Targeting TRIM29 As a Negative Regulator of CAR-NK Cell Effector Function to Improve Antitumor Efficacy of These Cells: A Perspective

Natural killer (NK) cells are among the most important cells in innate immune defense. In contrast to T cells, the effector function of NK cells does not require prior stimulation and is not MHC restricted. Therefore, chimeric antigen receptor (CAR)-NK cells are superior to CAR-T cells. The complexity of the tumor microenvironment (TME) makes it necessary to explore various pathways involved in NK cell negative regulation. CAR-NK cell effector function can be improved by inhibiting the negative regulatory mechanisms. In this respect, the E3 ubiquitin ligase tripartite motif containing 29 (TRIM29) is known to be involved in reducing NK cell cytotoxicity and cytokine production. Also, targeting TRIM29 may enhance the antitumor efficacy of CAR-NK cells. The present study discusses the negative effects of TRIM29 on NK cell activity and genomic deletion or suppression of the expression of TRIM29 as a novel approach to optimize CAR-NK cell-based immunotherapy.

Immune responses in mildly versus critically ill COVID-19 patients

The current coronavirus pandemic (COVID-19), caused by SARS-CoV-2, has had devastating effects on the global health and economic system. The cellular and molecular mediators of both the innate and adaptive immune systems are critical in controlling SARS-CoV-2 infections. However, dysregulated inflammatory responses and imbalanced adaptive immunity may contribute to tissue destruction and pathogenesis of the disease. Important mechanisms in severe forms of COVID-19 include overproduction of inflammatory cytokines, impairment of type I IFN response, overactivation of neutrophils and macrophages, decreased frequencies of DC cells, NK cells and ILCs, complement activation, lymphopenia, Th1 and Treg hypoactivation, Th2 and Th17 hyperactivation, as well as decreased clonal diversity and dysregulated B lymphocyte function. Given the relationship between disease severity and an imbalanced immune system, scientists have been led to manipulate the immune system as a therapeutic approach. For example, anti-cytokine, cell, and IVIG therapies have received attention in the treatment of severe COVID-19. In this review, the role of immunity in the development and progression of COVID-19 is discussed, focusing on molecular and cellular aspects of the immune system in mild vs. severe forms of the disease. Moreover, some immune- based therapeutic approaches to COVID-19 are being investigated. Understanding key processes involved in the disease progression is critical in developing therapeutic agents and optimizing related strategies.

Targeting T Cell Metabolism as a Novel Approach for Treatment of MS: With a Focus on PFKFB3 Inhibitors

Abstract:

Multiple sclerosis (MS) is one of the organ-specific autoimmune diseases in which immune cells invade the neurons in the central nervous system (CNS) due to loss of tolerance to self-antigens. Consequently, inflammation and demyelination take place in the central nervous system. The pathogenesis of MS is not completely understood. However, it seems that T cells, especially Th17 cells, have an important role in the disease development. In recent years, studies on manipulation of metabolic pathways with therapeutic targets have received increasing attention and have had promising results in some diseases such as cancers. Glycolysis is a central metabolic pathway and plays an important role in the differentiation of T CD4+ cell toward its subsets, especially the Th17 cells. This suggests that manipulation of glycolysis, by for example using appropriate safe inhibitors of this pathway, can represent a means to affect the differentiation of T CD4+, thus reducing inflammation and disease activity in MS patients. Hence, in this study we aimed to discuss evidence showing that using inhibitors of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3(PFKFB3), as the main regulator of glycolysis, may exert beneficial effects on MS patients.

Comparison of the Antibody Responses Following Vaccination with AstraZeneca and Sinopharm

BACKGROUND

Vaccines are the most effective way to prevent Coronavirus 2 severe acute respiratory syndrome (SARS-CoV-2).

OBJECTIVES

To compare the antibody response of healthy individuals vaccinated with either the AstraZeneca (ChAdOx1 nCoV-19) or the Sinopharm (BBIBP-CorV) vaccine, in those who had no prior infection with SARS-CoV-2.

METHODS

Thirty seven participants were included, of which 17 were administered the AstraZeneca (ChAdOx1 nCoV-19) vaccine, while 20 were given the Sinopharm (BBIBP-CorV) vaccine. SARS-CoV-2 neutralizing antibody and anti-receptor-binding domain (RBD) IgG levels were checked 4 weeks after giving the first and the second dose of either vaccine using the enzyme-linked immunosorbent assay (ELISA) technique.

