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Background Chronic hepatitis B (CHB) is responsible for major disease burden worldwide. However, the number of available therapies is limited; cure remains an elusive goal. JNJ-64794964 (JNJ-4964) is an oral toll-like receptor-7 (TLR7) agonist being evaluated for the treatment of CHB. Here, we investigated the capacity of JNJ-4964 to induce transcriptomic and immune cell changes in peripheral blood in healthy volunteers.Methods Peripheral blood was collected in the JNJ-4964 first-in-human phase 1 trial at multiple time points to assess transcriptomics and changes in frequency and phenotype of peripheral-blood mononuclear cells. Correlation of changes to JNJ-4964 exposure (Cmax) and changes in cytokine levels (C-X-C motif chemokine ligand 10 [CXCL10] and interferon alpha [IFN-α]) were evaluated.Results Fifty-nine genes, mainly interferon-stimulated genes, were up-regulated between 6 hours and 5 days after JNJ-4964 administration. JNJ-4964 increased frequencies of CD69, CD134, CD137, and/or CD253-expressing natural killer (NK) cells, indicative of NK cell activation. These changes correlated with Cmax, increase of CXCL10, and induction of IFN-α and were observed at IFN-α levels that are associated with no/acceptable flu-like adverse events. JNJ-4964 administration resulted in increased frequencies of CD86-expressing B cells, indicative of B-cell activation. These changes were predominantly observed at high IFN-α levels, which are associated with flu-like adverse events.Conclusions JNJ-4964 administration led to changes in transcriptional profiles and immune cell activation phenotype, particularly for NK cells and B cells. Together, these changes could represent a set of biomarkers for the characterization of the immune response in CHB patients receiving TLR7 agonists.

Rituximab, which binds CD20 on B cells, is one of the best-characterized antibodies used in the treatment of B-cell malignancies and autoimmune diseases. Rituximab triggers natural killer (NK)-cell–mediated antibody-dependent cellular cytotoxicity (ADCC), but little is known about the spatial and temporal dynamics of cell-cell interactions during ADCC or what makes rituximab potent at triggering ADCC. Here, using laser scanning confocal microscopy, we found that rituximab caused CD20 to cap at the B-cell surface independent of antibody crosslinking or intercellular contact. Unexpectedly, other proteins, including intercellular adhesion molecule 1 and moesin, were selectively recruited to the cap of CD20 and the microtubule organizing center became polarized toward the cap. Importantly, the frequency at which NK cells would kill target cells via ADCC increased by 60% when target cells were polarized compared with when they were unpolarized. Polarized B cells were lysed more frequently still when initial contact with NK cells occurred at the place where CD20 was capped. This demonstrates that the site of contact between immune cells and target cells influences immune responses. Together, these data establish that rituximab causes a polarization of B cells and this augments its therapeutic function in triggering NK-cell–mediated ADCC.

Rituximab, which binds CD20 on B cells, is one of the best-characterized antibodies used in the treatment of B-cell malignancies and autoimmune diseases. Rituximab triggers natural killer (NK)-cell–mediated antibody-dependent cellular cytotoxicity (ADCC), but little is known about the spatial and temporal dynamics of cell-cell interactions during ADCC or what makes rituximab potent at triggering ADCC. Here, using laser scanning confocal microscopy, we found that rituximab caused CD20 to cap at the B-cell surface independent of antibody crosslinking or intercellular contact. Unexpectedly, other proteins, including intercellular adhesion molecule 1 and moesin, were selectively recruited to the cap of CD20 and the microtubule organizing center became polarized toward the cap. Importantly, the frequency at which NK cells would kill target cells via ADCC increased by 60% when target cells were polarized compared with when they were unpolarized. Polarized B cells were lysed more frequently still when initial contact with NK cells occurred at the place where CD20 was capped. This demonstrates that the site of contact between immune cells and target cells influences immune responses. Together, these data establish that rituximab causes a polarization of B cells and this augments its therapeutic function in triggering NK-cell–mediated ADCC.

