Humans ; COVID-19 Vaccines/therapeutic use* ; HIV-1 ; Immunity, Humoral ; COVID-19/prevention & control* ; SARS-CoV-2

To further enhance the immune effect of the foot-and-mouth disease (FMD) virus-like particles (VLPs) vaccine, this study prepared FMDV VLPs-zeolitic imidazolate (framework-8, ZIF-8) complexes with different particle sizes. We used a biomimetic mineralization method with Zn²⁺ and 2-methylimidazole in different concentration ratios to investigate the effect of size on the immunization effect. The results showed that FMDV VLPs-ZIF-8 with three different sizes were successfully prepared, with an approximate size of 70 nm, 100 nm, and 1 000 nm, respectively. Cytotoxicity and animal toxicity tests showed that all three complexes exhibited excellent biological safety. Immunization tests in mice showed that all three complexes enhanced the titers of neutralizing and specific antibodies, and their immune effects improved as the size of the complexes decreased. This study showed that ZIF-8 encapsulation of FMDV VLPs significantly enhanced their immunogenic effect in a size-dependent manner.
Animals ; Mice ; Foot-and-Mouth Disease/prevention & control* ; Foot-and-Mouth Disease Virus ; Antibodies, Neutralizing ; Immunity, Humoral ; Immunization ; Vaccines, Virus-Like Particle ; Antibodies, Viral ; Viral Vaccines

Objective: To analyze the immunological characteristics and antibody changes of patients infected with the Omicron BA.1 and evaluate the possibility of secondary infection. Methods: A total of 104 patients infected with Omicron BA.1 in the Jinnan District of Tianjin from January 8 to February 2, 2022, were included in the study. The control group and case group were matched 1∶1 based on age, sex and vaccination status. Serum was collected from the case group and control group at 3, 6 and 9 months after infection. The serum levels of interleukin4 (IL-4), IL-5 and interferon-gamma (IFN-γ), as well as the positive rates of IgG, IgG1 and IgG2, were detected by ELISA. Results: The highest concentration of IFN-γ in the case group at 6 months after infection was 145.4 pg/ml, followed by a decrease in concentration. The concentrations of IL-4 and IL-5 began to decrease at 6 months after infection (all P<0.001). There was no significant difference in the IgG2 positive rate between the case group and the control group at 6 months after BA.1 infection. However, at 9 months, there was a significant decrease compared to the control group (P=0.003). The ratio of IFN-γ/IL4 at 3 months after infection in the case group was lower than that in the control group (P<0.001). There was no significant difference in the ratio between the case group and the control group at 9 months after infection. Conclusion: The cellular immune function has been impaired at 3 months after infection with BA.1, and the specific cellular immune and humoral immune functions decrease significantly after 6 months, and the risk of secondary infection increases.
Adult ; Humans ; Immunity, Humoral ; Coinfection ; Interleukin-4 ; Interleukin-5 ; Immunoglobulin G ; Interferon-gamma

Objective: To analyze the immunological characteristics and antibody changes of patients infected with the Omicron BA.1 and evaluate the possibility of secondary infection. Methods: A total of 104 patients infected with Omicron BA.1 in the Jinnan District of Tianjin from January 8 to February 2, 2022, were included in the study. The control group and case group were matched 1∶1 based on age, sex and vaccination status. Serum was collected from the case group and control group at 3, 6 and 9 months after infection. The serum levels of interleukin4 (IL-4), IL-5 and interferon-gamma (IFN-γ), as well as the positive rates of IgG, IgG1 and IgG2, were detected by ELISA. Results: The highest concentration of IFN-γ in the case group at 6 months after infection was 145.4 pg/ml, followed by a decrease in concentration. The concentrations of IL-4 and IL-5 began to decrease at 6 months after infection (all P<0.001). There was no significant difference in the IgG2 positive rate between the case group and the control group at 6 months after BA.1 infection. However, at 9 months, there was a significant decrease compared to the control group (P=0.003). The ratio of IFN-γ/IL4 at 3 months after infection in the case group was lower than that in the control group (P<0.001). There was no significant difference in the ratio between the case group and the control group at 9 months after infection. Conclusion: The cellular immune function has been impaired at 3 months after infection with BA.1, and the specific cellular immune and humoral immune functions decrease significantly after 6 months, and the risk of secondary infection increases.
Adult ; Humans ; Immunity, Humoral ; Coinfection ; Interleukin-4 ; Interleukin-5 ; Immunoglobulin G ; Interferon-gamma

