of the "sum rules of spectral weight", signature of a strongly correlated system. Such a change in spectral weight is possibly linked to the change in hybridization, lattice volume (i.e., effective carrier density), and the spin degree of freedom in the system that occurs across MIT. We find that MIT in this system is strongly correlation-driven, where the electron-electron interactions play a pivotal role. Moreover, our results provide better insight into the understanding of the electronic structure of strongly correlated systems and highlight the importance of accounting for surface effects during interpretation of the physical property data mainly using surface-sensitive probes, such as surface resistivity.

Substrate Specific Inhibitor Designed against the Immunomodulator GMF-beta Reversed the Experimental Autoimmune Encephalomyelitis.

The concept of substrate inhibition to prevent its phosphorylation has potential in drug discovery and is envisioned to treat the autoimmune disorder multiple sclerosis (MS). Glia maturation factor-ß (GMF-ß) Ser83 phosphorylation by protein kinase A (PKA) is pivotal in the activation of GMF-ß-p38MAPK-NFκB biochemical pathway towards proinflammatory response induction in experimental autoimmune encephalomyelitis (EAE). Using structure-based drug design, we identified the small molecule inhibitor 1-H-indazole-4yl methanol (GMFBI.1) that specifically blocked Ser83 phosphorylation site on GMF-ß substrate. Using in vitro and in vivo techniques, molecular mechanism of action of GMFBI.1's direct interaction with GMF-ß substrate and prevention of its Ser83 phosphorylation was established. GMFBI.1 down regulated p38MAPK phosphorylation and NFκB expression essential for proinflammatory response. Further, GMFBI.1 administration at peak of EAE reversed clinical symptoms, immunopathology, proinflammatory cytokine response and up regulated the anti-inflammatory cytokines. Present strategy of substrate inhibition against the key immunomodulatory target has immense therapeutic potential in MS.

Generation of humanized single-chain fragment variable immunotherapeutic against EGFR variant III using baculovirus expression system and in vitro validation.

Epidermal growth factor receptor variant III (EGFRvIII) is known to be specifically expressed in cancer cells and associated with tumor virulence. The receptor provides an opportunity for both specifically targeting the tumor cells as well as for potentially controlling and inhibiting tumor progression. In this study, humanized anti-EGFRvIII single-chain fragment variable (hscFv) was expressed in insect cell culture system to accommodate post-translational glycosylations crucial for the fragment stability and efficacy. Target specific binding of the developed fragment to EGFRvIII expressing cell lines and EGFRvIII positive glioblastoma patient samples was evaluated by immunocytochemistry and immunohistochemistry respectively. Downstream intracellular signaling mechanisms related to the action of the developed antibody fragment on growth/metabolism of the cell was evaluated in U87-EGFRvIII human glioblastoma cell lines. It was observed that the hscFv bound specifically to EGFRvIII in mutant expressing cells. Functionally, hscFv was found to confer anti-proliferative properties in EGFRvIII expressing cell lines by downregulating phosphorylation of EGFR/EGFRvIII, Lyn, PI3K and GLUT3 involved in proliferation and metabolism. This study demonstrated the significance of hscFv as a potential immunotherapeutic agent as well as a targeting agent for specific delivery of drugs to EGFRvIII expressing cancer cells.

Fibronectin protein expression in renal cell carcinoma in correlation with clinical stage of tumour.

BACKGROUND: Carcinogenesis is a multistep process which involves interplay between the tumour cells and the matrix proteins. This occurs by adherence between the tumour cells and proteins in the extracellular matrix. VHL mutation affects through the hypoxia inducible factor (HIF) and causes changes in various tissue proteins like VEGF, PDGF, TGF, Fibronectin and others. As not much literature is available, we aim to quantify the changes of fibronectin protein in renal cell carcinoma (RCC) tissue. METHODS: This Prospective unbalanced case control study was conducted over a period of 18 months from April 2016 to September 2017. The patients undergoing nephrectomy for the diagnosis of RCC were included in the study after obtaining written informed consent. Patients were excluded from study, if normal renal tissue could not be identified in the resected kidney and if the artery clamp time to retrieval of tissue was more than 30 min. Fibronectin protein is estimated in the tumour tissue by gel electrophoresis and western blotting which is compared with that of normal kidney tissue of the same kidney. Results have been expressed as absolute values with standard deviation and relative expression (RE). RESULTS: Of the 21 patients analysed 15 showed an increase in fibronectin expression in the renal tumour tissue while 6 did not. The mean expression of Fibronectin protein has increased 1.5 times in the tumour tissue when compared with the normal tissue. The increase was 1.54 times in early tumours compared to 1.37 times in advanced tumours of RCC. CONCLUSIONS: Fibronectin showed a 1.5 times increase in the tumour compared to normal. This increase is more in Stage 1&2 tumours when compared to the Stage 3&4 tumours.

