Raja Shekar Rachakatla

Human umbilical cord matrix stem cells : Preliminary characterization and effect of transplantation in a rodent model of parkinson's disease

The umbilical cord contains an inexhaustible, noncontroversial source of stem cells for therapy. In the U.S., stem cells found in the umbilical cord are routinely placed into bio‐hazardous waste after birth. Here, stem cells derived from human umbilical cord Whartons Jelly, called umbilical cord matrix stem (UCMS) cells, are characterized. UCMS cells have several properties that make them of interest as a source of cells for therapeutic use. For example, they 1) can be isolated in large numbers, 2) are negative for CD34 and CD45, 3) grow robustly and can be frozen/thawed, 4) can be clonally expanded, and 5) can easily be engineered to express exogenous proteins. UCMS cells have genetic and surface markers of mesenchymal stem cells (positive for CD10, CD13, CD29, CD44, and CD90 and negative for CD14, CD33, CD56, CD31, CD34, CD45, and HLA‐DR) and appear to be stable in terms of their surface marker expression in early passage (passages 4–8). Unlike traditional mesenchymal stem cells derived from adult bone marrow stromal cells, small populations of UCMS cells express endoglin (SH2, CD105) and CD49e at passage 8. UCMS cells express growth factors and angiogenic factors, suggesting that they may be used to treat neurodegenerative disease. To test the therapeutic value of UCMS cells, undifferentiated human UCMS cells were transplanted into the brains of hemiparkinsonian rats that were not immune‐suppressed. UCMS cells ameliorated apomorphine‐induced rotations in the pilot test. UCMS cells transplanted into normal rats did not produce brain tumors, rotational behavior, or a frank host immune rejection response. In summary, the umbilical cord matrix appears to be a rich, noncontroversial, and inexhaustible source of primitive mesenchymal stem cells.

A/C magnetic hyperthermia of melanoma mediated by iron(0)/iron oxide core/shell magnetic nanoparticles: a mouse study

BackgroundThere is renewed interest in magnetic hyperthermia as a treatment modality for cancer, especially when it is combined with other more traditional therapeutic approaches, such as the co-delivery of anticancer drugs or photodynamic therapy.MethodsThe influence of bimagnetic nanoparticles (MNPs) combined with short external alternating magnetic field (AMF) exposure on the growth of subcutaneous mouse melanomas (B16-F10) was evaluated. Bimagnetic Fe/Fe3O4 core/shell nanoparticles were designed for cancer targeting after intratumoral or intravenous administration. Their inorganic center was protected against rapid biocorrosion by organic dopamine-oligoethylene glycol ligands. TCPP (4-tetracarboxyphenyl porphyrin) units were attached to the dopamine-oligoethylene glycol ligands.ResultsThe magnetic hyperthermia results obtained after intratumoral injection indicated that micromolar concentrations of iron given within the modified core-shell Fe/Fe3O4 nanoparticles caused a significant anti-tumor effect on murine B16-F10 melanoma with three short 10-minute AMF exposures. We also observed a decrease in tumor size after intravenous administration of the MNPs followed by three consecutive days of AMF exposure 24 hrs after the MNPs injection.ConclusionsThese results indicate that intratumoral administration of surface modified MNPs can attenuate mouse melanoma after AMF exposure. Moreover, we have found that after intravenous administration of micromolar concentrations, these MNPs are capable of causing an anti-tumor effect in a mouse melanoma model after only a short AMF exposure time. This is a clear improvement to state of the art.

Development of human umbilical cord matrix stem cell-based gene therapy for experimental lung tumors

Umbilical cord matrix stem (UCMS) cells are unique stem cells derived from Whartons jelly, which have been shown to express genes characteristic of primitive stem cells. To test the safety of these cells, human UCMS cells were injected both intravenously and subcutaneously in large numbers into severe combined immunodeficiency (SCID) mice and multiple tissues were examined for evidence of tumor formation. UCMS cells did not form gross or histological teratomas up to 50 days posttransplantation. Next, to evaluate whether UCMS cells could selectively engraft in xenotransplanted tumors, MDA 231 cells were intravenously transplanted into SCID mice, followed by intravenous transplantation of UCMS cells 1 and 2 weeks later. UCMS cells were found near or within lung tumors but not in other tissues. Finally, UCMS cells were engineered to express human interferon beta – designated ‘UCMS−IFN-β’. UCMS−IFN-β cells were intravenously transplanted at multiple intervals into SCID mice bearing MDA 231 tumors and their effect on tumors was examined. UCMS−IFN-β cells significantly reduced MDA 231 tumor burden in SCID mouse lungs indicated by wet weight. These results clearly indicate safety and usability of UCMS cells in cancer gene therapy. Thus, UCMS cells can potentially be used for targeted delivery of cancer therapeutics.

