Clinical impact and prognosis of cryoglobulinemia and cryofibrinogenemia in systemic sclerosis

INTRODUCTION

An association of systemic sclerosis (SSc) with cryoglobulin and/or cryofibrinogenemia has been described. However, clinical, biological, morphological and prognostic implications are unknown. The objective of this study was to describe the phenotype and evaluate the prognosis of cryoglobulinemia and/or cryofibrinogenemia in the progression of SSc.

MATERIALS AND METHODS

Patients were included from the Systemic Scleroderma Toulouse Cohort (SSTC), between June 1, 2005 and May 31, 2018, and underwent a measurement of a cryoglobulin and/or cryofibrinogen in immunology laboratory at the Toulouse University Hospital Center. Patients with and without cryoglobulinemia >50 mg/l and patients with and without cryofibrinogenemia were compared to identified the impact of cryoprcipitate on the phenotype. Mortality based on cryoprecipitate was explored.

RESULTS

166 patients were included in the study. 43.3% and 46.6% had a cryoglobulinemia >50 mg/l and cryofibrinogenemia, respectively. Cryoglobulin >50 mg was not associated with microvascular damage. Cryoglobulin does not influence the phenotype. 5-and 10-years survival were 97.6% and 88.8% respectively in patients with cryoglobulinemia >50 mg/l versus 91.9% and 78.4% in patients without cryoglobulin>50 mg/l. 10-years survival was better for patients with cryoglobulinemia >50 mg/l (log-rank 0.0363). Cryofibrinogenemia was not associated with neoplasia, any clinical (in particular ischemic damage), biological or morphological features. Cryofibrinogenemia had no influence on the mortality of these patients.

CONCLUSION

Cryoglobulinemia and cryofibrinogenemia are frequent in SSc. The presence of cryoprecipitate (cryoglobulin or cryofibrinogen) not influence the phenotype and has not associated with a poor survival.

Cryofibrinogenemia: a marker of severity of cryoglobulinemic vasculitis

BACKGROUND

Cryofibrinogenemia is frequently associated with cryoglobulinemia. The aim of this study was to determine the characteristics associated with the presence of cryofibrinogenemia in patients with cryoglobulinemic vasculitis.

METHODS

This was a single-center retrospective study that included patients with cryoglobulinemic vasculitis who were tested for cryofibrinogen at a tertiary referral center between January 1, 2011 and December 31, 2012. Twenty-nine patients fulfilled the CryoVas (cryoglobulinemic vasculitis) Survey criteria for cryoglobulinemic vasculitis. Eighteen patients had a detectable cryofibrinogen (CF-positive) and 11 had no detectable cryofibrinogen (CF-negative). Median cryoglobulin levels were 89 ± 129 mg/L in the CF-positive group and 68 ± 82 mg/L in the CF-negative group (P = .32). Median cryofibrinogen level was 70 ± 174 mg/L. Clinical manifestations were similar in both groups. Cancers and hematological disorders were more frequent among CF-positive patients (39% vs 0%, P = .026). Levels of alpha-1 and alpha-2 globulinemia were higher in the CF-positive group. Cryofibrinogenemia ≥ 100 mg/L was associated with cryoglobulinemic vasculitis (odds ratio [OR] 2.86; 95% confidence interval [CI], 1.06-7.73) in cryoglobulinemic patients. Presence of cryofibrinogenemia was associated with use of corticosteroids, immunosuppressants, or plasmapheresis in cryoglobulinemic vasculitis patients (OR 22.7; 95% CI, 2.02-256.44).

CONCLUSIONS

Our results strongly suggest that presence of cryofibrinogenemia is associated with a more severe phenotype among patients with cryoglobulinemic vasculitis.

