Selective CD8 cell reduction by SARS-CoV-2 is associated with a worse prognosis and systemic inflammation in COVID-19 patients

The lymphopenia exhibited in patients with COVID-19 has been associated with a worse prognosis in the development of the disease. To understand the factors associated with a worse evolution of COVID-19, we analyzed comorbidities, indicators of inflammation such as CRP and the ratio of neutrophils/lymphocytes, as well as the count of blood cells with T-lymphocyte subtypes in 172 hospitalized patients with COVID-19 pneumonia. Patients were grouped according to their needs for mechanical ventilation (ICU care) or not. Within the comorbidities studied, obesity was the only associated with greater severity and ICU admission. Both the percentage and the absolute number of neutrophils were higher in patients needing ICU care than non-ICU patients, whereas absolute lymphocyte count, and especially the percentage of lymphocytes, presented a deep decline in critical patients. There was no difference between the two groups of patients for CD4 T-lymphocytes, neither in percentage of lymphocyte nor in absolute number, however for CD8 T-cells the differences were significant for both parameters which were in decline in ICU patients. There was a firm correlation between the highest values of inflammation indicators with the decrease in percentage of CD8 T-lymphocytes. This effect was not seen with CD4 cells. Obesity together with lymphopenia, especially whether preferentially affects to CD8 T- lymphocytes, are factors that can predict a poor prognosis in patients with COVID-19.

Prospective analysis of the factors influencing the antibody response to hepatitis B vaccine in hemodialysis patients

Hepatitis B vaccine is effective in producing protection against hepatitis B virus (HBV) infection in hemodialysis (HD) patients, but the antibody response is variable. To identify those factors implicated in the vaccine response, in a prospective study over a 24-month period, we vaccinated 80 seronegative patients on HD (group A) and monitored clinical, biochemical, and immunologic parameters. The protective immunity acquired by vaccination was compared with that developed through HBV infection in 22 age-matched HD patients (group B). The anti-HBs antibody-seronegative patients followed a four-dose vaccination schedule (0, 1, 2, and 6 months) with 40 microg DNA-recombinant hepatitis B vaccine. One month after vaccination, 77.5% of the patients had seroconverted, and 72.5% achieved high antibody response, whereas 22.5% were nonresponders. Patients aged younger than 40 years seroconverted 100%; those aged 40 to 60 years, 75% (P < 0.01); and patients older than 60 years, 74% (P < 0.001). No differences between responders and nonresponders concerning sex, time on HD, HD dose, nutritional status, hemoglobin level, HD membrane, iPTH level, calcitriol treatment, or number of transfusions during vaccination were found. The presence of other factors, such as recombinant human erythropoietin (rHuEPO) therapy or hepatitis C virus (HCV) infection, did not significantly influence antibody responses to hepatitis B immunization. A greater frequency of DR3 (53.8% v 25.7%, P < 0.05), DR7 (53.8% v 18.6%, P < 0.01), and DQ2 (76.9% v 44.1%, P < 0.05), and a lesser frequency of A2 (7.7% v 37.2%, P < 0.05) were found in nonresponders compared with responders. Eighteen months after vaccination, the analysis showed similar antibody titers but lower seroconversion rates in group A as compared with group B. In conclusion, unresponsiveness to hepatitis B vaccine in HD patients was related to factors such as older age, the presence of DR3, DR7, and DQ2, and the absence of A2 alleles. Although the seroprotection produced by the vaccine was less than that achieved through natural HBV infection, our protocol of vaccination was sufficiently immunogenic and provided lasting protection.

