The use of a passive hemolysis system to evaluate the complement activities of six mammalian species.

The study presents a new assay system for comparing the hemolytic activity of complements from different mammalian species. The passive hemolysis system uses the same antigen and antibodies from one species to minimize variations.

Research Methodology

• The researchers utilized a passive hemolysis assay system, which allowed the comparison of the hemolytic activities of complement (C) derived from six different mammalian species.
• This system uses only one kind of antigen – a substance that elicits an immune response – and antibodies generated from a single species.
• The intention was to reduce fluctuations that may occur due to variations in the target antigens being used and differences of using antibodies created in various species.

Research Findings

• The erythrocytes (E), or red blood cells, from horses and guinea pigs were found to be the most susceptible to lysis, the process where cells break down.
• One or both these species could potentially be utilized for measuring complement activity in species that have not been studied before.
• The horse serum was determined to have the least amount of complement activity among all the species tested. It only achieved lysis at high concentrations and the hemolytic activity drastically reduced even with small dilutions.

Implications of the Study

• The data in the study can also be potentially applied for the selection of target erythrocytes for future complement studies. These studies would use direct lysis, where antibodies raised against the cells destroy them.
• Offering an improved, standardized hemolytic activity methodology, it presents ways to better compare and understand the immune responses and complement activities among different species.