Blood concentrations of hydroxychloroquine and its desethyl derivative correlate negatively with the percentage of CD45RO+ cells among CD4+ lymphocytes in hydroxychloroquine-treated lupus patients

The objective of the study was to investigate the influence of the blood concentrations of hydroxychloroquine ([HCQ]) and its derivative desethylhydroxychloroquine ([DHCQ]) on lymphocyte activation or differentiation in HCQ-treated lupus patients. We studied the correlations between [HCQ], [DHCQ], and the frequency of various lymphocyte subsets in 58 HCQ-treated lupus patients (mean HCQ dose: 4.93 +/- 1.58 mg/kg/day; mean duration of the disease: 122 +/- 64 months). [HCQ] and [DHCQ] were determined by high-performance liquid chromatography (HPLC). Lymphocyte markers were studied by flow cytometry using monoclonal anti-CD3, -CD4, -CD8, -CD25, -DR, -CD45RA, -CD45RO, -CD19, -CD38, and -CD86 antibodies. sIL2-R serum concentrations were measured by enzyme-linked immunosorbent assay (ELISA). [HCQ] and [DHCQ] were 599.9 ng/mL (median: 529.5; range: 55-1935) and 353.43 (median: 286 ng/mL; range: 118-1090). In a multiple regression analysis, [HCQ] and [DHCQ] were associated with the HCQ prescribed dose in mg/kg/day (P = 0.0002 and P = 0.03) and with compliance to the treatment (P = 0.004 and P = 0.03). We found a negative correlation between [HCQ], [DHCQ], and the CD45RO+ cell frequency among CD3+CD4+ cells (P = 0.03 and P = 0.007, respectively). Other lymphocyte subset markers (LSMs) and sIL2-R concentrations were not significantly associated with [HCQ] or [DHCQ]. In the multiple regression analysis, CD45RO+ expression was negatively influenced by [HCQ] (P = 0.005), and positively influenced by smoking habits (P = 0.005) and age (P = 0.005). Similar results were found in the multivariate model including [DHCQ]. Disease activity and taking more than 10 mg/day of corticosteroids or an immunosuppressive drug did not influence CD45RO+ expression. Lupus patients had less CD3+CD4+CD45RO+ cells than controls (P = 0.03). In lupus patients, HCQ and DHCQ may alter the generation or the blood circulation of CD4+CD45RO+ lymphocytes in a concentration-dependent pattern.

Biological weapons

Smallpox virus eradication was one of the greatest successes of the 20th century. Moreover, the quest to combat its use in biological warfare, has fueled efforts to understand residual immune memory and to develop new animal models by the scientific community. Although the literature is full of animal studies of vaccinia virus infection, continuing efforts have helped to increase our knowledge regarding humoral and cellular memory to non-persistent pathogens and to study factors that might influence further vaccination strategies in humans. In addition, the potent immunostimulatory action of poxvirus vectors has led to development and evaluation of new-generation vaccine candidates, which will be discussed in this review.

Analysis of CCR5, CCR2, CX3CR1, and SDF1 polymorphisms in HIV-positive treated patients: impact on response to HAART and on peripheral T lymphocyte counts

Although polymorphisms of chemokine genes (SDF1, stromal cell-derived factor-1 and RANTES, regulated on activation, normal T cell expressed and secreted) and chemokine-receptor genes (CCR5, CCR2, CX(3)CR1) were shown to be associated with sensitivity to HIV infection and untreated HIV disease progression, their association with the response to highly active antiretroviral therapy (HAART) remains unclear. To explore the possible influence of such polymorphisms on the evolution of AIDS in treated patients, we have studied SDF1-3'A, CCR5Delta32, CCR2-64I, CX(3)CR1-249I, and CX(3)CR1-280M polymorphisms in HIV-infected patients under HAART (n = 169). We studied the evolution of plasma virus load and peripheral T lymphocyte counts in these patients up to 3 years after the initiation of HAART. We observed that some of the genetic polymorphisms studied had an impact on the evolution of these two parameters. After 1 year of HAART, patients with a virological response (undetectable plasma HIV-1 RNA) have a higher frequency of the homozygous SDF1-3'A genotype than other patients (p = 0.005). Similarly, patients with a CD4 increase of over 200/mm(3) from baseline after 1 year of HAART display higher frequencies of homozygous SDF1-3'A (p = 0.035) and homozygous CX(3)CR1-280M genotypes (p = 0.04) than other patients. Moreover, we showed that the CX(3)CR1- 280M allele was associated with higher peripheral CD4+ T cell counts not only in HIV+ patients but also in healthy controls (p = 0.003).

