Peripheral low-density granulocytes after colorectal cancer surgery in predicting recurrence.

BACKGROUND: Low-density granulocytes (LDGs) have been shown to be increased in the peripheral blood of patients with inflammatory and malignant diseases. This study evaluated LDGs in patients who underwent radical surgery for colorectal cancer (CRC) and their impact on survival. METHODS: Patients who underwent radical colectomy between 2017 to 2021 were screened for enrolment in the study. Peripheral blood was obtained in the operating room before and after surgery and cells were recovered from the mononuclear layer after density gradient preparations. The ratio of CD66b(+) LDG to CD45(+) leukocytes was determined with flow cytometry, and the association of the ratios with patient outcomes was examined. The main outcome of interest was recurrence-free survival (RFS). RESULTS: Out of 228 patients treated, 176 were enrolled, including 108 colonic and 68 rectal cancers. Overall, 38 patients were stage I, 30 were stage II, 72 were stage 3, and 36 were stage IV. The number of LDGs was markedly increased immediately after surgery and the proportion of LDGs correlated positively with operating time (r = 0.2806, P < 0.001) and intraoperative blood loss (r = 0.1838, P = 0.014). Purified LDGs produced high amounts of neutrophil extracellular traps after short-term culture and efficiently trapped tumour cells in vitro. The proportion of postoperative LDGs was significantly higher in 13 patients who developed recurrence (median 9 (range 1.63-47.0)) per cent versus median 2.93 ((range 0.035-59.45) per cent, P = 0.013). When cut-off values were set at 4.9 per cent, a higher proportion of LDGs was strongly and independently associated with decreased RFS (P = 0.005). In patients with stage III disease, adjuvant chemotherapy significantly improved RFS of patients with high ratios of LDGs, but not low LDGs. CONCLUSION: LDGs are recruited to circulating blood by surgical stress early in the postoperative interval after colectomy for colonic cancer and their postoperative proportion is correlated with recurrence.

Immune responses to Nippostrongylus brasiliensis and tuberculin protein in GATA-3-transgenic mice.

GATA-3 appears to be key to the Th2 response. However, few in vivo experiments have examined the function of GATA-3 in Th1 and Th2 immune responses. We developed two lines of GATA-3-transgenic (Tg) mice harboring the SRalpha or lck promoters and examined the Th2 immune responses of mice infected with the intestinal nematode Nippostrongylus brasiliensis and the Th1 responses with purified derivative of tuberculin (PPD) immunization. Numbers of peripheral blood eosinophils in all GATA-3-Tg mice increased 10- to 20-fold after primary infection with N. brasiliensis and 25-100-fold after secondary infection. The number of eosinophils in infected GATA-3-Tg mice was significantly higher than that in infected control littermates. Total IgE levels after primary infection in GATA-3-Tg mice were 8-450-fold increased, which was significantly higher than those of control mice. Mesenteric lymph node cells of infected GATA-3-Tg mice upon stimulation with N. brasiliensis antigen secreted more IL-5 and IL-13 than those of control mice. However, production of IL-4 and IFN-gamma were comparable between GATA-3-Tg and controls. Mice immunized with PPD were intradermally challenged with PPD to induce delayed type hypersensitivity (DTH). The amount of footpad swelling caused by the DTH reaction in GATA-3-Tg mice was significantly smaller than that of control littermates. Inguinal lymph node cells from GATA-3-Tg mice stimulated with PPD in vitro secreted more IL-5, IL-10 and less IFN-gamma than those of control littermates. These results suggested that Th1 and Th2 driven conditions enhance IL-5 production in GATA-3-Tg mice through the direct binding of GATA-3 to the IL-5 promoter region. The influence of GATA-3 on IL-13, IFN-gamma and IL-10 production varied according to the stimulating conditions. However, IL-4 production was not significantly elevated in GATA-3-Tg mice, indicating that IL-4 and IL-5 production was differentially regulated in these mice.

Th2 immune responses in GATA-3-transgenic mice infected with Heligmosomoides polygyrus.

To examine the participation of transcription factor GATA-3 in Th2 immune responses in vivo, we generated transgenic mice having several copies of GATA-3 with LCK promotor. Mice were infected with the intestinal nematode Heligmosomoides polygyrus to induce Th2 immune responses. Upon antigen stimulation, IL-5 and IL-13 production of mesenteric lymph node cells from H. polygyrus-infected mice, was significantly enhanced in GATA-3-transgenic mice compared with nontransgenic control mice. However, IL-4 production was the same in GATA-3-transgenic and control mice. H. polygyrus-infected GATA-3-transgenic mice exhibited significantly more peripheral blood eosinophils and total IgE levels compared with control mice. These results suggest that GATA-3 promotes IL-5 and IL-13 production, and that the function of these cytokines results in eosinophilia and hyper-IgE, respectively.