The pathogenesis of acute rheumatic fever (ARF) is poorly understood. We identified two contiguous bacteriophage genes, designated speL and speM, encoding novel inferred superantigens in the genome sequence of an ARF strain of serotype M18 group A streptococcus (GAS). speL and speM were located at the same genomic site in 33 serotype M18 isolates, and no nucleotide sequence diversity was observed in the 33 strains analyzed. Furthermore, the genes were absent in 13 non-M18 strains tested. These data indicate a recent acquisition event by a distinct clone of serotype M18 GAS. speL and speM were transcribed in vitro and upregulated in the exponential phase of growth. Purified SpeL and SpeM were pyrogenic and mitogenic for rabbit splenocytes and human peripheral blood mononuclear cells in picogram amounts. SpeL preferentially expanded human T cells expressing T-cell receptors Vbeta1, Vbeta5.1, and Vbeta23, and SpeM had specificity for Vbeta1 and Vbeta23 subsets, indicating that both proteins had superantigen activity. SpeL was lethal in two animal models of streptococcal toxic shock, and SpeM was lethal in one model. Serologic studies indicated that ARF patients were exposed to serotype M18 GAS, SpeL, and SpeM. The data demonstrate that SpeL and SpeM are pyrogenic toxin superantigens and suggest that they may participate in the host-pathogen interactions in some ARF patients.

ABSTRACTThe pathogenesis of acute rheumatic fever (ARF) is poorly understood. We identified two contiguous bacteriophage genes, designated speLand speM, encoding novel inferred superantigens in the genome sequence of an ARF strain of serotype M18 group A streptococcus (GAS). speLand speMwere located at the same genomic site in 33 serotype M18 isolates, and no nucleotide sequence diversity was observed in the 33 strains analyzed. Furthermore, the genes were absent in 13 non-M18 strains tested. These data indicate a recent acquisition event by a distinct clone of serotype M18 GAS. speLand speMwere transcribed in vitro and upregulated in the exponential phase of growth. Purified SpeL and SpeM were pyrogenic and mitogenic for rabbit splenocytes and human peripheral blood mononuclear cells in picogram amounts. SpeL preferentially expanded human T cells expressing T-cell receptors Vβ1, Vβ5.1, and Vβ23, and SpeM had specificity for Vβ1 and Vβ23 subsets, indicating that both proteins had superantigen activity. SpeL was lethal in two animal models of streptococcal toxic shock, and SpeM was lethal in one model. Serologic studies indicated that ARF patients were exposed to serotype M18 GAS, SpeL, and SpeM. The data demonstrate that SpeL and SpeM are pyrogenic toxin superantigens and suggest that they may participate in the host-pathogen interactions in some ARF patients.

This article examines the work behaviors related to counseling substance‐abusing clients by mental health service providers in multiservice mental health agencies. The results support the need for specialized knowledge and skills in working with substance‐abusing clients.

Background:Staphylococcus aureuscolonizes the skin lesions of more than 90% of patients with atopic dermatitis (AD). The mechanism for increased S aureuscolonization in AD is unknown. However, the initial event in colonization requires adherence of S aureusto the skin. Objective:The purpose of this study was to examine the roles of various bacterial adhesins on S aureusbinding to AD skin. Methods:In an attempt to delineate the mechanism behind this adherence process, an in vitro bacterial binding assay was developed to quantitate the adherence of various S aureusstrains to AD, psoriatic, and normal skin sections. S aureusstrains used in this study were obtained either from cultures of AD skin lesions or from genetically manipulated strains of S aureusthat lacked specific microbial surface components recognizing adhesive matrix molecules (MSCRAMMs)—namely, fibronectin-binding protein (Fnbp), fibrinogen-binding protein (Clf), collagen-binding protein (Cna), and their parent strains. In addition, S aureusstrains from patients with AD were pretreated with fibronectin or fibrinogen to block MSCRAMM receptors and interfere with binding. Results:Under all experimental conditions, binding of S aureuswas localized primarily to the stratum corneum. Immunocytochemical staining of AD skin sections showed a redistribution of fibronectin to the cornified layer, an observation not seen in normal skin. S aureusbinding to uninvolved AD skin was significantly greater than the binding to uninvolved psoriatic skin (P< .0001) and normal skin (P< .0005). The Fnbp-negative S aureusshowed a significant reduction in binding to the AD skin (P< .0001) but not to the psoriatic and normal skin. In the AD skin, a significant reduction in the binding of S aureuswas also observed in the Clf-negative strain (P< .0001) but not in the Cna-negative S aureus. Preincubation of S aureuswith either fibronectin or fibrinogen also inhibited bacterial binding to AD skin (P< .0001). Conclusion:These data suggest that fibronectin and fibrinogen—but not collagen—play a major role in the enhanced binding of S aureusto the skin of patients with AD. (J Allergy Clin Immunol 2001;108:269-74.)

