Growth hormone inhibits normal B-cell differentiation and neutrophils' chemotaxis in vitro.
In acromegalic patients we have previously described a low ability of B-lymphocytes to differentiate into plasma cells under PWM stimulation, and a decreased chemotaxis of polymorphonuclear leukocytes (PMN) towards N-formylmethionylphenilalanine (FMP). In this study we examined the effect of exogenous GH over these immune functions in normal cells. PMN were purified by dextran sedimentation, incubated with recombinant human GH (0 to 20 ng/ml) and subjected to stimulation with FMP. PBMC were cultured with or without PWM, in the presence of GH (between 0 and 100 ng/ml). Plasma cells were determined as hemolysis plaque forming cells and also by immunofluorescence. GH, in a dose-dependent way, decreased directed migration of PMN (5 ng/ml: 1.787 +/- 148 microns; 10 ng/ml: 1.581 +/- 221 microns; 20 ng/ml: 1.569 +/- 149 microns, all as mean +/- S.E.M.), when compared to similar values of untreated PMN (0 ng/ml 2.085 +/- 139 microns). GH treatment did not modify spontaneous migration. Net migration showed the same pattern as directed migration. GH decreased dose-dependently the PWM-driven differentiation of B-lymphocytes into plasma cells to 60% of the basal level. Although not significantly, GH tended to increase spontaneous B-cell differentiation. These results could account for the already described defect in B-cell differentiation and PWN chemotaxis in acromegaly, emphasizing the relationship between the endocrine and immune systems.
Fornari
M C
MC
IO/IIHEMA Academia Nacional de Medicina, Buenos Aires, Argentina.
Scolnik
M P
MP
Palacios
M F
MF
Intebi
A D
AD
Diez
R A
RA
D000328:Adult; D001402:B-Lymphocytes / Q000187:drug effects*; D002454:Cell Differentiation / Q000187:drug effects; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D003864:Depression, Chemical; D005260:Female; D013006:Growth Hormone / Q000494:pharmacology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects*; D011043:Pokeweed Mitogens / Q000494:pharmacology
D011043:Pokeweed Mitogens; D009240:N-Formylmethionine Leucyl-Phenylalanine; D013006:Growth Hormone