Immunomodulatory effect of human adipose tissue-derived adult stem cells: comparison with bone marrow mesenchymal stem cells

Like mesenchymal stem cells from bone marrow (BM-MSCs), adipose tissue-derived adult stem cells (ADAS cells) can differentiate into several lineages and present therapeutical potential for repairing damaged tissues. The use of allogenic stem cells can enlarge their therapeutical interest, provided that the grafted cells could be tolerated. We investigate here, for the first time, the immunosuppressive properties of ADAS cells compared with the well-characterized immunosuppressive properties of BM-MSCs. ADAS cells did not provoke in vitro alloreactivity of incompatible lymphocytes and, moreover, suppressed mixed lymphocyte reaction (MLR) and lymphocyte proliferative response to mitogens. The impairment of inhibition when ADAS cells and BM-MSCs were separated from lymphocytes by a permeable membrane suggests that cell contact is required for a full inhibitory effect. Hepatocyte growth factor is secreted by both stem cells but, similar to interleukin-10 and transforming growth factor-beta (TGF-beta), the levels of which were undetectable in supernatants of MLR inhibited by ADAS cells or BM-MSCs, it did not seem implicated in the stem cell suppressive effect. These findings support that ADAS cells share immunosuppressive properties with BM-MSCs. Therefore, ADAS cell-based reconstructive therapy could employ allogenic cells and because of their immunosuppressive properties, ADAS cells could be an alternative source to BM-MSCs to treat allogenic conflicts.

FOXP3 mRNA levels are decreased in peripheral blood CD4+ lymphocytes from HIV-positive patients

The impact of HIV infection on regulatory CD4(+)CD25(high) (Treg) lymphocyte subpopulations was evaluated by FOXP3 quantitative reverse transcriptase polymerase chain reaction and by flow cytometry. FOXP3 mRNA was quantified in peripheral blood mononuclear cells or purified CD4(+) lymphocytes from HIV(+) lymphopenic patients. Patients were distributed among clinical stages A, B, and C and received highly active antiretroviral therapy. The frequency of CD4(+)CD25(high) lymphocytes, measured by flow cytometry, was decreased in HIV patients (n = 38) compared with the group of uninfected subjects (n = 39). FOXP3 mRNA levels were found decreased in HIV patients (n = 25) compared with controls (n = 17) when expression of CD3gamma or beta-actin but not that of TATA box binding protein 1 was used for data normalization. Our results are compatible with a decrease of the Treg lymphocytes during HIV infection. The consequences of a Treg decrease are discussed in the context of immunologic anomalies observed during HIV infection.

Decrease of Lewis frequency in HIV-infected patients: possible competition of fucosylated antigens with HIV for binding to DC-SIGN

We explored the impact of human ABO glycosyltransferase and Lewis and secretor fucosyltransferase polymorphisms in HIV infection. We found that, compared with healthy blood donors, HIV-infected patients display a significant decrease in Le(a-b+) phenotype frequencies. We showed that HIV binding on DC-SIGN-transduced Jurkat cells was inhibited by fucosyl bovine serum albumin. Our results suggest a slight protective effect of Lewis b antigen on HIV infection, possibly by the competition of Lewis antigens with HIV for binding to DC-SIGN.

A simple method to optimize peripheral blood mononuclear cell preparation from cynomolgus monkeys and improve mixed lymphocyte reactions

INTRODUCTION

The standard Ficoll-Hypaque method used to isolate peripheral blood mononuclear cells (PBMC) gives very variable results when used with cynomolgus monkey blood. We have improved the method by using special cell processing tubes (CP-tubes), originally developed for clinical use.

METHODS

Blood samples were collected from cynomolgus monkeys and processed for PBMC preparation using either the classical Ficoll-Hypaque method or CP-tubes following various centrifugation protocols. The preparations were compared according to their cellular content as well as their response in the mixed lymphocyte reaction (MLR).

RESULTS

Good PBMC separation was achieved in >90% of samples by centrifugation of blood samples in CP-tubes for 40-45 min at 1650 x g and 20 degrees C. For the remaining samples, poor PBMC separation was probably due to low corpuscular hemoglobin concentrations (< 28 g/dl), but this could be rectified by using one to two additional centrifugations. The PBMC preparations thus obtained showed lower red blood cell (RBC) and polymorphonuclear (PMN) cell contamination, reacted well to mitogen and showed improved MLR stimulation indices vs. standard Ficoll-Hypaque-PBMC-derived preparations. The inhibitory effect of Cyclosporine-A (CsA) was within the low nanomolar range with both methods.

