21. Secondly, perforin permits delivery of the cytotoxic granzymes A and B into target cells . 22. Natural hormones connect with receptors and switch on or off functions within target cells . 23. Cytotoxic drugs administered during chemotherapy target cells with fast turnovers such as malignant cells. 24. In addition to killing their target cells , granzymes can target and kill intracellular pathogens. 25. This mode of transport increases virulence by aiding in EHEC-Hly delivery to target cells . 26. There also seems to be a link between IFN-? production and killing of target cells . 27. When HIV infects its target cell it requires fusion of the viral and cellular membranes. 28. Synaptic signaling, an integral part of nervous system activity, occurs between neurons and target cells . 29. These channels disrupt the cell membrane of target cells , leading to cell lysis and death. 30. So neurons that are quiet when others throb lose their grip on the target cell .
