Anti-CD8 (Hu) from Mouse (TC8)

dianova develops under the trademark “ONCOdianova” new antibodies for IHC detection of cancer immunology checkpoint biomarkers in FFPE-tissues.

Reactivity

Clone TC8 has been developed for the immunohistochemical (IHC) detection of CD8 in FFPE human tissue sections and validated for the identification of CD8 positive tumor infiltrating T cells (TILs). Anti-CD8 antibody (DIA-TC8) allows as yet unrivalled specific detection of CD8 in the tumor microenvironment.
CD8+ (cytotoxic) T cells can infiltrate different human tumors and are engaged in the development of a specific tumor microenvironment, which plays a central role in the killing of cancer cells. Cancer cells have developed the ability to generate immunosuppressive signals. Blockade of this interaction between cancer cells and immune cells is the key focus of modern immune checkpoint therapies. Preexisting CD8+ T cells seem to predict the efficacy of such immune checkpoint therapy.
T-cell receptors (TCR) recognize antigenic peptides presented on the surface of cancer and other target cells. These specific interaction trigger a TCR signaling transduction cascade, leading to execution of cytotoxic T lymphocyte (CTL) functions.
In contrast, inhibitory T-cell receptors such as PD-1, CTLA-4 and TIGIT are activated by the immunosuppressive tumor microenvironment with the aim to inactivate tumor-infiltrating lymphocytes (TILs). Effective blockade of such checkpoints by immunotherapy appears to be associated with the presence of CD8+ T cells.

Immunohistochemistry of human CD8 in routine formalin-fixed paraffin-embedded (FFPE) tissue samples

A: Adenocarcinoma of the lung with marked infiltration by CD8 positive lymphocytes
B: Dense infiltrate of CD8 positive lymphocytes in a serous carcinoma of the ovary
C: Clear cell kidney cancer with high number of CD8 positive lymphocytes
D: CD8 positive lymphocytes in a low grade tubular adenoma of the colon

(A) Lung Adenocarcinoma

B) Ovary carcinoma

(C) Kidney cancer

(D) Colon adenoma

(pictures courtesy of Prof. Guido Sauter, Department of Pathology, University Hospital Eppendorf, Hamburg, Germany)

References

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