Colony inhibition test

Figure 12.1 Harvester ant foragers are stimulated to leave the nest in search of seeds in response to cues present in the task-specific cuticular hydrocarbon profile of patrollers. After inhibition of foragers at harvester ant colonies by removal of patrollers, colony foraging behavior was rescued by the addition of ant mimics, glass beads coated with task-specific cuticular hydrocarbons from patrollers, to the nest entrance at a rate of 1 bead every 10 seconds. Data were normalized to account for differences in the absolute number of foragers active each day. The same letters above bars denote statistical significance using a Tukey s post-hoc test. From Greene and Gordon, 2003.

Measure cell death, inhibition of cell growth, cell proliferation or colony formation. The number of cells, amount of protein, release of enzyme, release of vital dye, reduction of vital dye or other measurable parameters may he quantified by objective means. The objective measure and response is recorded in the test report. 

Leukocyte agglutination tests have often been used, but the results have been difficult to interpret and widely questioned (Flandrin et al. 1971 Gross and Hellriegel 1976). Recently, two new techniques have been described. One involves inhibition of granulocyte colonies in the presence of the patient s serum (Barrett et al. 1976). Using this technique, the authors were able to show amidopyrine-dependent leukagglutinin 6 and 12 months after the acute episode of agranulocytosis. In another study (Jeannet et al. 1979) a Cr release cytotoxicity test was used and auto-antibodies (probably induced by amidopyrine) specific for neutrophils and leukocytes were detected. 

A drag resistance test is used to determine the drag susceptibility of mycobacteria to different types of antibiotics. In this test, the collected specimen from the patient is cultivated on suitable media. Then paper disks of diameter 5 mm containing different kinds of antibiotics are placed on the media surface. After the incubation period (6—8 weeks), an inhibition zone appears around the colonies. By observing the diameters of the formed inhibition zones around each disk, we can know which antibiotic is the most effective to the bacterial population. 

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