RESULTS

The AstraZeneca (ChAdOx1 nCoV-19) vaccine exhibited a higher levels of anti-(RBD) IgG compared with the Sinopharm (BBIBP-CorV) in both the first (14.51 μg/ml vs. 1.160 μg/ml) and the second (46.68 μg/ml vs. 11.43 μg/ml) doses. About neutralizing Abs, the titer of the antibody was higher in the AstraZeneca (ChAdOx1 nCoV-19) recipients than in the Sinopharm (BBIBP-CorV) subjects after the first (7.77 μg/ml vs. 1.79 μg/ml, p < 0.0001) and the second dose (10. 36 μg/ml vs. 4.88 μg/ml, p < 0.0001).

CONCLUSIONS

Recipients vaccinated with two doses of the AstraZeneca (ChAdOx1 nCoV-19) had superior quantitative antibody levels than Sinopharm (BBIBP-CorV)-vaccinated subjects. These data suggest that a booster dose may be needed for the Sinopharm (BBIBP-CorV) recipients, to control the COVID-19 pandemic.

Lower frequency of T stem cell memory (TSCM) cells in hepatitis B vaccine nonresponders

Despite the availability of an effective vaccine and antiviral treatments, hepatitis B is still a global public health problem. Hepatitis B vaccination can prevent the disease. Vaccination induces long-lasting protective immune memory, and the identification of memory cell subsets can indicate the effectiveness of vaccines. Here, we compared the frequency of CD4⁺ memory T cell subsets between responders and nonresponders to HB vaccination. Besides, the frequency of IFN-γ⁺ memory T cells was compared between studied groups. Study participants were grouped according to their anti-HBsAb titer. For restimulation of CD4⁺ memory T cells, peripheral blood mononuclear cells (PBMCs) were cultured in the presence of HBsAg and PHA for 48 h. Besides, PMA, ionomycin, and brefeldin were added during the last 5 h of incubation to induce IFN-γ production. Flow cytometry was used for analysis. There was a statistically significant difference in the frequency of CD4⁺CD95⁺, CD4⁺CD95^Hi, and CD4⁺CD95^low/med T stem cell memory (T_SCM) cells between responder and nonresponder groups. However, the comparison of the frequency of memory T cells producing IFN-γ showed no differences. Our results identified a possible defect of immunological CD4⁺ memory T cell formation in nonresponders due to their lower frequency of CD4⁺ T_SCM cells.

Prevalence of Enterobius vermicularis amongst kindergartens and preschool children in Mazandaran Province, North of Iran

Enterobiasis (oxyuriasis) is probably the most common helminth, which infects humans. Amongst different age groups, prevalence of Enterobius vermicularis in children is high compared to adults. Oxyuriasis is one of the most significant parasitic diseases of children. This nematode in children can result in loss of appetite, insomnia, grinding of the teeth, restlessness, endometritis, abdominal cramps, diarrhea and etc. Due to important complications of this parasite, the objective of the current study was to determine the prevalence of enterobiasis in kindergarten and preschool children of Amol, Mazandaran Province, North of Iran. A total number of 462 children from 32 kindergartens of Amol were examined for the prevalence of E. vermicularis infection, 2013. Adhesive cello-tape anal swab method was trained to parents for sampling. In addition, a questionnaire was designed and filled out to collect demographic information for each individual. Data were analyzed using Chi square test and multivariate logistic regression for each risk factor. The overall prevalence of E. vermicularis infection was 7.1 % (33). Although infection with E. vermicularis in girls 7.9 % was higher compared to boys 6.3 %, there was no significant difference between gender and age (p > 0.05) whereas binary logistic regression showed significant difference between enterobiasis and age (p < 0.05). The findings indicated that the prevalence of E. vermicularis in kindergarten and preschool children is relatively high and still is an important health problem and should not be underestimated due to being highly contagious infection. Therefore, educational programs and mass treatment should be carried out in order to reduce infection incidence in this area and regular parasitological test and attention to personal hygiene in kindergarten and preschool is of great importance.