Bordetella bronchiseptica is a potent and safe adjuvant that enhances the antigen-presenting capability of dendritic cells

We previously demonstrated that Bordetella bronchiseptica (B. bronchiseptica) antigen (Ag) enhances the Mycoplasma hyopneumoniae Ag-specific immune response. The focus of this study was whether acellular bacterin of B. bronchiseptica could be used as an adjuvant to increase antigen-presenting capability of dendritic cells (DCs) by increasing the level of activation. The metabolic activity of DCs was increased by B. bronchiseptica, similar to lipopolysaccharide (LPS). Flow cytometry analysis revealed that B. bronchiseptica increases the expression of major histocompatibility complex class-2, cluster of differentiation (CD)40, CD54, and CD86 which are closely related to DC-mediated immune responses. B. bronchiseptica enhanced the production of cytokines related to adaptive immune responses. Furthermore, the survival rate of B. bronchiseptica-injected groups was 100% at 15 and 20 mg/kg doses, whereas that of LPS-injected groups was only 20%, 0% at 15 and 20 mg/kg doses respectively, and so B. bronchiseptica is likely to be safer than LPS. Taken together, these results indicate that B. bronchiseptica can be used as an adjuvant to enhance the antigen-presenting capability of DCs. B. bronchiseptica is a candidate for producing vaccines, especially in case of DC-mediating efficacy and safety demands. This study provides researchers and clinicians with valuable information regarding the usage of B. bronchiseptica as a safe bacteria-derived immunostimulating agent for developing efficient vaccines.

Samsum ant venom modulates the immune response and redox status at the acute toxic dose in vivo

Background:Ant venoms express surface molecules that participate in antigen presentation involving pro- and anti-inflammatory cytokines. This work aims to investigate the expression of MHC-II, CD80 and CD86 on the polymorphonuclear cells (PMNs) in rats injected with samsum ant venom (SAV).Methods:Rats were divided into three groups - control, SAV-treated (intraperitoneal route, 600 μg/kg), and SAV-treated (subcutaneous route, 600 μg/kg). After five doses, animals were euthanized and samples collected for analysis.Results:The subcutaneous SAV-trated rats presented decreased levels of glutathione with increased cholesterol and triglyceride levels. Intraperitoneal SAV-treated animals displayed significantly reduced concentrations of both IFN-γ and IL-17 in comparison with the control group. However, intraperitoneal and subcutaneous SAV-treated rats were able to upregulate the expressions of MHC-II, CD80 and CD86 on PMNs in comparison with the control respectively. The histological examination showed severe lymphocyte depletion in the splenic white pulp of the intraperitoneal SAV-injected rats.Conclusion:Stimulation of PMNs by SAV leads to upregulation of MHC-II, CD 80, and CD 86, which plays critical roles in antigen presentation and consequently proliferation of T-cells. Subcutaneous route was more efficient than intraperitoneal by elevating MHC-II, CD80 and CD86 expression, disturbing oxidative stability and increasing lipogram concentration.

Human leukocyte antigen-associated severe cutaneous adverse drug reactions: from bedside to bench and beyond

Despite their being uncommon, severe cutaneous adverse drug reactions (SCARs) result in a very great burden of disease. These reactions not only carry with them a high mortality (10%–50%) and high morbidity (60%) with severe ocular complications, alopecia, oral and dental complications and development of autoimmune diseases, but also create a substantial economic burden for patients' families and society. SCARs are, therefore, an important medical problem needing a solution in many countries, especially in Asia. The clinical spectrum of SCARs comprises Stevens-Johnson syndrome, toxic epidermal necrolysis, DRESS (drug rash with eosinophilia and systemic symptoms) (also known as drug hypersensitivity syndrome or drug-induced hypersensitivity syndrome) and acute generalised exanthematous pustulosis. Recent crucial advances in determining genetic susceptibility and understanding how T cells recognise certain medications or their metabolites via the major histocompatibility complex and the effects of cofactors, have led to the implementation of cost-effective screening programs enabling prevention in a number of countries, and to further understanding of the patho-mechanisms involved in SCARs and their significance. In this review, we document comprehensively the journey of SCARs from bedside to bench and outline future perspectives in SCARs research.

