In the course of the coronavirus disease 2019 (COVID-19), raising and reducing the function of Th17 and Treg cells, respectively, elicit hyperinflammation and disease progression. The current study aimed to evaluate the responses of Th17 and Treg cells in COVID-19 patients compared with the control group. Forty COVID-19 intensive care unit (ICU) patients were compared with 40 healthy controls. The frequency of cells, gene expression of related factors, as well as the secretion levels of cytokines, were measured by flow cytometry, real-time polymerase chain reaction, and enzyme-linked immunosorbent assay techniques, respectively. The findings revealed a significant increase in the number of Th17 cells, the expression levels of related factors (RAR-related orphan receptor gamma [RORγt], IL-17, and IL-23), and the secretion levels of IL-17 and IL-23 cytokines in COVID-19 patients compared with controls. In contrast, patients had a remarkable reduction in the frequency of Treg cells, the expression levels of correlated factors (Forkhead box protein P3 [FoxP3], transforming growth factor-β [TGF-β], and IL-10), and cytokine secretion levels (TGF-β and IL-10). The ratio of Th17/Treg cells, RORγt/FoxP3, and IL-17/IL-10 had a considerable enhancement in patients compared with the controls and also in dead patients compared with the improved cases. The findings showed that enhanced responses of Th17 cells and decreased responses of Treg cells in 2019-n-CoV patients compared with controls had a strong relationship with hyperinflammation, lung damage, and disease pathogenesis. Also, the high ratio of Th17/Treg cells and their associated factors in COVID-19-dead patients compared with improved cases indicates the critical role of inflammation in the mortality of patients.
There are little information about Th17 cells and cutaneous Leishmaniasis (CL), due to an important effect of Th17 cells on immune response, it is worth to explore the role of Th17 on CL. The purpose of this study was to assess Th17 population in patients with acute vs. chronic CL lesions in comparison with skin samples collected from healthy volunteers in an endemic region of Old World CL. A total of 49 patients with clinical manifestations of chronic (n=16) and acute (n=33) CL lesions were recruited. The clinical diagnosis of CL was confirmed by direct smear or PCR. Biopsy specimens from prelesional skin of non-infectious lesions of 30 healthy individuals were used as control. Tissue sections of 3µm thickness were prepared and used for immunohistochemistry (IHC) analysis with primary antibody specific for Th17 associated antigen (CD161). For IHC, Envision+ (DakoCytomation) system was used and developed by using diaminobenzidine (DakoCytomation). The mean age of 33 patients with acute CL and the mean age of 16 patients with chronic CL were accordingly 45.24±16.43 and 33.56±15.87. In acute and chronic CL the mean (±standard deviation) and median (±interquartile range) were accordingly 2.92±2.21, 2.56±2.9 and 2.1±1.99, 1.54±2.81. In healthy controls the mean (±standard deviation) and median (±interquartile range) were 0.72±0.41 and 0.61±0.58 respectively. With pairwise comparison of acute, chronic and control groups, there were significant difference between acute and control (P value < 0.001), chronic and control (P value = 0.043). The results showed that there was an increasing cellular response of Th17 in both acute and chronic CL patients. Th17 was significantly higher in patients with acute and chronic CL lesions in comparison with healthy control group. However, there was no significant difference between acute and chronic infection concerning to Th17 cells.
Tropomyosin receptor kinase C (TrkC) targeted ligand-photosensitizer construct, IYIY-diiodo-boron-dipyrromethene (IYIY-I2-BODIPY) and its scrambled counterpart YIYI-I2-BODIPY have been prepared. IYIY-I2-BODIPY binds TrkC similar to neurotrophin-3 (NT-3), and NT-3 has been reported to modulate immune responses. Moreover, it could be shown that photodynamic therapy (PDT) elevates antitumor immune responses. This prompted us to investigate the immunological impacts mediated by IYIY-I2-BODIPY in pre- and post-PDT conditions. We demonstrated that IYIY-I2-BODIPY (strong response) and YIYI-I2-BODIPY (weak response) at 10 mg/kg, but not I2-BODIPY control, increased the levels of IL-2, IL-4, IL-6 and IL-17, but decreased the levels of systemic immunoregulatory mediators TGF-β, myeloid-derived suppressor cells and regulatory T-cells. Only IYIY-I2-BODIPY enhanced the IFN-γ+ and IL-17+ T-lymphocytes, and delayed tumor growth (~20% smaller size) in mice when administrated daily for 5 days. All those effects were observed without irradiation; when irradiated (520 nm, 100 J/cm2, 160 mW/cm2) to produce PDT effects (drug-light interval 1 h), IYIY-I2-BODIPY induced stronger responses. Moreover, photoirradiated IYIY-I2-BODIPY treated mice had high levels of effector T-cells compared to controls. Adoptive transfer of immune cells from IYIY-I2-BODIPY-treated survivor mice that were photoirradiated gave significantly delayed tumor growth (~40-50% smaller size) in recipient mice. IYIY-I2-BODIPY alone and in combination with PDT modulates the immune response in such a way that tumor growth is suppressed. Unlike immunosuppressive conventional chemotherapy, IYIY-I2-BODIPY can act as an immune-stimulatory chemotherapeutic agent with potential applications in clinical cancer treatment.
Steroidal agent is a standard clinical treatment of atopic dermatitis; however, have serious side effects. Artesunate is reported to exhibit anti-inflammatory properties although its effect on atopic eczema remains unknown. We investigated the therapeutic effects and possible mechanism of systemic artesunate on DNCB-induced atopic dermatitis in a BALB/c mouse model. To ascertain artesunate (5 and 10 mg/kg) efficacy, skin dermatitis severity and ear, spleen, and lymph node weight were evaluated. Skin tissue mRNA and protein expression and serum cytokine levels were examined. Artesunate significantly improved atopic dermatitis symptoms, decreasing the dermatitis score, ear weight difference, spleen weight, and lymph node weight compared with those following DNCB treatment. Artesunate reduced ear and skin epidermal thickness and mast cell infiltration, as determined using hematoxylin-eosin and toluidine blue staining, respectively. The basal level of IgE (287.67 ± 70.41 ng/ml) and TNF-α (19.94 ± 3.98 pg/ml) were Significantly elevated by DNCB (IgE: 1273.23 ± 176.53 ng/ml; TNF-α: 57.53 ± 3.87 pg/ml), while markedly been suppressed in the treatment group (AS-L: IgE: 1100.25 ± 135.32 ng/ml; TNF-α: 38.47 ± 3.26 pg/ml; AS-H: IgE: 459.46 ± 74.75 ng/ml; TNF-α: 24.38 ± 3.85 pg/ml). Among Th17 cell-related factors, DNCB treatment increased mRNA expression of IL-6, IL-17, IL-23, STAT3, and ROR-γt, but reduced TGF-β and SOCS 3; While artesunate reverse these changes. Compared with the model group, artesunate promoted SOCS3 protein and significantly inhibited ROR-γt protein and STAT3 phosphorylation. Thus, artesunate attenuates DNCB-induced atopic dermatitis by inhibiting the release of inflammatory cytokines and downregulating Th17 cell responses in atopic dermatitis mice.