Introduction to PBMC for cell immunotherapy

PBMC is an abbreviation for peripheral blood mononuclear cells. Note that here is the mononuclear cell, not the Monocyte monocyte, which refers to any peripheral blood cell that has a rounded nucleus. That is to say, PBMC is an immune lymphocyte derived from the blood of healthy animals.

These cells include lymphocytes (T cells, B cells, NK cells) and monocytes, and granulocytes (including neutrophils, basophils, and eosinophils) have multi-lobed nuclei, sometimes it is divided into this category [1].

Therefore, PBMC is not a kind of cell, but a mixed immune cell. And immune cells are the most important soldiers in the body against viral diseases. Lymphocytes, monocytes, and Neutrophil Granulocytes in PBMC have very strong anti-tumor (cancer cells) and anti-viral effects!

However, T cells and NK (Natural Killer) cells are most important lymphoid in PBMC.

A T cell, or T lymphocyte, is a type of lymphocyte (a subtype of white blood cell) that plays a central role in cell-mediated immunity. Their art various T cell types that actively respond immediately to a stimulus, such as co-stimulation. This includes T-helper (CD4 T), killer(CD8 T), regulatory (T reg), and potentially other T cell types. Memory cells are their opposite counterpart that are longer lived to target future infections as necessary.

NK cells, are a type of cytotoxic lymphocyte critical to the innate immune system. The role NK cells play is analogous to that of cytotoxic T cells in the vertebrate adaptive immune response. NK cells provide rapid responses to virus-infected cells and cancer cells.

Adoptive cell transfer (PBMC therapy)

The technique of adoptive cell transfer was used to study tumor immunity well over half a century ago [2]. Recently, a lot of works had established that T lymphocytes harvested from immune mice could protect syngeneic recipients from a subsequent tumor challenge and sometimes mediate rejection of established tumors [3].

In 2013, Kyle et al reported expanded PBMC from breast cancer patients which contained T cells and NK cells overcame tumor induced immune suppression and established long-lasting immune responses against the tumor [4]. In 2016, Veethika et al isolated healthy PBMC and examine the immune response in a mouse model with human ovarian cancer, where NK cells were found to be the effector cells that elicited an antitumor response. NK cells from PBMC has cytotoxic response to tumor in ovarian cancer patients [5].

Therefore, the use of a small number of healthy cats to donate PBMC to return to viral diseases, including FIP (cat peritonitis), FIV (cat AIDS), FeLV (cat leukemia) and various malignant tumors may have curative effect!

Reference:

1. Delves, Peter, et al. Roitt's Essential Immunology, 11th Ed. ISBN978-1-4051-3603-7
2. MITCHISON NA.Studies on the immunological response to foreign tumor transplants in the mouse. I. The role of lymph node cells in conferring immunity by adoptive transfer.J Exp Med. 1955 Aug 1;102(2):157-77.
3. Rosenberg SA, Terry WD.Passive immunotherapy of cancer in animals and man.Adv Cancer Res. 1977;25:323-88.
4. Kyle K Payne et al. Peripheral blood mononuclear cells of patients with breast cancer can be reprogrammed to enhance anti-HER-2/neu reactivity and overcome myeloid-derived suppressor cells.Breast Cancer Res Treat. 2013 Nov; 142(1): 45–57.Published online 2013 Oct 25. doi: 10.1007/s10549-013-2733-5
5. Veethika Pandey et al. Anti-ovarian tumor response of donor peripheral blood mononuclear cells is due to infiltrating cytotoxic NK cells.Oncotarget. 2016 Feb 9; 7(6): 7318–7328.Published online 2016 Jan 18. doi: 10.18632/oncotarget.6939