Immunological Characterization Of The Human Immunodeficiency Virus Type 1 Reverse Transcriptase Protein By The Use Of Monoclonal Antibodies

Abstract

Eighteen monoclonal antibodies (MAbs) directed against the purified human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) protein were produced. The antibodies were characterized by competitive ELISAs and Western blot experiments, and with nested, nine amino acid long peptides representing the whole 560 amino acid RT protein. By ELISA, the MAbs react with a minimum of seven epitopes of the protein. Four of the epitopes were located on the Nterminal 51K subunit and the remaining three epitopes were located at the C-terminal end of the protein.Using synthetic peptides, two epitopes at the Nterminal part were located at amino acids 294 to 302 and 350 to 354, respectively, from the N-terminal start of the protein. One epitope was located at amino acids 442 to 450, just after the cleavage site between the Nterminal and C-terminal subunit at position 440. Antibodies located at amino acids 294 to 302 could inhibit the RT enzymic activity of the protein. Two other MAbs, directed at the N-terminal and C-terminal parts of the protein, could also inhibit RT activity.

A novel neutralization epitope on the 'thumb' subdomain of human immunodeficiency virus type 1 reverse transcriptase revealed by a monoclonal antibody

“…Although most of these MAbs have been ineffective in neutralizing the polymerase activities of RT (Hansen et al, 1988;Tisdale et al, 1988;Ferris et aI., 1990;Li et at., 1993), a few inhibitory MAbs have been reported (Ferns et al, 1991;Orvell et al, 1991;Szilvay et al, 1992;Restle et al, 1992;Wu et al, 1993), and these may point to functionally important sites of RT. For example, MAb 28 (Restle et at., 1992) and MAb 1E8 (Wu et al, 1993) are involved in blocking binding of deoxynucleoside triphosphate substrate to the enzyme.…”

Human immunodeficiency virus‐1 reverse transcriptase immunodominant CD4+ T cell epitopes: A peptide‐based multiparametric assessment in the mouse

“…It will be of interest to explore the ability of the peptide fragments identified in this study to preferentially trigger Thl or Th2 cell subsets. It is of great interest that several of the immunodominant Th sites appear to be close to B cell sites previously described either in BALB/c mice [9] and/or in HIV-1-infected patients [6] [e.g. pep26 (RT276-290), pep41 (RT.411-425) or pep54 (RT528-544)], or class I-restricted regions defined in seropositive patients [12] [e.g.…”

DNA-Encoding Enzymatically Active HIV-1 Reverse Transcriptase, but Not the Inactive Mutant, Confers Resistance to Experimental HIV-1 Challenge

“…A number of monoclonals have been described, a few of them inhibiting the reverse transcription. Most antibodies appear to bind to conformational sites and could not be easily mapped to the linear regions of the RT [3,4]. Loss of protection in our case may have been linked to the cellular response to several linear and conformational epitopes.…”

“…Antibodies to certain epitopes of RT inhibits its enzymatic activity [3,4]. A high prevalence of these antibodies was associated with asymptomatic infection and an inability to isolate the virus from HIV-1-positive individuals [5,6].…”