Escarra-Senmarti Marta, Bueno-Topete Miriam Ruth, Jave-Suarez Luis Felipe, Gomez-Bañuelos Eduardo, Gutierrez-Franco Jorge, Vega-Magaña Natali, Aguilar-Lemarroy Adriana, Pereira-Suarez Ana Laura, Haramati Jesse, Del Toro-Arreola Susana
Instituto de Enfermedades Crónico-Degenerativas, Departamento de Biología Molecular y Genómica, CUCS, Universidad de Guadalajara, Guadalajara, Jalisco, Mexico.
División de Inmunología, CIBO, Instituto Mexicano del Seguro Social, Guadalajara, Jalisco, Mexico.
Immunol Lett. 2017 Feb;182:30-38. doi: 10.1016/j.imlet.2017.01.006. Epub 2017 Jan 10.
CD28 is well characterized as an essential co-stimulatory receptor critical for activation, proliferation and survival processes in CD4 T cells. Populations of CD4CD28 T cells, with apparently contradictory physiological roles, have recently been reported, along with the co-expression of the NK activating receptor NKG2D, in autoimmune diseases and chronic viral inflammation. Paradoxically, studies in cancer suggest that an expanded CD4NKG2D population may be armed with immunosuppressive properties. We have recently reported the existence of two separate CD4NKG2D T cell populations, which were defined by the presence or absence of the co-stimulatory molecule CD28, with the CD4CD28NKG2D population more frequently observed in women with cervical cancer. This has led to the present effort to further characterize this population and to determine if the loss of CD28 influences the acquisition of cytotoxic or regulatory markers. In the present work, a multicolor flow cytometry protocol was used to analyze the expression of cytotoxic and immunoregulatory markers on circulating CD4 T cells characterized by the presence or absence of CD28 and NKG2D in patients with invasive cervical carcinoma and age/gender-matched healthy controls. A noticeable expansion of CD4CD28 cells, many of them NKG2D, were observed in selected cervical cancer samples. This CD4CD28 T cell population was characterized by a lack of immunoregulatory markers, as well as very low basal levels of intracellular IFN-γ, TNF-α, TGF-β, and IL-10. Intracellular perforin, however, was found to be significantly increased in this CD4CD28 population, and increases in the mean fluorescence intensity of perforin were found to be enhanced by the presence of NKG2D. In conclusion, our data provide the first evidence of a strict link between the absence of CD28 and the expression of perforin, which is likewise enhanced by the expression of NKG2D, within selected CD4 T cells from cervical cancer patients.
CD28作为一种重要的共刺激受体已得到充分表征，对CD4 T细胞的激活、增殖和存活过程至关重要。最近有报道称，在自身免疫性疾病和慢性病毒炎症中，出现了具有明显矛盾生理作用的CD4CD28 T细胞群体，同时还伴有NK激活受体NKG2D的共表达。矛盾的是，癌症研究表明，扩增的CD4NKG2D群体可能具有免疫抑制特性。我们最近报道了存在两个独立的CD4NKG2D T细胞群体，它们由共刺激分子CD28的存在与否来定义，在宫颈癌女性患者中更频繁地观察到CD4CD28NKG2D群体。这促使我们进一步表征该群体，并确定CD28的缺失是否会影响细胞毒性或调节性标志物的获得。在本研究中，采用多色流式细胞术方案分析浸润性宫颈癌患者及年龄/性别匹配的健康对照者循环CD4 T细胞上细胞毒性和免疫调节标志物的表达，这些CD4 T细胞以CD28和NKG2D的存在与否为特征。在选定的宫颈癌样本中观察到CD4CD28细胞显著扩增，其中许多细胞表达NKG2D。该CD4CD28 T细胞群体的特征是缺乏免疫调节标志物，以及细胞内IFN-γ、TNF-α、TGF-β和IL-10的基础水平非常低。然而，发现该CD4CD28群体中细胞内穿孔素显著增加，并且发现NKG2D的存在增强了穿孔素平均荧光强度的增加。总之，我们的数据首次证明了在宫颈癌患者的特定CD4 T细胞中，CD28的缺失与穿孔素的表达之间存在紧密联系，而NKG2D的表达同样增强了这种联系。
