Cell culture under oxygen controlled conditions: an improvement towards more predictive results

Oxygen concentration in tissues is a key factor for cell and organ survival. In normal conditions, partial oxygen pressure (pO2) results in the balance between oxygen delivery and its consumption. Oxygen is transported, in mammals, by circulating red blood cells. Partial oxygen pressure in tissues varies widely, depending on their respective metabolic requirements and their functional status. In normal physiological conditions,  partial oxygen pressure is called physioxia. Any alteration of tissue environment leading to a decrease in partial oxygen pressure is called hypoxia. Hypoxic conditions have been observed in many different pathological situations like tumor development, obesity or transcient ischemia.

Hyaluronan (HA) Competitive ELISA standard curve (cat. nr 117K-1200-1ea)

Hyaluronic acid (HA), or hyaluronan, is an ubiquitous, very high molecular mass polysaccharide that has applications in a variety of fields, including cosmetics, some types of surgery (e.g. opthalmic) and regenerative medicine. It can even be present as a contaminant in some bio-production processes. HA has also been suggested as a possible biomarker for Alzheimer’s disease (AD).

HA acts as a molecular shock-absorber and stabilizer for cells. Its visco-elastic properties, biologically speaking, are valuable for separating tissue and maintaining shape. It is a key in tissue lubrication, and it may play a role in wound repair. It is the ideal choice for some implants, as it does not usually cause an immune response (contrary to what may happen with some biomaterials). Size of the HA used in therapy has an impact on its success. Usually, higher weight forms usually render longer benefits. For bio-production, however, smaller HA forms are usually the main concern.

So, depending on the reason why you are studying this marker, keep size in mind in order to choose the best assay to measure the HA levels in your experimental model. It is of key importance that whatever product you use, analysis of the HA sizes detected with it are clearly mentioned in the technical documentation.

Hyaluronic acid (HA) sandwich ELISA standard curve (direct assay cat. nr 117K-4800-1kit)

A post by my colleague Dr. Philippe Fixe is of great help for choosing the right assay!

It’s not that these assays will allow you to discriminate between high- and low-weight HA. What is intended here is that these assays will allow you to detect all or part of the HA forms depending on its weight. And that may be crucial, as you may be using the assay that does not detect the HA sizes relevant for your experiment.

It is also possible now to outsource HA measurements to an external lab performing regularly validated Hyaluronic acid-specific immuno-assays. As an example, Echelon’s Competitive or Sandwich HA ELISAs outsourcing by tebu-bio’s lab in cosmetology or drug discovery.

Any comments? Feel free to share them below!