Loss of Human Leukocyte Antigen Class I Expression Is Associated with Poor Prognosis in Patients with Advanced Breast Cancer

BACKGROUND: Human leukocyte antigen class I (HLA-I) molecules play important roles in regulating immune responses. Loss or reduction of HLA-I expression has been shown to be associated with prognosis in several cancers. Regulatory T-cells (Tregs) also play critical functions in immune response regulation. Evaluation of HLA-I expression status by the EMR8-5 antibody and its clinical impact in breast cancer have not been well studied, and its relationship with Tregs remains unclear. METHODS: We evaluated HLA-I expression and Treg infiltration by immunohistochemistry in 465 surgically resected breast cancer samples. We examined the correlation between HLA-I expression and Treg infiltration and clinicopathologic characteristics and survival analyses were performed. RESULTS: Total loss of HLA-I expression was found in 84 breast cancer samples (18.1%). Univariate survival analysis revealed that loss of HLA-I expression was significantly associated with worse disease-specific survival (DSS) (p = .029). HLA-I was not an independent prognostic factor in the entire patient group, but it was an adverse independent prognostic factor for DSS in patients with advanced disease (stage II–IV) (p = .031). Treg numbers were significantly higher in the intratumoral stroma of HLA-I–positive tumors than in HLA-I–negative tumors (median 6.3 cells/high power field vs 2.1 cells/high power field, p < .001). However, Tregs were not an independent prognostic factor in our cohort. CONCLUSIONS: Our findings suggest that the loss of HLA-I expression is associated with poor prognosis in breast cancer patients, highlighting the role of HLA-I alterations in immune evasion mechanisms of breast cancer. HLA-I could be a promising marker that enables the application of more effective and precise immunotherapies for patients with advanced breast cancer.

The degree of major histocompatibility complex matching between purebred Maltese and mongrel dogs using microsatellite markers

Long-term maintenance of transplanted organs is one of the major factors that increases survival time of recipients. Although obtaining a major histocompatibility complex (MHC)-matched donor with the recipient is essential for successful organ transplantation, there have been limited reports on MHC matching between dogs. In this study, we analyzed the canine MHC matching rates using Maltese, one of the most popular purebred dogs, and mongrel dogs in Korea. Genomic DNA was extracted from blood leukocytes and DNA was amplified by polymerase chain reaction with primers specific to MHC microsatellite markers. The MHC matching degree was confirmed by the microsatellite markers using polyacrylamide gel electrophoresis. The MHC matching rates of each donor-recipient groups including Maltese-Maltese, mongrel-mongrel and Maltese-mongrel were 4.76%, 5.13% and 6.67%, respectively. There were no significant differences in the MHC matching degree between each group. These results demonstrate that MHC-matched donors could be selected from other breeds as much as from the same breed for transplantation. Knowledge of the MHC matching degree of purebred and mongrel dogs would offer valuable information not only for improving the success rate of organ transplantation surgery in canine patients but also for transplantation research using experimental canine models.

Intranasal Treatment With 1, 25-Dihydroxyvitamin D3 Alleviates Allergic Rhinitis Symptoms in a Mouse Model

PURPOSE: Vitamin D is a potent immunomodulator. However, its role in the pathogenesis of allergic rhinitis is unclear. METHODS: The aim of this study was to evaluate the antiallergic effect of intranasally applied vitamin D in an allergic rhinitis mouse model. BALB/c mice were intraperitoneally sensitized with ovalbumin (OVA) and alum before they were intranasally challenged with OVA. Then, they were intranasally administered 1, 25-dihydroxyvitamin D3 (0.02 μg) or solvent. Allergic symptom scores, eosinophil infiltration, cytokine mRNA levels (interleukin [IL]-4, IL-5, IL-10, IL-13 and interferon-γ) in the nasal tissue, and serum total immunoglobulin E (IgE) and OVA-specific IgE, IgG1, and IgG2a were analyzed and compared with negative and positive control groups. Cervical lymph nodes (LNs) were harvested for flow cytometry analysis and cell proliferation assay. RESULTS: In the treatment group, allergic symptom scores, eosinophil infiltration, and mRNA levels of IL-4 and IL-13 were significantly lower in the nasal tissue than in the positive control group. The IL-5 mRNA level, serum total IgE, and OVA-specific IgE and IgG1 levels decreased in the treatment group; however, the difference was not significant. In the cervical LNs, CD86 expression had been down-regulated in CD11c+major histocompatibility complex II-high (MHCIIhigh) in the treatment group. Additionally, IL-4 secretion in the lymphocyte culture from cervical LNs significantly decreased. CONCLUSIONS: The results confirm the antiallergic effect of intranasal 1,25-dihydroxyvitamin D3. It decreases CD 86 expression among CD11c+MHCIIhigh cells and T-helper type 2-mediated inflammation in the cervical LNs. Therefore, topically applied 1,25-dihydroxyvitamin D3 can be a future therapeutic agent for allergic rhinitis.