Naive human umbilical cord matrix derived stem cells significantly attenuate growth of human breast cancer cells in vitro and in vivo.

The effect of un-engineered (naïve) human umbilical cord matrix stem cells (hUCMSC) on the metastatic growth of MDA 231 xenografts in SCID mouse lung was examined. Three weekly IV injections of 5x10(5) hUCMSC significantly attenuated MDA 231 tumor growth as compared to the saline-injected control. IV injected hUCMSC were detected only within tumors or in close proximity to the tumors. This in vivo result was corroborated by multiple in vitro studies such as colony assay in soft agar and [(3)H]-thymidine uptake. These results suggest that naïve hUCMSC may be a useful tool for cancer cytotherapy.

Attenuation of Mouse Melanoma by A/C Magnetic Field after Delivery of Bi-Magnetic Nanoparticles by Neural Progenitor Cells

Localized magnetic hyperthermia as a treatment modality for cancer has generated renewed interest, particularly if it can be targeted to the tumor site. We examined whether tumor-tropic neural progenitor cells (NPCs) could be utilized as cell delivery vehicles for achieving preferential accumulation of core/shell iron/iron oxide magnetic nanoparticles (MNPs) within a mouse model of melanoma. We developed aminosiloxane-porphyrin functionalized MNPs, evaluated cell viability and loading efficiency, and transplanted neural progenitor cells loaded with this cargo into mice with melanoma. NPCs were efficiently loaded with core/shell Fe/Fe(3)O(4) MNPs with minimal cytotoxicity; the MNPs accumulated as aggregates in the cytosol. The NPCs loaded with MNPs could travel to subcutaneous melanomas, and after A/C (alternating current) magnetic field (AMF) exposure, the targeted delivery of MNPs by the cells resulted in a measurable regression of the tumors. The tumor attenuation was significant (p < 0.05) a short time (24 h) after the last of three AMF exposures.

Combination Treatment of Human Umbilical Cord Matrix Stem Cell-Based Interferon-Beta Gene Therapy and 5-Fluorouracil Significantly Reduces Growth of Metastatic Human Breast Cancer in SCID Mouse Lungs

Umbilical cord matrix stem (UCMS) cells that were engineered to express interferon-beta (IFN-β) were transplanted weekly for three weeks into MDA 231 breast cancer xenografts bearing SCID mice in combination with 5-fluorouracil (5-FU). The UCMS cells were found within lung tumors but not in other tissues. Although both treatments significantly reduced MDA 231 tumor area in the SCID mouse lungs, the combined treatment resulted in a greater reduction in tumor area than by either treatment used alone. These results indicate that a combination treatment of UCMS-IFN-β cells and 5-FU is a potentially effective therapeutic procedure for breast cancer.

Human umbilical cord matrix-derived stem cells expressing interferon-β gene significantly attenuate bronchioloalveolar carcinoma xenografts in SCID mice

Mesenchymal stem cells derived from the human umbilical cord matrix (hUCMSCs) have great potential for therapeutic use for multiple diseases. The strategy that uses therapeutic gene-transfected hUCMSCs as cellular vehicles for targeted biologic agent delivery has solved the problem of short half-life or excessive toxicity of biological agent(s) in vivo. Interferon-beta (IFN-beta) has demonstrated a potent antitumor effect on many types of cancer cell lines in vivo. The aim of this study was to determine the anti-cancer effect of IFN-beta gene-transfected hUCMSCs (IFN-beta-hUCMSCs) on cells derived from bronchioloalveolar carcinoma, a subset of lung adenocarcinoma that is difficult to treat. The co-culture of a small number of IFN-beta-hUCMSCs with the human bronchioloalveolar carcinoma cell lines H358 or SW1573 significantly inhibited growth of both types of carcinoma cell lines. The culture medium conditioned by these cells also significantly attenuated the growth of both carcinoma cells, but this attenuation was abolished by adding anti-IFN-beta antibody. Finally, systemic administration of IFN-beta-hUCMSCs through the tail vein markedly attenuated growth of orthotopic H358 bronchioloalveolar carcinoma xenografts in SCID mice by increasing apoptosis. These results clearly indicate that IFN-beta-hUCMSCs caused cell death of bronchioloalveolar carcinoma cells through IFN-beta production, thereby attenuating tumor growth in vivo. These results indicate that IFN-beta-hUCMSCs are a powerful anti-cancer cytotherapeutic tool for bronchioloalveolar carcinoma.

