Marlen Vitales-Noyola; Diana Lorena Alvarado-Hernández; Raquel Sánchez-Gutiérrez; Berenice Hernández-Castro; Larisa González-Baranda; Sofía Bernal-Siva; Andreu Comas-García; Carmen Sánchez-Torres; Roberto González-Amaro
Abstract
Background: Clinical manifestations SARS-CoV-2 infection are variable, ranging from asymptomatic to pneumonia, and different serious complications. It has been observed that some populations exhibit an enhanced risk for severe disease and death, compared to other ethnical groups.Objective: To evaluate ...
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Background: Clinical manifestations SARS-CoV-2 infection are variable, ranging from asymptomatic to pneumonia, and different serious complications. It has been observed that some populations exhibit an enhanced risk for severe disease and death, compared to other ethnical groups.Objective: To evaluate two parameters of the innate immune system, which have a relevant role in viral immunity.Methods: In samples of peripheral blood from sixteen patients with severe COVID-19, ten with asymptomatic-mild disease, and fifteen healthy controls, the numbers of NK and NKT cells, the expression of different NK cell receptors and the serum levels of pro-inflammatory cytokines were analyzed.Results: We found that patients with severe COVID-19 showed significant lower levels of both CD56dim and CD56bright NK cells compared to patients with mild disease or healthy subjects. Furthermore, an abnormal expression of the natural cytotoxicity receptors NKp30, NKp44 and NKp46 was observed in severe COVID-19 patients. Likewise, NK cells from these patients also showed significant differences in the expression of several killer immunoglobulin-like receptors (KIR’s), in the two main cell subsets (CD56bright, CD56dim), compared to controls or patients with mild disease. Moreover, patients with severe COVID-19 showed lower levels of NKT cells (defined as CD3+CD56+) and increased serum concentrations of IL-6 and IL-8.Conclusion: We consider that the abnormalities in NK and NKT cells observed in patients with severe COVID-19 might have a relevant role in the outcome of this infection in some population groups.
Ali Shams; Sahar Khosravi; Aysan Zareiye; Yeganeh Lalehzari; Reyhane Nematollahi; Solmaz Basti
Abstract
Cell-mediated immunity (CMI) is crucial in controlling the highly aggressive and progressive SARS-CoV-2 infection. Despite extensive researches on severe COVID-19 infection, the etiology and/or mechanisms of lymphopenia, decreased T cell-mediated responses in patients, cytokine release storms (CRS), ...
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Cell-mediated immunity (CMI) is crucial in controlling the highly aggressive and progressive SARS-CoV-2 infection. Despite extensive researches on severe COVID-19 infection, the etiology and/or mechanisms of lymphopenia, decreased T cell-mediated responses in patients, cytokine release storms (CRS), and enhanced pro-inflammatory mediators are not fully understood. Several T cell subpopulations, including innate-like lymphocytes (ILLs) and conventional T cells, are involved in COVID-19 infection; however, their contribution to immunity and complications remains to be more elucidated. CD16+ T cells are among the effective players in the development of T helper1 (Th1) responses in COVID-19 infection, while their robust cytolytic properties contribute to lung tissue damage. While CD56-CD16bright NK cells play a protective role, natural killer T (NKT) cells, mucosal-associated invariant T (MAIT) cells, and γδ T cells and their roles in COVID-19 require further investigation. The involvement of the other T cell subsets, such as Th17, along with neutrophils, adds to the complexity of the situation. In this review, we presented and discussed the findings of recent studies on T cell responses and the contribution of each type of immune cells to COVID-19.
Alireza Norouzi; Shohreh Taziki; Ali Najafipasandi; Saeed Mohammadi; Gholamreza Roshandel
Abstract
Background: Natural killer (NK) cells are dichotomously involved in chronic hepatitis B (CHB) infection as principal members of innate immunity. An effective treatment should enhance the antiviral potentials of NK cells and not their immunomodulatory roles. TIM-3 (T-cell immunoglobulin and mucin-containing ...
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Background: Natural killer (NK) cells are dichotomously involved in chronic hepatitis B (CHB) infection as principal members of innate immunity. An effective treatment should enhance the antiviral potentials of NK cells and not their immunomodulatory roles. TIM-3 (T-cell immunoglobulin and mucin-containing domain) is a molecule with an essential role in controlling immune tolerance. TIM-3 demonstrated the highest expression among NK cells of patients with chronic liver disorders. Statins have been reported to attenuate the levels of TIM-3 on NK cells.Objectives: To investigate the frequencies of NK cells, NKT cells, and TIM-3+ population in patients with CHB upon rosuvastatin (RSV) intervention.Methods: Thirty confirmed patients with CHB were randomly assigned into two groups of 15 (receiving 20 mg of RSV or placebo per day) for 12 weeks. We evaluated the percentages of TIM-3+ cells by staining the peripheral blood mononuclear cells (PBMCs) with CD3, CD16, and CD56 markers using flow cytometry.Results: Our findings indicated that RSV administration could increase CD3- CD56+ NK cells (P>0.05) and CD3+ CD16+ CD56+ NKT cells (P<0.05). RSV intervention could reduce the percentages of TIM-3+ cells among NK cells (P<0.01) and NKT cells (P> 0.05) of patients with CHB compared with the placebo group.Conclusions: The increased population of NK and NKT cells and the effective reduction of TIM-3+ cells among patients with CHB delineated that rosuvastatin could be proposed as an appropriate modulator of innate immune response (regarding NK and NKT cells) in favor of enhancing their antiviral activities.
Somayeh Rezaeifard; Akbar Safaei; Abdolrasoul Talei; Zahra Faghih; Nasrollah Erfani
Abstract
Background: NK (natural killer) and NKT (natural killer T) cells, as components of innate immune system, play a crucial role in tumor progression and dissemination. Objective: To investigate the percentages of NK cells, NKT cells, iNKT (invariant natural killer T) cells, total T lymphocytes as well as ...
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Background: NK (natural killer) and NKT (natural killer T) cells, as components of innate immune system, play a crucial role in tumor progression and dissemination. Objective: To investigate the percentages of NK cells, NKT cells, iNKT (invariant natural killer T) cells, total T lymphocytes as well as activated T lymphocytes, in tumor draining lymph nodes (TDLNs) of patients with breast cancer (BC) and their association with different clinic-pathological features of the patients. Methods: Axillary lymph nodes were obtained from 30 Iranian women with breast cancer. After routine pathological evaluations, mononuclear cells were separated from their lymph nodes and incubated with appropriate fluorochrome conjugated monoclonal antibodies specific for CD3, HLA-DR, CD16/56, and Vα24Jα18-TCR. Data were collected on a four-color flow cytometer and analyzed by CellQuest software. Results: The mean percentages of NK (CD3-CD16/56+), NKT (CD3+CD16/56+) and iNKT (Vα24Jα18-TCR+) cells in TDLNs mononuclear cells of BC patients were 2.04%, 2.44% and 0.1%, respectively. A significant decrease in the percentages of NK and iNKT subsets in patients with grade I was observed compared to grade III (p=0.03 and p=0.01, respectively). Moreover, NK cells were increased in patients with grade III of BC compared to grade II (p= 0.003). Conclusion: The increase in the percentage of NK and iNKT cells in TDLNs of patients with higher grade of BC might suggest a suppressive phenotype for these cells in breast cancer, which merit more functional investigation.