O feto é um ser alogênico de sucesso / The fetus is a successful allogeneic being

O feto é um ser alogênico de sucesso. O feto é um aloenxerto natural bem tolerado pelo organismo materno. Vários fatores contribuem para a tolerância materna ao feto: 1. O útero é um local do corpo imunologicamente privilegiado, protegido por uma barreira tecidual não imunogênica; 2. A promoção de uma resposta imunossupressora local pela mãe: a. A molécula HLA-G do MHC de classe Ib, expressa nas células da placenta, impede que as células NK matem a placenta; b. A catabolização do aminoácido essencial triptofano pela placenta impede que as células T da mãe tenham acesso ao feto; c. A secreção das citocinas TGF-ß, IL-4 e IL-10, pelo epitélio uterino e trofoblasto, tende a suprimir as respostas das células T da mãe; d. A secreção das citocinas TGF-ß e IL-10, pelas células T reguladoras, também inibe as respostas de células T maternas.(AU)

The fetus is a successful allogeneic being. The fetus is a natural allograft well tolerated by the maternal organism. Several factors contribute to maternal fetal tolerance: 1. The uterus is an immunologically privileged body site, protected by a non-immunogenic tissue barrier. 2. Promoting a local immunosuppressive response by the mother: a. The MHC class Ib HLA-G molecule, expressed on placental cells, prevents NK cells from killing the placenta; b. The catabolization of the essential amino acid tryptophan by the placenta prevents the mother's T cells from accessing the fetus; c. Secretion of TGF-ß, IL-4 and IL-10 cytokines by the uterine and trophoblast epithelium tends to suppress the T-cell responses of the mother; d. Secretion of TGF-ß and IL-10 cytokines by regulatory T cells also inhibits maternal T cell responses.(AU)

Frequência dos alelos do sistema antígeno leucocitário humano em doadores e pacientes pré-transplante de medula óssea / Human leukocyte antigen alleles frequency in donors and pre-transplant patients from bone marrow

Introdução: O estudo da frequência dos alelos detectados nos doadores e pacientes previamente selecionados para o transplante de medula óssea permite estimar as reais chances de um paciente em lista de espera encontrar um doador com antígeno leucocitário humano (Human leucocite antigen; HLA) idêntico não relacionado, além de facilitar e direcionar o planejamento do crescimento do Registro Nacional deDoadores de Medula Óssea. Objetivo: Descrever e analisar afrequência dos alelos do sistema HLA de classe I (HLA-A, -B e -C) e classe II (HLA-DRB1 e -DQB1) de doadores e pacientespré-transplante de medula óssea, do Hospital de Câncer deBarretos. Material e Métodos: Um total de 98 amostras dedoadores e 106 amostras de pacientes foi selecionado comtipificações em alta resolução, no período de outubro de 2014a outubro de 2015. As amostras foram tipificadas para os lociHLA-A, -B, -C, -DR e -DQ. Resultados: O predomínio daraça branca reflete a composição étnica do Brasil. As doençasde base mais comuns que levaram o paciente ao transplanteforam a leucemia aguda linfóide (34%) e mieloide (29,2%).Os grupos alélicos mais frequentes nos registros foramA*02, A*24, A*03, A*01, B*35, B*44, C*07, DQB1*03,DQB1*05, DQB1*06, DRB1*01 e DRB1*13. Conclusão: Osresultados encontrados reforçam a importância de conhecero perfil demográfico e imunogenético das regiões do Brasil,contribuindo desta forma na redução do tempo de espera porum doador histocompatível

