Flow cytometric analysis of duodenal intraepithelial lymphocytes (celiac lymphogram): A diagnostic test for celiac disease

Celiac disease (CD) diagnosis in adults and certain cases of children mainly relies on the assessment of histopathological features in duodenal biopsies. However, none of the histological findings that characterize CD are pathognomonic. This, in addition to the clinical heterogeneity of the disease and the presence of seronegative forms, makes the diagnosis of CD still a challenge. A hallmark of the celiac mucosa is the elevated number of TCRγδ intraepithelial lymphocytes (IEL) in the epithelium, which may remain increased even long after gluten withdrawal. Active disease is also characterized by the decreased CD3- IEL subset. The use of flow cytometry enables a precise cell counting and phenotyping, allowing the ascertainment of both TCRγδ+ and CD3- IEL subsets, what is known as the "IEL lymphogram." Although determination of this lymphogram has become a routine evaluation tool in numerous hospitals, standardization of the technical method will guarantee an accurate performance in order to become a pivotal technique for CD diagnosis. Here we describe the protocol to process duodenal biopsies in order to obtain the IELs from the mucosa and to characterize lymphocyte populations by flow cytometry to obtain the IEL lymphogram.

A framework for assessing the potential for a double dividend from a policy-induced reduction in alcohol consumption on the economy

OBJECTIVES

Tax policies targeted at reducing alcohol consumption are typically understood to be associated with economic losses, including in alcohol production and trade sectors. This study sought to determine whether the overall effect of reduced alcohol consumption might be positive once improvements in productivity associated with reduced alcohol-related consumption are considered.

STUDY DESIGN

This study used Computable General Equilibrium economic modelling.

METHODS

An economic modelling framework was developed for Scotland, which considered the fiscal and economic impacts of alcohol taxation and the economy-wide impacts. Simulation of hypothetical alcohol taxes and improvements in labour productivity calibrated on losses due to absenteeism and presenteeism in Scotland in 2017.

RESULTS

The long-run impacts of a five pence increase in taxation alone produce negative economic impacts on jobs and Gross Domestic Product in Scotland (1189 jobs and £71.12 million). These effects are reduced by half - but remain negative - when the revenues from such policy are recycled to the economy through government spending. A small improvement in labour productivity - equivalent to 4.95% of the total productivity gap from absenteeism and presenteeism estimated for Scotland - would be sufficient to turn the economic consequence non-negative.

CONCLUSIONS

The overall macroeconomic impact of policies targeted at alcohol consumption should include consideration of the potential productivity effect and that impact studies that do not include such mechanisms are likely to overstate the negative economic impacts of alcohol policies.

POS0847 MYOSITIS AUTOANTIBODIES DETECTED BY LINE BLOT IMMUNOASSAY: CLINICAL ASSOCIATIONS AND CORRELATION WITH ANTIBODY TITERS

Background

Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of autoimmune diseases (AID) characterized by muscle inflammation and weakness, often accompanied with other organ involvement, such as skin rash or interstitial lung disease (ILD). Myositis specific (MSA) and myositis associated antibodies (MAA) can be detected in approximately 60% of patients with IIM. Besides, antibody titers have been suggested to be related with diagnostic accuracy, although it has not been widely studied. MSA are considered to be exclusive of patients with IIM, whilst MAA can occur in IIM and other systemic autoimmune diseases, nevertheless, most of the studies are focused exclusively on IIM patients.

Objectives

The aim of this study is to assess the relationship between MSA/MAA and diagnosis (including IIM and other AID), and to explore the impact of antibody titers in diagnostic accuracy.

Methods

We retrospectively reviewed all the serum samples obtained from patients tested for MSA/MAA between 01/01/2018 and 31/12/2020 in the Immunology department of Ramón y Cajal University Hospital (Spain). These antibodies were tested by line blot immunoassay (LIA) (EUROLINE Autoimmune Inflammatory Myopathies 16 Ag, Euroimmun, Lübeck, Germany). Positivity was stablished according to absorbance titer and adjusted by positive control of each test (arbitrary units, AU). True positive (TP) MSA and MAA were defined as those patients with IIM or AID with phenotypes expected of that MSA/MAA, according to the available information. The patients that did not have a phenotype compatible with that antibody were regarded as false positive (FP). Statistical analysis was carried out using IBM SPSS statistics version 22.

Results

We analyzed 130 positive samples which corresponded to 130 patients, 85 were women and mean age was 55.08 years. 44 patients (33.8%) were classified as IIM, 43 (33.1%) as AID, and 43 (33.1%) as non-IIM/AID. Among these 130 patients, 164 MSA/MAA were detected. 83 (50.6%) positive MSA/MAA were regarded as TP, and 81 (49.4%) as FP (positive predictive value [PPV] 50.6%). Antibodies regarded as TP had a higher antibody titer compared to FP (49,19 AU vs 26,96 AU, p<0.001). This difference was statistically significant for MSA and MAA when analysed separately (Figure 1). FP antibodies were associated with negative ANA and low titer ANA (p<0.001). Multiple positive antibodies (antibodies included in samples that were positive for > 1 MSA/MAA) were more frequently FP in comparison with isolated positive MSA/MAA (p<0.001).

Figure 1.

Autoantibody titers comparison between false positives and true positives. MSA=myositis specific antibody, MAA=myositis associated antibody, FP=false positive, TP=true positive

Conclusion

In this study we confirm that FP results using LIA are relatively frequent, and are associated with lower titer MSA/MAA, negative ANA, lower titer ANA, and with multiple positive MSA/MAA within one sample.

