No abstract available.
Allergy and Immunology*

No abstract available.
Allergy and Immunology*

No abstract available.
Allergy and Immunology*

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

Asthma ; immunology ; Humans ; Rhinitis ; immunology

Hepatocytes ; immunology ; Liver Transplantation ; 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

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

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

OBJECTIVETo review the senescent remodeling of the immune system with aging and its relevance to the increased susceptibility of the elderly to infectious diseases, along with an outlook on emerging immunological biomarkers.

DATA SOURCESThe data selected were from PubMed with relevant published articles in English or French from 1995 to the present. Searches were made using the terms "immunosenescence" and "aging" paired with the following: "innate immunity", "T-cell", "B-cell", "adaptive immunity" and "biomarkers". Articles were reviewed for additional citations and some information was gathered from web searches.

STUDY SELECTIONArticles on aging of both the innate and adaptive immunity were reviewed, with special attention to the remodeling effect on the ability of the immune system to fight infectious diseases. Articles related to biomarkers of immunosenescence were selected with the goal of identifying immunological biomarkers predisposing the elderly to infections.

RESULTSInnate immunity is generally thought to be relatively well preserved or enhanced during aging compared with adaptive immunity which manifests more profound alterations. However, evidence, particularly in the last decade, reveals that both limbs of the immune system undergo profound remodeling with aging. Reported data on adaptive immunity is consistent and changes are well established but conflicting results about innate immunity were reported between in vivo and in vitro studies, as well as between murine and human studies. Epidemiological data suggests increased predisposition of the elderly to infections, but no compelling scientific evidence has directly linked senescent immune remodeling to this increased susceptibility. Recently, growing interest in identifying immunological biomarkers and defining "immune risk phenotypes/profiles" (IRP) has been expressed. Identification of biomarkers is in its early days and few potential biomarkers have been identified, with the Swedish having defined one IRP based on the adaptive immune response.

CONCLUSIONSAging does not necessarily lead to an unavoidable decline in immune functions. Instead, a complex remodeling occurs. Despite the lack of compelling scientific evidence, senescent immune remodeling surely is a significant contributing factor to the increased risk and severity of infections in the elderly. Although, no immunological biomarker has been formally linked to the increased risk of infections in the elderly, biomarkers remain a promising tool to predict the likelihood of healthy aging, the level of immune competence, and mortality risk in the elderly. Hence, more research is required to define healthy aging and identify immunological biomarkers.

Adaptive Immunity ; immunology ; Aging ; immunology ; physiology ; Animals ; Humans ; Immune System ; immunology ; Immunity, Innate ; immunology ; Infection ; immunology