Fig. 1

Frequency of circulating CD4⁺NKG2D⁺ T cells in patients with established cervical carcinoma. Multicolor flow cytometric analysis was performed to measure the expression of NKG2D on peripheral CD4⁺ T cells from both healthy donors and cervical cancer patients. Lymphocytes were gated according to FS and SS characteristics and sub-gated around CD3⁺ and CD4⁺ T cells; subsequently, NKG2D expression was evaluated. Bars in (a) represent the distribution of samples with varying levels of CD4⁺NKG2D⁺ T cells within the control and patient groups. Based on previous results, here our data were stratified in three different ranges of CD4⁺NKG2D⁺ T cells (0–2, 2–4, and >4 %). A significant increase in the frequency of CD4⁺NKG2D⁺ T cells in the group of cervical cancer patients was found, while some 68 % of the different control samples expressed very low CD4⁺NKG2D⁺ T cells (0–2 %) (χ ²(2) = 6.531; p = 0.038). A representative example of this disparity is shown in (b), where 18 % of the cancer patient’s CD3⁺CD4⁺ T cells are positive for NKG2D (lower panel), while only 1.4 % of the healthy control’s CD3⁺CD4⁺ T cells show this staining (upper panel)