OBJECTIVE: The present study aimed to evaluate the immunogenicity of BA.2 variant receptor binding domain (RBD) recombinant protein formulated with CpG 1826 plus alum dual adjuvant. METHODS: The BA.2 variant RBD (residues 308-548) fusing TT-P ₂ epitope was obtained from prokaryotic expression system, purification technology and dialysis renaturation, which was designated as Sot protein. The soluble Sot protein formulated with CpG 1826 plus alum dual adjuvant was designated as Sot/CA subunit vaccine and then the BALB/c mice were intramuscularly administrated with two doses of the Sot/CA subunit vaccine at 14-day interval (day 0 and 14). On day 28, the number of effector T lymphocytes secreting IFN-γ and IL-4 in mice spleen were determined by enzyme-linked immunospot (ELISpot) assay. The serum IgG, IgG1 and IgG2a antibodies were examined by enzyme-linked immunosorbent assay (ELISA). In addition, the level of neutralizing antibodies (NAbs) induced by Sot/CA subunit vaccine was also evaluated by the microneutralization assay. RESULTS: The high-purity soluble Sot protein with antigenicity was successfully obtained by the prokaryotic expression, protein purification and dialysis renaturation. The Sot/CA subunit vaccine induced a high level of IgG antibodies and NAbs, which were of cross-neutralizing activity against SARS-CoV-2 BA.2 and XBB.1.5 variants. Meanwhile, Sot/CA subunit vaccine also induced a high level of effector T lymphocytes secreting IFN-γ (635.00 ± 17.62) and IL-4 (279.20 ± 13.10), respectively. Combined with a decreased IgG1/IgG2a ratio in the serum, which indicating Sot/CA subunit vaccine induced a Th1-type predominant immune response. CONCLUSION The Sot protein formulated with CpG 1826 plus alum dual adjuvant showed that the excellent cellular and humoral immunogenicity, which provided a scientific basis for the development of BA.2 variant subunit vaccines and references for the adjuvant application of subunit vaccines.
Animals ; COVID-19 Vaccines/immunology* ; Alum Compounds/pharmacology* ; Mice, Inbred BALB C ; Vaccines, Subunit/immunology* ; Mice ; SARS-CoV-2/immunology* ; Oligodeoxyribonucleotides/administration & dosage* ; Female ; Adjuvants, Immunologic ; COVID-19/immunology* ; Antibodies, Viral/blood* ; Immunogenicity, Vaccine ; Spike Glycoprotein, Coronavirus/immunology* ; Antibodies, Neutralizing/blood* ; Adjuvants, Vaccine ; Immunoglobulin G/blood*

Vaccination is an effective method for preventing influenza, and adjuvants can enhance the immune response intensity and persistence of influenza vaccines. However, there are currently shortcomings in clinical adjuvant approvals, ineffectiveness against weak antigens, and a tendency to cause headaches. Therefore, the development of safe and effective novel adjuvants for influenza vaccines is particularly important to enhance vaccine immunogenicity and safety. Given the wide range of sources, high safety, and biodegradability of traditional Chinese medicine(TCM), some studies have described it as a vaccine adjuvant. This article reviewed the current status and challenges of influenza vaccine adjuvants, summarized the types of TCM adjuvants, the safety and immunomodulatory effects of natural active ingredients from TCM combined with influenza vaccines, the role of TCM adjuvants in antigen storage, antigen presentation capability, immune cells and cytokines, and immune responses, and analyzed the advantages and disadvantages of TCM adjuvants compared with small molecule adjuvants, with the aim of promoting the clinical development and commercialization of TCM adjuvants for influenza vaccines.
Humans ; Influenza Vaccines ; Adjuvants, Immunologic/pharmacology* ; Medicine, Chinese Traditional ; Influenza, Human/prevention & control* ; Adjuvants, Pharmaceutic