Identification of prolargin expression in articular cartilage and its significance in rheumatoid arthritis pathology.

Qualitative 2D gel-electrophoresis (2DE) protein profiling for osteoarthritis (OA) and rheumatoid arthritis (RA) is challenging because of selective protein loss due to discrepancies in protein precipitation methodologies. Thus, we aimed at developing qualitative protein representation from OA/RA articular cartilage without protein precipitation towards identification of clinically relevant proteins. Chondroitinase digested human articular cartilages from RA patients were subjected to protein extraction using guanidinium hydrochloride (GuHCl) or 8 M urea with 10 or 2% ASB-14-4 or 0.45 M urea with 2% ASB-14-4 with cetylpyridinium chloride (CPC). The GuHCl extract is further protein precipitated with acetone or ammonium acetate-methanol or centricon-fractionated using 100 kDa cut filters and protein precipitated using ethanol. Processed extracts were subjected to 2DE to identify protein profiles. Poor proteins representations were observed in 2D gels with protein precipitated samples compared to qualitative protein representations seen in 2D gels of 0.45 M urea and 2%ASB-14-4 extraction procedure reproducibly. The strategy circumventing protein precipitation generated qualitative 2D gels. RA vs OA gel comparison showed elevated prolargin levels in RA with biglycan levels remaining unaltered. Up regulation of prolargin in RA suggests the likelihood of an adaptive mechanism to control the increased osteoclastogenesis in RA and may have therapeutic value in controlling the disease.

Expression and Purification of Quinine Dihydro Pteridine Reductase from astrocytes and its significance in the astrocyte pathology.

Quinine dihydropteridinereductase (QDPR) is involved in the synthesis of tetradihydrobiopteridine (BH4) that serve as cofactor for many aromatic hydroxylases including induced nitric oxide synthase (NOS) leading to NO production. Increased activity of QDPR has been associated with decrease levels of TGF-ß, a cytokine that regulates the immune response and that elevated levels of NO has been associated with neurodegenerative diseases. Thus, expression of QDPR in astrocytes is essential to study the pathological changes observed in many neurodegenerative disorders. We have expressed QDPR in astrocytes and generated stably expressing clones that overexpresses QDPR. We further verified the specificity of QDPR expression using immunofluorescence and immunoblotting. To further confirm, we purified QDPR using Ni-NTA column and subjected the purified fraction to immunoblotting using anti-QDPR antibody and identified two major protein products of QDPR resolving at 25 and 17 kDa as reported in the literature. In order to further assess the significance of QDPR expression, we verified the expression of iNOS in QDPR over expressing cells. We show for the first time statistically significant up regulation of iNOS in QDPR overexpressing astrocytes. Increased expression of iNOS associated with astrocyte pathology seen in many neurodegenerative disorders may have implications in autoimmune neurodegenerative disorders.

Recombinant expression of extracellular domain of mutant Epidermal Growth Factor Receptor in prokaryotic and baculovirus expression systems.