DISCUSSION

These results demonstrate that the use of CP-tubes is a practical way of improving PBMC separation and MLR responses with cynomolgus monkey blood.

[Thymus function and autoimmunity]

PURPOSE

Thymus is the site of T-cell development and is essential for the induction of self-tolerance, by deletion of autoreactive T lymphocytes (negative selection) and by generation of regulatory T cells. Defect of the selection mechanism of both types of lymphocytes lead to autoimmune diseases.

CURRENT KNOWLEDGE AND KEY POINTS

Elimination of potentially self-reactive T cells in the thymus requires the intrathymic expression of ubiquitous and "tissue-specific" antigens. Some thymic antigen expressions are dependent on AIRE expression. Mutations in the AIRE gene that are associated with the absence of autoantigen expression in the thymus, defects in the peptide presentation or in apoptosis can allow autoreactive T cells to escape negative selection, and are associated with autoimmune diseases. Recent data are now available concerning the thymic selection of autoreactive regulatory T cells. The Foxp3 gene was recently shown to be predominantly expressed in regulatory T cells and could be a more specific marker of regulatory T cells than phenotypic markers.

FUTURE PROSPECTS AND PROJECTS

Animal models show that regulatory T cells injection or intrathymic inoculation of antigen lead to immunological tolerance in autoimmunity and transplantation. These novel strategies could be used in human.

Virological exploration of individuals with discordant HIV screening tests

Screening for HIV infection can use many algorithms. When two different HIV antibody assays are used, discordant results may occur. To discriminate between HIV seroconversion, HIV variant infection and false positive reactivity, 30 consecutive subjects with two discordant HIV antibody-screening assays were extensively investigated for HIV infection. No subject had HIV seroconversion or reached HIV seropositivity criteria after a follow-up of 3 months. By contrast 36% became HIV negative by the use of both HIV screening assays. p24 Antigen, HIV-1 RNA, HIV-1 DNA, HIV-2 DNA assays and HIV isolation by sensitive culture were unable to identify HIV infection in the 30 subjects with discordant HIV screening assays. The data suggest that the use of two HIV screening assays increase false-positive HIV results without increasing clinical sensitivity. To compliment follow-up of HIV screening, early testing for HIV RNA could be useful to identify or eliminate a recent infection.

Polymorphism of human and primate RANTES, CX3CR1, CCR2 and CXCR4 genes with regard to HIV/SIV infection

Among genes that influence human susceptibility to HIV (human immunodeficiency virus) infection or AIDS (acquired immunodeficiency syndrome) progression, chemokine-receptor and chemokine genes were extensively studied because of their role as HIV co-receptors or co-receptor competitors, respectively. We have studied in non-human primates (chimpanzee, gorilla, gibbon, orang-utan, crab-eating and rhesus macaque, baboon and marmoset) the RANTES, CCR2 and CX3CR1 gene sequences in regions surrounding human mutations that were associated with susceptibility to HIV or AIDS progression: RANTES G-403A and C-28G, CCR2 V64I, CX3CR1 V249I and CX3CR1 T280M. Among these five dimorphisms, only RANTES G-403A is observed in one of the eight primate species studied here (gibbon). This suggests that these mutations appeared recently in humans and probably do not account for variable HIV/SIV disease progression in primates. It is noteworthy that chimpanzees, which are naturally resistant to HIV-1- and HIV-2-induced AIDS, do not have the human mutations associated with delayed disease progression. Inter-species and intra-species polymorphic positions are observed in primates and we discuss the potential impact of these mutations on HIV/SIV disease progression. Particularly, we identified polymorphisms in old-world monkey (OWM) genes, and it could be of great importance to analyse the possible association between these polymorphisms and disease progression in OWM species that are currently used in research for HIV vaccine and therapy.

