Chitin, the second most abundant polysaccharide in nature after cellulose, consist exoskeleton of lower organisms such as fungi, crustaceans and insects except mammals. Recently, several studies evaluated immunologic effects of chitin in vivo and in vitro and revealed new aspects of chitin regulation of innate and adaptive immune responses. It has been shown that exogenous chitin activates macrophages and other innate immune cells and also modulates adaptive type 2 allergic inflammation. These studies further demonstrate that chitin stimulate macrophages by interacting with different cell surface receptors such as macrophage mannose receptor, toll-like receptor 2 (TLR-2), C-type lectin receptor Dectin-1, and leukotriene B4 recepptor (BLT1). On the other hand, a number of chitinase or chitinase-like proteins (C/CLP) are ubiquitously expressed in the airways and intestinal tracts from insects to mammals. In general, these chitinase family proteins confer protective functions to the host against exogenous chitin-containing pathogens. However, substantial body of recent studies also set light on new roles of C/CLP in the development and progression of allergic inflammation and tissue remodeling. In this review, recent findings on the role of chitin and C/CLP in allergic inflammation and tissue remodeling will be highlighted and controversial and unsolved issues in this field of studies will be discussed.
Animals ; Chitin/*immunology ; Chitinase/*immunology ; Glycoproteins/*immunology ; Humans ; Hypersensitivity/*immunology ; Inflammation/*immunology

Immune thrombocytopenia (ITP) is an autoimmune hemorrhagic disease. It is considered that production of platelet auto-antibodies was one of the pathogenesis of ITP, first-line therapy including corticosteroid and immunoglobulin could reduce destruction of platelets by inhibiting production of auto-antibodies and blocking Fc-receptor of reticuloendothelial system, but some of the patients were refractory to first-line therapy and have persistent duration of the disease, having worse prognosis and developing into chronic/refractory ITP(C/RITP) . Platelet membrane glycoprotein like GPIIb/IIIa and GPIbα are the most common antigen targets, but first-line therapy was less effective to patients whose anti-GPIbα antibodies are positive. Further studies revealed that the way causing platelet destruction by anti-GPIIb/IIIa antibodies and anti-GPIbα antibodies are different: the former is mainly dependent to Fc-pathway, and the latter mainly cleared platelet by Fc-independent way. Results above indicated that detection of type of platelet auto-antibodies maybe potential to treatment and prognosis of ITP. This article summarizes relationship between platelet specific antibodies and the onset, clinical manifestation, treatment and prognosis of ITP.
Antibodies ; immunology ; Autoimmune Diseases ; Blood Platelets ; immunology ; Humans ; Platelet Membrane Glycoproteins ; Prognosis ; Thrombocytopenia ; immunology ; therapy

In protection against microbes, an organism recognizes the pathogen associated molecular pattern (PAMP) on microbes by pattern recognition receptor (PRR). Toll-like receptor is called innate immunity. A family of cell membrane receptor was found in recent years that can mediate innate immune responses through the activation of a series of immune-related genes. In phylogenesis, it is highly conservative. However, its functions are getting more diversified with the complication of the immune functions of organisms.
Animals ; Humans ; Immunity ; Membrane Glycoproteins ; immunology ; Phylogeny ; Receptors, Cell Surface ; immunology ; Toll-Like Receptors

Influenza, caused by influenza virus, is a serious respiratory illness which poses a global public health threat. Vaccination is the primary strategy for the prevention and control of influenza. Although both inactivated vaccines and the live attenuated vaccines are effective in preventing influenza, the current vaccines have poor efficacy in the elderly and fail to provide protection against heterosubtype viruses. Development of a safer and more effective influenza vaccine that provides broad cross protection, overcoming the intrinsic limitation of the current vaccines, has been a scientific challenge. During the past decades, structural biology, reverse genetic and other virological technologies developed quickly and sped the progress of influenza vaccinology. Some new strategies for developing influenza vaccine have been generated, produced encouraging results, which showed great prospect as next-generation of influenza vaccines.
Disease Outbreaks ; prevention & control ; Hemagglutinin Glycoproteins, Influenza Virus ; immunology ; Humans ; Influenza Vaccines ; biosynthesis ; immunology ; Influenza, Human ; immunology ; prevention & control ; virology ; Orthomyxoviridae ; immunology ; Vaccines, Attenuated ; immunology ; Vaccines, Inactivated ; immunology