Introduction: The study of allele frequencies detected in donors and patients previously selected for bone marrow transplantation allows us to estimate the real chances of a patient in the waiting list to find an Human leucocite antigen (HLA) identical unrelated donor. This also facilitates and drives the growth planning of the Brazilian Registry of planning Bone Marrow Transplantation (REDOME). Objective: Describe and analyze the frequency of HLA class I alleles (HLA-A*, -B* and ­C*) and class II alleles, genotypes, and haplotypes(HLA-DRB1* and -DQB1*) from donors and bone marrowpre-transplant patients. Material and Methods: A total of 98donor samples and 106 patient samples were selected withhigh resolution typing, from October 2014 to October 2015.Samples were typed for HLA-A, -B, -C, -DR and -DQ loci.Results: The predominance of the white race reflects theethnic composition of Brazil. The most common underlyingdiseases that led to transplantation patients were acutelymphoid leukemia (34%) and myeloid (29.2%). The mostfrequent allelic groups were A*02, A*24, A*03, A*01, B*35,B*44, C*07, DQB1*03, DQB1*05, DQB1*06, DRB1*01 andDRB1*13. Conclusion: The results reinforce the importanceof understanding the demographic and immunogenic profilefrom Brazilian Regions. This can contribute to the reduction ofwaiting time for a histocompatible donor.

Avaliação fenotípica e genotípica dos genes HLA LOCI (A*, B*, C*, DRB1* e DQB1*) dos doadores e pacientes pré-TMO do hospital de câncer de Barretos-SP / Phenotipic evaluation and genotypic genes HLA LOCI (A*, B*, C*, DRB1* and DQB1*) donor and patients in pre-BMT Barretos cancer hospital São Paulo state

Objetivo ­ Descrever e analisar a frequência dos alelos, genótipos e haplótipos HLA de classe I (HLA-A, -B e -C) e classe II (HLA-DRB1 e -DQB1) dos pacientes na fase pré-transplante de medula óssea, genotipados no laboratório de Imunogenética-HLA do Hospital de Câncer de Barretos. O estudo da frequência dos alelos detectados nos doadores e pacientes previamente selecionados para o transplante de medula óssea permite estimar as reais chances de um paciente em lista de espera encontrar um doador HLA idêntico não relacionado, além de facilitar e direcionar o planejamento do crescimento do Registro. Métodos ­ Os dados foram obtidos através da técnica de amplificação em cadeia de polimerase e para a genotipagem dos alelos dos genes A, B, C, DRB1 e DQB1 foi empregado o método de sequenciamento de nucleotídeos. Resultados ­ Entre outubro de 2014 a outubro de 2015 foram tratados 106 pacientes e 98 doadores de medula óssea cadastrados. As doenças de base mais comuns que levaram o paciente ao transplante foram as leucemias agudas linfóides (34%) e mielóides (29,2%). A caracterização imunogenética dos pacientes na fase pré-transplante de medula óssea mostrou um total de 19 alelos do loco A, 24 do loco B, 14 do loco C, 5 do loco DQ, 13 do loco DR; já nos dadores de medula óssea, 16 alelos do loco A, 25 do loco B, 13 do loco C, 5 do loco DQ e 12 do loco DR. Conclusão ­ Os grupos alélicos mais frequentes nos registros foram A*02, A*24, A*03, A*01, B*35, B*44, C*07, DQB1*03, DQB1*05, DQB1*06, DRB1*01 e DRB1*13. Apenas o conhecimento da frequência do tipo HLA específico do paciente na população não garante que ele encontre o doador compatível, é necessário também que o portador desse tipo HLA se encontre cadastrado no REDOME como doador voluntário.

Objective ­ Describe and analyze the frequency of the alleles, genotypes, and haplotypes HLA class I (HLA-A*, -B* and ­C*) and class II (HLA-DRB1* and -DQB1*) of patients in the bone marrow before transplantation phase genotyped in laboratory of ImmunogeneticsHLA Barretos Cancer Hospital. The study detected the frequency of alleles in patients and donors selected for bone marrow transplantation allows to estimate the real chances of a patient on the waiting list to find an unrelated HLA-identical donor, and to facilitate and direct the Brazilian Registry of planning Bone Marrow Transplantation (REDOME). Methods ­ The data were obtained by amplification using polymerase chain, and for genotyping the alleles of the genes A, B, C, DRB1 and DQB1 was employed nucleotide sequencing method. Results ­ From October 2014 to October 2015 were treated 106 patients and 98 donors registered bone marrow. The most common underlying diseases that led to transplantation patients were acute lymphoid leukemias (34%) and myeloid (29.2%). Immunogenetics characterization of patients in the bone marrow pre-transplant phase showed a total of 19 alleles at the A loci, 24 in B loci, 14in C loci, 5 in DQB1 loci and 13 in DRB1 loci; already in the bone marrow donors, 16 alleles at the A loci, 25 in B loci, 13 in C loci, 5 in DQB1 loci and 12 in DRB1 loci. Conclusion ­ The most frequent allelic groups were A*02, A*24, A*03, A*01, B*35, B*44, C*07, DQB1*03, DQB1*05, DQB1*06, DRB1*01 and DRB1*13. Knowledge of the frequency of HLA genes patients are not enough to find a compatible donor, it is necessary that the record contains the donor available