Neutrophils are markedly less sensitive to glucocorticoids than T cells, making it difficult to control inflammation in neutrophil-mediated diseases. Development of new antiinflammatory strategies for such diseases would be aided by an understanding of mechanisms underlying differential steroid responsiveness. Two protein isoforms of the human glucocorticoid receptor (GR) exist, GRα and GRβ, which arise from alternative splicing of the GR pre-mRNA primary transcripts. GRβ does not bind glucocorticoids and is an inhibitor of GRα activity. Relative amounts of these two GRs can therefore determine the level of glucocorticoid sensitivity. In this study, human neutrophils and peripheral blood mononuclear cells (PBMCs) were studied to determine the relative amounts of each GR isoform. The mean fluorescence intensity (MFI) using immunofluorescence analysis for GRα was 475 ± 62 and 985 ± 107 for PBMCs and neutrophils, respectively. For GRβ, the MFI was 350 ± 60 and 1,389 ± 143 for PBMCs and neutrophils, respectively (P < 0.05). After interleukin (IL)-8 stimulation of neutrophils, there was a statistically significant increase in intensity of GRβ staining to 2,497 ± 140 (P < 0.05). No change in GRα expression was observed. This inversion of the GRα/GRβ ratio in human neutrophils compared with PBMCs was confirmed by quantitative Western analysis. Increased GRβ mRNA expression in neutrophils at baseline, and after IL-8 exposure, was observed using RNA dot blot analysis. Increased levels of GRα/GRβ heterodimers were found in neutrophils as compared with PBMCs using coimmunoprecipitation/Western analysis. Transfection of mouse neutrophils, which do not contain GRβ, resulted in a significant reduction in the rate of cell death when treated with dexamethasone. We conclude that high constitutive expression of GRβ by human neutrophils may provide a mechanism by which these cells escape glucocorticoid-induced cell death. Moreover, upregulation of this GR by proinflammatory cytokines such as IL-8 further enhances their survival in the presence of glucocorticoids during inflammation.

Sexual attacks on older women committed by young adult males are a cause of much concern. Despite this there is very little on the subject in the psychiatric literature.This article reviews the available literature and describes a small series of cases, highlighting not only common themes, but also the diversity of psychopathology evident in the perpetrator.

This paper investigates the Theory of Mind ability of psychopaths. Happé's (1994) advanced test of Theory of Mind was presented to 25 psychopaths and 25 non-psychopathic incarcerated controls. The psychopaths and the non-psychopathic controls did not differ in their performance on this task. However, the psychopaths were performing significantly better than Happé's most highly able adult autistic population. It was therefore concluded that the psychopath does not have a Theory of Mind deficit. Speculations are made about the different developmental pathways of autism and psychopathy and the differences in the empathy deficit present in both these disorders.

BACKGROUND: Erythema multiforme and toxic epidermal necrolysis can occur as serious and even life-threatening adverse drug reactions. The underlying mechanisms are unknown, but evidence suggests that affected individuals may have impaired capacity to detoxify reactive intermediate drug metabolites. Such intermediates may be directly toxic or may react with host tissues to form antigens, evoking an immune response. We describe our investigation of a patient with carbamazepine-induced erythema multiforme and toxic epidermal necrolysis. The inflammatory infiltrate was examined immunocytochemically in lesional skin specimens from the patient, in the patient's patch test response to carbamazepine, and in lesional skin specimens from five other patients with drug-induced erythema multiforme. The patient's lymphocytes were examined both for susceptibility to cytotoxic damage by liver microsome—induced carbamazepine metabolites and for proliferative responses to native carbamazepine, which might indicate cell-mediated immune sensitization. OBSERVATIONS: Lesions of toxic epidermal necrolysis were more florid, but findings were essentially similar in all the skin samples examined. In the dermis there were CD14+ macrophages, CD1a+ Langerhans cells, and CD3+, CD45RO+ T cells. The CD4-CD8 T-cell ratio was 2:1, and 10% of the T cells were CD25+, suggesting activation by recent encounter with antigen. The epidermis contained CD14+ macrophages and T cells, but the CD8+ cells out-numbered the CD4+ cells. Up to 25% of the T cells were CD25+. Lymphocyte proliferation was not induced by native carbamazepine, but the patient's lymphocytes were significantly more susceptible to cytotoxic killing by liver microsome—induced carbamazepine intermediates. CONCLUSIONS: The inflammatory reaction in skin affected by erythema multiforme and toxic epidermal necrolysis was rich in CD8+ T cells, suggesting an immune cytotoxic reaction. The patient appeared to have a reduced capacity to detoxify reactive intermediates. This, together with the lack of lymphocyte response to native drug but a positive patch test response, suggests that the immune response may be directed at drug-modified epidermal cells.(Arch Dermatol. 1994;130:598-604)