Systemic aspergillosis in a patient with non-Hodgkin's lymphoma developing acute graft-versus-host disease after autologous peripheral blood stem cell transplantation.

Graft-versus-host disease (GVHD) is rare in the autologous setting. We describe a non-Hodgkin's lymphoma case developing acute GVHD after autologous peripheral blood stem cell transplantation following several lines of chemotherapy inclusive of fludarabine. At day +33, he complained of fever, diffused erythematous papulosis with ulceration of skin lesions. A punch biopsy indicated a grade III GVHD. A dose escalation of corticosteroids, cyclosporin-A and photoapheresis induced a transient response. He developed positivity to CMV and systemic aspergillosis. He died at day +185 in haematological complete remission, despite infection-oriented treatment. In spite of the use of prophylactic immunosuppressive drugs, between 50% and 70% of patients given HLA-identical marrow graft develop acute graft-versus-host disease (GVHD) that, in turn, significantly increases the risk of transplant-related mortality. Autologous BMT has been shown to be an effective procedure in several malignancies, persistently becoming a first-line choice in treating patients affected with lymphoproliferative disorders, specially non-Hodgkin's lymphoma (NHL). Although GVHD is a very rare event in the autologous setting (AuGVHD), a consistent number of reports dealing with GVHD-like phenomena has emerged, especially in breast cancer patients. More often, AuGVHD has been induced by the use of immunosuppressive agents, such as cyclosporin-A (CSA), in attempt to evoke a graft-versus-tumor (GVT) effect. However, AuGVHD is mild and self-limited phenomenon. We report the case of a NHL patient who developed unresponsive GVHD after autologous peripheral blood stem cell transplantation (PBSCT). Because of the immunosuppressive therapies, he developed systemic aspergillosis. He died in haematological complete remission despite infection-oriented treatment.

Beta 2 integrins are involved in cytokine responses to whole Gram-positive bacteria.

Proinflammatory cytokines have an important pathophysiologic role in septic shock. CD14 is involved in cytokine responses to a number of purified bacterial products, including LPS. However, little is known of monocyte receptors involved in cytokine responses to whole bacteria. To identify these receptors, human monocytes were pretreated with different mAbs and TNF-alpha was measured in culture supernatants after stimulation with whole heat-killed bacteria. Human serum and anti-CD14 Abs significantly increased and decreased, respectively, TNF-alpha responses to the Gram-negative Escherichia coli. However, neither treatment influenced responses to any of the Gram-positive bacteria tested, including group A and B streptococci, Listeria monocytogenes, and Staphylococcus aureus. Complement receptor type III (CR3 or CD18/CD11b) Abs prevented TNF-alpha release induced by heat-killed group A or B streptococci. In contrast, the same Abs had no effects when monocytes were stimulated with L. monocytogenes or S. aureus. Using either of the latter bacteria, significant inhibition of TNF-alpha release was produced by Abs to CD11c, one of the subunits of CR4. To confirm these blocking Ab data, IL-6 release was measured in CR3-, CR4-, or CD14-transfected Chinese hamster ovary cells after bacterial stimulation. Accordingly, streptococci triggered moderate IL-6 production (p < 0.05) in CR3 but not CD14 or CR4 transfectants. In contrast, L. monocytogenes and S. aureus induced IL-6 release in CR4 but not CR3 or CD14 transfectants. Collectively our data indicate that beta 2 integrins, such as CR3 and CR4, may be involved in cytokine responses to Gram-positive bacteria. Moreover, CD14 may play a more important role in responses to whole Gram-negative bacteria relative to Gram-positive ones.

Human monocyte receptors involved in tumor necrosis factor responses to group B streptococcal products.

Several group B streptococcal products have been previously found to stimulate human monocytes to produce tumor necrosis factor alpha. In order to identify the receptors involved in these responses, monocytes were stimulated with purified group- or type-specific carbohydrates or lipoteichoic acid in the presence of anti-receptor monoclonal antibodies, soluble CD14, or lipopolysaccharide-binding protein. Results indicate that CD14 plays an important role in tumor necrosis factor alpha responses to all of the stimuli tested. Moreover, both CD14 and complement receptor type 3 may be involved in responses to the group-antigen.

Role of IL-10 in a neonatal mouse listeriosis model.

This study was undertaken to test the hypothesis that altered IL-10 production plays a role in the increased susceptibility of neonates to listeriosis. Plasma IL-10 levels were measured in neonatal and adult mice at various times after infection with Listeria monocytogenes. Relative to adults, neonatal mice had markedly increased IL-10 levels early in the course of infection with Listeria using a 90% lethal dose. Higher neonatal IL-10 responses were also observed after injecting adults and pups with equal doses of killed organisms. Splenic macrophages from neonates produced higher IL-10 levels than those of adults after in vitro stimulation with killed bacteria, confirming in vivo observations. Moreover, IL-10 blockade had differential effects in neonates and adults infected with live Listeria. In adult mice, anti-IL-10 Abs decreased bacterial burden early in the course of infection, but were no longer effective at 6 days or later after challenge. In the pups, however, the same treatment had beneficial effects both early and late during infection and resulted in increased survival. Collectively, our data suggest that an overproduction of IL-10 by macrophages may at least partially explain the increased susceptibility of neonates to listeriosis, and provide further evidence that cytokine production is different in adults and neonates.

Neonatal hypersusceptibility to endotoxin correlates with increased tumor necrosis factor production in mice.

Septic shock is a major cause of mortality in neonates. The hypothesis was tested that neonatal age is associated with altered sensitivity to shock-inducing bacterial products or proinflammatory cytokines (or both). Mice of different ages were inoculated with various doses of lipopolysaccharide (LPS), superantigenic staphylococcal enterotoxin B (SEB), or recombinant tumor necrosis factor-alpha (rTNF-alpha), alone or in combination with the sensitizing agent D-galactosamine. Neonatal mice were markedly more susceptible to LPS-induced lethality but more resistant to SEB than were adults (P < .05). Mice of different ages did not differ, however, in their sensitivity to lethal activities of rTNF-alpha. Neonatal susceptibility to LPS and SEB correlated directly with plasma TNF-alpha but not IFN-gamma levels, which was confirmed by TNF-alpha and IFN-gamma blockade experiments. These data document marked age-related differences in the pathophysiology of septic shock and suggest that IFN-gamma is not an obligatory mediator of either LPS- or SEB-induced lethality in neonates.

Improved survival and antagonistic effect of sodium fusidate on tumor necrosis factor alpha in a neonatal mouse model of endotoxin shock.

Unlike the antibiotics erythromycin and penicillin G, sodium fusidate (fusidin) pretreatment (80 mg/kg of body weight) increased the survival rate of neonatal BALB/c mice challenged with Salmonella enteritidis lipopolysaccharide. Fusidin also significantly reduced the plasma tumor necrosis factor alpha levels. Hence, fusidin may prove useful in the management of bacterial sepsis in humans.