CD4(+)CD25(+) T cells are potent immunoregulatory cells that suppress TCR-induced proliferation of CD4 and CD8 T cells in vitro by a cell contact-dependent mechanism. Addition of IL-2 or anti-CD28 abrogates CD4(+)CD25(+)-mediated suppression of proliferation and has been assumed to "break suppression." We examined IL-2 mRNA by quantitative PCR in cocultures of mouse CD4(+)CD25(+) and CD4(+)CD25...

Stable Mycobacterium avium infections of several Acanthamoeba strains were characterized by increased infection resistance of recent environmental isolates and reduced infectivity in the presence of other bacteria. Exposure of M. avium in coculture with Acanthamoeba castellanii to monochloramine yielded inactivation kinetics markedly similar to those observed for A. castellanii alone.

Vascular endothelial cells play a pivotal role in regulating leucocyte recruitment during inflammation, and their responses can be modulated by their local environment, including cells of the tissue stroma. We have developed a model system to examine how the communication between endothelial cells and fibroblasts regulates the recruitment of leucocytes and their subsequent subendothelial fate. ...

We examined how traditional farmers preserve the genetic diversity of a local common carp (Cyprinus carpio), which is locally referred to as "paddy field carp" (PF-carp), in a "globally important agricultural heritage system" (GIAHS), i.e., the 1,200-y-old rice-fish coculture system in Zhejiang Province, China. Our molecular and morphological analysis showed that the PF-carp has changed into a ...

Flat, two-dimensional (2D) cell culture substrates are simple to use but offer little control over cell morphologies and behavior. In this article, we present a number of novel and unique methods for advanced cell culture in microwells utilizing air bubbles as a way to seed cells in order to provide substantial control over cellular microenvironments and organization to achieve specific cell-ba...

In native tissues, different cell types are organized into defined structures and architectures that are critical for correct tissue function. In vitro cellular patterning methods enable control over the spatial organization of cells, permitting, to some extent, the reproduction of native tissue structures and the generation of a more "in vivo-like" culture platform. While this is advantageous ...

The effects of dermal fibroblasts on keratinocyte outgrowth on collagen substrata was studied using an in vitro keratinocyte-collagen gel composite model. Skin fibroblasts were seeded inside collagen gels, which remained attached to the cell culture plastic substratum. Fibroblasts incorporated in collagen gels were either kept viable throughout the study, or were lysed hypotonically with water ...

Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) have been shown as the most potential stem cell source for articular cartilage repair. In this study, we aimed to develop a method for long-term coculture of human articular chondrocytes (hACs) and hUCB-MSCs at low density in vitro to determine if the low density of hACs could enhance the hUCB-MSC chondrogenic differentiation...

When neighboring cells in the developing Drosophila wing express different levels of the transcription factor, dMyc, competitive interactions can occur. Cells with more dMyc proliferate and ultimately overpopulate the wing, whereas cells with less dMyc die, thereby preventing wing overgrowth. How cells sense dMyc activity differences between themselves and the nature of the process leading to c...