Humoral response against Cryptococcus neoformans mannoprotein antigens in HIV-infected patients.
Twenty-four sera from healthy donors, 18 from HIV-positive patients (< 200 CD4+/mm3) and 18 sera collected before and during cryptococcosis from HIV-positive patients were analysed for the presence of humoral response to C. neoformans mannoproteins. Our results show that samples from healthy subjects and from HIV-positive patients had one of three antibody response profiles: (i) presence of reactive antibodies against both 105 and 80 kilodalton mannoproteins; (ii) presence of reactive antibodies against one of the two mannoproteins; or (iii) absence of reactive antibodies. Importantly the percentage of unreactive sera increased 6-fold in HIV-positive patients and more than 10-fold in patients with cryptococcosis. In addition, in the latter patients no variation of humoral response before and during cryptococcosis was observed. These results suggest that HIV-positive patients show a marked difficulty in mounting or maintaining antibody response to mannoprotein and this could contribute to predisposition to cryptococcosis.
Pitzurra
L
L
Microbiology Section, Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Italy.
Perito
S
S
Baldelli
F
F
Bistoni
F
F
Vecchiarelli
A
A
D000907:Antibodies, Bacterial / Q000032:analysis*; D000917:Antibody Formation; D000942:Antigens, Bacterial / Q000276:immunology*; D015153:Blotting, Western / Q000379:methods; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D003455:Cryptococcus neoformans / Q000276:immunology*; D015658:HIV Infections / Q000276:immunology* / Q000382:microbiology; D006801:Humans; D015151:Immunoblotting / Q000379:methods; D008562:Membrane Glycoproteins / Q000276:immunology*
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D008562:Membrane Glycoproteins; C025363:mannoproteins