OBJECTIVE: This study aimed to investigate the effects of Montanide ISA-720 and Naloxone (NLX) in Hepatitis B surface antigen (HBsAg) vaccine formulation on cytokine and long-lasting antibody responses. METHODS: First, the HBsAg was formulated in Montanide ISA-720 adjuvant and Naloxone at 5 and 10 mg/kg. The experimental mice were immunized three times at a 2-week interval, and then IL-4, IL-2, TNF-α, and IFN-γ cytokines; long-lasting IgG antibody responses 220 days after the last shot; and IgG1/IgG2a isotypes were assessed by ELISA. RESULTS: The HBsAg-Alum group exhibited the highest IL-4 cytokine response among the experimental groups, whereas NLX in HBsAg-MON720 vaccine formulation did not affect cytokine responses. In addition, NLX in Alum-based vaccine suppressed IL-4 cytokine response and increased the IL-2/IL-4 cytokine ratio. Moreover, HBsAg-MON720 was more potent than HBsAg-Alum in the induction of antibody responses, and NLX in Alum- and MON720-based vaccines induced long-lasting antibody responses. CONCLUSION NLX in Alum-based vaccine decreased IL-4 cytokine response, increased IL-2/IL-4 cytokine ratio, and improved long-lasting humoral immune responses in both vaccine formulations. Therefore, the adjuvant activity of NLX in the vaccine formulation depends on the type of adjuvant and the nature of the antigen in the vaccine formulation.
Adjuvants, Immunologic/pharmacology* ; Alum Compounds ; Animals ; Cytokines ; Hepatitis B Surface Antigens ; Hepatitis B Vaccines ; Immunity, Humoral ; Immunoglobulin G ; Interleukin-2 ; Interleukin-4 ; Mice ; Mice, Inbred BALB C ; Mineral Oil ; Naloxone/pharmacology* ; Tumor Necrosis Factor-alpha

In this study, cytometric beads array(CBA) was used to determine the immunoglobulin content in humoral immunity evaluation of biomedical materials. The bovine-derived acellular dermal matrix was selected as a test sample and implanted into Balb/C mice subcutaneously to 4 weeks according to the high, medium and low dose groups. Four weeks later, IgG1, IgG2a, IgG2b, IgG3, IgA, and IgM were measured by CBA. The data of the test group and the control group were analyzed statistically. The results showed that compared with the negative control group, there was no significant difference in the IgG3, IgA content in the positive control group, while the IgG1, IgG2a, IgG2b, and IgM contents were significantly higher than the negative control group; no significant differences were seen in the sample groups. The results show that the method is suitable for analysis of immunoglobulin content in humoral immunity evaluation of biomedical materials.
Animals ; Cattle ; Immunity, Humoral ; Immunoglobulin A ; Immunoglobulin G ; Immunoglobulin M ; Mice ; Mice, Inbred BALB C ; Mice, Inbred CBA

COVID-19 ; Humans ; Immunity, Cellular ; Immunity, Humoral ; SARS-CoV-2

OBJECTIVE: To evaluate the effect of intranasal immunization with CTA1-DD as mucosal adjuvant combined with H3N2 split vaccine. METHODS: Mice were immunized intranasally with PBS (negative control), or H3N2 split vaccine (3 μg/mouse) alone, or CTA1-DD (5 μg/mouse) alone, or H3N2 split vaccine (3 μg/mouse) plus CTA1-DD (5 μg/mouse). Positive control mice were immunized intramuscularly with H3N2 split vaccine (3 μg/mouse) and alum adjuvant. All the mice were immunized twice, two weeks apart. Then sera and mucosal lavages were collected. The specific HI titers, IgM, IgG, IgA, and IgG subtypes were examined by ELISA. IFN-γ and IL-4 were test by ELISpot. In addition, two weeks after the last immunization, surivival after H3N2 virus lethal challenge was measured. RESULTS: H3N2 split vaccine formulated with CTA1-DD could elicit higher IgM, IgG and hemagglutination inhibition titers in sera. Furthermore, using CTA1-DD as adjuvant significantly improved mucosal secretory IgA titers in bronchoalveolar lavages and vaginal lavages. Meanwhile this mucosal adjuvant could enhance Th-1-type responses and induce protective hemagglutination inhibition titers. Notably, the addition of CTA1-DD to split vaccine provided 100% protection against lethal infection by the H3N2 virus. CONCLUSION CTA1-DD could promote mucosal, humoral and cell-mediated immune responses, which supports the further development of CTA1-DD as a mucosal adjuvant for mucosal vaccines.
Adjuvants, Immunologic ; Administration, Intranasal ; Animals ; Cholera Toxin ; Female ; Immunity, Humoral ; Influenza A Virus, H3N2 Subtype ; immunology ; Influenza Vaccines ; Mice, Inbred BALB C ; Nasal Mucosa ; immunology ; Random Allocation ; Recombinant Fusion Proteins

