Eyes Of Normal Mice Research Articles

Electron microscopy of the suckling mouse cataract agent: a noncultivable animal pathogen possibly related to mycoplasma.

The suckling mouse cataract agent (SMCA) is a filtrable (<220 nm), noncultivable agent isolated from ticks in Georgia in 1961. It grows to high titer in the eyes and brains of intracerebrally inoculated mice in which it induces cataract, uveitis, and chronic brain infection. SMCA in high titer may also be recovered from the tissues of embryonated hen eggs in which the infection is lethal within 4 to 9 days. Fine-structural studies of ultrathin sections of pellets obtained by ultracentrifugation of SMCA-infected egg allantoic fluids have revealed pleomorphic structures with morphological characteristics typical of mycoplasma. Similar organisms have been observed in egg allantoic fluids infected with an SMCA-related tick isolate, GT-48, but not in fluids from uninoculated control eggs. Mycoplasma-like entities were also observed in high concentration within retinal tissues of rats and mice studied at the time of maximal retinitis and uveitis after SMCA inoculation. Comparable tissues from normal mouse eyes were free of microorganisms. These fine-structural observations are in agreement with those reported by other investigators and suggest that SMCA-induced pathology is associated with an agent that resembles mycoplasma in size and morphology but differs from typical mycoplasma in its apparent non-cultivability on artificial media and its resistance to inactivation by broad-spectrum antibiotics.

Tumor inoculation into the eye of an alien species

In recent articles Keysser1 and his associate Hegner2 have reported the successful inoculation of carcinomata and sarcomata from man and from the mouse into the vitreous humor of rats, an outcome which they ascribe to the absence of protective substances in the eye and to the indifferent character of its proteins. The tumors were injected in the form of a fine emulsion, the bulb being entered on its posterior aspect in order to avoid hemorrhage with the consequent entry of protective bodies from the blood stream.Repetition of the experiment does not substantiate these claims. A few drops of a fine emulsion of Crocker Fund carcinoma No. 180 in Ringer's solution were injected under ether anesthesia into the eyes of rats, and a similar amount of the same emulsion into the eyes of normal mice to serve as controls; no hemorrhage occurred during the operation. The extreme proliferative capacity of this growth is shown by the fact that forty-nine mice out of fifty-four which survived for more than three weeks de...