References

[1]Betteridge Z, Tansley S, Shaddick G, et al (2019) Frequency, mutual exclusivity and clinical associations of myositis autoantibodies in a combined European cohort of idiopathic inflammatory myopathy patients. J Autoimmun 101:48–55. https://doi.org/10.1016/j.jaut.2019.04.001

[2]Cavazzana I, Fredi M, Ceribelli A, et al (2016) Testing for myositis specific autoantibodies: Comparison between line blot and immunoprecipitation assays in 57 myositis sera. J Immunol Methods 433:1–5. https://doi.org/10.1016/j.jim.2016.02.017

[3]Tansley SL, Li D, Betteridge ZE, McHugh NJ (2020) The reliability of immunoassays to detect autoantibodies in patients with myositis is dependent on autoantibody specificity. Rheumatol (United Kingdom) 59:2109–2114. https://doi.org/10.1093/rheumatology/keaa021

[4]Mahler M, Betteridge Z, Bentow C, et al (2019) Comparison of Three Immunoassays for the Detection of Myositis Specific Antibodies. Front Immunol 10:848. https://doi.org/10.3389/fimmu.2019.00848

Disclosure of Interests

None declared

Effect of mobile voice calls on treatment initiation among patients diagnosed with tuberculosis in a tertiary care hospital of Puducherry: A randomized controlled trial

Objective

In India, about one third of tuberculosis (TB) patients diagnosed at tertiary hospitals are missed during a referral to peripheral health institutes for treatment. To address this, we assessed whether mobile voice call reminders to TB patients after diagnosis at a tertiary hospital decrease the proportion of "pretreatment loss to follow-up" (PTLFU), compared with the conventional paper-based referral.

Design

A two-group parallel-arm randomized controlled trial was conducted.

Setting

The study was conducted in a tertiary care hospital at Puducherry, South India.

Participants

All newly diagnosed TB patients, both pulmonary and extrapulmonary, who were referred for treatment from the selected tertiary care hospital and possessed a mobile phone were eligible to participate. The participants were enrolled between March 2015 and June 2016 and were randomized to study groups using the block randomization with allocation concealment.

Intervention

The participants in the intervention arm received standardized mobile voice calls reminding them to register for anti-TB treatment on the second and seventh day after referral in addition to the conventional paper-based referral received by the control group.

Primary outcomes

Patients not started on anti-TB treatment within 14 days of referral were considered as PTLFU. The outcome of PTLFU was ascertained through phone calls made on the 14^th day after referral. The intention-to-treat analysis was used, and the proportion of PTLFU in the study groups and the risk difference with 95% confidence interval (CI) were calculated.

Results

Of the 393 patients assessed for eligibility, 310 were randomized to the intervention (n = 155) and control (n = 155) arms. In the intervention arm, 14 (9%) out of 155 were PTLFU compared with 28 (18%) of the 155 patients in the control arm. The absolute risk difference was 9% (95% CI [1.5, 16.6], P = 0.01).

Conclusion

Mobile voice call reminder to patients is a feasible intervention and can reduce PTLFU among referred TB patients.

Investigation of groundwater and soil quality near to a municipal waste disposal site in Silchar, Assam, India

Unscientific management of municipal solid waste is one of the direct sources of contamination in developing countries, such as India. The present investigation carried out during Oct–Dec 2019 attempts to assess the parameters, such as quality of groundwater and soil along three depths (0–5, 5–15 and 15–30 cm), in proximity to a dumping site in Silchar, a rapidly evolving city of North-East India. Standard protocols of soil and water quality assessments were carried out. The pH values of the surface soils were found to be slightly acidic. Decrease in acidity with increasing depth was observed in the study site. The relative abundance of the analyzed elements at all soil depths was Zn > Fe > Ni > Cu > Cr. Weak correlation between the concentration of Cu, Fe and Zn, and the bulk density of the soil highlighted the micronutrient status of the soil. The impact of the nearby dumpsite on trace element contamination is indicated by the ‘extremely contaminated’ status of the soils with respect to geo-accumulation index. Majority of the groundwater samples exhibited pH levels below the desired limits, making it unfit for consumption by local communities. While Fe, Cu and Ni levels in groundwater samples exceeded the guideline values, Cr and Zn concentrations were found to be within limits except one sample. Principal Component Analysis of the observed data was carried out to ascertain the predominant sources of contamination. The observations indicate the negative impacts of nearby dumpsite on environmental parameters, such as groundwater and soil quality, as highlighted in this research.

E-health, community housing and nursing interprofessional clinic for equity

Problem

From a focus on transmittable diseases, attention to prevention and promotion has become a priority since 2011. Influenced by the Political Declaration of the High-level Meeting on the Prevention and Control of Non-communicable Diseases and The Rio Declaration on Social Determinants of Health, many countries across the world have identified targets aiming at chronic diseases prevention, preventable death and reduced morbidity. Individual behavior changes remain a challenge for health practitioners. Shanghai Declaration suggests that health literacy is a critical determinant for healthy choices and decisions.

Description

A healthy living program has been developed and offered in partnership between local public health and university Laval. We present the case of the community housing Mimosa du Quartier and its preventative nursing clinic. Eight-week Preventative circles and e-prevention interventions from kinesiologist, nutritionist and nurses are explored. IPads were provided to families and we used REACT technology.

Results

Discussion on e-health relevance, feasibility and impact is proposed. Program description, personalised action plan using SMART goals, health literacy and prevention gains are revealed. Relevance, feasibility and perceived impact are discussed. Learning about the user's experience, we can improve the telehealth program in support of continuity of care within the homes of families. This strategy is key to self-management and empowerment Lessons. Health promotion with e-prevention is strategic for sustainable family health. Combining strategies can improve outcomes. This pilot research shows promising results and practical considerations are given to the importance of the relational and alliance aspect of the care relationship even through technology use, to digital literacy capabilities, to family's motivation and engagement and finally to the advantages provided by the technology use.

Key messages

E-health prevention is an innovative avenue to fight chronic disease. Increased engagement in self-management leads to equity and less adverse outcomes for vulnerable families.

FRI0250 “ARE MYOSITIS ANTIBODIES SPECIFIC FOR IDIOPATHIC INFLAMMATORY MYOPATHY DIAGNOSIS?” CLINICAL CORRELATION OF A COHORT OF PATIENTS POSITIVE FOR MYOSITIS ANTIBODIES

Background:

Idiopathic inflammatory myopathies (IIM) are a group of immune-mediated diseases characterized my muscle weakness, skin rash and systemic involvement. Myositis-specific antibodies (MSA) and myositis-associated antibodies (MAA) play a major role in IIM diagnosis, classification and prognosis. Nevertheless, MSA/MAA testing is not standardized and there very few studies addressing their relationship with other diseases.

