Hi,

in serum (do not contain red or white cells) you may follow miRNAs that are basically carried in exosomes (as RNA cargo), secreted by cells. In whole blood you may follow miRNA expression in your (target) cell(s) plus exosomes. Purification of your (target) cell(s) from whole blood (if you are studying miRNa expression in cells contained in the blood)  will reduce your analysis to miRNAs expressed just in those cells.

Regards,

D

Hello

please , See these attachments , i hope help you

Good Luck

Dear Meaghan

microRNA are present in Organs , Tissue, Cell and Circulating Body fluids. So we can able to isolate from any one.

If you are interested to check   microRNA expression in clinical samples(effect of injury), 

Advantage:

Tissue injury  specific microRNA might change  whole blood homeostasis, then these whole blood will circulate into other parts of body to carry miR and transfer , it may lead to modulate different biogenesis  of cells.

Disadvantage :

Whole Blood contain WBC, RBC, Platelets, immune cells, circulating Nucleic acid. So its  very difficult to distinguish which one became biomarker.

If you interested to check circulating miRNA expression, I will suggest you to check  2 ways. Because during tissue injury microRNA release into circulation ( serum or plasma or exosomes).

1. Serum specific microRNA detection (because serum contain no cells, so you will get  tissue injury specific microRNA).

2.  Exosomes specific microRNA detection (because exosome are secreted from tissues,cells and body fluids. and its have novel mechanism  to communicate genetic information from cell to cell and  organ to organ), so exosomes  specific microRNA  might distinguish  between healthy and disease patients and it will be very useful for the  development of novel therapeutics.

So reply which one your going to proceed, then we will discuss methodology. 

with regards 

pp

 Dear Prabu, i am trying to address a similar question as Meaghan, to study miRNA expression from the serum of patients with a disease. In the lab we will use probably exosomes specific miRNA detection. Could you please give me some advice regarding the methodology? I've heard it' s quite complicated to obtain a pure exosomal fraction by ultra-centrifugation, and many people treat the sample with RNase to get rid of free-circulating RNAs that are present in the serum....Thanks. Renata

Dear Renata Cerna

I am using Exosome isolation from [ miRCURY Exosome Isolation kit from Exiqon ] followed RNA isolation from [ miRCURY RNA Isolation Kit from Exiqon ]. 

and I am not using ultracentrifucation method.

Please any further clarification please let me know.

with regards

pp