Avaliação da qualidade do sono em estudantes de Biomedicina / Sleep quality assessment in Biomedicine students

Objetivo ­ Avaliar a qualidade de sono e a sonolência diurna excessiva nos alunos de Biomedicina da Universidade Paulista ­ Sorocaba, comparando-as entre os alunos dos períodos diurno e noturno, além de identificar o cronotipo desses alunos. Métodos ­ Submeter 100 estudantes, de ambos os gêneros, com idade entre 18 e 52 anos, ao questionário de Qualidade de Sono de Pittsburgh (PSQI), à Escala de Sonolência de Epworth (ESE) e ao Questionário de Matutinidade/Vespertinidade. Resultados ­ Verificou-se que 61,5% dos alunos da manhã apresentaram má qualidade de sono, 51,3% sonolência diurna excessiva e 61,5% cronotipo indiferente; enquanto, 65,6% dos alunos da noite apresentavam má qualidade de sono, 57,4% sonolência diurna excessiva e 72,1% cronotipo indiferente. Conclusão ­ A má qualidade de sono foi mais frequente no período noturno, porém, mais relevante no período diurno. Ambos os períodos indicaram relevante prevalência de sonolência diurna excessiva, sem apresentar, contudo, uma preferência por um turno específico para realizarem suas atividades, o que foi observado por meio da maior frequência do cronotipo indiferente.

Objective ­ To evaluate the sleep quality and the presence of excessive daytime sleepiness in Biomedicine students from Universidade Paulista ­ Sorocaba; 2) to compare the results obtained from students enrolled in different periods of day or night; 3) to identify the best period of performance from these students. Methods ­ A hundred students from both genders, aged over 18 years, filled three questionnaires: Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS) and Questionnaire morningness/eveningness. Afterward, all the data was analyzed and presented accordingly. Results ­ It was found that 61.5% of the morning students presented poor sleep, 51.3% excessive daytime sleepiness, and 61.5% indifferent chronotype; while 65.6% of night's students presented poor sleep, 57.4% excessive daytime sleepiness, and 72.1% indifferent chronotype. Conclusions ­ Poor sleep was more frequent among night's students. In contrast, the worst quality of sleep was more relevant among morning's student. Students in both periods presented excessive daytime sleepiness and indifferent chronotype.

Tolerogenic Dendritic Cells Reduce Airway Inflammation in a Model of Dust Mite Triggered Allergic Inflammation

PURPOSE: The use of tolerogenic dendritic cells (TolDCs) to control exacerbated immune responses may be a prophylactic and therapeutic option for application in autoimmune and allergic conditions. The objective of this work was to evaluate the effects of TolDC administration in a mouse model of allergic airway inflammation caused by mite extract. METHODS: Mouse bone marrow-derived TolDCs were induced by incubation with granulocyte-macrophage colony-stimulating factor (GM-CSF) and dexamethasone, and then characterized by flow cytometry and cytokine production by enzyme-linked immunosorbent assay (ELISA). For the in vivo model of Blomia tropicalis-induced allergy, mice transplanted with antigen-pulsed TolDCs were sensitized intraperitoneally with B. tropicalis mite extract (BtE) adsorbed to aluminium hydroxide. After challenge by nasal administration of BtE, bronchoalveolar lavage fluid (BALF), lungs, spleen and serum were collected for analysis. RESULTS: Induction of TolDCs was efficiently achieved as shown by low expression of major histocompatibility complex (MHC) II, programmed death-ligand (PD-L) 2 and pro-inflammatory cytokine production, and up-regulation of interleukin (IL)-10, upon LPS stimulation in vitro. Transplantation of 1 or 2 doses of BtE-pulsed TolDCs reduced the number of inflammatory cells in BALF and lungs as well as mucus deposition. Moreover, compared to saline-injected controls, TolDC-treated mice showed lower serum levels of anti-BtE immunoglobulin E (IgE) antibodies as well as reduced Gata3 and IL-4 gene expression in the lungs and decreased IFN-γ levels in the supernatant of splenocyte cultures Transplantation of TolDCs increased the percentage of the regulatory T cells in the spleen and the lungs. CONCLUSIONS: Preventive treatment with TolDCs protects against dust mite-induced allergy in a mouse model, reinforcing the use of tolerogenic dendritic cells for the management of allergic conditions.