Objectives:

To describe a cohort of patients tested positive for MSA/MAA, and to explore it´s relationship with IIM and other autoimmune diseases.

Methods:

We retrospectively review all the serum samples obtained from patients tested for MSA/MAA during 2019 in the Immunology department of Ramón y Cajal University Hospital (Madrid, Spain). These antibodies were tested by specific immunoblot (EUROLINE: Autoimmune Inflammatory Myopathies 16 Ag) with highly purified MSA/MAA. Positivity was stablished according to absorbance titer and adjusted by positive control of each test (arbitrary units, AU). Patients were diagnosed with IIM according to their clinician diagnosis. Diagnosis and classification were confirmed by an independent rheumatologist (JL) according to current understanding of IIM classification.

Results:

Three-hundred-seventy-five samples were tested for MSA during the study period. Two-hundred-seventy-nine were negative for all antibodies tested. Ninety-six samples were positive for one or more MSA/MAA, corresponding to 74 patients (11 patients had 2 different samples). Forty-nine (66.2%) of the patients who tested positive were female and 25 (33.8%) were male. Mean age was 58.65 years. Only 22 patients (29.7%) had a confirmed diagnosis of IIM, 24 (32.4%) had a diagnosis of other autoimmune disease, and 11 (14.9%) were diagnosed with interstitial lung disease (ILD) (Figure 1). Six ILD patients had anti-PM-Scl or anti-Ku antibodies, which are associated with scleroderma or overlap-CTD myositis, nevertheless, they remained classified as ILD as no other features were described in this group.

Seventeen patients were positive for more than 1 MAA or MSA, including 14 patients positive for anti Ro-52. Antibody titer was higher in the IIM group compared to non-myositis group (59.59 vs 44.16, p=0.015). Anti Mi-2 was positive in 4 ILD without any other myositis features, and high titer anti-SRP (n=4, mean 59.75 AU) was found in primary biliary cirrhosis (PBC) patients. Additionally, 5 patients positive for antiJo-1 using ELIA (Thermo Fisher) were diagnosed with antisynthetase syndrome. IIM diagnosis and its relationship with antibody titer is represented in table 1.

Table 1.

Autoantibody titer according to diagnosis.

Antibody (Number of patients)Number of samplesIIMIIM antibody titer (AU)Non-IIMNon-IIM antibody titer (AU)Other AI diseasesAnti Ro-52Anti Jo-1 (n=1)11 (100%)92.70-01 (100%)Anti PL-7 (n=8)113 (37.5%)29.595 (62.5%)25.595 (62.5%)2 (25%)Anti PL-12 (n=3)21 (33.3%)53.952 (66.6%)69.971 (33.3%)2 (50%)Anti EJ (n=1)11 (100%)99.460-01 (100%)Anti OJ (n=2)40-2 (100%)23.041 (50%)0Anti Ku (n=14)193 (21.4%)107.2511 (78.6%)31.855 (35.7%)0Anti Tif1gamma (n=5)63 (60%)40.122 (40%)23.841 (20%)0Anti NXP2 (n=2)30-2 (100%)13.991 (50%)1 (50%)Anti Mi2 (n=12)173 (25%)48.659 (75%)26.674 (33.3%)0Anti SAE (n=1)10-1 (100%)1800Anti MDA5 (n=2)32 (100%)30.5401 (50%)1 (50%)Anti SRP (n=9)124 (44.4%)42.695 (55.6%)68.165 (55.5%)2 (22.2%)Anti PM-Scl75 and PM-Scl100 (n=2)21 (50%)68.61 (50%)36.6700Anti PM-Scl75 (n=8)10016.268 (100%)22.723 (37.5%)1 (12.5%)Anti PM-Scl100 (n=4)50-4 (100%)23.622 (50%)0

Conclusion:

Only 28.7% of the patients that were MAA/MSA positive had a diagnosis of IIM. Other autoimmune diseases and ILD were commonly found in this group of MSA/MAA positive patients.

References:

[1]Damoiseaux J, Vulsteke JB, Tseng CW, Platteel ACM, Piette Y, Shovman O, et al. Autoantibodies in idiopathic inflammatory myopathies: Clinical associations and laboratory evaluation by mono- and multispecific immunoassays. Vol. 18, Autoimmunity Reviews. Elsevier B.V.; 2019. p. 293–305.

Disclosure of Interests:

None declared

FRI0582 GM-CSF PRODUCED BY CD4+ T CELLS AS A MARKER OF CLINICAL REMISSION IN PATIENTS WITH RHEUMATOID ARTHRITIS TREATED WITH TNF INHIBITORS

Background:

According to the EULAR recommendations, the therapeutic target in patients with RA should be remission (REM). However, no more than 50% of the patients treated with TNF inhibitors (TNFi) attains this outcome. Previous investigations suggested the peripheral blood mononuclear cells (PBMC) as markers associated with the TNFi treatment success1,2. Granulocyte-monocyte colony-stimulating factor (GM-CSF) plays a relevant role in the pathogenesis of rheumatoid arthritis (RA) because it promotes the macrophage differentiation, survival and activation3.

Objectives:

To analyse the intracellular cytokine production by PBMC and its association with REM attainment after 6 months (m) of TNFi treatment in patients with RA.

Methods:

This was a prospective bi-center pilot study including 36 patients with RA. PBMC were isolated from patients at baseline and after 6m of treatment with TNFi and cryopreserved until studied. Intracellular cytokine production by PBMC was stimulated in the presence of 2µg/mL brefeldin as follow: monocytes were stimulated with 20ng/mL LPS during 4h; and simultaneously lymphocytes were stimulated with 50ng/mL phorbol 12-myristate 13-acetate (PMA) and 750ng/mL ionomycin during 4h at 37°C. To identify IL-10-producing B cells, PBMC were pre-incubated with 3µg/mL of CpG oligonucleotide during 20h at 37°C prior to stimulation in presence of 2µmol/L monensin. Intracellular cytokine production (TNFα, IL6, GM-CSF, IL10) by the different cell subsets (monocytes, CD4+and CD8+T cells, naïve and memory B cells) was analysed by flow-cytometry. Clinical activity at baseline and after 6m was assessed by DAS28. REM was defined as DAS28≤2.6 at 6m. The association between REM and the change in cytokine production (Δ, 6m-0m) by each PBMC subset was analysed through univariable and multivariable logistic regression models.