High serum IL-6 values increase the risk of mortality and the severity of pneumonia in patients diagnosed with COVID-19

The clinical presentation of COVID-19 is very heterogeneous, ranging from asymptomatic to severe, which could lead to the need for mechanical ventilation or even death.We analyzed the serum levels of IL-6 in patients with COVID-19 diagnosis and its relationship with the severity of the disease, the need for mechanical ventilation and with patient mortality. We assessed IL-6 in a cohort of 50 patients diagnosed with COVID-19 pneumonia with different degrees of disease severity, and compared it with clinical and laboratory findings. We found higher levels of IL-6 in patients with more severe pneumonia according to CURB-65 scale (p = 0.001), with ICU mechanical ventilation requirements (p = 0.02), and who subsequently died (p = 0.003). Of the clinical and analytical parameters analyzed in the current study, the serum levels of IL-6 was the most effective predictor of disease severity. From the data obtained in ROC curve analysis, we defined a cut-off point for serum IL-6 levels of 35 pg/mL above which both the risk of mortality (OR = 20.00, 95 % CI 4.214-94-912, p = 0.0001) and ICU admission (OR = 12.750, 95 % CI 2,159-75,3,3, p = 0.005) were increased. Starting from blood IL-6 levels 27 out of 50 patients, with high levels and more severe symptoms, were treated with the IL-6 receptor antagonist Tocilizumab. IL-6 serum levels appear to be a useful prognostic biomarker in patients with a diagnosis of COVID-19 pneumonia. A cut-off point of 35 pg/mL could clearly differentiate patients a with more severe disease.

Dopamine in human follicular fluid is associated with cellular uptake and metabolism-dependent generation of reactive oxygen species in granulosa cells: implications for physiology and pathology

STUDY QUESTION

Is the neurotransmitter dopamine (DA) in the human ovary involved in the generation of reactive oxygen species (ROS)?

SUMMARY ANSWER

Human ovarian follicular fluid contains DA, which causes the generation of ROS in cultured human granulosa cells (GCs), and alterations of DA levels in follicular fluid and DA uptake/metabolism in GCs in patients with polycystic ovary syndrome (PCOS) are linked to increased levels of ROS.

WHAT IS KNOWN ALREADY

DA is an important neurotransmitter in the brain, and the metabolism of DA results in the generation of ROS. DA was detected in human ovarian homogenates, but whether it is present in follicular fluid and plays a role in the follicle is not known.

STUDY DESIGN, SIZE AND DURATION

We used human follicular fluid from patients undergoing in vitro fertilization (IVF), GCs from patients with or without PCOS and also employed mathematical modeling to investigate the presence of DA and its effects on ROS.

PARTICIPANTS/MATERIALS, SETTING AND METHODS

DA in follicular fluid and GCs was determined by enzyme-linked immunosorbent assay. GC viability, apoptosis and generation of ROS were monitored in GCs upon addition of DA. Inhibitors of DA uptake and metabolism, an antioxidant and DA receptor agonists, were used to study cellular uptake and the mechanism of DA-induced ROS generation. Human GCs were examined for the presence and abundance of transcripts of the DA transporter (DAT; SLC6A3), the DA-metabolizing enzymes monoamine oxidases A/B (MAO-A/B) and catechol-O-methyltransferase and the vesicular monoamine transporter. A computational model was developed to describe and predict DA-induced ROS generation in human GCs.

MAIN RESULTS AND ROLE OF CHANCE

We found DA in follicular fluid of ovulatory follicles of the human ovary and in GCs. DAT and MAO-A/B, which are expressed by GCs, are prerequisites for a DA receptor-independent generation of ROS in GCs. Blockers of DAT and MAO-A/B, as well as an antioxidant, prevented the generation of ROS (P < 0.05). Agonists of DA receptors (D1 and D2) did not induce ROS. DA, in the concentration range found in follicular fluid, did not induce apoptosis of cultured GCs. Computational modeling suggested, however, that ROS levels in GCs depend on the concentrations of DA and on the cellular uptake and metabolism. In PCOS-derived follicular fluid, the levels of DA were higher (P < 0.05) in GCs, the transcript levels of DAT and MAO-A/B in GCs were 2-fold higher (P < 0.05) and the DA-induced ROS levels were found to be more than 4-fold increased (P < 0.05) compared with non-PCOS cells. Furthermore, DA at a high concentration induced apoptosis in PCOS-derived GCs.