In order to increase the ability of oil-emulsion adjuvant to stimulate cellular immunity, chitosan hydrochloride with positive charge was selected to stabilize oil-in-water emulsion (CHE). In this paper, model antigen ovalbumin was selected to prepare vaccines with emulsion adjuvant, commercial adjuvant or no adjuvant. The emulsion was characterized by measuring the particle size, electric potential and antigen adsorption rate. BALB/c mice were immunized by intramuscular injection. Serum antibody levels, the numbers of IL-4-secreting cells in splenocytes, cytotoxic T lymphocyte (CTL) response, and the expression of central memory T cells were measured to evaluate the immunostimulatory effect. The results showed that chitosan hydrochloride can effectively stabilize the emulsion. The emulsion size is about 600 nm, and the antigen adsorption rate is more than 90%. After immunization, CHE could increase serum antibodies levels and increase IL-4 secretion. Expression of CTL surface activation molecules was also increased to stimulate CTL response further and to increase the CD44⁺CD62L⁺ in T cells proportion. CHE as adjuvant can stimulate humoral and cellular immunity more efficiently, and is expected to extend the duration of protection.
Animals ; Mice ; Chitosan ; Interleukin-4 ; Emulsions ; Immunization ; Adjuvants, Immunologic/pharmacology* ; Antigens ; Mice, Inbred BALB C

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 recent years, the development of new vaccines such as nucleic acid vaccines, genetically engineered vaccines, and synthetic peptide vaccines has achieved rapid development. However, compared with traditional inactivated or live vaccines, these vaccines often have problems such as poor immunogenicity. Therefore, an adjuvant is needed to enhance its effect, and adjuvants have proven to be a key component in vaccines. There are many types of adjuvants, while currently no unified standard for the classification. At present, the most commonly used adjuvants are Aluminum adjuvant and Freund's adjuvant, but new generation vaccines will probably need new generation adjuvants. Thus, this review aims to showcase the current status of immune adjuvants, with the focus on immunomodulatory molecular adjuvant, antigen delivery adjuvant and compound adjuvant. This review provides new insights for the development of novel vaccine adjuvants.
Adjuvants, Immunologic/pharmacology* ; Freund's Adjuvant ; Vaccines ; Vaccines, Subunit

Listeria monocytogenes (Lm) is zoonotic pathogen that can cause listeriosis, and vaccine is one of the effective methods to prevent this pathogen infection. In this study, we developed a novel vaccine that is a mixture of inactivated bacteria and Montanide™ ISA 61 VG, a mineral oil adjuvant, and evaluated the safety and immune response characteristics of this vaccine. The mice immunized with the ISA 61 VG adjuvant had high safety, and it could induce significantly higher titer of anti-listeriolysin O (LLO) antibody and higher value of IgG2a/IgG1 ratio compared with the group without the adjuvant. In particular, it could provide 100% immune protection against lethal doses of Lm challenge in mice. In summary, ISA 61VG adjuvant significantly enhanced the ability of inactivated listeria vaccine to induce humoral and cellular immune responses, thereby enhanced the protective immune response in the host, and it is a potential vaccine candidate for the prevention of Lm infection in humans and animals.
Adjuvants, Immunologic ; pharmacology ; Animals ; Hemolysin Proteins ; immunology ; pharmacology ; Immunity, Cellular ; drug effects ; Listeria monocytogenes ; immunology ; Listeriosis ; prevention & control ; Mice ; Mice, Inbred BALB C ; Vaccines, Inactivated ; immunology

