Serological responses to mycoplasmas in HIV-infected and non-infected individuals.
OBJECTIVE
To assess the frequency of mycoplasma infections in HIV-antibody-positive and -negative individuals by studying the serological responses against mycoplasmas, especially Mycoplasma fermentans and M. pirum.


METHODS
An enzyme-linked immunosorbent assay (ELISA) was used to measure immunoglobulin G (IgG) class antibody concentrations against six mycoplasma species in sera of HIV-positive and HIV-negative individuals.


METHODS
Serum samples were obtained from 30 HIV-positive individuals (10 asymptomatics, 10 with lymphadenopathy syndrome and 10 with AIDS), 10 HIV-negative partners of HIV-positive individuals and 40 HIV-negative blood donors. Antibodies to M. fermentans strains incognitus and PG18, M. pirum, M. genitalium, M. pneumoniae and M. hominis were assessed by immunoblot or ELISA. Absorbance values were taken as a semiquantitative measurement for antibody concentration and an arbitrary cut-off value (0.8) was set to establish seroprevalence.


RESULTS
There was no significant difference in the mean IgG concentrations of any of the six mycoplasmas between HIV-positive and HIV-negative groups. Antibody concentrations were also similar in different clinical phases of HIV infection. Antibody concentrations to different mycoplasma strains were compared with each other to reveal eventual cross-reactions caused by shared antigens; the strongest correlation (r = 0.836) was found between M. fermentans strains incognitus and M. pirum antibody concentrations. The correlation between M. fermentans strains incognitus and PG18 was also significant but weaker (r = 0.522). No shared antigens between M. fermentans strain incognitus and M. pirum were demonstrated by immunoblot.


CONCLUSIONS
Antibodies against M. fermentans type strain PG18, strain incognitus and against M. pirum are detected infrequently and their presence does not correlate with HIV infection per se or with the clinical stage of HIV infection.
Hakkarainen
K
K
Institute of Biomedical Sciences, University of Tampere, Finland.
Jansson
E
E
Ranki
A
A
Valle
S L
SL
Krohn
K J
KJ
D000907:Antibodies, Bacterial / Q000097:blood*; D015331:Cohort Studies; D005260:Female; D005387:Finland / Q000453:epidemiology; D015658:HIV Infections / Q000453:epidemiology / Q000209:etiology / Q000382:microbiology*; D006679:HIV Seropositivity / Q000382:microbiology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D009174:Mycoplasma / Q000276:immunology* / Q000472:pathogenicity; D009175:Mycoplasma Infections / Q000150:complications / Q000453:epidemiology / Q000276:immunology; D016036:Seroepidemiologic Studies
D000907:Antibodies, Bacterial; D007074:Immunoglobulin G