A MOUSE CHEMOTAXIS ASSAY AS A SUBSTITUTE FOR THE MONKEY VITREOUS TEST

CURRENTLY, THE VITREOUS COMPARTMENT OF OWL MONKEYS IS USED TO EVALUATE VISCOELASTIC HYALURONAN OPHTHALMIC MEDICAL DEVICES BEFORE USE IN HUMANS. TO DATE, NO TEST OTHER THAN THE MONKEY VITREOUS TEST (MVT) HAS BEEN ABLE TO PREDICT, WITH THE REQUIRED CONSISTENCY, THE INFLAMMATORY/NONINFLAMMATORY NATURE OF HA MATERIALS. IT WOULD BE ADVANTAGEOUS TO HAVE A RELIABLE ALTERNATIVE THAT COULD PREDICT THE NATURE OF THE SUBSTANCE. IN ADDITION, OWLMONKEYS REPRESENT AN EXPENSIVE, LIMITED, AND EVER-DECREASING RESOURCE. THE MOUSE CHEMOTAXIS ASSAY WAS DEVELOPED AS A POTENTIAL SUBSTITUTE FOR THE MVT. PRELIMINARY TESTING WITH HA SAMPLESDEMONSTRATES THAT MVT RESULTS CORRELATE WITH MOUSE CHEMOTAXIS RESULTS AND THAT INFLAMMATORY AND NONINFLAMMATORY HA CAN BE DISTINGUISHED BY THE MOUSE CHEMOTAXIS ASSAY. IN THE MOUSE ASSAY, TEST MATERIAL IS INJECTED INTRAPERITONEALLY (IP); AFTER 24 HOURS, THE IP FLUID IS HARVESTED AND PLACED IN THE LOWER COMPARTMENT OF A CHEMOTAXIS CHAMBER. THE UPPER COMPARTMENT CONTAINS FRESH HUMAN LEUCOCYTES, AND THE COMPARTMENTS ARE SEPARATED BY A 2-MU M AND A 5-MU M MEMBRANE. AFTER 1.5 HOURS, THE MEMBRANES ARE HARVESTED AND EVALUATED (CELL NUMBER). INFLAMMATORY HAS HAS BEEN FOUND TO PRODUCE CHEMOTACTIC IP FLUID AND ELEVATED CELL COUNTS, WHILE NONINFLAMMATORY HA DOES NOT. FURTHER, THE POTENTIAL EXISTS FOR THE DEVELOPMENTOF A TOTALLY IN VITRO ASSAY NOT REQUIRING MICE.