Results:

Seventy-eight percent of the patients were female. After 6m of TNFi treatment, 47% patients attained REM. Univariable analyses was performed to investigate the association between REM and the baseline variables. Male sex (OR: 12.6; 95% CI: 1.35-117.57; p=0.03) and having lower baseline DAS28 (OR: 0.4; 95% CI: 0.19-0.85; p=0.02) were independently associated with attaining REM after 6m of TNFi. In the multivariable analysis, only being male (OR: 19.7; 95% CI: 1.4-273.9; p=0.03) remained independently associated with REM after 6m of treatment. Therefore, further analyses were adjusted by sex. Decreased production of GM-CSF by CD4+T cells percentage was found after 6m of TNFi treatment in REM patients (0m: 6.07%; 6m: 3.87%; p=0.007) while no-REM patients did not show differences with the baseline (0m: 3.70%; 6m: 3.75%; p=0.9). The decrease was significantly associated with attaining REM (OR: 0.56; 95% CI: 0.33-0.95; p: 0.03). No significant association was found between any other analysed intracellular cytokine produced by the different PBMC subsets and REM.

Conclusion:

GM-CSF intracellular production by CD4+T cells was significantly decreased by TNFi treatment only in patients who attained REM. Therefore, our results suggest that GM-CSF production by CD4+T cells may be a useful marker of REM to TNFi in RA.

References:

[1] Sobrino C, et al. Ann Rheum Dis. 2019; 78 (S2): A1665.

[2] Hernández-Breijo B, et al. Ann Rheum Dis. 2019; 78 (S2): A711.

[3] Avci AB, et al. Clin Exp Rheumatol. 2016; 34 (S98), 39-44.

Figure. 1:

Association between the change in intracellular cytokine production (Δ, 6m-0m) by each PBMC subset and REM. Adjusted logistic regression analyses were performed for each cytokine.

Acknowledgments:

ISCIII (PI16/00474; PI16/01092)

Disclosure of Interests:

Borja Hernández-Breijo: None declared, Chamaida Plasencia: None declared, Carlota García-Hoz: None declared, Cristina Sobrino: None declared, Victoria Navarro-Compán Consultant of: Abbvie, Lilly, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, MSD, Lilly, Novartis, Pfizer, UCB, ANA MARTÍNEZ-FEITO: None declared, Israel Nieto-Gañán: None declared, Paloma Lapuente-Suanzes: None declared, Javier Bachiller-Corral: None declared, Gemma Bonilla: None declared, Cristina Pijoan Moratalla: None declared, Garbiñe Roy: None declared, Mónica Vázquez Díaz: None declared, Alejandro Balsa Grant/research support from: BMS, Roche, Consultant of: AbbVie, Gilead, Lilly, Pfizer, UCB, Sanofi, Sandoz, Speakers bureau: AbbVie, Lilly, Sanofi, Novartis, Pfizer, UCB, Roche, Nordic, Sandoz, Luisa María Villar: None declared, DORA PASCUAL-SALCEDO Grant/research support from: Pfizer, Novartis & Progenika, Speakers bureau: Pfizer, Merck, Novartis, Takeda, Menarini & Grifols, Eulalia Rodríguez-Martín: None declared

Surface Activities of a Lipid Analogue Room-Temperature Ionic Liquid and Its Effects on Phospholipid Membrane

There are great efforts of synthesizing imidazolium-based ionic liquids (ILs) for developing new antibiotics as these molecules have shown strong antibacterial activities. Compared to a single-hydrocarbon-chained IL, the lipid analogues (LAs) with two chains are more effective. In the present study, the LA molecule ^MeIm(COOH)^Me(Oleylamine)Iodide has been synthesized and its surface activities along with the effectiveness in restructuring of a model cellular membrane have been quantified. The molecule is found to be highly surface active as estimated from the area-pressure isotherm of a monolayer of the molecules formed at the air-water interface. The X-ray reflectivity (XRR) studies of a monolayer dip-coated on a hydrophilic substrate have shown the structural properties of the layer which resembles to those of unsaturated phospholipids. The LA molecules are observed to fluidize a phospholipid bilayer formed by the saturated lipid 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). At a lower surface pressure, the lipid monolayer of DPPC has exhibited a thickening effect at a low concentration of added LA and a thinning effect at higher concentration. However, at a high surface pressure of the monolayer, the thickness is found to decrease monotonically. The in-plane pressure-dependent interaction of LA molecules with model cellular membrane and the corresponding perturbation in the structure and physical properties of the membrane may be linked to the strong lysing effect of these types of molecules.

High-throughput Cos-Seq screen with intracellular Leishmania infantum for the discovery of novel drug-resistance mechanisms

Increasing drug resistance towards first line antimony-derived compounds has forced the introduction of novel therapies in leishmaniasis endemic areas including amphotericin B and miltefosine. However, their use is threatened by the emergence and spread of drug-resistant strains. In order to discover stage-dependent resistance genes, we have adapted the Cos-Seq approach through the introduction of macrophage infections in the pipeline. A L. infantum intracellular amastigote population complemented with a L. infantum cosmid library was submitted to increasing concentrations of miltefosine, amphotericin B and pentavalent antimonials in experimental infections of THP-1 cells. For each step of selection, amastigotes were extracted and cosmids were isolated and submitted to next-generation sequencing, followed by subsequent gene-enrichment analyses. Cos-Seq screen in amastigotes revealed four highly enriched loci for antimony, five for miltefosine and one for amphotericin B. Of these, a total of seven cosmids were recovered and tested for resistance in both promastigotes and amastigotes. Candidate genes within the pinpointed genomic regions were validated using single gene overexpression in wild-type parasites and/or gene disruption by means of a CRISPR-Cas9-based approach. This led to the identification and validation of a stage-independent antimony-resistance gene (LinJ.06.1010) coding for a putative leucine rich repeat protein and a novel amastigote-specific miltefosine-resistance gene (LinJ.32.0050) coding for a member of the SEC13 family of WD-repeat proteins. This study further reinforces the power of Cos-Seq approach to discover novel drug-resistance genes, some of which are life-stages specific.

