Effect of chronic ethanol consumption on protective T-helper 1 and T-helper 2 immune responses against the parasites Leishmania major and Strongyloides stercoralis in mice.
BACKGROUND
Chronic alcohol consumption has been associated with significant increases in the prevalence of infectious diseases, and it has been suggested that these increases are caused by a direct effect of ethanol on the immune response. The objective of this study was to determine whether chronic ethanol consumption would affect the development of protective immunity to Leishmania major, which is controlled by the T-helper 1 (Th1) subset of CD4 cells, and Strongyloides stercoralis, which is controlled by the Th2 subset.


METHODS
Mice were fed ethanol-containing liquid diet (25% ethanol-derived calories), liquid isocaloric diet without ethanol, or solid chow and then exposed to either of the two parasites. The ability of the mice chronically consuming alcohol to eliminate the infections was determined, as were the levels of parasite-specific humoral and cellular immune responses.


RESULTS
Mice chronically consuming alcohol were capable of eliminating both of these infections in a manner identical to the control mice. In addition, splenocytes from mice chronically consuming alcohol infected with L. major produced nitric oxide at the same levels as in control mice. Antibody responses were altered in a manner suggesting an increase in Th2 immunity and a decrease in Th1 immunity in the mice chronically consuming alcohol. In mice chronically consuming alcohol that were infected with S. stercoralis, eosinophils migrated to the parasite's microenvironment, and antibodies were produced at levels equivalent to those seen in control mice.


CONCLUSIONS
Mice maintained on an ethanol-containing liquid diet had some alteration in their ability to produce Th1 and Th2 immune responses yet were capable of generating unimpaired protective Th1 and Th2 responses.
Krolewiecki
A J
AJ
Department of Microbiology and Immunology, Thomas Jefferson University Philadelphia, Pennsylvania 19107, USA.
Leon
S
S
Scott
P A
PA
Nolan
T J
TJ
Schad
G A
GA
Abraham
D
D
D000428:Alcohol Drinking / Q000276:immunology*; D000818:Animals; D002492:Central Nervous System Depressants / Q000494:pharmacology*; D000431:Ethanol / Q000494:pharmacology*; D005260:Female; D007074:Immunoglobulin G / Q000187:drug effects / Q000276:immunology; D018320:Leishmania major / Q000187:drug effects / Q000276:immunology*; D016773:Leishmaniasis, Cutaneous / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D017171:Strongyloides stercoralis / Q000187:drug effects / Q000276:immunology*; D013322:Strongyloidiasis / Q000276:immunology; D018417:Th1 Cells / Q000187:drug effects* / Q000276:immunology; D018418:Th2 Cells / Q000187:drug effects* / Q000276:immunology
D002492:Central Nervous System Depressants; D007074:Immunoglobulin G; D000431:Ethanol