Conventional IgG is composed of heavy and light chains. The light chain has one variable region (VL) and one constant region (CL) domain, whereas the heavy chain has one variable region (VH) and three constant region domains (CH1, CH2 and CH3). Single domain antibody (sdAb) is a kind of antibody that is composed of a variable domain of heavy chain and devoid of the light chain completely. Due to its small size, it is also called as nanobody. Although the sdAb has a simple structure, it can exhibit a comparable even better antigen-binding affinity than conventional antibody. Compared with conventional antibody, the small size, high stability and simplicity in recombinant expression are representative advantages of sdAb. In recent years, scientists are becoming increasingly interested in the roles of sdAb in fundamental biomedical research and clinical application. In this review, we summarized the structural features, physicochemical properties, screening strategies and recent advances in application of sdAb.
Antibodies ; immunology

Antibodies, Antineutrophil Cytoplasmic ; immunology ; Glomerulonephritis ; immunology ; Humans

Immune factors account for 5%-15% of male infertility. Because of the diversity in molecular weight, structure and location, sperm antigens play different roles in immune infertility. Antisperm antibodies (AsAb) influence sperm function not only by direct action, but also by changing the local microenvironment indirectly. This paper reviews the progress in the studies of the implication of human sperm antigens, the function, mechanisms, categories and titer of AsAb in male infertility.
Antibodies ; immunology ; Humans ; Immunoglobulin Isotypes ; immunology ; Male ; Reproduction ; Spermatozoa ; immunology

PURPOSE: House dust mites (HDMs) are an important source of indoor allergens associated with asthma, rhinitis and atopic dermatitis. Chicken immunoglobulin (Ig) Y is known to be a good alternative to mice and rabbit antibody production. In this study, we produced IgYs specific to HDMs and investigated their IgE immunoreactivities. MATERIALS AND METHODS: Total IgYs were isolated from the yolks of White Leghorn hens immunized with either Dermatophagoides pteronyssinus or D. farinae protein extract. Control antibodies were separated from the yolks of immunized hens with phosphate buffered saline. IgYs specific to HDMs were analyzed using enzyme-linked immunosorbent assay and Western blotting analysis. RESULTS: The concentration of egg IgY specific to D. farinae in an immunized hen increased and the highest achieved was 661.3 ug/mg (per an egg) on day 47, compared with 760 ug/mg IgY specific to D. pteronyssinus on day 16. The D. pteronyssinus or D. farinae-specific IgY was detected by binding of each mite proteins, and their immunoreactivities were elevated dependent of the specific IgY concentration. CONCLUSION: IgY specific to HDMs may be a promising antibody for immunological diagnosis as well as identification of possible resistance relating to HDM allergy.
Allergens/*immunology ; Animals ; Antibodies/*immunology ; Chickens ; Egg Yolk/*immunology ; Female ; Immunoglobulins/*immunology ; Pyroglyphidae/*immunology

A human immunodeficiency virus type-1 (HIV-1) vaccine which is able to effectively prevent infection would be the most powerful method of extinguishing pandemic of the acquired immunodeficiency syndrome (AIDS). Yet, achieving such vaccine remains great challenges. The membrane-proximal external region (MPER) is a highly conserved region of the envelope glycoprotein (Env) gp41 subunit near the viral envelope surface, and it plays a key role in membrane fusion. It is also the target of some reported broadly neutralizing antibodies (bNAbs). Thus, MPER is deemed to be one of the most attractive vaccine targets. However, no one can induce these bNAbs by immunization with immunogens containing the MPER sequence(s). The few attempts at developing a vaccine have only resulted in the induction of neutralizing antibodies with quite low potency and limited breadth. Thus far, vaccine failure can be attributed to various characteristics of MPER, such as those involving structure and immunology; therefore, we will focus on these and review the recent progress in the field from the following perspectives: (1) MPER structure and its role in membrane fusion, (2) the epitopes and neutralization mechanisms of MPER-specific bNAbs, as well as the limitations in eliciting neutralizing antibodies, and (3) different strategies for MPER vaccine design and current harvests.
AIDS Vaccines ; chemistry ; immunology ; Antibodies, Neutralizing ; immunology ; HIV Antibodies ; immunology ; HIV Envelope Protein gp41 ; immunology ; HIV-1 ; chemistry ; immunology ; Humans

