Richard M. Hyde

Review of Immunology

Immunity (resistance to, or assistance with, an infectious disease) can be acquired by various means which are summarized below.

Immunofluorescence examination of typical Staphylococcus aureus variants and L-forms for clumping factor.

SUMMARY: Encapsulated coagulase-positive staphylococci which do not clump with fibrinogen possess the clumping factor antigen as well as other cell-wall antigens characteristic of Staphylococcus aureus. Variants which were negative for both coagulase and clumping factor not only lacked the clumping factor antigen but also other S. aureus surface antigens. L-forms did not remove clumping inhibiting antibody from S. aureus antisera. Antisera which were relatively high in clumping-inhibiting antibodies, but low in agglutinins, gave no fluorescence with coagulase-negative, clumping factor-negative variants or L-forms. The clumping factor, probably a cell-wall component of S. aureus, is absent in the penicillin-induced, stable L-form.

Antiserum Production in Experimental Animals

Publisher Summary This chapter discusses certain aspects of immunization practices, which will help in producing specific antiserum to substances of biological interest. Many practical considerations must be evaluated in the selection of the animal to be used as the source of antiserum—for example, the amount of antiserum desired, the ease of bleeding the animal, and the cost of purchase and maintenance of the animal. Antigens must be kept out of the circulation of the experimental animal. In general, the greater the phylogenetic disparity of the antigen and the experimental animal, the greater will be the immune response the antigen induces. Because of the variation in antibody response seen in experimental animals, at least two precautions should be taken when establishing an immunization schedule. First, sufficient numbers of animals should be used to assure that even if the proportion of animals producing antibody is low, some of them will produce the antibody desired. Second, periodic bleedings should be done during the immunization period and the serum should be examined for the presence of antibody. When the antibody level has reached a plateau, the animal can be exsanguinated or bled successively over a period of days

Review of Microbial Physiology and Genetics

The first portion of this section will deal with bacteria and fungi, their structure, chemical composition, and metabolism. This will be followed by a discussion of chemotherapeutic agents that are active against bacteria, fungi and animal parasites. The second section will deal with Basic Virology (viral structure, classification, replication and the effects of antiviral agents of viral replication). The last portion will deal with Microbial Genetics (mutations, gene transfer, and recombinant DNA technologies).

Comprehensive Review Examination

This exam was taken by a large group of sophomore medical students in 1991 (at the conclusion of a comprehensive review period) approximately two weeks before they took the National Board of Medical Examiners Comp I Test. The class mean on these questions was 69%. The mean score for these same students on the Comp I exam was 194 (at the 48th percentile).

Review of Microbial Genetics

The term mutation refers to an abrupt and usually stably inherited change in properties of an organism. Mutations can occur either spontaneously, or may be induced by a mutagen.

Review of Virology

The outermost component of a virion is the capsid, made up of protein subunits called capsomers. The capsid serves four important functions: (1) it protects the viral genome, (2) it aids in infection by attaching the virion to susceptible cells, (3) it is the stimulus for antibody production, (4) it serves as the antigen in serologic tests and (5) responsible for tissue tropism in naked viruses such as polio.

Review of Microbial Physiology

The cell wall of bacteria protects the cell against osmotic lysis. Both Gram positive and Gram negative bacteria have peptidoglycan (mucopeptide) as the innermost layer of the cell wall. They differ in amount, and in the nature of the surface layers.