As a member of the HSP90 family, heat shock protein (HSP) Gp96 is one of the most abundant proteins in the endoplasmic reticulum (ER), which displayed important molecular chaperones function in cells. Gp96 can stimulate the production of cytokines by activating the antigen presentation cells (such as dendritic cell, et al) in innate immunity. It is capable of eliciting an antigen-specific cytotoxic T lymphocyte (CTL) immune response to eliminate pathogens and tumors by facilitating antigen cross-presentation in adaptive immunity. Gp96 is also an ideal adjuvant in many recent researches. Here, we review the progress that addresses the role of biological characteristics, immunogenic mechanism that may be involved in the induction of anti-infection immune response and antitumor immunity, which may guide the new vaccine strategies with the knowledge of Gp96-antigen complexes.
Adjuvants, Immunologic ; genetics ; metabolism ; Antigen-Presenting Cells ; physiology ; Communicable Diseases ; immunology ; Dendritic Cells ; immunology ; Endoplasmic Reticulum ; immunology ; Humans ; Membrane Glycoproteins ; immunology ; Neoplasms ; immunology ; T-Lymphocytes, Cytotoxic ; immunology

OBJECTIVETo measure the subsets of dendritic cells 1 (DC1) in the bone marrow of severe aplastic anemia (SAA) patients and evaluate the relationships between the CD11c+CD83+ cells and Th1 cells, CD3+CD8+ cells or hematopoietic function and explore the role of DC1 in the pathogenesis of SAA.

METHODSBy FACS, the quantities and ratios of CD11c+CD1a+ cells, CD11c+CD83+ cells, Th1 cells, and CD3+CD8+ cells in the bone marrow of SAA patients and normal controls were detected respectively. The relationships between CD3+CD8+ cells and reticulocyte absolute value (Ret) or neutrophil absolute value (ANC), between Th1 cells and CD3+CD8+ cells, Ret or ANC, between CD11c+CD83+ cells, and Th1 cells, CD3+CD8+ cells, Ret or ANC were evaluated.

RESULTSIn normal controls' bone marrow, the percentages of Th1 cells, CD11c+CD1a+ cells, CD11c+CD83+ cells and the ratio of CD11c+CD83+/CD11c+CD1a+ were (0.42 +/- 0.30)%, (0.38 +/- 0.29)%, (0.37 +/- 0.32)% and 1.07 +/- 0.10, respectively. In untreated SAA patients, they were (4.87 +/- 0.54)%, (1.73 +/- 0.24)%, (3.38 +/- 0.56)% and 2.21 +/- 0.32 respectively, which were higher than that in normal controls (P < 0.01). In recovering SAA patients, the percentages of Th1 cells, CD11c+CD1a+ cells and CD11c+CD83+ cells decreased significantly to (0.53 +/- 0.22)%, (0.61 +/- 0.23)%, (0.65 +/- 0.22)%, respectively (P < 0.01). The ratio of CD11c+CD83+/CD11c+ CD1a+ in recovering SAA patients decreased to 1.37 +/- 0.25, which was similar to that in normal controls (P > 0.05). The percentage of CD3+CD8+ cells in untreated SAA patients was (32.32 +/- 10.22)%, and in recovering SAA patients decreased to (13.67 +/- 5.24)% (P < 0.01). The percentage of CD3+CD8+ cells in SAA patients was negatively correlated with their Ret and ANC (P < 0.05), while their Th1 cell percentages were positively correlated with their CD3+CD8+ cells (P < 0.01), and negatively correlated with their Ret and ANC (P < 0.01). SAA patient's CD11c+CD83+ cell percentages were positively correlated with their Th1 cell and CD3+CD8 cells (P < 0.01, P < 0.05), but negatively with their Ret and ANC (P < 0.01).

CONCLUSIONBoth immature DC1 and activated DC1 increased in the bone marrow of SAA patients, and the balance of DC1 subsets shifted from stable form to active one, which might promote Th0 cells to polarize to Th1 cells, and cause the over-function of T lymphocytes and hematopoiesis failure in SAA.

