Long-term serologic responses to the Pneumocystis jirovecii major surface glycoprotein in HIV-positive individuals with and without P. jirovecii infection.
BACKGROUND
The immune responses to Pneumocystis jirovecii major surface glycoprotein (Msg) in individuals with human immunodeficiency virus (HIV) infection are poorly understood.


METHODS
We examined the sequential serologic responses to recombinant Msg carboxyl terminus fragments (MsgC1, MsgC3, MsgC8, and MsgC9) by enzyme-linked immunosorbent assay in a cohort of individuals with HIV infection for the 5.5 years before death and autopsy. Analyses included mean antibody levels by status at death (Pneumocystis pneumonia, P. jirovecii colonization, or neither), factors associated with high antibody levels, and antibody responses before and after active Pneumocystis pneumonia.


RESULTS
Patients who died from Pneumocystis pneumonia had higher levels of antibody to MsgC8 than did patients who died from other causes. Previous episode of Pneumocystis pneumonia, geographic location, and age were independent predictors of high levels of anitbodies to most or all Msgs. Failure to take Pneumocystis pneumonia prophylaxis was associated with high levels of antibody to MsgC1. Patients who developed and recovered from active Pneumocystis pneumonia during the study exhibited an increase in serum antibody levels that persisted for months after the infection, whereas patients who developed another acquired immunodeficiency syndrome-defining illness did not.


CONCLUSIONS
Serum antibodies to Msgs are important markers of P. jirovecii infection in patients with HIV infection and are influenced by host and environmental factors in complex ways.
Walzer
Peter D
PD
Veterans Affairs Medical Center and Division of Infectious Diseases, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA. peter.walzer@va.gov
Djawe
Kpandja
K
Levin
Linda
L
Daly
Kieran R
KR
Koch
Judith
J
Kingsley
Lawrence
L
Witt
Mallory
M
Golub
Elizabeth T
ET
Bream
Jay H
JH
Taiwo
Babafemi
B
Morris
Alison
A
D000328:Adult; D000368:Aged; D000908:Antibodies, Fungal / Q000097:blood; D000935:Antifungal Agents / Q000627:therapeutic use; D001344:Autopsy; D005500:Follow-Up Studies; D005656:Fungal Proteins / Q000276:immunology*; D015658:HIV Infections / Q000150:complications* / Q000276:immunology / Q000401:mortality; D006801:Humans; D008562:Membrane Glycoproteins / Q000276:immunology*; D008875:Middle Aged; D010446:Peptide Fragments / Q000276:immunology; D045363:Pneumocystis carinii / Q000235:genetics* / Q000276:immunology*; D011020:Pneumonia, Pneumocystis / Q000150:complications* / Q000276:immunology / Q000401:mortality; D012703:Serotyping; D015996:Survival Rate; D013997:Time Factors
D000908:Antibodies, Fungal; D000935:Antifungal Agents; D005656:Fungal Proteins; D008562:Membrane Glycoproteins; D010446:Peptide Fragments