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Biology subjects

Sood, R.

Publications and source records attributed to Sood, R..

3 recordsLinked to original sources

Tissue architectural cues drive the emergence of non-random trafficking of human tumor cells in the larval zebrafish

Sites of metastasis are non-random, with certain types of cancers showing organ preference during distal colonization. Using multiple brain- and bone marrow-seeking human and murine breast cancer subclones, we determined that tumor cells that home to specific murine organs (brain and bone marrow) ultimately colonized analogous tissues (brain and caudal vein plexus [CVP]) in larval zebrafish. We then exploited the zebrafish model to delineate factors leading to differential cell homing and extravasation. Bone marrow-tropic clones showed higher expression of integrins and focal adhesions associated with mechanosensing machinery than brain-tropic clones and were more sensitive to vessel topography during extravasation. Knockdown of {beta}1 integrin reduced extravasation and redistributed organ targeting from disordered vessels in the CVP to the brain. Our results show that organ selectivity is driven by topography- and cell type-dependent extravasation at the tumor-endothelial interface in the larval zebrafish and provide important insights into the early stages of metastasis.

biophysics

Human macrophages survive and adopt activated genotypes in living zebrafish

The inflammatory response, modulated both by tissue resident macrophages and recruited monocytes from peripheral blood, plays a critical role in human diseases such as cancer and neurodegenerative disorders. Here, we sought a model to interrogate human immune behavior in vivo. We determined that primary human monocytes and macrophages survive in zebrafish for up to two weeks. Flow cytometry revealed that human monocytes cultured at the physiological temperature of the zebrafish survive and differentiate comparable to cohorts cultured at human physiological temperature. Moreover, key genes that encode for proteins that play a role in tissue remodeling were also expressed. Human cells migrated within multiple tissues at speeds comparable to zebrafish macrophages. Analysis of gene expression of in vivo educated human macrophages confirmed expression of activated macrophage phenotypes. Here, human cells adopted phenotypes relevant to cancer progression, suggesting that we can define the real time immune modulation of human tumor cells during the establishment of a metastatic lesion in zebrafish.

developmental biology

Highly-efficient Cpf1-mediated gene targeting in mice following high concentration pronuclear injection

Cpf1 has emerged as an alternative to the Cas9 RNA-guided nuclease. Here we show that gene targeting rates in mice using Cpf1 can meet or even surpass Cas9 targeting rates (approaching 100% targeting) but require higher concentrations of mRNA and guide. We also demonstrate that co-injecting two guides with close targeting sites can result in synergistic genomic cutting, even if one of the guides has minimal cutting activity.

genetics