Immunity hyperimmunity

Passive immunity can be provided by equine botulinum antitoxin or by specific human hyperimmune globulin, while endogenous immunity can be induced by immunization with botulinum toxoid... 

Antibody Preparation and Characterization. Our best [STX0L]n-BSA immunogen (n=9) was used to hyperimmunize a total of 6 rabbits. The formation of anti-STXOL antibodies was monitored by determining the quantity of specific binding protein (presumably IgG) in the serum samples. Table I shows that 5 of the 6 rabbits produced anti-STXOL antibodies within 100 days after initial immunization. 

Antithymocyte globulin (Atgam) is purified immune globulin obtained from hyperimmune serum of horses... 

Immune globulin is isolated from pooled human plasma either from donors in the general population or from hyperimmunized donors. It is used principally in the... 

The usual dose of Rho(D) immune globulin is 2 mL intramuscularly, containing approximately 300 meg anti-Rh0(D) IgG. Adverse reactions are infrequent and consist of local discomfort at the injection site or, rarely, a slight temperature elevation. Hyperimmune Immunoglobulins... 

Class Immunosuppressant gamma globulin, primarily monomeric IgG, from hyperimmune serum of horses immunized with human thymic lymphocytes... 

Whereas IgG is the most abundant antibody in the hyperimmunized host, in the newly immunized animal, IgM is the first humoral antibody detectable. The primary antibody formation proceeds in several major stages. Injected immunogen first reaches equilibrium between extra-and intravascular spaces, then undergoes catabolism resulting in smaller fragments, and finally is eliminated from the intravascular spaces by the newly formed antibodies. The period from the introduction of an immunogen until the first appearance of humoral IgM antibodies is called the latent period and may last approximately one week. Within two weeks, or in response to a second injection, IgG class antibodies usually predominate. Like all proteins, antibodies are subject to catabolism. Whereas antibodies of class IgM have a relatively short half-life of only four to six days, IgG antibodies have a mean survival of approximately three weeks. Unless repeated booster... 

Hyperimmunization The practice of establishing a heightened state of the actively acquired immunity by the administration of repeated doses of antigen. 

A recent presentation by an FDA reviewer noted that for a number of immune globulin products surveyed, no preclinical animal studies were presented in the INDs [14], The immune globulins surveyed included immune globulin (intravenous), as well as hyperimmune globulins both intravenous and intramuscular forms. This situation is likely due to the long history of these products and the similarities in their manufacturing. 

Originally antibodies were obtained by injecting an antigen to an animal to induce an immune response leading to the secretion of specific antibody molecules. This is still an important method for generating antibodies. When antibodies are intentionally induced in humans by vaccination and the blood is collected from volunteer donors, then these sera are called hyperimmune sera. 

The immunoglobulin fraction derived from the polyclonal hyperimmune serum of humans and animals has been used clinically in combating conditions such as bacterial infections and maternal immunization by Rh-positive cells from the fetus. Polyclonal sera raised against proteins have also been valuable diagnostic and research tools. However, the undefined composition of polyclonal antisera results in wide and unpredictable cross-reactivities. Furthermore, the quantities of antibody available are limited to the amount of serum an immunized animal can yield. Monoclonal antibodies described below circumvent these problems of definition and quantity associated with polyclonal sera. 

A merging of chemistry and biology is essential to effectively probe the immune system for catalytic antibodies (Fig. 3). Haptens that are successful in eliciting catalytic antibodies are variations of the central theme that transition state stabilization in the antibody combining site will yield functional catalysts for a desired chemical reaction. The evolution of hapten design will be discussed further in subsequent sections. Once the hapten is selected and synthesized, it is attached to an immunogenic carrier protein, usually via an amide bond, for hyperimmunization. A preliminary screen for antibodies that bind the hapten using an enzyme-linked immunosorbent assay (ELISA) is followed by another screen for catalysis of the reaction for which the hapten... 

The risk of postvaccinial encephalomyelitis is reduced by simultaneous administration of hyperimmune Vaccinia gamma globulin (32) or by pre-immunization with an antigen from formol-inactivated Vaccinia virus (34,35). However, cases of postvaccinial encephalomyelitis have been described even after these procedures (32,36). 

Plasma has been used extensively in horses with colitis and in neonatal foals for the passive transfer of immunity (Table 17.12). Plasma may either be purchased commercially or collected from donors and can be used fresh or stored frozen. Commercial plasma may be from donors who are hyperimmunized with certain equine pathogens and thus will contain antibodies to these pathogens. Hyperimmunized plasma may be preferable for the passive transfer of immunity... 

Anit-Maduramicin Antibody Production. New Zealand white rabbits were hyperimmunized with maduramicin-BSA in Freund s complete adjuvant and boosted biweekly with Freund s incomplete adjuvant four weeks after the initial immunization. Weekly bleeds were performed. Serum titre was monitored by indirect enzyme immunoassay described below. The antibody was produced through a contract with Hazleton Laboratory (Vienna, Virginia). 

These RF are often heterogeneous, but may become virtually monoclonal after a prolonged illness. It is not uncommon to find RF in hyperimmune sera. Their role is not clear, but they may clear the plasma of circulating immune complexes. 

TIG is a sterile, concentrated, nonpyrogenic solution of immunoglobulins prepared from hyperimmunized humans. It is used to provide passive immunity to tetanus following the occurrence of traumatic wounds in nonimmunized or suboptimally immunized persons (see Table 122-2). A dose of 250-500 units IM should be... 

A second procedure to reduce 1-ASP immunogenicity has been described by Uren and Ragin [33]. They used poly-DL-alanyl peptides to block immunogenic epitopes within the 1-ASP molecule derived from both E. coli and Erwinia. Similar to the PEGylated enzyme, the half-life in mice was markedly prolonged compared to the native enzymes even if the animals had previously been immunized with the latter preparation. Hyperimmune animals, however, rapidly cleared both the native and modified enzymes. Clinical studies have not been performed to date. 

Compared to monoclonal antibodies polyclonal antisera takes less time, effort and technical skill to produce. The serum from immunized animals contains antibodies with specificity to many different antigens or even to different antigenic groups (epitopes) in the antigen molecule. Even after hyperimmunization only a small fraction (usually a few percent) of the total IgG binds to the immunizing antigen. The variability in the response of the immunized animal accounts for differences in the binding... 

Hepatitis B virus (HBV) is widespread throughout human populations, specially in Asia and Africa, and it has been estimated that over 200 million carriers exist, some of whom are eventually expected to develop liver carcinoma or cirrhosis. HBV shows a strict tropism for liver hepatocytes in which it displays a protected replication with resultant foci of liver necrosis. The virus is a member of the Hepadnaviridae, along with several other species, and it replicates by a mechanism which appears to be unique to this family. In contrast, hepatitis A virus is a picornavirus and the hepatitis D agent appears to be a viroid-like RNA enclosed within a hepatitis B capsid, and consequently depends upon its association with the HBV for its spread and survival. Control may be effected by passive immunization (with hyperimmune globulin) or by various types of vaccines which are currently being developed and improved. Specific chemotherapy has not been consistently successful, but in some countries (e g., India and China), plant extracts have provided some success. 

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