The quality of cell culture media is critical for maintaining integrity of cells in culture and consistency between experiments. At Lifeline®, we have highly stringent quality control processes to ensure your experiments can be efficiently reproduced. We offer media that is optimized for growth of many tissue and cell types and also have media kits available to maintain undifferentiated stem cells, or induce stem cell differentiation into multiple lineages.

Certain components in media or serum can alter the identity of cells or signaling pathways.  For example:

• Phenol red can weakly activate the estrogen receptor, complicating experiments investigating hormone signaling pathways. Our media is phenol red-free (except for RPMI), making it the best choice for reproductive cell types.

In addition, our media can be used to culture primary cells isolated from mouse and human tissues. The studies described below investigate cell signaling using Lifeline® medium to culture mouse endothelial cells and human immune cells. The first two groups use VascuLife® endothelial culture medium to maintain mouse lung and/or cardiac endothelial cells in culture. The third study investigates the differentiation of human peripheral blood mononuclear cells into fibrocytes grown in vitro in FibroLife® fibroblast culture medium.

Studies using Lifeline® Medium to Culture Mouse and Human Primary Cells

Endothelial cells are the first line of defense against circulating bacteria. In a 2012 study, Reddy et al. investigated the role of peroxisome-activated receptor g (PPARg) on inflammatory responses in mouse lung endothelial cells. They found that following treatment with lipopolysaccharide (LPS), the immune-stimulating component of bacterial cell membranes, mice lacking PPARg displayed increased inflammation, edema, reactive oxygen species, and expression of the pro-inflammatory cytokines IL-6 and TNF-a. Furthermore, LPS signaling was upregulated in PPARg^-/- mice, suggesting that PPARg normally plays a role in suppressing LPS signaling.

To study these pathways further, the researchers isolated lung endothelial cells from wild-type and PPARg^-/- mice and sustained them in culture using Lifeline® VascuLife® medium. They found that, similar to the in vivo response, mouse lung endothelial cells lacking PPARg had an increased LPS-induced response. Together, the results of this study demonstrate that PPARg is a key suppressor of the LPS-induced inflammatory response.

Low oxygen conditions, called hypoxia, induce expression of hypoxia-inducible factors 1 and 2 (HIF-1 and -2), which activate the formation of new blood vessels, a process known as angiogenesis. HIF proteins have a and b subunits that form an active heterodimer when oxygen is low. In a 2012 study, Han et al. set out to define how loss of the HIF b subunit (ARNT) affected endothelial cell responses to hypoxia. Using aortic ring fragments from mice carrying a conditional allele of Arnt (Arnt^loxP/loxP), the researchers demonstrated that upon loss of Arnt (engineered following treatment with adenoviral Cre recombinase [Adeno-Cre]) vessels did not display hypoxia-induced growth.

To further evaluate this loss of response to hypoxia, the researchers isolated and immortalized lung endothelial cells from Arnt^loxP/loxP mice and maintained them in Lifeline® VascuLife® medium (although their experiments were done in alternative media). Upon Adeno-Cre treatment and hypoxic conditions, they demonstrated that cells lacking Arnt do not upregulate HIF target genes and fail to appropriately migrate and form capillary tubes well. In addition, the researchers demonstrated that in hypoxic conditions, Arnt-null primary lung or cardiac endothelial cells had decreased proliferation and survival compared to Arnt-expressing endothelial cells. Together, the results of this study illustrate that Arnt is critical for HIF protein function and the ability of endothelial cells to respond to hypoxic conditions.

Fibrosis is a complicated process that includes activation of multiple immune cell populations and inflammatory responses. Treatment of fibrosis with serum amyloid P (SAP) has been successful in mouse models of fibrosis and in human clinical trials for pulmonary fibrosis. SAP partially acts to prevent differentiation of monocytes into fibrocytes, a cell type that secretes extracellular matrix-modifying factors. In a 2014 study, Cox et al. investigated the mechanisms by which SAP affects immune cell function through Fcg receptors (FcgRs). The researchers used site-directed mutagenesis of SAP to identify which amino acid residues were required for its effects on different immune cell types and binding to particular FcgRs. Using human peripheral blood mononuclear cell isolates, they induced fibrocyte differentiation using different FcgR fragments in Lifeline® FibroLife® medium and investigated the ability of SAP to inhibit fibrocyte differentiation. They found that SAP bound different receptors on different cell types: FcgI on monocytes and FcgRIIa on neutrophils. They also demonstrated that SAP has different effects on different immune cell types: SAP binding to monocytes blocked fibrocyte differentiation, while binding to neutrophils decreased adhesion. Together, their results provide insights into the effects of SAP on immune cell populations and the mechanisms by which SAP may improve fibrosis in a clinical setting.

Lifeline® Cell Culture Media

Lifeline® offers optimized cell culture media for different tissue and cell types:

• VascuLife®: endothelial cell culture medium and smooth muscle cells culture medium
• BronchiaLife™: airway epithelial cell culture medium
• UroLife™: bladder epithelial cell culture medium
• OcuLife™:  corneal epithelial cell culture medium
• DermaLife: keratinocytes culture medium and melanocytes culture medium
• MammaryLife™: mammary epithelial cell culture medium
• RenaLife™: renal epithelial cell culture medium
• ProstaLife™: prostate epithelial cell culture medium
• FibroLife®: fibroblast culture medium
• StemLife: for mesenchymal stem cell differentiation in the undifferentiated state
• AdipoLife™: for induction of mesenchymal stem cell differentiation into adipocytes
• OsteoLife™: for induction of mesenchymal stem cell differentiation into osteocytes
• ChondroLife™: for induction of mesenchymal stem cell differentiation into chondrocytes

Let us know how you are using Lifeline® media to grow Lifeline® cells or any cell type. Your study could be featured here on our blog!