Immunohistochemical detection of alveolar macrophages and pulmonary giant cells and their diagnostic value in some types of asphyxia

ABSTRACT

The occurrence of numerous alveolar macrophages and pulmonary giant cells has been reported in both fatal asphyxia and other causes of death Pulmonary giant cells as a significant diagnostic tool in cases of asphyxia is still a controversial discussion. In the present study we investigated experimentally some types of asphyxia to detect both alveolar macrophages and pulmonary giant cells by immunohistochemical method using a monoclonal antibody Ki-Mlp, and to estimate the frequency,. of these cells microscopically in each group examined to evaluate the statistical differences which may help in differentiation between the various causes of death from asphyxia. Forty two adult albino rats were divided into 7 groups each contained 6 animals. The first group were sacrificed by decapitation and act as a control group. The animals of the 2nd and 3rd. groups were killed by obstructive asphyxia as strangulation and hanging respectively, while those of the 4th group were asphyxiated by drowning. The 5th 6 th and 7th groups included deaths of asphyxia due to inhalation of irritant gases as methanol either and butagaz respectively. Serial sections were prepared from formalin-fixed paraffin-embedded tissue specimens of lungs and brains, and were used for Hx and E and immunostaining. Alveolar macrophages and pulmonary giant cells in all groups of asphyxia stained positively with a monoclonal antibody Ki-Mlp. The frequency of these reactive cells showed a variation between the different types of asphyxia which may be useful in. the differentiation between the asphyxiated cases as this immunostaining method was easily and rapidly performed. No histiocytes could be observed in the brain tissues which served as a good negative control