•

The Cos-Seq led to the discovery of several new genomic regions selected with drugs.

•

This work led to the validation of novel drug-resistance genes in Leishmania.

•

Gene LinJ.06.1010 is involved in antimony resistance in both life stages of the parasite.

•

Gene LinJ.32.0050 is involved in miltefosine resistance in amastigotes.

•

The amastigote screen is labour intensive but complements screens in promastigotes.

Are partners of HIV-infected people being tested for HIV? A mixed-methods research from Gujarat, India

Setting: Four selected antiretroviral therapy (ART) centres of Gujarat State, India, which accounts for 8% of the human immunodeficiency virus (HIV) burden in India. Objectives: 1) To assess the proportion of people living with HIV (PLHIV) whose partners were not tested for HIV; 2) to assess sociodemographic and clinical characteristics of index cases associated with partner testing; and 3) to understand perceived facilitators and barriers to partner testing and make suggestions on how to improve testing from the perspective of the health-care provider. Design: A mixed-method design with a quantitative phase that involved reviewing the programme records of married PLHIV enrolled during 2011-2015, followed by a qualitative phase of key informant interviews. Results: Of 3884 married PLHIV, 1279 (33%) did not have their partners tested for HIV. Factors including index cases being male, illiterate, aged >25 years, belonging to key populations, substance use and being in advanced clinical stages were more likely to be associated with partner non-testing. Non-disclosure of HIV status (due to fear of marital discord) and lack of awareness and risk perception were the key barriers to testing. Conclusion: One third of PLHIV did not have their partners tested for HIV. Several factors were identified as being associated with the non-testing of partners, and solutions were explored that need to be implemented urgently if we are to achieve the 90-90-90 targets and end HIV.

MDR-TB in Puducherry, India: reduction in attrition and turnaround time in the diagnosis and treatment pathway

Setting: A mixed-methods operational research (OR) study was conducted to examine the diagnosis and treatment pathway of patients with presumptive multidrug-resistant tuberculosis (MDR-TB) during 2012-2013 under the national TB programme in Puducherry, India. High pre-diagnosis and pre-treatment attrition and the reasons for these were identified. The recommendations from this OR were implemented and we planned to assess systematically whether there were any improvements. Objectives: Among patients with presumptive MDR-TB (July-December 2014), 1) to determine pre-diagnosis and pre-treatment attrition, 2) to determine factors associated with pre-diagnosis attrition, 3) to determine the turnaround time (TAT) from eligibility to testing and from diagnosis to treatment initiation, and 4) to compare these findings with those of the previous study (2012-2013). Design: This was a retrospective cohort study based on record review. Results: Compared to the previous study, there was a decrease in pre-diagnosis attrition from 45% to 24% (P < 0.001), in pre-treatment attrition from 29% to 0% (P = 0.18), in the TAT from eligibility to testing from a median of 11 days to 10 days (P = 0.89) and in the TAT from diagnosis to treatment initiation from a median of 38 days to 19 days (P = 0.04). There is further scope for reducing pre-diagnosis attrition by addressing the high risk of patients with human immunodeficiency virus and TB co-infection or those with extra-pulmonary TB not undergoing drug susceptibility testing. Conclusion: The implementation of findings from OR resulted in improved programme outcomes.

Different Mutations in a P-type ATPase Transporter in Leishmania Parasites are Associated with Cross-resistance to Two Leading Drugs by Distinct Mechanisms

Leishmania infantum is an etiological agent of the life-threatening visceral form of leishmaniasis. Liposomal amphotericin B (AmB) followed by a short administration of miltefosine (MF) is a drug combination effective for treating visceral leishmaniasis in endemic regions of India. Resistance to MF can be due to point mutations in the miltefosine transporter (MT). Here we show that mutations in MT are also observed in Leishmania AmB-resistant mutants. The MF-induced MT mutations, but not the AmB induced mutations in MT, alter the translocation/uptake of MF. Moreover, mutations in the MT selected by AmB or MF have a major impact on lipid species that is linked to cross-resistance between both drugs. These alterations include changes of specific phospholipids, some of which are enriched with cyclopropanated fatty acids, as well as an increase in inositolphosphoceramide species. Collectively these results provide evidence of the risk of cross-resistance emergence derived from current AmB-MF sequential or co-treatments for visceral leishmaniasis.

Screening for diabetes among presumptive tuberculosis patients at a tertiary care centre in Pondicherry, India

SETTING

Designated microscopy centre (DMC) attached to a tertiary care centre in Pondicherry, India.

OBJECTIVES

To determine 1) the proportion of diabetes mellitus (DM), 2) the additional yield of newly diagnosed DM cases, and 3) the number needed to screen (NNS) to find a new case of DM among presumed TB patients.

DESIGN

An institution-based cross-sectional study was carried out among 650 presumed TB patients attending the DMC. Capillary blood glucose was measured using fasting blood sugar and/or oral glucose tolerance test, and evaluated according to the World Health Organization criteria.

RESULTS

Of 570 presumed TB patients evaluated for DM, 121 (21.2%) were found to be diabetic. Of these, 69 were previously known to have DM, while 52 were newly diagnosed. The additional yield of diabetes was 43%. The NNS to detect a new case of DM was 11; among those aged >40 years, the NNS was 9.3, and among smear-positive TB patients it was 4.6.

CONCLUSION

One fifth of the presumed TB patients had diabetes, and nearly half of these patients were newly diagnosed. Opportunity screening of presumed TB patients for DM in routine care will help in early detection of diabetes and pre-diabetes.

Inactivation of the cytosolic and mitochondrial serine hydroxymethyl transferase genes in Leishmania major

Leishmania has two serine hydroxylmethyl transferase (SHMT) genes, one coding for a cytosolic and the other for a mitochondrial enzyme. Trypanosoma cruzi has only the gene coding for the cytosolic enzyme and Trypanosoma brucei has no SHMT. We tested whether these genes were dispensable for growth in Leishmania major. By gene inactivation we succeeded in generating three cells lines one without the cytosolic cSHMT, one without the mitochondrial mSHMT, and finally one L. major line without any SHMT. SHMT is thus dispensable for growth of Leishmania in rich medium. The ability of the various shmt null mutants to grow in defined medium was tested and the growth of the shmt null mutant was dependent on the presence of serine. Overall this work has shown that SHMT is dispensable for Leishmania growth but it may be necessary when growing in environments poor in serine.

