Agglutination Reactions

Agglutination is defined as the antigen-antibody reaction in which antibodies cross-link particulate antigens resulting in the visible clumping of particles. Antibodies that show such reactions are called agglutinins. Agglutination reactions work on the principle of cross-linking of the polyvalent antigens. Following are the advantages of agglutination reactions:  easy to perform  require no expensive equipment, and  detectsContinue reading “Agglutination Reactions”


Synonym: Localized Anaphylaxis  Introduction: Atopy is defined as the tendency of an individual to produce IgE antibodies in response to various environmental antigens and thus develop strong immediate hypersensitivity (allergic) responses. Individuals with allergies to environmental antigens (e.g., pollen, house dust) are atopic.  Localized anaphylaxis involves reactions limited to a specific target tissue or organ andContinue reading “Atopy”

Antigen presenting cells

Introduction The population of specialized cells:  to capture microbial and other antigens, display MHC complexes in association with these peptide fragments of protein antigens on its surface to lymphocytes, and provide signals that stimulate the proliferation and differentiation of the lymphocytes (co-stimulatory signal) are known as the antigen-presenting cells (APCs).  APCs are conventionally referred toContinue reading “Antigen presenting cells”


Synonym: Programmed cell death Pronunciation: ah-poh-toh’-sis: Greek, (1) apo- away from and (2) ptosis, a falling or dropping  ‘Apoptosis’ has been derived from a Greek word that describes the falling of the leaves from a tree or petals from a flower. This term was coined to differentiate this form of programmed cell death from theContinue reading “Apoptosis”


Introduction: Aminoglycosides comprise a complex group of drugs derived from soil Actinomycetes in the genera Streptomyces and Micromonospora that impairs ribosome function and has antibiotic potential.  Examples includes Streptomycin, gentamicin, tobramycin, and, amikacin. Mode of Action: This complex group of drugs inserts itself on sites on the 30S ribosomal subunit of the prokaryotes and causesContinue reading “Aminoglycosides”