LIMITATIONS, REASONS FOR CAUTION

While the results in IVF-derived follicular fluid and in GCs reveal for the first time the presence of DA in the human follicular compartment, functions of DA could only be studied in IVF-derived GCs, which can be viewed as a cellular model for the periovulatory follicular phase. The full functional importance of DA-induced ROS in small follicles and other compartments of the ovary, especially in PCOS samples, remains to be shown.

WIDER IMPLICATIONS OF THE FINDINGS

The results identify DA as a factor in the human ovary, which, via ROS generation, could play a role in ovarian physiology and pathology. The results obtained in samples from women with PCOS suggest the involvement of DA, acting via ROS, in this condition.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by a grant from DFG MA1080/17-3 and in part MA1080/19-1. There are no competing interests.

DNA polymorphisms and linkage relationship of the human complement component C6, C7, and C9 genes

In this report we describe the linkage between genes encoding human complement components C6, C7, and C9. Polymorphisms have been described at the DNA level for the C7 and C9 genes. We have studied 20 individuals by Southern blot analysis with four C6 cDNA subclones to detect restriction fragment length polymorphisms (RFLPs). We have found a Taq I polymorphism defined by two alleles of 8.0 (C6 H) and 6.0 (C6 L) kilobases (kb). RFLP segregation for the C6, C7, and C9 loci in informative families allowed us to estimate the maximum Lod scores at a recombination fraction of theta = 0.0 (C6-C7), theta = 0.0 (C7-C9), and theta = 0.0 (C6-C9). Significant linkage disequilibrium was found between C6 and C7 and between C7 and C9 loci in directly determined haplotypes of unrelated parents. Data from this study show that the genes encoding the human terminal complement components C6, C7, and C9 define a cluster in the short arm of chromosome 5. We propose that the clusters involving the C8A and C8B and the C6, C7, and C9 genes be referred to as MACI and MACII, respectively.

Expression of Th1, Th2, lymphocyte trafficking and activation markers on CD4+ T-cells of Hymenoptera allergic subjects and after venom immunotherapy

Systemic reactions to Hymenoptera stings can be fatal and represent a reduction in the quality of life. The immune mechanisms involved in venom allergic subjects are barely known. Nevertheless, a shift towards a Th1-type response with an increase in IFNγ levels has been observed after venom immunotherapy (VIT). There is currently no information available about the expression of markers on CD4+ T-cells or their involvement in venom allergy, nor following VIT. For this, we have studied the expression of Th1 and Th2-cell markers, homing receptors and activation markers on CD4+ T-cells of subjects who presented systemic allergic reactions, mainly to Polistes dominulus, and after receiving a 4-month conventional VIT protocol. The markers studied were: CD26 (Th1), CD30 (Th2), CXCR4, CXCR3 (Th1), CCR4 (Th2), CD154 (CD40L), CD152 (CTLA-A), and ICOS. We also determined the IL-4 (Th2) and IFNγ (Th1) intracellular cytokine levels in T-cells and carried out a basophil activation test (BAT). Comparing venom allergic subjects with non-allergic healthy controls, we have found up-regulation of CD26, CXCR4, CXCR3, CD154 and ICOS. Conversely, a down-regulation of CD30, CD154 and CD152 occurred upon immune intervention, whereas the remaining markers were not affected. Equally, VIT has been shown to be effective, as evidenced by the decrease of basophil degranulation and increase of IFNγ levels in T-cells after the fourth month of treatment. These new findings highlight the possible application of these surface molecules as markers to distinguish between symptomatic and asymptomatic subjects sensitized to Hymenoptera venom, as well as revealing information about the immune changes associated with VIT.

Raised expression of cytokine receptor gp130 subunit on peripheral lymphocytes of patients with active lupus. A useful tool for monitoring the disease activity?