MDR-TB screening in a setting with molecular diagnostic techniques: who got tested, who didn't and why?

SETTING

The Revised National Tuberculosis Control Programme, Puducherry, India, which has facilities for molecular diagnostic technique.

OBJECTIVE

To determine pre-diagnostic and pre-treatment attrition among presumptive multidrug-resistant tuberculosis (MDR-TB) patients and reasons for attrition.

METHODS

In this mixed-methods study, the quantitative component consisted of retrospective cohort analysis through record review of all presumptive MDR-TB patients recorded between October 2012 and September 2013. The qualitative component included in-depth interviews with key informants involved in programmatic management of drug-resistant tuberculosis services.

RESULTS

Of 341 eligible presumptive MDR-TB patients, pre-diagnostic and pre-treatment attrition was respectively 45.5% (155/341) and 29% (2/7). Patients with extra-pulmonary TB (RR = 2.3), those with human immuno-deficiency and TB co-infection (RR = 1.7), those registered during October-December 2012 (RR = 1.3) and those identified from primary/secondary health centres (RR = 1.8) were less likely to be tested. Themes that emerged during the analysis of the qualitative data were 'lack of a systematic mechanism to track referrals for culture and drug susceptibility testing', 'absence of courier service to transport sputum', 'lack of knowledge and ownership among staff of general health system', 'shortage of diagnostic kits' and 'patient non-adherence'.

CONCLUSION

Despite the introduction of molecular diagnostic techniques, operational issues in MDR-TB screening remain a concern and require urgent attention.

Roles of Rad51 paralogs for promoting homologous recombination in Leishmania infantum

To achieve drug resistance Leishmania parasite alters gene copy number by using its repeated sequences widely distributed through the genome. Even though homologous recombination (HR) is ascribed to maintain genome stability, this eukaryote exploits this potent mechanism driven by the Rad51 recombinase to form beneficial extrachromosomal circular amplicons. Here, we provide insights on the formation of these circular amplicons by analyzing the functions of the Rad51 paralogs. We purified three Leishmania infantum Rad51 paralogs homologs (LiRad51-3, LiRad51-4 and LiRad51-6) all of which directly interact with LiRad51. LiRad51-3, LiRad51-4 and LiRad51-6 show differences in DNA binding and annealing capacities. Moreover, it is also noteworthy that LiRad51-3 and LiRad51-4 are able to stimulate Rad51-mediated D-loop formation. In addition, we succeed to inactivate the LiRad51-4 gene and report a decrease of circular amplicons in this mutant. The LiRad51-3 gene was found to be essential for cell viability. Thus, we propose that the LiRad51 paralogs play crucial functions in extrachromosomal circular DNA amplification to circumvent drug actions and preserve survival.

Genome-wide stochastic adaptive DNA amplification at direct and inverted DNA repeats in the parasite Leishmania

The human parasite Leishmania uses adaptive gene rearrangements and amplification involving repeated sequences on a genome-wide scale as one strategy to adapt to a changing environment.

Gene amplification of specific loci has been described in all kingdoms of life. In the protozoan parasite Leishmania, the product of amplification is usually part of extrachromosomal circular or linear amplicons that are formed at the level of direct or inverted repeated sequences. A bioinformatics screen revealed that repeated sequences are widely distributed in the Leishmania genome and the repeats are chromosome-specific, conserved among species, and generally present in low copy number. Using sensitive PCR assays, we provide evidence that the Leishmania genome is continuously being rearranged at the level of these repeated sequences, which serve as a functional platform for constitutive and stochastic amplification (and deletion) of genomic segments in the population. This process is adaptive as the copy number of advantageous extrachromosomal circular or linear elements increases upon selective pressure and is reversible when selection is removed. We also provide mechanistic insights on the formation of circular and linear amplicons through RAD51 recombinase-dependent and -independent mechanisms, respectively. The whole genome of Leishmania is thus stochastically rearranged at the level of repeated sequences, and the selection of parasite subpopulations with changes in the copy number of specific loci is used as a strategy to respond to a changing environment.

Variations in the copy number of DNA segments account for a substantial amount of genome diversity of most organisms. DNA amplification, a contributor to copy number variation, can occur in response to various stresses or after altered growth conditions, leading to extensive and often reversible genetic variation. DNA amplification in the parasite Leishmania occurs outside the normal chromosomes and arises by DNA rearrangements involving homologous repeated sequences. We show here that such repeated sequences are widespread in the Leishmania genome and that most of the Leishmania genome is subject to stochastic gene rearrangements mediated by these low-copy repeat sequences. Thus, although cells in the population have a common core genome, many individual cells will differ from the rest of the population by carrying one or more distinct extrachromosomal amplicon. Upon selection with either drugs or culture conditions, a subpopulation can emerge where the amplicon copy number per cell increases, and this clone of cells can then expand to dominate the population. We propose that Leishmania uses adaptive gene amplification at a genome-wide scale as one strategy to adapt to a changing environment.

Effect of biochanin-a or testosterone on liver-tumors induced by a combined treatment of den and fission neutron in bcf1 mice

