This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Nian Chen Articles by Pond, S. M. Search for Related Content PubMed PubMed Citation Articles by Nian Chen, Articles by Pond, S. M. Social Bookmarking                         What's this?

Prevention of Paraquat Toxicity in Suspensions of Alveolar Type II Cells by Paraquat-Specific Antibodies

University of Queensland Department of Medicine, Princess Alexandra Hospital, Brisbane, Q, 4102, Australia

Mark R. Bowles

University of Queensland Department of Medicine, Princess Alexandra Hospital, Brisbane, Q, 4102, Australia

Susan M. Pond

University of Queensland Department of Medicine, Princess Alexandra Hospital, Brisbane, Q, 4102, Australia

1 The herbicide, paraquat, is accumulated by the energy-dependent polyamine uptake pathway of alveolar type II cells. There it undergoes redox cycling that results in an amplified production of toxic reactive oxygen species and depletion of NADPH and other reducing equivalents. These processes account for the lung being the major target organ for paraquat toxicity.

2 We postulated that paraquat-specific antibodies would inhibit the uptake of the herbicide by type II cells and prevent its toxicity. Accordingly, we examined the effects of paraquat-specific monoclonal antibodies and Fab fragments on the uptake, efflux and cytotoxicity of 50 µM paraquat in suspensions of alveolar type II cells isolated from the rat.

3 The uptake of paraquat was linear over 40 min. Over this time, the uptake rate was inhibited significantly (% inhibition, 73-89) by IgG (25 or 50 µM) or Fab fragments (50 or 100 µM).

4 The apparent efflux rate of paraquat, studied over 16 h, was increased significantly from 0.12 h^-1 for the control cells in medium to 0.17 h^-1 by paraquat-specific Fab fragments but was unaffected by the specific IgG.

5 Cytotoxicity was determined by measuring the release of ⁵¹Cr from the cells. The cytotoxicity of 50 µM paraquat was decreased significantly (percent decrease, 56-80%) in the presence of specific antibodies.

6 These studies in vitro suggest some potential for immunotherapy in selected cases of paraquat poisoning.

Human & Experimental Toxicology, Vol. 13, No. 8, 551-557 (1994)
DOI: 10.1177/096032719401300808


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?