To explore the role of methotrexate (MTX) in regulating the number of regulatory T cells (Treg) and the mRNA expression of transcription factor Foxp3.
 Methods: 1) We analyzed the number of Treg and the mRNA expression of Foxp3 by flow cytometry (FCM) and quantitative real-time PCR (qRT-PCR) respectively in patients with psoriasis vulgaris, patients with psoriasis vulgaris after the 8-week treatment of MTX, and healthy people. 2) BALB/c female mice were smeared with imiquimod (IMQ) cream for 6 days. We recorded the change of the lesion in mice every day. The morphological changes of lesion in mice were evaluated by the psoriasis area and severity index (PASI) and HE staining. 3) The mouse model was randomly divided into a control group and an MTX group. The MTX group was treated with different doses of MTX (38.5 and 77.0 nmol/L) on the third day of this experiment. The morphological changes of lesion in mice were evaluated by PASI and HE staining. We tested the number of Treg and the expression level of Foxp3 mRNA in splenic lymphocytes.
 Results: 1) The number of Treg and the expression level of Foxp3 mRNA were lower in psoriasis vulgaris patients than those in the healthy control group (P<0.05). After 8-week treatment of MTX, the number of Treg was increased (P<0.05) and Foxp3 mRNA level was up-regulated (P<0.01). 2) Typical psoriasis-like skin lesions, such as red scaly skin plaque were found after topical application of IMQ. Both the number of Treg in the splenic lymphocytes of mice and the Foxp3 mRNA level of Treg were reduced by IMQ (P<0.01 and P<0.05). 3) Different doses of MTX for mice showed the ability to improve skin lesion, increase the number of Treg in the spleen of mice and Foxp3 mRNA level in psoriatic dermatitis of mice (P<0.05).
 Conclusion: MTX is able to regulate the number of Treg and Foxp3 mRNA expression in psoriasis.
Adjuvants, Immunologic ; pharmacology ; Aminoquinolines ; pharmacology ; Animals ; Case-Control Studies ; Female ; Forkhead Transcription Factors ; metabolism ; Humans ; Imiquimod ; Immunosuppressive Agents ; administration & dosage ; pharmacology ; Lymphocyte Count ; Methotrexate ; administration & dosage ; pharmacology ; Mice ; Mice, Inbred BALB C ; Psoriasis ; drug therapy ; immunology ; metabolism ; pathology ; RNA, Messenger ; metabolism ; Random Allocation ; Spleen ; cytology ; T-Lymphocytes, Regulatory ; cytology ; drug effects ; metabolism

OBJECTIVE: To investigate the effect of vitamin D3 on polarization of monocyte macrophages induced by serum from patients with ankylosing spondylitis (AS). METHODS: Twenty AS naïve patients and 20 healthy controls from Wenzhou People's Hospital during January 2016 and December 2017 were enrolled. The macrophages were differentiated from THP1 cells induced by phorbol 12-myristate 13-acetate (PMA), and then co-cultured with the serum from healthy subjects (control group) or AS patients. Vitamin D3 was added in the medium mixed with serum from AS patients. Flow cytometry was used to analyze the ratio of CD68 and CD206 positive cells, and RT-PCR was performed to detect the mRNA expression of inducible nitric oxide synthase(iNOS) and arginase-1(Arg-1). RESULTS: THP1 cells could be polarized into mononuclear-macrophages with the induction of PMA. The proportion of CD206 positive cells in AS-serum group was lower than that in the control group (=9.434, <0.05), while the proportion of CD68 positive cells was higher than that in the control group (=43.920, <0.05). The proportion of CD206 positive cells in vitamin D3 group was higher than that in AS-serum group (=8.895, <0.05), while the proportion of CD68 positive cells was lower than that in AS-serum group (=9.089, <0.05). mRNA expression of Arg-1 in AS-serum group was lower than that in the control group (=8.899, <0.05), while mRNA expression of iNOS was higher than that in the control group (=3.656, <0.05). mRNA expression of Arg-1 in vitamin D3 group was higher than that in AS-serum group (=6.219, <0.05), while mRNA expression of iNOS was lower than that in AS-serum group (=5.876, <0.05). CONCLUSIONS Vitamin D3 can regulate the polarization of mononuclear macrophages for immunoregulation in patients with AS.
Adjuvants, Immunologic ; pharmacology ; Cell Differentiation ; drug effects ; Cholecalciferol ; pharmacology ; Humans ; Monocytes ; drug effects ; Spondylitis, Ankylosing ; blood ; physiopathology

OBJECTIVETo investigate the effects of adipose-derived stem cells (ADSC) and non-methylated CpG-oligodeoxynucleotides (CpG-ODN) on the expression of peripheral blood CD4CD25regulatory T (Treg) cells in young mice with food allergy, as well as their immune intervention effects.