To determine the biological effect of biochanin A, miso or NaCl and sexual influence of testosterone on liver tumor induction, male and female BCF1 mice were i.p. injected once with DEN at a dose of 5 mug/g body weight at 15 days of age. In order to shorten the latency of liver tumor occurrence, the whole body of mice were exposed to 2 Gy of Cf-252 fission neutrons at four weeks of age. Three days later, female mice were surgically ovariectomized and given the various doses of testosterone melted into a cholesterol pellet. Male mice were fed on 10 ppm, 20 ppm biochanin A, 10% miso or 2% NaCl supplemented diet for 8 weeks (from 21 to 28 weeks of age) and 4 weeks (from 32 to 36 weeks of age). All mice were sacrificed at 40 weeks of age. Multiplicity of liver tumors was expressed in four different size ranges by <2, 3-5, 6-10 and >10 mm2. Incidence of liver tumors in all experimental groups except in group 1 at 20 weeks were observed at 100%. Average tumor size and multiplicity were smaller at 20 weeks compared to those of 40-week groups. Male groups fed 20 ppm biochanin A and 2% NaCl had an increase in body weight with significant difference from control by p<0.01. Liver weights were more-or-less the same in all groups except an increase was seen in the group of 20 ppm biochanin A (p<0.01). In female groups, both 0.2 mg and 1 mg of testosterone administration resulted in an increase of tumor multiplicities and a decrease of liver weight compared to that of control group with significant differences. In both male and female groups, majority of liver tumor sizes were in the range of 3-5 mm2. Tumor multiplicities and size in less than 2 mm2 in biochanin A groups, 10% miso and 2% NaCl decreased significantly from control group. These findings suggest that 15-20 weeks is the time in which 1-2 mm2 size of liver tumors start to appear. Among others, biochanin A is a component of miso. The potent anti-tumorigenic effect of dietary miso for mouse liver tumorigenesis may be strenghtened by a combination of factors such as the presence of Biochanin A, protease inhibitors and various fermented enzymes.

Interactions between BRCA2 and RAD51 for promoting homologous recombination in Leishmania infantum

In most organisms, the primary function of homologous recombination (HR) is to allow genome protection by the faithful repair of DNA double-strand breaks. The vital step of HR is the search for sequence homology, mediated by the RAD51 recombinase, which is stimulated further by proteins mediators such as the tumor suppressor BRCA2. The biochemical interplay between RAD51 and BRCA2 is unknown in Leishmania or Trypanosoma. Here we show that the Leishmania infantum BRCA2 protein possesses several critical features important for the regulation of DNA recombination at the genetic and biochemical level. A BRCA2 null mutant, generated by gene disruption, displayed genomic instability and gene-targeting defects. Furthermore, cytological studies show that LiRAD51 can no longer localize to the nucleus in this mutant. The Leishmania RAD51 and BRCA2 interact together and the purified proteins bind single-strand DNA. Remarkably, LiBRCA2 is a recombination mediator that stimulates the invasion of a resected DNA double-strand break in an undamaged template by LiRAD51 to form a D-loop structure. Collectively, our data show that LiBRCA2 and LiRAD51 promote HR at the genetic and biochemical level in L. infantum, the causative agent of visceral leishmaniasis.

Genetic polymorphisms and drug susceptibility in four isolates of Leishmania tropica obtained from Canadian soldiers returning from Afghanistan

BACKGROUND

Cutaneous leishmaniasis (CL) is a vector-borne parasitic disease characterized by the presence of one or more lesions on the skin that usually heal spontaneously after a few months. Most cases of CL worldwide occur in Southwest Asia, Africa and South America, and a number of cases have been reported among troops deployed to Afghanistan. No vaccines are available against this disease, and its treatment relies on chemotherapy. The aim of this study was to characterize parasites isolated from Canadian soldiers at the molecular level and to determine their susceptibility profile against a panel of antileishmanials to identify appropriate therapies.

METHODOLOGY/PRINCIPAL FINDINGS

Parasites were isolated from skin lesions and characterized as Leishmania tropica based on their pulsed field gel electrophoresis profiles and pteridine reductase 1 (PTR1) sequences. Unusually high allelic polymorphisms were observed at several genetic loci for the L. tropica isolates that were characterized. The drug susceptibility profile of intracellular amastigote parasites was determined using an established macrophage assay. All isolates were sensitive to miltefosine, amphotericin B, sodium stibogluconate (Pentostam) and paromomycin, but were not susceptible to fluconazole. Variable levels of susceptibility were observed for the antimalarial agent atovaquone/proguanil (Malarone). Three Canadian soldiers from this study were successfully treated with miltefosine.

CONCLUSIONS/SIGNIFICANCE

This study shows high heterogeneity between the two L. tropica allelic versions of a gene but despite this, L. tropica isolated from Afghanistan are susceptible to several of the antileishmanial drugs available.

Genome sequencing of the lizard parasite Leishmania tarentolae reveals loss of genes associated to the intracellular stage of human pathogenic species

The Leishmania tarentolae Parrot-TarII strain genome sequence was resolved to an average 16-fold mean coverage by next-generation DNA sequencing technologies. This is the first non-pathogenic to humans kinetoplastid protozoan genome to be described thus providing an opportunity for comparison with the completed genomes of pathogenic Leishmania species. A high synteny was observed between all sequenced Leishmania species. A limited number of chromosomal regions diverged between L. tarentolae and L. infantum, while remaining syntenic to L. major. Globally, >90% of the L. tarentolae gene content was shared with the other Leishmania species. We identified 95 predicted coding sequences unique to L. tarentolae and 250 genes that were absent from L. tarentolae. Interestingly, many of the latter genes were expressed in the intracellular amastigote stage of pathogenic species. In addition, genes coding for products involved in antioxidant defence or participating in vesicular-mediated protein transport were underrepresented in L. tarentolae. In contrast to other Leishmania genomes, two gene families were expanded in L. tarentolae, namely the zinc metallo-peptidase surface glycoprotein GP63 and the promastigote surface antigen PSA31C. Overall, L. tarentolae's gene content appears better adapted to the promastigote insect stage rather than the amastigote mammalian stage.

Down regulation of KMP-11 in Leishmania infantum axenic antimony resistant amastigotes as revealed by a proteomic screen

The therapeutic mainstay against the protozoan parasite Leishmania is still based on the antiquated pentavalent antimonials, but resistance is increasing in several parts of the world. Resistance is now partly understood in laboratory promastigote isolates, but the mechanism leading to drug resistance in amastigote isolates is lagging behind. Here we describe a comparative proteomic analysis of a genetically related pair of antimonial-sensitive and -resistant Leishmania infantum axenic amastigote strains. The proteomics screen has highlighted a number of proteins differentially expressed in the resistant parasite. The expression of the protein argininosuccinate synthetase (ARGG) was increased in the drug resistant mutant while a decrease in the expression of the kinetoplastid membrane protein (KMP-11) correlated with the drug resistance phenotype. This proteomic screen highlighted several novel proteins that are putatively involved in resistance to antimonials.