Adolescent ; Adult ; Anemia, Aplastic ; immunology ; Antigens, CD ; immunology ; Antigens, CD1 ; immunology ; Bone Marrow ; immunology ; CD11c Antigen ; immunology ; CD8-Positive T-Lymphocytes ; immunology ; Child ; Dendritic Cells ; immunology ; Female ; Humans ; Immunoglobulins ; immunology ; Male ; Membrane Glycoproteins ; immunology ; Th1 Cells ; immunology ; Young Adult

Cytotoxic T cell (CTL) covers several subtypes, which are CD8+, CD4 and CD4-CD8-. CTL derives from T cell repertoire in lymphoid hematopoietic stem cells. It matures in thymus and is activated in peripheral lymphoid tissues. Effector CTL kills the target cells by 2 ways. One is apoptotic effect mediated by FasL-Fas pathway and the other one is cytolytic effect mediated by granzymes. CTL has aroused great attention due to its significance in anti-tumor and anti-virus.
Animals ; Fas Ligand Protein ; Humans ; Membrane Glycoproteins ; immunology ; Perforin ; Pore Forming Cytotoxic Proteins ; T-Lymphocytes, Cytotoxic ; immunology ; fas Receptor ; immunology

Heat shock protein gp96 is a highly conserved and monomorphic glycoprotein in the endoplasmic reticulum. It functions as molecular chaperone and can associate with a variety of antigenic peptides noncovalently in vivo and in vitro. Recent studies have indicated that gp96 molecules participate in major histocompatibility complex class I-restricted antigen presentation pathway. Immunization of mice with gp96 preparations isolated from cancer cells can elicit a cancer-specific protective T cell immune response that is recallable, which is a prerequisite for gp96 as a therapeutic vaccine against cancers. The immunogenicity of gp96 molecules has been attributed to the antigenic peptides associated with them. These phenomena provide a new pathway for cancer immunotherapy. The mechanism that the gp96-peptide complex induces specific immune response and the explorations for gp96-peptide complex as a therapeutic cancer vaccine are reviewed.
Animals ; Antigens, Neoplasm ; immunology ; therapeutic use ; Cancer Vaccines ; therapeutic use ; Humans ; Immunotherapy ; Membrane Glycoproteins ; immunology ; metabolism ; Molecular Chaperones ; immunology ; Neoplasms ; immunology ; therapy ; Peptides ; immunology ; metabolism

Objective To develop neutralizing monoclonal antibodies (MAbs) against H10N8 avian influenza virus hemagglutinin and to identify the binding sites. Methods MAbs against hemagglutinin of H10N8 avian influenza virus were developed by genetic engineering. Neutralizing MAbs were screened by microneutralization assay,and then tested by enzyme-linked immunosorbent assay and Western blot to identity the binding sites.The homology modeling process was performed using Discovery Studio 3.5 software,while the binding epitopes were analyzed by BioEdit software. Results One MAb that could neutralize the H10N8 pseudovirus was obtained and characterized. Analysis about epitopes suggested that the antibody could bind to the HA1 region of hemagglutinin,while the epitopes on antigen were conserved in H10 subtypes.Conclusions One neutralizing antibody was obtained by this research.The MAb may potentially be further developed as a pre-clinical candidate to treat avian influenza H10N8 virus infection.
Antibodies, Monoclonal ; immunology ; Antibodies, Neutralizing ; immunology ; Antibodies, Viral ; immunology ; Enzyme-Linked Immunosorbent Assay ; Epitopes ; immunology ; Hemagglutinin Glycoproteins, Influenza Virus ; immunology ; Influenza A Virus, H10N8 Subtype ; Neutralization Tests

Granzyme is an effector molecule of activated cytotoxic T cells and natural killer cells. It mainly mediates cell apoptosis. Its function could be explained by its molecular characteristics to some extent. Its cytotoxic effect is related to some other factors contributing to apoptosis induction. It deserves studying if perforin mediates entrance of granzyme into cells. As potential substrates of granzyme caspases and their substrates have been paid much attention to.
Animals ; Apoptosis ; Caspases ; immunology ; Granzymes ; Humans ; Killer Cells, Natural ; immunology ; Membrane Glycoproteins ; immunology ; Perforin ; Pore Forming Cytotoxic Proteins ; Serine Endopeptidases ; immunology ; T-Lymphocytes, Cytotoxic ; immunology