OBJECTIVE: This study aimed to characterize the diagnostic and vaccine potential of a novel Mycobacterium tuberculosis antigen Rv0674. METHODS: To evaluate the diagnostic potential and antigenicity of Rv0674, IgG was evaluated using ELISA and interferon (IFN)-γ was done by using ELISpot assay among TB patients and healthy donors. For immunogenicity evaluation, BALB/c mice were immunized with Rv0674. Cytokine production was determined by cytokine release assay using an ELISA kit, and the antibodies were tested using ELISA. RESULTS: The results of serum Elisa tests showed that Rv0674 specific immunoglobulin G (IgG) response was higher in TB patients than negative controls. And Rv0674 had good performance in serological test with sensitivity and specificity of 77.1% and 81.1%, respectively. While it shows poor sensitivity and specificity of 26.23% and 79.69% for IFN-γ tests. In BALB/c mice, Rv0674 adjuvant by DDA/Poly I:C could also induce a high level of IFN-γ, interleukin-2 and interleukin-6 as well as a high IgG titer in both high- and low-dose groups indicating that Rv0674 is essential in humoral and cellular immunity. Moreover, the cytokine profile and IgG isotype characterized Rv0674 as a Th1/Th2-mixed-type protective immunity with the predominance of Th1 cytokines. CONCLUSION Rv0674 may be a good potential candidate for the development of TB serological diagnosis and a new TB vaccine.
Adult ; Aged ; Animals ; Antigens, Bacterial ; immunology ; Female ; Humans ; Immunity, Cellular ; Immunity, Humoral ; Male ; Mice ; Mice, Inbred BALB C ; Middle Aged ; Tuberculosis ; diagnosis ; immunology ; Young Adult

Myasthenia gravis (MG) is a prototypical antibody-mediated neurological autoimmune disease with the involvement of humoral immune responses in its pathogenesis. T follicular helper (Tfh) cells have been implicated in many autoimmune diseases. However, whether and how Tfh cells are involved in MG remain unclear. Here, we established and studied a widely-used and approved animal model of human MG, the rat model with acetylcholine receptor alpha (AChRα) subunit (R-AChR)-induced experimental autoimmune myasthenia gravis (EAMG). This model presented mild body-weight loss 10 days after the first immunization (representing the early stage of disease) and more obvious clinical manifestations and body-weight loss 7 days after the second immunization (representing the late stage of disease). AChR-specific pre-Tfh cells and mature Tfh cells were detected in these two stages, respectively. In co-cultures of Tfh cells and B cells, the number of IgG2b-secreting B cells and the level of anti-AChR antibodies in the supernatant were higher in the cultures containing EAMG-derived Tfh cells. In immunohistochemistry and immunofluorescence assays, a substantial number of CD4/Bcl-6 T cells and a greater number of larger germinal centers were observed in lymph node tissues resected from EAMG rats. Based on these results, we hypothesize that an AChR-specific Tfh cell-mediated humoral immune response contributes to the development of EAMG.
Animals ; B-Lymphocytes ; immunology ; Disease Models, Animal ; Female ; Immunity, Humoral ; Lymph Nodes ; immunology ; Myasthenia Gravis, Autoimmune, Experimental ; immunology ; Protein Subunits ; immunology ; Proto-Oncogene Proteins c-bcl-6 ; immunology ; Rats, Inbred Lew ; Receptor Cross-Talk ; Receptors, Cholinergic ; immunology ; T-Lymphocytes, Helper-Inducer ; immunology