The glycoprotein gp130 is a signal traducing subunit with a membrane domain of the IL-6 receptor. In addition, gp130 is shared among the receptors for IL-6 superfamily, and it is critically involved in generating signal transduction through these receptors. The aim of the study is to evaluate the expression of the IL-6 superfamily receptor molecule gp130 on TCD4(+) and B cells in patients with systemic lupus erythematosus (SLE). Surface expression of gp130 on TCD4(+) and B lymphocytes was higher in patients with SLE than in healthy controls (2.79 vs 0.36% and 8.36 vs 0.37%, respectively). Patients with active lupus had higher expression of gp130 (relapsed 15.1%, new onset 26.6%) than stable patients (2.83%), in B-cell subset, but not in TCD4 lymphocytes. An important reduction in the gp130 expression on B lymphocytes was observed when the activity of the disease had disappeared after readjusting its immunosuppressive treatment (20.8-3.8%). In addition, there was significant correlation between the activity of the disease, measured like systemic lupus erythematosus disease activity index score, and surface expression of gp130 in lymphocytes B (r(s) = 0.5880, P = 0.0002). According with our results and roc curve analysis, a cut-off in 6.7% of B cells with gp130 expression were defined, who discriminates active/stable SLE with a sensitivity of 0.93 and a specificity of 0.75. In conclusion, there is an altered expression of gp130 in the patients with SLE. The disease activity as well as immunotherapy seems to influence the pattern of expression of gp130 on B-cell subsets in patients with SLE.

TaqI polymorphism in the complement component C7 gene

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DNA analysis of HLA-DR4B1 subtypes in multiple sclerosis by specific oligonucleotide probes

Conversely to the well-established association of DR2/Dw2 with multiple sclerosis (MS) susceptibility in Caucasoids, several studies have found an association of DR4 in populations from Mediterranean origin. We have studied the distribution of the different DR4B1 subtypes in Spanish MS patients. Oligonucleotide probes were selected in order to type samples amplified by polymerase chain reaction (PCR) from Spanish DR4+ MS patients (25) and controls (28). No DR4B1 subtypes were found to be increased in MS. MS susceptibility linked to DR4 may be due to the presence of shared functional epitopes common to the different HLA-DR4B1 subtypes.

Influence of HLA-DR phenotype on tumor necrosis factor-alpha production in renal-transplant recipients

In healthy subjects, previous studies have demonstrated a great interindividual variability in the ability for tumor necrosis factor-alpha (TNF-alpha) production. The gene for TNF-alpha is closely linked to and located in the major histocompatibility complex (MHC) and it has been suggested that these interindividual differences may be HLA related. Since TNF-alpha is likely to be an important mediator in renal allograft rejection, we investigated the role of HLA antigens on TNF-alpha production rates by peripheral blood mononuclear cells (PBMC) from renal transplant recipients during stable graft function. HLA-DR2-positive recipients showed significantly lower spontaneous TNF-alpha production than DR2-negative patients (p < 0.001). Upon stimulation with OKT3, HLA-DR2-positive patients also showed significantly lower TNF-alpha production than DR2-negative subjects (p < 0.001). HLA-DR3-positive recipients, however, showed significantly higher spontaneous TNF-alpha production than DR3-negative individuals (p < 0.05). These results suggest that differences in TNF-alpha production, both spontaneous and induced, may be due to the expression of certain DR allotypes.

Differential expression of CD30 on CD3 T lymphocytes in patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune systemic disease caused as a result of an imbalance of Th1-/Th2-type cytokines. The soluble form of CD30 (CD30s) released from peripheral blood cells has been described as a marker of active disease in Th2-type immune response as in SLE. However, the expression of CD30 on CD3 T lymphocytes from patients with SLE has not been studied yet. Therefore, we have addressed our study to attempt this issue, studying CD30 expression by flow cytometry on CD3 T lymphocytes and CD4/CD8 subsets in samples from SLE patients mainly with lupus nephritis. In parallel, we have determined the production of the cytokines IL-4 (Th2), IFNγ (Th1), IL-10 and TGFβ by intracellular staining. Differences between positive CD30 T cells in healthy controls and patients with SLE were found, with a higher percentage of CD30-expressing T cells in patients with SLE (P = 0.001). In contrast to healthy controls, CD30 was mainly expressed on CD8 T cells from patients with SLE. The intracellular cytokine staining showed that TGFβ is the main cytokine expressed in CD3 T cells from patients with SLE. In addition to this, we have found a positive correlation between CD30-expressing T cells and IL-4, IFNγ, and immunosuppressive cytokines (IL-10 and TGFβ) (P < 0.05). These results suggest that CD30 could play a role in the pathogenesis of SLE and its expression on CD3 T lymphocytes is not restricted only to Th2-type response.