Ectopically Expressed Membrane-bound Form of IL-9 Exerts Immune-stimulatory Effect on CT26 Colon Carcinoma Cells

IL-9 is a known T cell growth factor with pleiotropic immunological functions, especially in parasite infection and colitis. However, its role in tumor growth is controversial. In this study, we generated tumor clones expressing the membrane-bound form of IL-9 (MB-IL-9) and investigated their influences on immune system. MB-IL-9 tumor clones showed reduced tumorigenicity but shortened survival accompanied with severe body weight loss in mice. MB-IL-9 expression on tumor cells had no effect on cell proliferation or major histocompatibility complex class I expression in vitro. MB-IL-9 tumor clones were effective in amplifying CD4⁺ and CD8⁺ T cells and increasing cytotoxic activity against CT26 cells in vivo. We also observed a prominent reduction in body weights and survival period of mice injected intraperitoneally with MB-IL-9 clones compared with control groups. Ratios of IL-17 to interferon (IFN)-γ in serum level and tumor mass were higher in mice implanted with MB-IL-9 tumor clones than those observed in mice implanted with control cells. These results indicate that the ectopic expression of the MB-IL-9 on tumor cells exerts an immune-stimulatory effect with toxicity. To exploit its benefits as a tumor vaccine, a strategy to control the toxicity of MB-IL-9 tumor clones should be developed.

Human Embryonic Stem Cell Derived from Early Stage Fertilized Ovum: Non Immunogenic and Universal, Neuronal and Non-neuronal Cell Lines

BACKGROUND: Human embryonic stem cells (hESCs) have the potential to treat various human disorders currently labeled as incurable and/or terminal illness. However, the fear that the patients' immune system would recognize them as non self and lead to an immune rejection has hampered their use. The main cause for immune rejection is usually the incompatibility of both donor and recipient's major histocompatibility complex (MHC). METHODS: We describe a hESC line developed through a patented technology that does not lead to immune reaction upon transplantation. We have transplanted these cells in >1,400 patients with chronic/terminal conditions and did not observe any immune reaction. No immunosuppressant were administered to these patients. We analyzed the expression levels of MHC-I and MHC-II on the surface of these hESCs using microarray technology. The gene targets for miRNA were analyzed using Gene ontology and DAVID database and pathways for these genes were determined using Reactome and Panther databases. RESULTS: Our results showed that the levels of expression of MHC-I and MHC-II on hESCs is almost negligible and thus the hESCs are less susceptible to an immune rejection. CONCLUSIONS: The hESCs cultured at our facility expresses low levels of MHC-I and do not produce an immune reaction. These can be administered universally and need no cross matching before transplantation.

Expansion and Sub-Classification of T Cell-Dependent Antibody Responses to Encompass the Role of Innate-Like T Cells in Antibody Responses

In addition to T cell-dependent (TD) Ab responses, T cells can also regulate T cell-independent (TI) B cell responses in the absence of a specific major histocompatibility complex (MHC) class II and antigenic peptide-based interaction between T and B cells. The elucidation of T cells capable of supporting TI Ab responses is important for understanding the cellular mechanism of different types of TI Ab responses. Natural killer T (NKT) cells represent 1 type of helper T cells involved in TI Ab responses and more candidate helper T cells responsible for TI Ab responses may also include γδ T cells and recently reported B-1 helper CD4⁺ T cells. Marginal zone (MZ) B and B-1 cells, 2 major innate-like B cell subsets considered to function independently of T cells, interact with innate-like T cells. Whereas MZ B and NKT cells interact mutually for a rapid response to blood-borne infection, peritoneal memory phenotype CD49d(high)CD4⁺ T cells support natural Ab secretion by B-1 cells. Here the role of innate-like T cells in the so-called TI Ab response is discussed. To accommodate the involvement of T cells in the TI Ab responses, we suggest an expanded classification of TD Ab responses that incorporate cognate and non-cognate B cell help by innate-like T cells.

