I would like to isolate macrophages from tissues as well as different tumors from mice and I can not find an appropriate protocol for it.
Adipose tissue macrophages (ATM) modulate cancer cell function. Therefore, ATM cell are isolated and compared with monocyte-derived macrophages (MDM) from the same obese patients. ATM, but not MDM, were found to secrete factors inducing inflammation and lipid accumulation in human T47D and HT-29 cancer cells. Gene expression profile comparison of ATM and MDM revealed overexpression of functional clusters, such as cytokine-cytokine receptor interaction (especially CXC-chemokine) signaling as well as cancer-related pathways, in ATM. Comparison with gene expression profiles of human tumor-associated macrophages showed that ATM, but not MDM resemble tumor-associated macrophages. In indirect co-culture experiments few importnat factors are secreted by preadipocytes, but not mature adipocytes, confer an ATM-like phenotype to MDM. By using ATM related sceretory growth factors in culture media can assist in separation of both types of cells or use Flow cytometry for actual cell separation.
Use MACS. I always successfully isolated microglia from brain and spinal cord using CD11B MACS beads. For macrophages you need to use AntiF4/80-PE ab (130-102-943 Miltenyi) then anti-PE microbeads (130-048-801).
A detailed protocol provided by Watkins et al (2012) for isolation of enriched populations of antigen presenting cells and tumor antigen-specific cytotoxic T lymphocytes from mice prostate tissue full text at: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3471300/
Cho et al (2014) published a very useful protocol in Methods in Enzymology detailing the isolation and subsequent identification of adipose tissue macrophages. The protocol could probably be adapted for other tissues, too.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4244227/
For the preliminary approaches in macrophage isolation, you can proceed with the sterile remove of biological material (tissue or tumor), gently break it into small pieces and leave incubate in plastic Petri dishes at 37 °C in an appropriate medium; after 1-2 h washing and refresh medium, therefore the majority of the detached cells and/or dead cells are discard. After 18-24 h, usually, the cellular populations able to remain attached to plastic dishes are tumor cells (if presents) and macrophages; but the tumor cells are removal by a fast trypsinization (after washing with PBS) whereas the macrophages are very adhesive. It is true that the macrophagic populations are 'multifarious': the macrophage are different in the state of activation, in their differentiation, in the molecular secretion profiles, etc, in their morphology, also depending organ tissue. By these macrophage cultures, you can initiate to study many properties of those macrophages that you find specifically.
Sure, after these cognitive investigations, it needs other techniques for the their selective isolation.
There are plenty of published reports in the literature. Follow a suitable one
Here is a nice review with a number of relevant citations in Nature Immunology
Tissue-resident macrophages
Luke C Davies1, Stephen J Jenkins2, Judith E Allen3 & Philip R Taylor1
Tissue-resident macrophages are a heterogeneous population of immune cells that fulfill tissue-specific and niche-specific functions. These range from dedicated homeostatic functions, such as clearance of cellular debris and iron processing, to central roles in tissue immune surveillance, response to infection and the resolution of inflammation. Recent studies highlight marked heterogeneity in the origins of tissue macrophages that arise from hematopoietic versus self-renewing embryo-derived populations. We discuss the tissue niche-specific factors that dictate cell phenotype, the definition of which will allow new strategies to promote the restoration of tissue homeostasis. Understanding the mechanisms that dictate tissue macrophage heterogeneity should explain why simplified models of macrophage activation do not explain the extent of heterogeneity seen
in vivo
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