Viral immunology最新文献

We determined anti-rubella and anti-measles immunoglobulin G (IgG) in 7- to 19-year-old children and adolescents with vaccine only-induced immunity of Córdoba, Argentina, during a 6-month period over 2021-2022. Of the 180 individuals studied, 92.2% and 88.3% were positive for anti-measles and anti-rubella IgG, respectively. No significant differences were found comparing anti-rubella IgG concentrations (p = 0.144) and anti-measles IgG concentrations (p = 0.105) of individuals classified by age, but anti-measles IgG and anti-rubella IgG levels were significantly higher among female individuals compared with males (p = 0.031 and p = 0.036, respectively). Female subjects in the younger age group had higher concentrations of anti-rubella IgG as well (p = 0.020), even when anti-measles IgG concentrations did not differ among female age-subgroups (p = 0.187). In contrast, age subgroups of male individuals did not have significantly different IgG concentrations for rubella (p = 0.745) or measles (p = 0.124). Among samples with discordant results (22/180, 12.6%), 9.1% were negative for rubella but positive for measles; 13.6% were equivocal for rubella and positive for measles; 22.7% were equivocal for rubella and negative for measles, while 54.5% were positive for rubella but negative for measles. The findings indicate a seroprevalence below recommended for preventing measles in the population studied, while they evidence the need for standardization of serological tests for rubella IgG.

This study aims to analyze the achievements of coronavirus disease-2019 (COVID-19) vaccination in five provinces in Indonesia, North Maluku, West Sulawesi, Maluku, West Papua, and Papua. Furthermore, to establish herd immunity in the new normal perspective. Vaccination is important because it is an effective way to build immunity. This method uses qualitative research with a Qualitative Data Analysis Software (QDAS) approach. The source of data was obtained from the official website of the government, the ministry of health, in the category of areas with low vaccination achievement, and data were also obtained by capturing news in credible official media to find the cause of the low vaccination rate in the community. The data analyst uses NVivo12 software to code and visualizes data in graphs, images, and word clouds. The findings of this study indicate that in five provinces in Indonesia, North Maluku (68%), West Sulawesi (76%), Maluku (66%), West Papua (62%), and Papua (41%), the achievement of vaccination implementation is still relatively low. Due to doubts in the community about the status of the vaccine, information and communication education from the government have not been optimal; the environment and geography vary, so it becomes an obstacle in carrying out vaccination.

Few data are available on the impact of COVID-19 vaccination on CD4 counts and HIV-RNA in persons living with HIV (PLWH). We present the data of 235 PLWH who were vaccinated with BNT162b2 in March 2021-February 2022 at the "Cotugno" hospital in Naples. PLWH treated at the "Cotugno" hospital, who were vaccinated at the hospital vaccination center, without prior COVID-19 and for whom immunological/virological data were available in the last 12 months and in the 6 months after vaccination were included. Antispike Ab were available for 187 and 64 PLWH after the second and third doses: PLWH with antispikes >33 binding antibodies units (BAU)/mL increased from 91% to 98%. Antinucleocapsid Ab performed in 147 and 56 patients identified 19 (13%) asymptomatic/paucisymptomatic COVID-19 infections after the second dose and an additional 15 (27%) after the third dose. Immunological/virological data were collected before vaccination (T0), after the second dose (T1), and after the third dose (T2). The absolute number of CD4 increased after the third dose (median 663, 657, and 707 at T0, T1, and T2; p < 0.000 T0 vs. T2). The proportion of patients with HIV-RNA <50 copies/mL increases significantly after the second dose (73%; 85.7%; 87.7%; p < 0.000 T0 vs. T2). The presence of COVID-19 asymptomatic/paucisymptomatic infections (demonstrated by the presence of antinucleocapsid Ab) significantly increases SARS-CoV-2 antispike Ab after second dose, but not after third dose. Asymptomatic/paucisymptomatic COVID-19 infections do not have influence on CD4 cell number and HIV-RNA level. Similarly, the presence of not-controlled HIV-RNA (HIV-RNA >50 copies/mL) does not influence antispike Ab response. According to our data, the response to SARS-CoV2 vaccination is effective in people living with HIV. Vaccination against COVID-19 appears to positively affect immunological and virological levels in people living with HIV.

Coronavirus disease 2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), rapidly resulted in a pandemic constituting a global health emergency. As an indicator of long-term immune protection from reinfection with the SARS-CoV-2 virus, the presence of memory B cells (MBCs) should be evaluated. Since the beginning of COVID-19 pandemic, several variants of concerns have been detected, including Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1/B.1.1.28.1), Delta (B.1.617.2), and Omicron (BA.1) variants with several different mutations, causing serious concern regarding the increased frequency of reinfection, and limiting the effectiveness of the vaccine response. At this regard, we investigated SARS-CoV-2-specific cellular immune responses in four different cohorts: COVID-19, COVID-19 infected and vaccinated, vaccinated, and negative subjects. We found that MBC response to SARS-CoV-2 at more than 11 months postinfection was higher in the peripheral blood of all COVID-19 infected and vaccinated subjects respect to all the other groups. Moreover, to better characterize the differences of SARS-CoV-2 variants immune responses, we genotyped SARS-CoV-2-positive samples from the patients' cohort. We found a higher level of immunoglobulin M+ (IgM+) and IgG+ spike MBCs in SARS-CoV-2-positive patients (5-8 months after symptoms onset) infected with the SARS-CoV-2-Delta variant compared with the SARS-CoV-2-Omicron variant implying a higher immune memory response. Our findings showed that MBCs persist more than 11 months after primary infection indicating a different involvement of the immune system according to the different SARS-CoV-2 variant that infected the host.