The polyclonal antibodies against VLDL receptor were prepared and identified. Rabbits were immunized with polypeptide fragment of VLDL receptor as antigen. The collected blood serum of the immunized rabbits was analyzed and identified by using ELISA and Western Blot. The results showed that the rabbit against mouse and human VLDL receptor antibodies were obtained with high titer and could recognize the natural VLDL receptors through Western blot. The prepared polyclonal antibodies against VLDL receptor provide a new tool to study the protein of VLDL receptor.
Antibodies/chemistry ; Antibodies/*immunology ; Enzyme-Linked Immunosorbent Assay ; Peptides/*immunology ; Receptors, LDL/*immunology

Adult ; Alternaria ; immunology ; Alveolitis, Extrinsic Allergic ; immunology ; Animals ; Antibodies ; immunology ; Antibodies, Bacterial ; immunology ; Antibodies, Fungal ; immunology ; Antigens ; immunology ; Antigens, Bacterial ; immunology ; Antigens, Fungal ; immunology ; Aspergillus fumigatus ; immunology ; Asymptomatic Diseases ; Candida albicans ; immunology ; Cladosporium ; immunology ; Columbidae ; immunology ; Female ; Healthy Volunteers ; Humans ; Immunoglobulin G ; immunology ; Male ; Melopsittacus ; immunology ; Middle Aged ; Mucor ; immunology ; Nocardia ; immunology ; Parrots ; immunology ; Penicillium chrysogenum ; immunology ; Stachybotrys ; immunology ; Thermoactinomyces ; immunology

The platelet antibodies mainly include platelet-specific and related antibodies, which belong to irregular antibodies. They are produced by autoimmune, drug-induced or isoimmunization (such as pregnancy, blood transfusion and so on), the irregular IgG and/or IgM antibodies produce and lead to platelet transfusion refractoriness (PTR), post-transfusion purpura (PTP) and isoimmune neonatal thrombocytopenic purpura (INTP), idiopathic thrombocytopenic purpura and so on. It is very necessary to screen and identify the irregular antibodies before blood transfusion or parturition. Except some serological detections should be done first, flow cytometry and molecular biological techniques such as PCR and PCR-SSP are applied to detect the difficult-matching patients' genotypes and fetal genotypes in order to further predict fetal INTP and to provide the right blood for difficult-matching patients, therefore, some measures must be taken early for prevention and treatment of immune thrombocytopenic purpura. In this review, the production, typing and laboratory tests of irregular antibodies, as well as the pathogenesis and clinical symptoms of diseases caused by irregular antibodies, and the current progress are summarized.
Antibodies ; immunology ; Humans ; Purpura, Thrombocytopenic, Idiopathic ; etiology ; immunology

Animals ; Antibodies, Monoclonal ; immunology ; Humans ; Receptors, Interleukin-17 ; immunology

OBJECTIVETo characterize the specific monoclonal antibodies to Aspergillus conidia.

METHODSFlow cytometry was used to examine the reactivity of the specific monoclonal antibodies to Aspergillus conidia.

RESULTSBoth the monoclonal antibodies MA3 and Con2 showed specific reactivity to Aspergillus conidia suspensions. MA3 was capable of binding to the conidia of A.fumigatus, A.flavus, A.niger and A.terreus, while Con2 was reactive only to the conidia of A.fumigatus.

CONCLUSIONTwo specific monoclonal antibodies (MA3 and Con2) to Aspergillus conidia have been obtained.

Antibodies, Fungal ; immunology ; isolation & purification ; Antibodies, Monoclonal ; immunology ; isolation & purification ; Antibody Specificity ; Aspergillus ; immunology ; Flow Cytometry ; Spores, Fungal ; immunology