Glucantime-resistant Leishmania tropica isolated from Iranian patients with cutaneous leishmaniasis are sensitive to alternative antileishmania drugs

Cutaneous leishmaniasis (CL) is a major health problem in endemic areas of Iran. The pentavalent antimony (SbV) based drug Glucantime is the first line of treatment for CL in Iran, but recently SbV-resistant Leishmania tropica isolates derived from unresponsive patients were reported. We show in this study that these resistant parasites are cross-resistant to the other SbV-containing drug Pentostam and at least for one isolate also to amphotericin B. However, these resistant isolates were shown to be sensitive to miltefosine and paromomycin. The latter two drugs could thus be useful alternatives for the treatment of leishmaniasis in Iran even for SbV-resistant isolates.

Role of ABC transporter MRPA, gamma-glutamylcysteine synthetase and ornithine decarboxylase in natural antimony-resistant isolates of Leishmania donovani

OBJECTIVES

The resistance of clinical isolates of Leishmania donovani to sodium antimony gluconate (SAG), the mainstay of treatment in Indian visceral leishmaniasis, has become a critical issue in India. The present work investigates the mechanism of resistance to SAG in parasites isolated from patients who are unresponsive to SAG.

METHODS AND RESULTS

Susceptibility to SAG as determined in vitro with intracellular amastigotes correlated well with the clinical response. The ABC transporter gene MRPA was amplified in resistant field isolates as part of an extrachromosomal circle. Co-amplification of the pterin reductase gene (PTR1) and MRPA suggests amplification of the H locus in SAG-resistant isolates. Amplification of MRPA was correlated to increased RNA as determined by real-time PCR. MRPA is an ABC-thiol transporter, and cysteine and glutathione were increased in the resistant isolates. Ornithine decarboxylase (a rate limiting enzyme in polyamine biosynthesis), and gamma-glutamylcysteine synthetase (a rate limiting enzyme in glutathione biosynthesis), the two building blocks of the main cellular thiol trypanothione, were overexpressed in some of the resistant isolates.

CONCLUSIONS

A variety of resistance mechanisms to SAG, most of them consistent with a model based on the study of resistance in vitro, were present in clinical isolates from the same geographical region.

HPLC detection of plasma concentrations of diclofenac in human volunteers administered with povidone-ethylcellulose based experimental transdermal matrix-type patches

By developing a high-performance liquid chromatography (HPLC) method, we estimated the blood concentrations of diclofenac in human volunteers administered with the transdermal patches prepared with povidone-ethylcellulose and oral diclofenac tablets. Drug-excipient interaction studies were done using the FTIR technique. The external morphology of the prepared patch before and after application to human skin was analyzed with scanning electron microscopy. FTIR studies revealed that there was no predominant interaction between the drug and polymers. In vivo studies revealed that the average concentrations of drug in plasma were 376, 1562, 2953, 2902, 2864, and 2948 ng/ml after 2, 4, 8, 24, 30, and 48 h from patches each containing 50 mg of diclofenac diethylamine, respectively, and the mean concentrations of drug in plasma after the oral administration of marketed tablet containing 50 mg diclofenac sodium were 383.7, 2569, 3693.5, 162.5, and 55.3 ng/ml at 2, 4, 8, 24, and 30 h after oral administration. Values of Cmax were 3693.5 after oral administration and 2953.8 ng/ml in the case of transdermal application. From this study, we have achieved the sustained blood level of diclofenac from the experimental patches along with an analytical method based on HPLC to determine the diclofenac blood level.

Role of the ABC transporter MRPA (PGPA) in antimony resistance in Leishmania infantum axenic and intracellular amastigotes

Antimonial compounds are the mainstay for the treatment of infections with the protozoan parasite Leishmania. We present our studies on Leishmania infantum amastigote parasites selected for resistance to potassium antimonyl tartrate [Sb(III)]. Inside macrophages, the Sb(III)-selected cells are cross-resistant to sodium stibogluconate (Pentostam), the main drug used against Leishmania. Putative alterations in the level of expression of more than 40 genes were compared between susceptible and resistant axenic amastigotes using customized DNA microarrays. The expression of three genes coding for the ABC transporter MRPA (PGPA), S-adenosylhomocysteine hydrolase, and folylpolyglutamate synthase was found to be consistently increased. The levels of cysteine were found to be increased in the mutant. Transfection of the MRPA gene was shown to confer sodium stibogluconate resistance in intracellular parasites. This MRPA-mediated resistance could be reverted by using the glutathione biosynthesis-specific inhibitor buthionine sulfoximine. These results highlight for the first time the role of MRPA in antimony resistance in the amastigote stage of the parasite and suggest a strategy for reversing resistance.

Inactivation of the Leishmania tarentolae pterin transporter (BT1) and reductase (PTR1) genes leads to viable parasites with changes in folate metabolism and hypersensitivity to the antifolate methotrexate

The protozoan parasite Leishmania is a folate and pterin auxotroph. The main biopterin transporter (BT1) and pterin reductase (PTR1) have already been characterized in Leishmania. In this study, we have succeeded in generating a BT1 and PTR1 null mutant in the same Leishmania tarentolae strain. These cells are viable with growth properties indistinguishable from wildtype cells. However, in response to the inactivation of BT1 and PTR1, at least one of the folate transporter genes was deleted, and the level of the folylpolyglutamate synthetase activity was increased, leading to increased polyglutamylation of both folate and methotrexate (MTX). Secondary events following gene inactivation should be considered when analyzing a phenotype in Leishmania. The BT1/PTR1 null mutant is hypersensitive to MTX, but in a step-by-step fashion, we could induce resistance to MTX in these cells. Several resistance mechanisms were found to co-exist including a reduced folate and MTX accumulation, demonstrating that cells with no measurable biopterin uptake but also greatly reduced folate uptake are viable, despite their auxotrophy for each of these substrates. The resistant cells have also amplified the gene coding for the MTX target dihydrofolate reductase. Finally, we found a marked reduction in MTX polyglutamylation in resistant cells. These studies further highlight the formidable ability of Leishmania cells to bypass the blockage of key metabolic pathways.