Identification of dendritic cells, B cell and T cell subsets in Tasmanian devil lymphoid tissue; evidence for poor immune cell infiltration into devil facial tumors

Abstract

The Tasmanian devil is under threat of extinction due to the transmissible devil facial tumor disease (DFTD). This fatal tumor is an allograft that does not induce an immune response, raising questions about the activity of Tasmanian devil immune cells. T and B cell analysis has been limited by a lack of antibodies, hence the need to produce such reagents. Amino acid sequence analysis revealed that CD4, CD8, IgM, and IgG were closely related to other marsupials. Monoclonal antibodies were produced against CD4, CD8, IgM, and IgG by generating bacterial fusion proteins. These, and commercial antibodies against CD1a and CD83, identified T cells, B cells and dendritic cells by immunohistochemistry. CD4+ and CD8+ T cells were identified in pouch young thymus, adult lymph nodes, spleen, bronchus‐ and gut‐associated lymphoid tissue. Their anatomical distribution was characteristic of mammalian lymphoid tissues with more CD4+ than CD8+ cells in lymph nodes and splenic white pulp. IgM+ and IgG+ B cells were identified in adult lymph nodes, spleen, bronchus‐associated lymphoid tissue and gut‐associated lymphoid tissue, with more IgM+ than IgG+ cells. Dendritic cells were identified in lymph node, spleen and skin. This distribution is consistent with eutherian mammals and other marsupials, indicating they have the immune cell subsets for an anti‐tumor immunity. Devil facial tumor disease tumors contained more CD8+ than CD4+ cells, but in low numbers. There were also low numbers of CD1a+ and MHC class II+ cells, but no CD83+ IgM+ or IgG+ B cells, consistent with poor immune cell infiltration. Anat Rec, 297:925–938, 2014. © 2014 The Authors. The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology Published by Wiley Periodicals, Inc.

Toll-like receptor signaling is functional in immune cells of the endangered Tasmanian devil

“…Previous studies have shown that the Tasmanian devil has the full complement of cells, tissues and organs that are required for a response against DFTD cells (Howson et al, 2014;Kreiss et al, 2008Kreiss et al, , 2009aWoods et al, 2007). Devils are capable of recognising allogeneic skin grafts and can respond to DFTD cells upon vaccination (Kreiss et al, 2015).…”

“…An absence of the major histocompatibility complex class I (MHC-I) at the cell surface means that tumour cells are not rejected by the Tasmanian devil's immune system and are free to progress into a new tumour at the wound of the recipient (Siddle et al, 2013). Established tumours have poor immune cell infiltration, suggesting that little natural immunity against DFTD exists (Howson et al, 2014;Loh et al, 2006).…”

Immunology of a Transmissible Cancer Spreading among Tasmanian Devils

“…T lymphocytes expressed cell surface CD3, monocytes expressed MHC class II (MHC-II), and B lymphocytes expressed CD79 (34). Identification of lymphocyte subsets required the development of specific mAbs (35). This allowed the identification of CD4 + and CD8 + T cells in the thymus, adult lymph nodes, spleen, BALT, and GALT.…”

“…Lymph nodes, spleen, BALT, and GALT contained IgM + and IgG + B cells. Based on the expression of CD1a, CD83, and MHC-II, dendritic cells were identified in the lymph node, spleen, and skin (35). Consequently, Tasmanian devils have the appropriate immune system components for effective immunity.…”

Genomic insights into a contagious cancer in Tasmanian devils

“…The immune system does not recognise DFTD cells; immune cell infiltration into the tumour is poor [37] and DFTD-specific antibodies are not produced [38]. As a result, the immune system is not activated and tumour progression continues unimpeded.…”