FcγR is expressed by many immune cells and plays an important role in the immune response to hepatitis B virus (HBV) infection. CD32 belongs to the FcγR family. This study aimed to observe changes in CD32 expression by CD4⁺ T and CD8⁺ T lymphocytes in chronic HBV infection patients and evaluate the clinical utility of CD4⁺ T and CD8⁺ T CD32 expression to assess the severity of liver injury in chronic HBV-infected patients. A total of 68 chronic HBV patients and 40 healthy individuals were recruited, and the median fluorescence intensity (MFI) of CD32 expression on CD4⁺ T, CD8⁺ T lymphocytes was measured using flow cytometry and the CD4⁺ T, CD8⁺ T CD32 index was calculated. The reactivity of the healthy individual lymphocytes to mixed patients' plasma containing HBV was observed. Finally, the correlation between CD4⁺ T, CD8⁺ T lymphocytes CD32 MFI and liver function indicator levels was analyzed. The CD4⁺ T, CD8⁺ T CD32 MFI and index were significantly elevated in HBV patient groups than in normal control group (p < 0.001, for all). Furthermore, the CD32 MFI of healthy persons' CD4⁺ T and CD8⁺ T lymphocytes were remarkably increased when stimulated with mixed patients' plasma containing high HBV copies (p < 0.001; P < 0.001). More importantly, in HBV patients, there was a significant positive correlation between CD4⁺ T, CD8⁺ T CD32 MFI and the level of serum aspartate aminotransferase (p < 0.05, p < 0.05). In conclusion, the increased expression of CD32 on CD4⁺ T and CD8⁺ T lymphocytes might be potential promising biomarkers for the severity of liver function impairment in chronic HBV patients.

Epstein-Barr virus (EBV) is the first human oncogenic virus to be identified, which evades the body's immune surveillance through multiple mechanisms that allow long-term latent infection. Under certain pathological conditions, EBVs undergo a transition from the latent phase to the lytic phase and cause targeted dysregulation of the host immune system, leading to the development of EBV-related diseases. Therefore, an in-depth understanding of the mechanism of developing an immune response to EBV and the evasion of immune recognition by EBV is important for the understanding of the pathogenesis of EBV, which is of great significance for finding strategies to prevent EBV infection, and developing a therapy to treat EBV-associated diseases. In this review, we will discuss the molecular mechanisms of host immunological responses to EBV infection and the mechanisms of EBV-mediated immune evasion during chronic active infection.

Studies assessing the gut mucosal immune balance in HIV-infected patients using intestinal samples are scarce. In this study, we used intestinal mucosal specimens from the ileocecal region of seven immunological nonresponders (INRs), nine immunological responders (IRs), and six HIV-negative controls. We investigated T helper 17 (Th17) and T regulatory (Treg) cell counts and their ratio, zonula occludens-1 (ZO-1), intestinal fatty acid-binding protein (I-FABP), tumor necrosis factor-α, CD4⁺ T cell counts, HIV DNA, and cell-associated HIV RNA. The results showed that INRs had lower Th17 and higher Treg cell counts than IR, resulting in a significant difference in the Th17/Treg ratio between IRs and INRs. In addition, INRs had lower ZO-1 and higher I-FABP levels than IRs. The Th17/Treg ratio was positively associated with ZO-1 and negatively associated with I-FABP levels. There was a positive correlation between Th17/Treg ratio and CD4⁺ T cell counts and a negative correlation between the Th17/Treg ratio and HIV DNA in the intestine. Our study suggests that the imbalance of Th17/Treg in the intestine is a characteristic of incomplete immune reconstitution to antiretroviral therapy and is associated with intestinal damage.

Severe respiratory involvement that follows a process of immune dysregulation and intense cytokine production remains to be the most dreaded complication of Coronavirus Disease-2019 (COVID-19) infection. The aim of this study was to analyze T lymphocyte subsets and natural killer (NK) lymphocytes in moderate and severe cases of COVID-19 infection and assess their significance in disease severity and prognosis. Twenty moderate cases and 20 severe cases of COVID-19 were studied and compared regarding blood picture, biochemical markers, T lymphocyte population subsets, and NK lymphocytes, which were determined by flow cytometric analysis. On analyzing the flow cytometric data of T lymphocyte cells and their subsets and NK cells in two groups of COVID-19 infection (one group moderate and the other severe cases), some immature NK lymphocyte relative and absolute counts were higher in the severe patients with worse outcome and death, while some mature NK lymphocyte relative and absolute counts were depressed in both groups. Also, interleukin (IL)-6 was significantly higher in severe cases when compared to moderate cases, and there was a positive significant correlation between immature NK lymphocyte relative and absolute counts and IL-6. There was no statistically significant difference between T lymphocyte subsets (T helper and T cytotoxic) with disease severity or outcome. Some immature NK lymphocyte subsets contribute to the widespread inflammatory response that complicates severe cases of COVID-19; therapeutic approaches directed to enhancing NK maturation or drugs that block NK cell inhibitory receptors have a potential role in controlling COVID-19 induced cytokine storm.