Wagner R P, Levitz S M, Tabuni A, Kornfeld H
Evans Department of Clinical Research, Boston University School of Medicine, MA 02118.
Am Rev Respir Dis. 1992 Dec;146(6):1434-8. doi: 10.1164/ajrccm/146.6.1434.
Cryptococcus neoformans infections are a major cause of morbidity and mortality for HIV-infected persons. Containment of the initial respiratory inoculation to the lung appears defective in patients with AIDS despite the low burden of HIV in bronchoalveolar macrophages. We have studied the fungistatic activity of human bronchoalveolar macrophages (BAM) cultured with an encapsulated strain of C. neoformans in the presence of pooled human serum. We observed 51.6% fungistasis after 24 h of culture. Fungistasis was diminished if the pooled human serum was heat-inactivated but was not affected by anticryptococcal capsular IgG. HIV envelope protein (gp120) has been shown to interfere with lymphocyte activation in vitro. We studied the effects of gp120 on BAM function and found that fungistatic activity was inhibited 25% (p < 0.001). Although binding of yeasts was not affected, gp120 inhibited the internalization of bound yeasts by 46% (p = 0.025). These experiments indicate that gp120 decreases the internalization and fungistasis of C. neoformans by human BAM, and they suggest a mechanism to explain how a small number of HIV-1-infected cells in the lung could impair the containment of C. neoformans.
新型隐球菌感染是艾滋病毒感染者发病和死亡的主要原因。尽管支气管肺泡巨噬细胞中的艾滋病毒载量较低，但艾滋病患者对肺部初始呼吸道接种的控制似乎存在缺陷。我们研究了在人混合血清存在的情况下，用新型隐球菌包膜菌株培养的人支气管肺泡巨噬细胞（BAM）的抑菌活性。培养24小时后，我们观察到51.6%的抑菌作用。如果人混合血清经热灭活，抑菌作用会减弱，但不受抗新型隐球菌荚膜IgG的影响。艾滋病毒包膜蛋白（gp120）已被证明在体外会干扰淋巴细胞激活。我们研究了gp120对BAM功能的影响，发现抑菌活性被抑制了25%（p < 0.001）。虽然酵母的结合不受影响，但gp120使结合酵母的内化减少了46%（p = 0.025）。这些实验表明，gp120会降低人BAM对新型隐球菌的内化和抑菌作用，并提示了一种机制来解释肺部少量感染艾滋病毒-1的细胞如何损害对新型隐球菌的控制。
