Frequency and cytokine phenotype of blood T cells from premature infants responding to staphylococcal enterotoxin B.
The responder cell frequency (RCF) of premature (< 1900 g birth weight) infants' blood lymphocytes, which proliferate in cultures stimulated by staphylococcal enterotoxin B, falls from 1:3400 to about 1:8000 during the first 2 wk of life. Term infants, in contrast, show no fall in RCF. The reduced RCF in the premature infants affected cells that make interferon-gamma more than cells making IL-4. The reduced RCF was accompanied by a fall in the fraction of V beta 3+ T cells that entered cell cycle in stimulated cultures. The RCF of premature infants' T cells was increased in cultures supplemented with irradiated monocytes from adults. Addition of IL-4 (but not IL-2, IL-6, or indomethacin) increased the RCF and fraction of cells entering cell cycle of the premature infants. The data suggest that postnatal environmental factors limit the ability of premature infants' monocytes to support a T-cell response to staphylococcal enterotoxin B in vitro and that this limitation is overcome by adding IL-4.
Hayward
A R
AR
Department of Pediatrics, University of Colorado Health Sciences Center, Denver 80262, USA.
Cosyns
M
M
Zhang
Y
Y
D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D004768:Enterotoxins / Q000494:pharmacology*; D006801:Humans; D007201:Indicator Dilution Techniques; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood*; D007371:Interferon-gamma / Q000032:analysis*; D007376:Interleukin-2 / Q000032:analysis; D015847:Interleukin-4 / Q000032:analysis*; D015850:Interleukin-6 / Q000032:analysis; D010641:Phenotype; D013211:Staphylococcus aureus; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects*
D004768:Enterotoxins; D007376:Interleukin-2; D015850:Interleukin-6; D015847:Interleukin-4; C031818:enterotoxin B, staphylococcal; D007371:Interferon-gamma