CD4 Antigens/metabolism; HIV Envelope Protein gp120/pharmacology; HIV Envelope Protein gp160/pharmacology; Isoenzymes/antagonists & inhibitors; Lymphocyte Activation/drug effects; Proteins/antagonists & inhibitors; Signal Transduction/drug effects; T-Lymphocytes/drug effects; T-Lymphocytes/immunology; Type C Phospholipases/antagonists & inhibitors; Antibodies, Monoclonal/immunology; Antibodies, Monoclonal/pharmacology; CD4 Antigens/immunology; CD4 Antigens/pharmacology; Calcium/metabolism; Calcium-Calmodulin-Dependent Protein Kinases/antagonists & inhibitors; GTPase-Activating Proteins; HIV Envelope Protein gp120/metabolism; HIV Envelope Protein gp160/metabolism; Humans; Isoenzymes/metabolism; Ligands; Mitogen-Activated Protein Kinase 1; Phospholipase C gamma; Phosphorylation/drug effects; Protein Binding/drug effects; Protein Binding/immunology; Protein Serine-Threonine Kinases/antagonists & inhibitors; Proteins/metabolism; Proto-Oncogene Proteins/antagonists & inhibitors; Proto-Oncogene Proteins c-raf; Proto-Oncogene Proteins p21(ras)/antagonists & inhibitors; Proto-Oncogene Proteins p21(ras)/drug effects; Type C Phospholipases/metabolism; ras GTPase-Activating Proteins