Third-party regulatory T cells prevent murine acute graft-versus-host disease

BACKGROUND/AIMS: Adoptive therapy with regulatory T (Treg) cells to prevent graft-versus-host disease (GVHD) would benefit from a strategy to improve homing to the sites of inflammation following hematopoietic stem cell transplantation (HSCT). Although donor-derived Treg cells have mainly been used in these models, third-party-derived Treg cells are a promising alternative for cell-based immunotherapy, as they can be screened for pathogens and cell activity, and banked for GVHD prevention. In this study, we explored major histocompatibility complex (MHC) disparities between Treg cells and conventional T cells in HSCT to evaluate the impact of these different cell populations on the prevention of acute GVHD, as well as survival after allogeneic transplantation. METHODS: To induce acute GVHD, lethally irradiated BALB/c (H-2d) mice were transplanted with 5 × 10⁵ T cell-depleted bone marrow cells and 5 × 10⁵ CD4+CD25– splenic T cells from C57BL/6 (H-2b) mice. Recipients were injected with 5 × 10⁵ cultured donor-, host-, or third-party-derived CD4+CD25+CD62L+ Treg cells (bone marrow transplantation + day 1). RESULTS: Systemic infusion of three groups of Treg cell improved clinicopathological manifestations and survival in an acute GVHD model. Although donor-derived Treg cells were immunologically the most effective, the third-party-derived Treg cell therapy group displayed equal regulation of expansion of CD4+CD25+- Foxp3+ Treg cells and suppressive CD4+IL-17+ T-helper (Th17) cells in ex vivo assays compared with the donor- and host-derived groups. CONCLUSIONS: Our findings demonstrate that the use of third-party Treg cells is a viable alternative to donor-derived Treg cellular therapy in clinical settings, in which human leukocyte antigen-matched donors are not always readily available.

Clinical Impact of Pre-transplant Antibodies Against Angiotensin II Type I Receptor and Major Histocompatibility Complex Class I-Related Chain A in Kidney Transplant Patients

BACKGROUND: Evidence of antibody-mediated injury in the absence of donor-specific HLA antibodies (HLA-DSA) has recently emerged, suggesting a role of antibodies in targeting non-HLA antigens expressed on renal allograft tissue. However, the clinical significance of pre-transplant non-HLA antibodies remains unclear. We compared the histological and clinical impact of pre-transplant HLA-DSA and non-HLA antibodies, especially angiotensin II type I receptor (anti-AT1R) and MHC class I-related chain A (anti-MICA), in kidney transplant patients. METHODS: Pre-transplant HLA-DSA, anti-AT1R, and anti-MICA were retrospectively examined in 359 kidney transplant patients to determine the effect of each antibody on allograft survival and clinical characteristics. RESULTS: Pre-transplant HLA-DSA, anti-AT1R, and anti-MICA were detected in 37 (10.3%), 174 (48.5%), and 50 patients (13.9%), respectively. Post-transplant antibody-mediated rejection was associated with a pre-transplant HLA-DSA (+) status only. The development of microvascular inflammation (MVI) was associated with pre-transplant HLA-DSA (P=0.001) and anti-AT1R (P=0.036). Anti-AT1R (+) patients had significantly lower allograft survival compared with anti-AT1R (−) patients (P=0.042). Only pre-transplant anti-AT1R positivity was an independent risk factor for allograft failure (hazard ratio 4.824, confidence interval 1.017–24.888; P=0.038). MVI was the most common histological feature of allograft failure in patients with pre-transplant anti-AT1R. CONCLUSIONS: Pre-transplant anti-AT1R is an important risk factor for allograft failure, which may be mediated by MVI induction in the allograft tissue.

Extended Culture of Bone Marrow with Granulocyte Macrophage-Colony Stimulating Factor Generates Immunosuppressive Cells

Bone marrow-derived dendritic cells (BM-DCs) are generated from bone marrow (BM) cells cultured with granulocyte macrophage-colony stimulating factor (GM-CSF) for a week. In this study we investigated the effect of duration on the BM culture with GM-CSF. Within several months, the cells in the BM culture gradually expressed homogeneous levels of CD11c and major histocompatibility complex II on surface, and they became unable to stimulate allogeneic naïve T cells in mixed lymphocyte reaction (MLR). In addition, when the BM culture were sustained for 32 wk or longer, the BM cells acquired ability to suppress the proliferation of allogeneic T cells in MLR as well as the response of ovalbumin-specific OT-I transgenic T cells in antigen-dependent manner. We found that, except for programmed death-ligand 1, most cell surface molecules were expressed lower in the BM cells cultured with GM-CSF for the extended duration. These results indicate that BM cells in the extended culture with GM-CSF undergo 2 distinct steps of functional change; first, they lose the immunostimulatory capacity; and next, they gain the immunosuppressive ability.

