Peripheral natural killer cells in chronic hepatitis B patients display multiple molecular features of T cell exhaustion.

Antiviral effectors such as natural killer (NK) cells have impaired functions in chronic hepatitis B (CHB) patients. The molecular mechanism responsible for this dysfunction remains poorly characterised. We show that decreased cytokine production capacity of peripheral NK cells from CHB patients was associated with reduced expression of NKp30 and CD16, and defective mTOR pathway activity. Transcriptome analysis of patients NK cells revealed an enrichment for transcripts expressed in exhausted T cells suggesting that NK cell dysfunction and T cell exhaustion employ common mechanisms. In particular, the transcription factor TOX and several of its targets were over-expressed in NK cells of CHB patients. This signature was predicted to be dependent on the calcium-associated transcription factor NFAT. Stimulation of the calcium-dependent pathway recapitulated features of NK cells from CHB patients. Thus, deregulated calcium signalling could be a central event in both T cell exhaustion and NK cell dysfunction occurring during chronic infections.

Concurrent temporal (giant cell) arteritis and malignancy: report of 20 patients with review of the literature.

OBJECTIVE: To determine the frequency of occurrence of malignancy concurrently with temporal arteritis (TA), as well as features and outcome of the vasculitis in such cases. METHODS: In a series of 271 consecutive patients with TA (219 biopsy-proven), we retrospectively analyzed the frequency and type of malignancy concurrent with vasculitis (less than 1 year before or after), as well as the main features and outcome of TA in this setting. We also surveyed all cases published in the French-British literature. RESULTS: We observed 20 patients with TA and concurrent malignancy and reviewed 27 similar published reports. GCA was documented pathologically in 86% of the cases. The time between diagnosis of TA and that of malignancy averaged 3.5 months (synchronous diagnoses in 27 patients). Various locations of cancers were found, particularly the gastrointestinal tract (9 cases); blood malignancies accounted for 45% of cases (lymphoid disorder in 9, myelodysplastic syndrome in 11, chronic myelogenous leukemia in 1). In our patients, logistic regression analysis failed to demonstrate differences between those with and without malignancy, except for a higher frequency of rheumatic involvement in the former group (60% vs 30%; p = 0.01). The initial response to steroid treatment was good in 92% of 40 assessable patients, and the vasculitis course mirrored that of malignancy in only 2 patients. Regarding the outcome of TA, no differences were observed in our patients with and without malignancy. CONCLUSION: Concurrent malignancy in TA is not a rare finding, being observed in up to 7.4% of the cases. Solid malignancies and hematological disorders, especially myelodysplastic syndromes, may represent precipitating factors for development of TA, which infrequently run a paraneoplastic course. Patients with and without malignancy seem almost indistinguishable regarding features and outcome of TA. Physicians who care for patients with TA should be mindful of this potential association, even in typical cases.

Serological pattern 'anti-hepatitis B core alone' in HIV or hepatitis C virus-infected patients is not fully explained by hepatitis B surface antigen mutants.

We determined the frequency of hepatitis B virus (HBV) occult infection and studied S gene mutations in HIV or hepatitis C virus-co-infected patients with persistent pattern 'anti-hepatitis B core alone'. HBV DNA was particularly frequent in HIV-positive patients. Sequencing of the S gene showed that only two HIV-infected patients harboured mutants in the major hydrophilic loop; the absence of hepatitis B surface antigen detection could not be explained by diagnostic escape mutants.

No evidence for a putative involvement of platelet-activating factor in systemic lupus erythematosus without active nephritis.

BACKGROUND: Platelet-activating factor (PAF) seems to be implicated in systemic lupus erythematosus (SLE) patients with associated renal diseases. AIMS: In this study, we ensured the role of PAF in SLE patients without renal complications. METHODS: Blood PAF and acetylhydrolase activity, plasma soluble phospholipase A(2), and the presence of antibodies against PAF were investigated in 17 SLE patients without active nephritis and in 17 healthy controls. RESULTS: Blood PAF levels were not different (p=0.45) between SLE patients (6.7+/-2.8 pg/ml) and healthy subjects (9.6+/-3.1 pg/ml). Plasma acetylhydrolase activity (the PAF-degrading enzyme) was significantly (p=0.03) elevated in SLE patients (57.8+/-6.4 nmol/min/ml) as compared with controls (37.9+/-2.6 nmol/min/ml). Plasma soluble phospholipase A(2) (the key enzyme for PAF formation) was not different (p=0.6) between SLE patients (59.1+/-5.1 U/ml) and controls (54.7+/-2.4 U/ml). Antibodies against PAF were detected only in 3/17 SLE patients. Flow cytometry analysis did not highlight PAF receptors on circulating leukocytes of SLE patients. CONCLUSION: This clinical study highlights no evidence for a putative important role of PAF in SLE patients without active nephritis.