Quantitative analysis of cell tracing by in vivo imaging system

Non-Invasive Luciferase Imaging of Type I Interferon Induction in a Transgenic Mouse Model of Biomaterial Associated Bacterial Infections: Microbial Specificity and Inter-Bacterial Species Interactions

The performance of biomaterials is often compromised by bacterial infections and subsequent inflammation. So far, the conventional analysis of inflammatory processes in vivo involves time-consuming histology and biochemical assays. The present study employed a mouse model where interferon beta (IFN-β) is monitored as a marker for non-invasive rapid detection of inflammation in implant-related infections. The mouse model comprises subcutaneous implantation of morphologically modified titanium, followed by experimental infections with four taxonomically diverse oral bacteria: Streptococcus oralis, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Treponema denticola (as mono culture or selected mixed-culture). IFN-β expression increased upon infections depending on the type of pathogen and was prolonged by the presence of the implant. IFN-β expression kinetics reduced with two mixed species infections when compared with the single species. Histological and confocal microscopy confirmed pathogen-specific infiltration of inflammatory cells at the implant-tissue interface. This was observed mainly in the vicinity of infected implants and was, in contrast to interferon expression, higher in infections with dual species. In summary, this non-invasive mouse model can be used to quantify longitudinally host inflammation in real time and suggests that the polymicrobial character of infection, highly relevant to clinical situations, has complex effects on host immunity.

Genetically re-engineered K562 cells significantly expand and functionally activate cord blood natural killer cells: Potential for adoptive cellular immunotherapy

Natural killer (NK) cells play a significant role in reducing relapse in patients with hematological malignancies after allogeneic stem cell transplantation, but NK cell number and naturally occurring inhibitory signals limit their capability. Interleukin-15 (IL-15) and 4-1BBL are important modulators of NK expansion and functional activation. To overcome these limitations, cord blood mononuclear cells (CB MNCs) were ex vivo expanded for 7 days with genetically modified K562-mbIL15-41BBL (MODK562) or wild-type K562 (WTK562). NK cell expansion; expression of lysosome-associated membrane protein-1 (LAMP-1), granzyme B, and perforin; and in vitro and in vivo cytotoxicity against B-cell non-Hodgkin lymphoma (B-NHL) were evaluated. In vivo tumor growth in B-NHL-xenografted nonobese diabetic severe combined immune deficient (NOD-scid) gamma (NSG) mice was monitored by tumor volume, cell number, and survival. CB MNCs cultured with MODK562 compared with WTK562 demonstrated significantly increased NK expansion (thirty-fivefold, p < 0.05); LAMP-1 (p < 0.05), granzyme B, and perforin expression (p < 0.001); and in vitro cytotoxicity against B-NHL (p < 0.01). Xenografted mice treated with MODK562 CB experienced significantly decreased B-NHL tumor volume (p = 0.0086) and B-NHL cell numbers (p < 0.01) at 5 weeks and significantly increased survival (p < 0.001) at 10 weeks compared with WTK562. In summary, MODK562 significantly enhanced CB NK expansion and cytotoxicity, enhanced survival in a human Burkitt's lymphoma xenograft NSG model, and could be used in the future as adoptive cellular immunotherapy after umbilical CB transplantation. Future directions include expanding anti-CD20 chimeric receptor-modified CB NK cells to enhance B-NHL targeting in vitro and in vivo.

Targeting CD20+ Aggressive B-cell Non-Hodgkin Lymphoma by Anti-CD20 CAR mRNA-Modified Expanded Natural Killer Cells In Vitro and in NSG Mice

The prognosis is very dismal for patients with relapsed CD20(+) B-cell non-Hodgkin lymphoma (B-NHL). Facilitating the development of alternative novel therapeutic strategies is required to improve outcomes in patients with recurrent/refractory CD20(+) B-NHL. In this study, we investigated functional activities of anti-CD20 CAR-modified, expanded peripheral blood NK cells (exPBNK) following mRNA nucleofection against CD20(+) B-NHL in vitro and in vivo. CAR(+) exPBNK had significantly enhanced in vitro cytotoxicity, compared with CAR(-) exPBNK against CD20(+) Ramos (P < 0.05), Daudi, Raji, and two rituximab-resistant cell lines, Raji-2R and Raji-4RH (P < 0.001). As expected, there was no significant difference against CD20(-) RS4;11 and Jurkat cells. CD107a degranulation and intracellular IFNγ production were also enhanced in CAR(+) exPBNK in response to CD20(+) B-NHL -: specific stimulation. In Raji-Luc and Raji-2R-Luc xenografted NOD/SCID/γ-chain(-/-) (NSG) mice, the luciferase signals measured in the CAR(+) exPBNK-treated group were significantly reduced, compared with the signals measured in the untreated mice and in mice treated with the CAR(-) exPBNK. Furthermore, the CAR exPBNK-treated mice had significantly extended survival time (P < 0.001) and reduced tumor size, compared with those of the untreated and the CAR(-) exPBNK-treated mice (P < 0.05). These preclinical data suggest that ex vivo-exPBNK modified with anti-CD20 CAR may have therapeutic potential for treating patients with poor-risk CD20(+) hematologic malignancies.

Establishment of animal models with orthotopic hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most serious health problems worldwide. Many researchers have investigated HCC at the level of genes, ribonucleic acid, proteins, cells, and animals. The resultant development of animal models and monitoring methods has improved the effectiveness of guidelines provided to researchers working with preclinical HCC models. HCC in animal models and clinical patients is monitored by various current imaging modalities such as ultrasound (US) imaging, computed tomography (CT), magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT), positron emission tomography (PET) and bioluminescence imaging (BLI). These techniques are currently used for both preclinical and clinical assessment, and provide valuable diagnostic information. In this article, we have mainly reviewed the established animal models and the assessment of orthotopic HCC using imaging modalities. Additionally, we have introduced a method of orthotopic HCC rat model developed in our laboratory. We have furthermore evaluated the occurrence of tumor mass using molecular imaging techniques.