Synthetic peptide-based immunoassays for distinguishing between human T-cell lymphotropic virus type I and type II infections in seropositive individuals

Abstract

Until now, serologic tests that distinguish the closely related human T-cell lymphotropic virus types I (HTLV-I) and II (HTLV-II) infections have not been available. Synthetic peptide assays, employing peptides derived from the core and envelope proteins of HTLV-I and HTLV-II (SynthEIA and Select-HTLV tests), were evaluated for the ability to serologically discriminate HTLV-I and HTLV-II infections. Of 32 HTLV-Iand 57 HTLV-II-positive serum specimens from individuals whose infections were confirmed by polymerase chain reaction, the SynthEIA test categorized 29 (91%) as HTLV-I and 50 (88%) as HTLV-II, and 10 (11%) were nontypeable. In contrast, the Select-HTLV test categorized 32 (100%) as HTLV-I and 55 (96%) as HTLV-II, and 2 (2%) were nontypeable. The specificity of both the assays in seropositive serum specimens was 100% in that none of the specimens were incorrectly classified. Additional serum specimens obtained from clinically diseased patients from the United States (n = 8) and asymptomatic carriers and patients from Japan (an endemic population for HTLV-I; n = 40) were categorized as HTLV-I by at least one of the assays, while serum specimens from Guaymi Indians from Panama (an endemic population for HTLV-II; n = 13) were categorized as HTLV-II. Thus, peptide enzyme immunoassays appear to represent a simple technique employing chemically synthesized antigens for discrimination between antibodies of HTLV-I and HTLV-II.

Sensitivity and specificity of human T‐lymphotropic virus (HTLV) types I and II polymerase chain reaction and several serologic assays in screening a population with a high prevalence of HTLV‐II

“…However, the sensitivity of recent HTLV‐I EIAs for HTLV‐II antibody is controversial, particularly as evidence accumulates that HTLV‐II is not benign 12,14 . WB assays, particularly those incorporating a recombinant envelope protein (rgp21e) 16 or/and the HTLV‐I‐ and HTLV‐II‐specific recombinant proteins MTA‐1 and K55, respectively, 17 or HTLV‐I and ‐II type‐specific synthetic peptides, 18 are both sensitive and specific but impractical for screening larger numbers of samples. In the United States, the WB has been used for supplemental or confirmatory testing of samples with positive screening results on EIAs, 15 but the lack of Food and Drug Administration licensure of HTLV WBs has recently limited their use.…”

Serologic confirmation of simian T-lymphotropic virus type I infection by using immunoassays developed for human T-lymphotropic virus antibody detection

“…Significant homologies of the transmembrane proteins of all known retroviruses may account for the false-positive rates. On the other hand, the r2lenv reactivity recently been utilized for serologic differentiation of HTLV-I abeys, and 3 of 4 from HTLV-II (16,17). Our analysis of these STLV- (22).…”

“…Synthetic-peptide-based immunoassay. A synthetic-peptide-based immunoassay (Select-HTLV; Coulter Immunology) which discriminates between HTLV-I and HTLV-II infection was performed as previously described (16). Briefly, wells coated with synthetic peptide (HTLV-I-specific p199a9 and HTLV-II-specific gp52enV) were incubated with 100 ,u1 of test serum at a 1:50 dilution and incubated at room temperature for 30 min.…”

“…developed which are highly sensitive and specific for the detection of env antibodies in HTLV-infected serum specimens (18,19). In addition, synthetic peptide and recombinant protein-based assays have provided a simple tool to increase the specificity of env detection and serologically distinguish between HTLV-I and HTLV-II (16,19). Because of significant conservation of primary amino acids between HTLV-I and STLV-I (15, 25), we sought to determine the usefulness of these recombinant constructs to detect env antibodies in STLV-I-infected monkey serum specimens.…”

Evaluation of real time PCR technique to diagnosis of human T-lymphotropic virus type I (HTLV-I) in patients in the Hematologia da Fundação Hemope Hospital, in Northeastern Brazil

“…The discriminatory serological tests are themselves based on research into antibodies produced to combat specific epitopes of each HTLV type. For this reason, immunonenzymatic assays, which contain synthetic peptides which are type-specific antigens, 4 or Western blot modified assays, which incorporate recombinant antigens which are type-specific to viral lysate, 5 are used. However, it should be remarked that, in some cases, even the discriminatory serological tests are not always capable of identifying the type of HTLV responsible for the infection, which makes it more difficult to provide individuals with the appropriate medical advice.…”