Non-random tissue distribution of human naïve umbilical cord matrix stem cells

AIM To determine the tissue and temporal distribution of human umbilical cord matrix stem (hUCMS) cells in severe combined immunodeficiency (SCID) mice. METHODS For studying the localization of hUCMS cells, tritiated thymidine-labeled hUCMS cells were injected in SCID mice and tissue distribution was quantitatively determined using a liquid scintillation counter at days 1, 3, 7 and 14. Furthermore, an immunofluorescence detection technique was employed in which anti-human mitochondrial antibody was used to identify hUCMS cells in mouse tissues. In order to visualize the distribution of transplanted hUCMS cells in H&E stained tissue sections, India Black ink 4415 was used to label the hUCMS cells. RESULTS When tritiated thymidine-labeled hUCMS cells were injected systemically (iv) in female SCID mice, the lung was the major site of accumulation at 24 h after transplantation. With time, the cells migrated to other tissues, and on day three, the spleen, stomach, and small and large intestines were the major accumulation sites. On day seven, a relatively large amount of radioactivity was detected in the adrenal gland, uterus, spleen, lung, and digestive tract. In addition, labeled cells had crossed the blood brain barrier by day 1. CONCLUSION These results indicate that peripherally injected hUCMS cells distribute quantitatively in a tissue-specific manner throughout the body.

Wharton's jelly stromal cells as potential delivery vehicles for cancer therapeutics

There is now compelling evidence that stem cells can be used as gene therapy delivery cells. Stem cells isolated from the Whartons jelly of the umbilical cord (termed Whartons jelly stromal cells) can be harvested noninvasively in large numbers and have been shown to traffic to tumors but do not form tumors themselves. WJS cells have low immunogenicity and they have also been engineered to secrete a cytokine, shown to home locally into the tumors in mice and with subsequent tumor attenuation. Naive rat and human Whartons jelly stromal cells that are not engineered to secrete an exogenous protein also exert a potent anticancer effect in preclinical models.

In vitro Effects of Canine WhartonâÂÂs Jelly Mesenchymal Stromal Cells and Micellar Nanoparticles on Canine Osteosarcoma D17 Cell Viability

Objectives: To isolate and maintain canine Wharton’s jelly mesenchymal stromal cells (WJMSC) in culture, determine the effects of micellar nanoparticles containing doxorubicin (DOX) on WJMSC and canine osteosarcoma (OSA) D17 cells, and determine the effects of WJMSC loaded with micellar nanoparticles containing DOX on OSA D17 cell viability. Procedures: Stromal cells were isolated from canine umbilical cords. Micellar nanoparticles containing DOX were prepared and added to individual culture plates containing canine WJMSC and OSA D17 cells to determine DOX in micelles (DOX-M) effects on cell growth and viability. Conditioned media (CM) from culture plates containing canine WJMSC incubated with various DOX-M concentrations was added to OSA D17 cells. An MTT assay was performed to assess osteosarcoma D17 cell viability. A trypan blue stain was utilized to perform cell counts to determine the effect of the DOX-M on WJMSC growth. Results: WJMSC were successfully isolated and maintained in culture. Micellar nanoparticles containing DOX decreased viability of OSA D17 cells. Osteosarcoma D17 cell viability decreased following incubation with CM obtained from WJMSC loaded with DOX-M. Significant decreases in OSA D17 cell viability were observed after incubation with the CM of canine WJMSC loaded with 10 μM DOX-M at 96 hours (p=0.0037). Significant decreases were also observed with the CM from WJMSC loaded with 1 μM DOX-M at 96 hours (p=0.0222). WJMSC numbers decreased in a dose dependent manner following incubation with DOX-M. The decrease in WJMSC number was not secondary to cytotoxicity as all variables produced similar percentages of dead WJMSC. Conclusions: Canine WJMSC can be isolated and maintained in culture. DOX-M produces OSA D17 cytotoxicity and slows proliferation of canine WJMSC. WJMSC containing DOX-M cause OSA D17 cell cytotoxicity. These data support in vivo experiments utilizing canine WJMSC and micellar nanoparticles.