Virological and immunological effects of salvage therapy following treatment interruption and a shift in HIV-1 resistance genotype

The circulating human immunodeficiency virus type 1 (HIV-1) population of patients in whom many prior therapy regimens have failed often undergo a shift from a drug-resistant virus to a wild-type virus following interruption of treatment. This study analyses the virological and immunological effects of salvage therapy following treatment interruption and a shift from a drug-resistance genotype. Twenty-one HIV-1 infected patients who had genotype reversion by population-based sequencing after 3 months of treatment interruption were given a new salvage regimen consisting of 3-5 drugs selected according to their treatment history. Seven (33%) of 21 patients who had fewer than 200 HIV-1 RNA copies/ml until month 12 were defined as virological responders. Four patients were transient responders and 10 were nonresponders. The virological responders were more frequently CDC group A and had higher CD4 + T lymphocyte counts at the time of treatment resumption. The peripheral blood T CD4 + and T CD8 + lymphocyte populations of the patients declined significantly during treatment interruption. Only virological responders showed significant increases in their CD4 + T lymphocyte count 12 months after treatment resumption and these counts rapidly returned to pre-interruption baseline values in most of these patients. Treatment interruption could be useful for optimising salvage therapy for patients previously given many failing regimens. However, controlled trials are needed to assess the clinical benefit of this strategy.

Mutations of the 3' untranslated region of the SDF1 gene in apes and monkeys: potential impact on sensitivity to AIDS induced by lentiviruses

The comparison of the stromal cell-derived factor-1 (SDF1) gene 3' untranslated region (3'UTR) of four great ape and four monkey species with their human counterparts shows that the human SDF1-3'A mutation is present in primate species that are the most susceptible to lentivirus-induced AIDS and is absent in species that are particularly resistant to lentivirus-induced AIDS. The results enlighten the possible relationship between SDF1-3'UTR polymorphism and sensitivity to AIDS.

Chlamydia pneumoniae induces interleukin-10 production that down-regulates major histocompatibility complex class I expression

Recently, it was demonstrated that CD8(+) T cells are important for the response against Chlamydia pneumoniae. By use of the human monocytic cell line U937 and human monocytes taken from peripheral blood, we investigated the effect of infection on various molecules critical for CD8(+) T cell function. A strong secretion of interleukin (IL)-10 by infected cells was observed, together with an inhibited expression of major histocompatibility complex (MHC) class I antigens, but without significant alteration of tumor growth factor-beta secretion or MHC class II expression. Recombinant IL-10 added to uninfected U937 cells decreased the expression of MHC class I, whereas blocking antibodies to IL-10 and its receptor abolished the C. pneumoniae-induced inhibition of MHC class I expression. Analysis of our data provides evidence that IL-10 secretion induced by C. pneumoniae infection of monocytic cells down-regulates the expression of MHC class I molecules and thereby might reduce the presentation of bacterial epitopes by MHC. This would decrease the ability of CD8(+) T cells to eliminate infected cells.

Shift in HIV resistance genotype after treatment interruption and short-term antiviral effect following a new salvage regimen

OBJECTIVE

To investigate the changes in genotypic drug-resistance pattern, plasma HIV RNA and CD4 cell count after treatment interruption and assess the short-term antiviral effect of a new salvage regimen.

DESIGN

Prospective study of 38 patients with multiple failing regimens who had completely stopped all medication for 3 months before a three to five-drug regimen was reintroduced according to clinical guidelines.

METHODS

Patients were tested for HIV resistance before and after treatment interruption by population-based sequencing and clonal analysis of selected patients.

RESULTS

Discontinuation of therapy for 3 months was associated with a median increase in HIV RNA of 0.4 log10 and a median decrease in CD4 cell count of 43 x 10(6)/l. Sixty-one per cent of patients had a shift from the drug-resistant genotype to a predominantly wild-type genotype. The patients significantly likely to show genotype reversion were those in Centers for Disease Control groups A or B, who had been exposed to few drugs, had a low plasma HIV RNA, or a high CD4 cell count. The only independent factor predicting genotype reversion was the clinical stage. The median change in plasma HIV RNA at month 3 after treatment reintroduction was -2.3 log10 copies/ml in patients who had genotype reversion compared with -0.6 log10 copies/ml in patients without genotype reversion (P = 0.004).

CONCLUSION

Suspending treatment for 3 months after multiple failures could be a suitable strategy for optimizing salvage therapy provided it is instituted early, before the HIV disease becomes too advanced.

[Neonatal type 1 pneumococcal meningitis and maternal septicemia]

The most common organisms in neonatal meningitis are group B streptococcus and Gram negative enteric bacteriae. Although Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae are the most frequent causes of meningitis in infancy and childhood, they are uncommon in newborns. We report one case of neonatal meningitis and maternal septicemia.