Clinical Immunology Communications最新文献

Pre-existing SARS-CoV-2-specific T cells, but not antibodies, have been detected in some unexposed individuals. This may account for some of the diversity in clinical outcomes ranging from asymptomatic infection to severe COVID-19. Although age is a risk factor for COVID-19, how age affects SARS-CoV-2-specific T cell responses remains unknown. We found that pre-existing T cell responses to specific SARS-CoV-2 proteins, Spike (S) and Nucleoprotein (N), were significantly lower in elderly donors (>70 years old) than in young donors. However, substantial pre-existing T cell responses to the viral membrane (M) protein were detected in both young and elderly donors. In contrast, young and elderly donors exhibited comparable T cell responses to S, N, and M proteins after infection with SARS-CoV-2. These data suggest that although SARS-CoV-2 infection can induce T cell responses specific to various viral antigens regardless of age, diversity of target antigen repertoire for long-lived memory T cells specific for SARS-CoV-2 may decline with age; however, memory T cell responses can be maintained by T cells reactive to specific viral proteins such as M. A better understanding of the role of pre-existing SARS-CoV-2-specific T cells that are less susceptible to age-related loss may contribute to development of more effective vaccines for elderly people.

In Pakistan, the Hepatitis E virus (HEV) is prevalent. HEV exposure is deadly during pregnancy, with high infection rates in both the mother and the baby, even in asymptomatic situations. The researcher examined HEV-negative pregnant women with acute hepatitis or increased renal characteristic assessments at 12 medical sites in Khyber Pakhtunkhwa, Pakistan, to identify maternal and fetal disease risks from August to December 2018. Except for one during the entire pregnancy, twenty-five of the 135 females were HEV-free and in the perinatal period. HEV infection was found in 0.19% of newly pregnant women. Also, 11 cases of forcible induction of labor, 7 cases of normal labor, 5 cases of normal labor (full-term), 2 cases of death, and 1 case of intrauterine death were reported before going to the doctor a girl had an abortion. There were eight postpartum deaths: five from infections, four from miscarriages, and two from miscarriages. While 18 mothers who survived voluntarily or intentionally induced abortions and three women who continued to get pregnant but did not deliver died as a result of abortion. The current study found that HEV infection during pregnancy raised the death rate by 14.2%.

Paroxysmal nocturnal hemoglobinuria (PNH) is a non-malignant clonal disorder of the pluripotent hematopoietic stem cell. Currently, Eculizumab, Ravulizumab, and Pegcetacoplan are the approved drugs to treat PNH. In order to assess the efficacy and safety of different medications available for PNH, we performed a systematic search. The primary efficacy endpoint was the percentage change in lactate dehydrogenase, transfusion avoidance, and stabilized hemoglobin. Key secondary endpoints included the proportion of patients with breakthrough hemolysis, anemia, adverse events, number of deaths, and discontinuation of treatment. From 2526 articles retrieved from electronic databases and manual searches, a total of five studies were included in this review: 1 observational study and 4 randomized clinical trials. For all efficacy and safety endpoints, Ravulizumab and Pegcetacoplan achieved noninferiority compared with the first standardized treatment Eculizumab. The use of complement inhibition therapy can further improve hematological outcomes in PNH patients.

Imprinting of the specific molecular image of a given protein antigen into immunological memory is one of the hallmarks of immunity. A later contact with a related, but different antigen should not trigger the memory response (because the produced antibodies would not be effective). The preferential expansion of cross-reactive antibodies, or T-lymphocytes for that matter, by a related antigen has been termed the original antigenic sin and was first described by Thomas Francis Jr. in 1960. The phenomenon was initially described for influenza virus, but also has been found for dengue and rotavirus. The antibody dependent enhancement observed in feline coronavirus vaccination also may be related to the original antigenic sin. For a full interpretation of the effectivity of the immune response against SARS-CoV-2, as well as for the success of vaccination, the role of existing immunological memory against circulating corona viruses is reviewed and analyzed.

Human telomerase reverse transcriptase (hTERT) is broadly expressed in many cancers. High hTERT expression have been described in chronic lymphocytic leukemia (CLL). Here we investigated the relationship between anti-hTERT immunity and disease progression in 49 CLL patients. Anti-hTERT T cell responses were evaluated by IFNγ-ELISpot. Complementary flow cytometry analyses were performed, and data were analyzed in regards of the treatment received by CLL patients afterward and disease progression. Anti-hTERT responses were more frequently observed in non-progressive watch and wait patients, and in progressive patients scheduled to receive ibrutinib, as compared to patients scheduled to receive other types of treatment. In vitro, addition of the anti-PD-1 antibody nivolumab increased anti-hTERT responses. Importantly, Kaplan Meier analyses showed significantly longer progression-free survival in patients with anti-hTERT immune responses at diagnosis as compared to non-responder patients. Our results show that anti-hTERT T cell responses represent a new potential biomarker predictive of CLL clinical outcome.

The beneficial immunomodulation effects of a biological response modifier glucan (BRMG) produced by two strains of Aureobasidium pullulans, AFO-202 and N-163, have already been reported. Herein, we compared their efficacy on immune-inflammatory parameters in Sprague Dawley (SD) rats. This study was performed on four groups of healthy SD rats, n=6 in each group: Group 1, euthanised on Day 0 for baseline values; Group 2, control (drinking water); Group 3, AFO-202 beta glucan, 200 mg/kg/day; and Group 4, N-163 beta glucan, 300 mg/kg/day. The neutrophil to lymphocyte ratio (NLR) decreased and leukocyte-to C-reactive protein ratio (LeCR) increased in Group 3 (AFO-202) at 15 and 29 days whereas the lymphocyte to C-reactive protein ratio (LCR) increased in group 4 (N-163), within the normal physiological range. These promising results warrant further investigations in larger numbers of healthy and diseased models to develop appropriate strategies for balancing immune system dysregulation.

Antibody deficiencies constitute the majority of primary immunodeficiencies in adults. These patients have a well-established increased risk of bacterial infections but there is a lack of knowledge regarding the relative risks upon contracting COVID-19. In this monocentric study the disease course of COVID-19 in 1 patient with Good's syndrome and in 13 patients with common variable immunodeficiency (CVID) is described. The severity of disease ranged from very mild to severe. Several patients required hospitalization and immunomodulatory treatment but all survived. Although viral infections are not a typical feature of humoral immunodeficiencies we recommend that vigilance is increased in the management of patients with Good's syndrome and CVID during the COVID-19 pandemic.

Myasthenia gravis (MG) is an autoimmune disease characterised by muscular degeneration and autoantibodies to components of the neuromuscular junction. Development of MG is thought to occur from a combination of genetic and environmental factors, and viral infections have been suggested to be involved in the onset of MG through molecular mimicry and/or chronic inflammation. In this work, we analysed sera from MG patients for antibodies to members of the human herpes virus family and other selected pathogens to determine the virus antibody status in the sera of these patients. Enzyme-linked immunosorbent assay, western blotting and line blotting analyses using MG serum pools showed an association between elevated IgG antibody titers to cytomegalovirus (CMV) and MG. These results were replicated using individual serum samples, and showed significant differences in CMV antibody titer between MG patients and healthy controls. Other viruses did not show the same tendency.