ABSTRACT
Haemophiliacs exhibit a broad range of immune defects. In this regard we have investigated the functional capacity of purified polymorphonuclear (PMN) cell suspensions in a group of Human Immunodeficiency Virus (HIV)+ or HIV- patients. Our results provide evidence for a significant reduction of PMN-mediated chemotactic responsiveness, phagocytosis and killing in haemophiliacs regardless of HIV infection. The depressed response does not reflect a PMN intrinsic dysfunction, since respiratory burst activity and lysosomal enzyme release from haemophilic PMN are unaffected in comparison to healthy donors. Quite interestingly the pretreatment of PMN from normal donors with either HIV+ or HIV- haemophilic sera gives rise to a reduction of PMN activity. Moreover, the suppressive effect is abrogated by serum heat inactivation. Taken together, these findings indicate a role for serum suppressive factors in the imbalance of PMN functional capacity in haemophilia regardless of HIV infection.
Subject(s)
Hemophilia A/immunology , Hemophilia B/immunology , Immune Tolerance/immunology , Neutrophils/immunology , Adolescent , Adult , Chemotaxis, Leukocyte/immunology , Child , Cytotoxicity, Immunologic/immunology , HIV Seropositivity/immunology , Humans , Neutrophils/enzymology , Phagocytosis/immunologyABSTRACT
Since previous data have provided conflicting results on immunoresponsiveness in senile dementia, Alzheimer type (SDAT), we evaluated the immune function in groups of SDAT patients and aged and young donors. In comparison to the younger subjects, SDAT and aged subjects did not exhibit significant differences in lymphocyte surface markers. Both groups of aged donors showed decreased B cell polyclonal responsiveness in a nonspecific T cell-driven B lymphocyte differentiation system. The use of an antigen-specific induction assay revealed an imbalance of T helper (Th) or T suppressor function in the elderly, while SDAT individuals were characterized by decreased Th activity. At the same time, aged individuals manifested an impairment of leukocyte-inhibiting factor (LIF) and lymphocyte-derived chemotactic factor production; a selective deficit of LIF release was seen in SDAT. Finally, elderly individuals displayed a decline of polymorphonuclear cell (PMN)-mediated functions and monocyte phagocytosis; only a decrease in PMN response was observed in SDAT. These results reveal discrepancies in impaired immune responses between SDAT and aging.
