Cancer Immune Therapy Edited by G. Stuhler and P. Walden ...

98 6 Immune Cells in the Tumor Microenvironment
Fig. 6.2 T lymphocytes in the tumor
microenvironment. In (A), a mass of
HLA-DR + T cells surrounds the tumor.
Immunoperoxidase staining of the
biopsy obtained from a patient with
head and neckcancer. Original magnification:
× 400. In (B), a cluster of CD8 + T
cells (red) infiltrating a human head and
neckcancer. Apoptotic T cells (TUNEL +
whitish) are evident among the CD8 + T
cells. A TUNEL reagent was used in
combination with immunoperoxidase
staining. Original magnification: × 400.
Dr T. E. Reichert, U. Mainz, Germany
contributed Fig. 2(B). (see color plates
page XXV)
sial issue, with evidence ushered in support of as well as against the TIL involvement
in the control of tumor growth [12]. Figure 6.2(A) depicts the tumor surrounded by a
mass of lymphocytes. In an effort to summarize the body of available literature, it is
necessary to stress that not all tumors are similarly well infiltrated or surrounded by
immune cells, and that both the size and the composition of tumor infiltrates vary
widely even among the tumors of the same histologic type. The diagram shown in
Fig. 6.3 indicates that cells mediating innate as well as adaptive immunity may be
present at the tumor site. Further, a variety of soluble products, including cytokines
and antibodies, may be released by these cells in response to non-specific or tumor-
Fig. 6.3 Diagram depicting interactions
of various immune cells with the
tumor. In the presence of immune cells,
the tumor is expected to fail. Instead, it
usually continues to progress.