Serological profile and clinical features of nucleolar antinuclear pattern in patients with systemic lupus erythematosus from southwestern Spain

Nucleolar staining of antinuclear antibodies (ANAs) is not exclusive to patients suffering systemic sclerosis (SSc) since it can occur in other autoimmune diseases, such as systemic lupus erythematosus (SLE). The nucleolar ANA pattern presents a low incidence in patients with SLE, with less than 9% reported in some studies. The significance of nucleolar staining and antinucleolar antibodies (ANoA) in SLE is still unknown, as is its association with clinical manifestations. To address these issues, a case-control study was carried out. Twenty-eight cases of SLE with nucleolar staining were enrolled, as well as 73 controls with no nucleolar staining and different ANA patterns (homogeneous, speckled, and combined homogeneous and speckled). The homogeneous nucleolar pattern was the most frequent (27 out of 28), and in 75% was combined with other ANA patterns. The anti-double stranded DNA antibodies showed no differences between the two groups of patients, nor the auto-antibodies detected by line immunoassay (LIA). However, we have found an increased frequency of anti-PM-Scl antibodies with respect to the controls ( p = 0.02), in addition to the association between Raynaud's phenomenon (RP) and anti-PM-Scl antibodies (OR = 20.72, 95% CI 1.33–323.19, p = 0.03). Moreover, the cases of SLE showed a 7.78-fold increase in the risk of developing cancer (95%, CI 1.85–32.75, p = 0.005) with respect to the control group. Taken together these findings suggest that nucleolar staining represents a comorbidity factor in patients with SLE, although its significance must still be determined.

TaqI polymorphism at the human complement component C9 gene

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Germline repertoire of T-cell receptor beta-chain genes in patients with insulin-dependent diabetes mellitus

We have investigated the genotype and allelic distribution of germline restriction fragment length polymorphisms of the T-cell receptor beta chain, segment C beta, and two variable segments which are in linkage disequilibrium, V beta 8 and V beta 11, in 42 insulin-dependent diabetes mellitus (IDDM) patients and in 51 healthy blood donors used as controls. Recently, several works have reported contradictory results showing or not showing an association between polymorphic alleles of the C beta gene and diabetes type I. We found no significant differences in the allele, genotype, and haplotype distribution of the gene segments studied, between IDDM patients and control populations.

Analysis of the methodology to determine anaerobic toxicity: evaluation of main compounds present in wastewater treatment plants (WWTPs)

The influence of the concentration of biomass on the level of inhibition and anaerobic degradation kinetics in batch systems was studied with toxic compounds that can generate destabilization in the operation of sludge anaerobic digesters. The compounds were grouped in four families; long chain fatty acids, polycyclic aromatic hydrocarbons, linear alkylbenzene sulphonates and organic acids. For the organic acids, there is no effect due to the biomass concentration variation, therefore it is a competitive inhibition; but that doesn't happen with the remaining compounds, where there is a dependence on the complexity of their structure, becoming a non-competitive inhibition. In addition, it was observed that the degradation kinetics is affected, whether diminishing the methane production (polycyclic aromatic hydrocarbons, linear alkylbenzene sulphonates, organics acids) or increasing the initial latency time (long chain fatty acids) without this becoming an obstacle to obtain the maximum methane productions for the latter ones.