Epidermal Growth Factor Receptor variant III (EGFRvIII) is a tumor specific antigen detected in various tumors including gliomas, breast cancer, lung cancer, head and neck squamous cell carcinoma (HNSCC). Screening of EGFRvIII targeting drug molecules can be accelerated by developing drug screening platforms using recombinantly expressed protein. Choice of expression system is one of the major factors deciding the success of recombinant expression of a protein. In our study, we have tried to express and purify the extracellular domain (ECD) of this highly unstable protein using bacterial and baculovirus expression systems to select the expression system suited for our purpose. Even though the protein was successfully expressed in prokaryotic system, purification could be done only under denaturing conditions. But in the baculovirus expression system, the protein was expressed in soluble form and could be purified under native conditions, with single step of purification. Based on our results, we conclude that insect cells are better choice over E. coli cells for expressing EGFRvIII ECD in soluble form. This study provides insights for other researchers involved in expression of similar unstable membrane proteins, on selecting the best expression system and challenges involved.

Significance of elevated Prohibitin 1 levels in Multiple Sclerosis patients lymphocytes towards the assessment of subclinical disease activity and its role in the central nervous system pathology of disease.

Multiple Sclerosis (MS) is an autoimmune-neurodegenerative disorder managed therapeutically by modulating lymphocytes activity which has potential in disease management. Prohibitin 1(PHB) that controls the reactive oxygen species (ROS) and present on the activated lymphocytes have significance in the therapy of MS as esters of fumaric acid that regulates ROS is in phase II/III clinical trials. Thus, we evaluated the expression levels of PHB1 in experimental autoimmune encephalomyelitis (EAE), the animal model of MS and on MS patient's lymphocytes. PHB levels in brain tissue of EAE animals were determined by immunoblotting and on blood lymphocytes from MS relapse, Remission, Optic Neuritis, Neurological controls and Healthy volunteers by FACS using anti-PHB and anti-CD45 antibodies. We observed significant elevation of PHB in EAE brains (91.0 ±â€¯17.59%) vs controls (29.8 ±â€¯12.9%) (p = 0.01) and on lymphocytes of MS patients in acute (73.5 ±â€¯11.20%) or relapsing (69.3 ±â€¯17.33%) phase compared to remission (45.9 ±â€¯8.08%) [p = 0.034 acute vs remission; p = 0.004 relapse vs remission]. Up regulation of PHB in relapsing vs remission MS patients imply the potential use of PHB to clinically evaluate subclinical disease status towards prognosis of an oncoming relapse. Elevated PHB levels in EAE brains signify the role of PHB in regulating ROS and implies PHB's role in oxidative stress.

Development and molecular characterization of polymeric micro-nanofibrous scaffold of a defined 3-D niche for in vitro chemosensitivity analysis against acute myeloid leukemia cells.

Standard in vitro drug testing employs 2-D tissue culture plate systems to test anti-leukemic drugs against cell adhesion-mediated drug-resistant leukemic cells that harbor in 3-D bone marrow microenvironments. This drawback necessitates the fabrication of 3-D scaffolds that have cell adhesion-mediated drug-resistant properties similar to in vivo niches. We therefore aimed at exploiting the known property of polyurethane (PU)/poly-L-lactic acid (PLLA) in forming a micro-nanofibrous structure to fabricate unique, not presented before, as far as we are aware, 3-D micro-nanofibrous scaffold composites using a thermally induced phase separation technique. Among the different combinations of PU/PLLA composites generated, the unique PU/PLLA 60:40 composite displayed micro-nanofibrous morphology similar to decellularized bone marrow with increased protein and fibronectin adsorption. Culturing of acute myeloid leukemia (AML) KG1a cells in FN-coated PU/PLLA 60:40 shows increased cell adhesion and cell adhesion-mediated drug resistance to the drugs cytarabine and daunorubicin without changing the original CD34(+)/CD38(-)/CD33(-) phenotype for 168 hours compared to fibronectin tissue culture plate systems. Molecularly, as seen in vivo, increased chemoresistance is associated with the upregulation of anti-apoptotic Bcl2 and the cell cycle regulatory protein p27(Kip1) leading to cell growth arrest. Abrogation of Bcl2 activity by the Bcl2-specific inhibitor ABT 737 led to cell death in the presence of both cytarabine and daunorubicin, demonstrating that the cell adhesion-mediated drug resistance induced by Bcl2 and p27(Kip1) in the scaffold was similar to that seen in vivo. These results thus show the utility of a platform technology, wherein drug testing can be performed before administering to patients without the necessity for stromal cells.