The Role of B Cells in Transplantation Rejection / 대한이식학회지

B cells play a role in graft rejection via several mechanisms. Specifically, B cells produce high-affinity antibodies to alloantigens including allogeneic major histocompatibility complex (MHC) with the help of follicular helper T cells. B cells also function as antigen-presenting cells for alloreactive T cells, resulting in the activation of alloreactive T cells. Conversely, the frequency of regulatory B cells increases under inflammatory conditions and suppresses the rejection process. Here, the differential roles of the major B cell subpopulations (B-1, follicular B, marginal zone B, and regulatory B cells) involved in transplantation rejection are discussed together with their interaction with T cells.

A Salmonella Typhi ghost induced by the E gene of phage φX174 stimulates dendritic cells and efficiently activates the adaptive immune response

Previously, we genetically engineered a Salmonella Typhi bacterial ghost (STG) as a novel inactivated vaccine candidate against typhoid fever. The underlying mechanism employed by the ghost in stimulating the adaptive immune response remains to be investigated. In this study, we aimed to evaluate the immunostimulatory effect of STG on mouse bone marrow-derived dendritic cells (BMDCs) and its activation of the adaptive immune response in vitro. Immature BMDCs were stimulated with STG, which efficiently stimulated maturation events in BMDCs, as indicated by upregulated expressions of CD40, CD80, and major histocompatibility complex class II molecules on CD11⁺ BMDCs. Immature BMDCs responded to STG stimulation by significantly increasing the expression of interleukin (IL)-6, which might indicate the induction of dendritic cell maturation in vivo (p < 0.05). In addition, ghost-stimulated murine BMDCs showed significant expressions of interferon gamma and IL-4, which can drive the development of Th1 and Th2 cells, respectively, in co-cultured CD4⁺ T cells in vitro. These results suggest that STG can effectively stimulate maturation of BMDCs and facilitate subsequent immune responses via potent immunomodulatory cytokine responses.

Saprolegnia parasitica Isolated from Rainbow Trout in Korea: Characterization, Anti-Saprolegnia Activity and Host Pathogen Interaction in Zebrafish Disease Model

Saprolegniasis is one of the most devastating oomycete diseases in freshwater fish which is caused by species in the genus Saprolegnia including Saprolegnia parasitica. In this study, we isolated the strain of S. parasitica from diseased rainbow trout in Korea. Morphological and molecular based identification confirmed that isolated oomycete belongs to the member of S. parasitica, supported by its typical features including cotton-like mycelium, zoospores and phylogenetic analysis with internal transcribed spacer region. Pathogenicity of isolated S. parasitica was developed in embryo, juvenile, and adult zebrafish as a disease model. Host-pathogen interaction in adult zebrafish was investigated at transcriptional level. Upon infection with S. parasitica, pathogen/antigen recognition and signaling (TLR2, TLR4b, TLR5b, NOD1, and major histocompatibility complex class I), pro/anti-inflammatory cytokines (interleukin [IL]-1β, tumor necrosis factor α, IL-6, IL-8, interferon γ, IL-12, and IL-10), matrix metalloproteinase (MMP9 and MMP13), cell surface molecules (CD8⁺ and CD4⁺) and antioxidant enzymes (superoxide dismutase, catalase) related genes were differentially modulated at 3- and 12-hr post infection. As an anti-Saprolegnia agent, plant based lawsone was applied to investigate on the susceptibility of S. parasitica showing the minimum inhibitory concentration and percentage inhibition of radial growth as 200 μg/mL and 31.8%, respectively. Moreover, natural lawsone changed the membrane permeability of S. parasitica mycelium and caused irreversible damage and disintegration to the cellular membranes of S. parasitica. Transcriptional responses of the genes of S. parasitica mycelium exposed to lawsone were altered, indicating that lawsone could be a potential anti-S. parasitica agent for controlling S. parasitica infection.