SacI polymorphism at the human TCR delta chain constant region (TCRD)

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Agreement of skin test with IL-4 production and CD40L expression by T cells upon immunotherapy of subjects with systemic reactions to Hymenoptera stings

Venom immunotherapy is the only curative intervention for subjects with Hymenoptera venom allergy who suffering systemic reactions upon bee or wasp stings. Venom immunotherapy can restore normal immunity against venom allergens, as well as providing to allergic subjects a lifetime tolerance against venoms. Nevertheless, it is necessary using safety assays to monitoring the development of tolerance in the VIT protocols to avoid fatal anaphylactic reactions. The purpose of this study was to assess the modifications in several markers of tolerance induction in subjects with Hymenoptera venom allergy undergoing immunotherapy. The studies were performed at baseline time and after six month of VIT. Intradermal skin tests, basophil activation tests, specific IgE levels; and the T-cell markers (IL-4 and IFN-γ producing cells; and expression of the surface activation markers CD40L and CTLA-4) were assayed. At six month of immunotherapy all parameters studied had significant alterations. All decreased, except the IFN-γ producing cells. In addition, modifications in intradermal skin test showed a significant correlation with both, CD40L expression on CD4 T lymphocytes (p=0.043) and IL-4 producing T lymphocytes (p=0.012). Neither basophil activation test nor serum levels of sIgE demonstrated any correlation with the immunological parameters studied nor among them. These results suggest that both IL-4 production and CD40L expression could be two good indicators of the beneficial effects of venom immunotherapy which translate into skin tests.

Low Expression of ICAM-1 in Blood Eosinophils in Patients With Active Eosinophilic Esophagitis

BACKGROUND AND OBJECTIVE

Eosinophilic esophagitis (EoE) is a chronic and isolated inflammation of the esophagus characterized by a marked infiltration of eosinophilic leukocytes. Diagnosis and course of the disease are based exclusively on histopathology. Therefore, patients must undergo several esophageal biopsies, implying a risk associated with the procedure and considerable use of resources. Objective: The presence of active circulating eosinophils, which are quantifiable through the expression of specific cellular activation proteins in their membrane, could be consistent with histopathological findings, which are currently the only valid parameters in studies on EoE.

METHODS

The activity of peripheral blood eosinophils from patients with EoE was analyzed by identifying 5 surface molecules (CD69, IL- 5Rα, CD44, ICAM-1, CD63), which are seen to be expressed by the active eosinophils in flow cytometry. The results were compared with the infiltrate of eosinophils present in patients' esophageal biopsies.

RESULTS

ICAM-1 levels decreased significantly in patients with active EoE compared with nonactive EoE patients, allergic patients, and healthy controls. In patients with EoE, an inverse correlation was observed between the number of eosinophils in the esophageal biopsy and the percentage of ICAM-1 expression in peripheral blood eosinophils. No differences were observed for the remaining molecules studied.

CONCLUSION

Expression of ICAM-1 in blood eosinophils could be a useful noninvasive marker for the diagnosis and assessment of patients with EoE.

Partial recovery of SARS-CoV-2 immunity after booster vaccination in renal transplant recipients

The pandemic caused by the SARS-CoV-2 coronavirus has been especially detrimental to patients with end-stage renal disease. History with other vaccines suggests that patients with renal disease may not respond adequately to the SARS-CoV-2 vaccine. The aim of this study is to evaluate the immunity to SARS-CoV-2 mRNA vaccines in renal patients. Post SARS-CoV-2 vaccination first, and after the booster dose, antibodies and cellular immunity were studied in patients on hemodialysis (N = 20), peritoneal dialysis (N = 10) and renal transplantation (N = 10). After the two doses of vaccine, there was an effective immunity in dialysis patients, with 100% seroconversion and 87% detection of cellular immunity (85% in hemodialysis and 90% in peritoneal dialysis). In contrast, in renal transplant recipients there was only 50% seroconversion and cellular immunity was detected in 30% of patients. After the booster dose, all dialysis patients achieved a cellular and antibody immunity, whereas in transplant patients, despite improvement, 20% did not produce antibodies and in 37.5% cellular immunity could not be detected. The mRNA vaccine plus booster performs excellently in dialysis patients, whereas in kidney transplant recipients, despite the booster, complete immunization is not achieved.