METHODSA total of 40 female BALB/c mice were randomly divided into control group, allergic group, ADSC treatment group, and CpG-ODN treatment group, with 10 mice in each group. A mouse model of food allergy was established by intraperitoneal injection and intragastric administration of ovalbumin (OVA) for sensitization and challenge. The mice in the control group were treated with normal saline at the same dose; the mice in the ADSC treatment group were given intraperitoneal injection of ADSC (1×10cells for each mouse) before and after OVA challenge, and those in the CpG-ODN treatment group were given intraperitoneal injection of non-methylated CpG-ODN solution (40 μg for each mouse) at 1 hour before challenge by gavage. The allergic symptom scores were determined for each group after model establishment. ELISA was used to measure the serum level of OVA-IgE. Flow cytometry was used to measure the percentage of peripheral blood CD4CD25Treg cells. Hematoxylin and eosin staining was used for the pathological analysis of the jejunum.

RESULTSThe allergic group had significantly higher allergic symptom scores and serum level of OVA-IgE than the control group (P<0.05). There were no significant differences in the allergic symptom score and the serum level of OVA-IgE between the ADSC treatment group and the CpG-ODN treatment group (P>0.05), but these two groups had significantly lower allergic symptom scores and serum level of OVA-IgE than the allergic group and significantly higher allergic symptom scores and serum level of OVA-IgE than the control group (P<0.01). The allergic group had a significantly lower percentage of peripheral blood CD4CD25Treg cells than the control group (P<0.05). The ADSC treatment group and the CpG-ODN treatment group had a significantly higher percentage of peripheral blood CD4CD25Treg cells than the allergic group (P<0.05); there were no significant differences between these two groups or between them and the control group (P>0.05). Pathological results showed structural damage and edema in the jejunal villi, a large number of eosinophils, and lymphocyte infiltration in the allergic group, while the ADSC treatment group and the CpG-ODN treatment group had less structural damage and edema in the jejunal villi, a lower number of eosinophils, and less lymphocyte infiltration.

CONCLUSIONSADSC and non-methylated CpG-ODN have a certain effect in the treatment of food allergy and can increase the percentage of peripheral blood CD4CD25Treg cells and reduce the level of OVA-IgE. They may be associated with the induction of immune tolerance and these two treatment have comparable effects. Detailed mechanisms of action still need further investigation.

Adipose Tissue ; cytology ; Adjuvants, Immunologic ; pharmacology ; Animals ; Female ; Food Hypersensitivity ; immunology ; therapy ; Immunoglobulin E ; blood ; Mice ; Mice, Inbred BALB C ; Oligodeoxyribonucleotides ; pharmacology ; Ovalbumin ; immunology ; Stem Cell Transplantation ; T-Lymphocytes, Regulatory ; drug effects ; immunology

Thymopentin (TP5) and bursopentin (BP5) are both immunopotentiators. To explore whether the TP5-BP5 fusion peptide (TBP5) has adjuvant activity or not, we cloned the TBP5 gene and confirmed that the TBP5 gene in a recombinant prokaryotic expression plasmid was successfully expressed in Escherichia coli BL21. TBP5 significantly promoted the proliferation of thymic and splenic lymphocytes of mice. The potential adjuvant activity of the TBP5 was examined in mice by coinjecting TBP5 and H9N2 avian influenza virus (AIV) inactivated vaccine. HI antibody titers, HA antibodies and cytokines levels (IL-4 and IFN-γ) were determined. We found that TBP5 markedly elevated serum HI titers and HA antibody levels, induced the secretion of both IL-4 and IFN-γ cytokines. Furthermore, virus challenge experiments confirmed that TBP5 contributed to inhibition replication of the virus [H9N2 AIV (A/chicken/Jiangsu/NJ07/05)] from mouse lungs. Altogether, these findings suggest that TBP5 may be an effective adjuvant for avian vaccine and that this study provides a reference for further research on new vaccine adjuvants.
Adjuvants, Immunologic ; pharmacology ; Animals ; Antibodies, Viral ; blood ; Cell Proliferation ; drug effects ; Influenza A Virus, H9N2 Subtype ; drug effects ; physiology ; Influenza Vaccines ; immunology ; Interferon-gamma ; immunology ; Interleukin-4 ; immunology ; Lymphocytes ; drug effects ; Mice ; Oligopeptides ; immunology ; Orthomyxoviridae Infections ; drug therapy ; Recombinant Fusion Proteins ; immunology ; Spleen ; cytology ; Thymopentin ; immunology ; Thymus Gland ; cytology ; Vaccines, Inactivated ; immunology ; Virus Replication