The potential application of artificial intelligence in veterinary clinical practice and biomedical research

Artificial intelligence (AI) is a fast-paced technological advancement in terms of its application to various fields of science and technology. In particular, AI has the potential to play various roles in veterinary clinical practice, enhancing the way veterinary care is delivered, improving outcomes for animals and ultimately humans. Also, in recent years, the emergence of AI has led to a new direction in biomedical research, especially in translational research with great potential, promising to revolutionize science. AI is applicable in antimicrobial resistance (AMR) research, cancer research, drug design and vaccine development, epidemiology, disease surveillance, and genomics. Here, we highlighted and discussed the potential impact of various aspects of AI in veterinary clinical practice and biomedical research, proposing this technology as a key tool for addressing pressing global health challenges across various domains.

High Anti-Müllerian Hormone Strongly Correlates with Reproductive Outcomes in Women Undergoing Assisted Reproduction

BACKGROUND

In a retrospective cohort of 881 women with gynecologic and unexplained infertility, we aimed to study the relationship between serum AMH levels and ART outcomes. This retrospective cohort includes 881 infertile women aged 20 - 45 who underwent their first fresh autologous non-preimplantation genetic diagnosis ART cycles between 2012 and 2020.

METHODS

We assessed the correlation between AMH levels and reproductive outcomes among infertile women with different causes of infertility (including endometriosis, polycystic ovary syndrome (PCOS), and unexplained infertility).

RESULTS

We found a strong correlation between high AMH levels and reproductive outcomes independent of age and the cause of infertility in women undergoing ART. In all patients with gynecologic and unexplained infertility, higher AMH correlated with the improved number of oocytes (p < 0.001), MII oocytes (p < 0.001), good-quality embryos (p < 0.001), chemical pregnancy rate (p < 0.001 in women < 37; and p = 0.002 in women over 37), clinical pregnancy rate (p < 0.05), and live birth rate (p = 0.05).

CONCLUSIONS

Serum AMH concentrations can be invaluable for predicting ovarian reserve and reproductive outcomes in young and advanced-age infertile patients undergoing ART. However, it should not be used as the sole predictive marker for disqualifying infertile women from ART treatment. Further large cohort studies are warranted to determine an exact cutoff point for AMH to provide an accurate ART success prediction.

Association of dietary total antioxidant capacity, alternative healthy eating index, and dietary inflammatory index with semen quality in men seeking infertility treatment

Background

Since the association between dietary quality scores and semen quality remains unclear, we carried out a hospital-based cross-sectional study to investigate the association of Dietary Total Antioxidant Capacity (dTAC), Dietary Inflammatory Index (DII), and Alternative Healthy Eating Index (AHEI) scores with semen quality in men seeking infertility treatment.

Methods

This study enrolled 210 men with unexplained or idiopathic infertility. Semen samples were collected and analyzed according to the WHO 2010 criteria. Dietary data was collected using a 168-item semi-quantitative food frequency questionnaire (FFQ) developed for Tehran Lipid and Glucose Study. Multivariable logistic regression models were used to estimate the relationship between dTAC, AHEI, and DII scores with abnormal semen in crude and adjusted models.

Results

There were no significant differences across quartile categories of the dTAC, AHEI, and DII scores regarding semen parameters. There was a trend toward a significant direct association between DII and abnormal semen risk (p = 0.01). Infertile men in the highest quartile of DII had a 2.84 times higher risk of abnormal semen in the crude model (OR: 3.84; 95% CI: 1.64-8.95); such that remained after adjusting for several potential confounders. There was no significant association between dTAC or AHEI and the risk of abnormal semen in infertile men, either before or after adjusting for potential confounders. Total energy (p = 0.05), fat (p = 0.02), saturated fat (p = 0.02), mono-saturated fat (p = 0.009), Thiamine (Vitamin B1) (p = 0.02), Niacin (Vitamin B3) (p = 0.03), Calcium (p = 0.01), and Selenium (p = 0.01) were inversely associated with semen normality.

Discussion

The study suggests that certain dietary factors may affect semen quality, and the mechanisms underlying the observed associations are likely multifactorial, involving complex interactions between diet, oxidative stress, inflammation, and hormone levels. Further research is required to confirm the results, fully elucidate the mechanisms underlying the associations, and identify specific dietary interventions that may improve male fertility outcomes.

Association between gastric cancer and the intake of different types of iron and meats

BACKGROUND

Heme and non-heme irons are two forms of iron in the diet. Few studies have evaluated the association between heme iron intake and the risk of gastric cancer (GC). We aimed to investigate the association between heme, non-heme and total iron intake and risk of GC in Iran.

METHODS

In a hospital-based case-control study, nutritionists interviewed 178 pathologically confirmed GC patients and 276 controls using a valid Diet History Questionnaire. Multiple logistic regression model was used to estimate Odds Ratios (OR) and 95% Confidence Intervals (CIs) for iron intake and risk of GC.

RESULTS

Subjects in the highest tertile of total iron intake were 46% less likely to get GC than those in the lowest (OR = 0.54, 95% CI: 0.32-0.92), however, the associations were not significant for intake of heme and non-heme iron. The risk of GC in the highest tertile of total meat intake was 2.51 times higher than the lowest. We found significant associations between GC and chicken (OR = 2.95; 95% CI: 1.66-5.22) and fish intake (OR = 1.89; 95% CI: 1.09-3.27), However, we found no associations between the risk of GC and intake of red meat, salted fish, and liver.

CONCLUSION

Total iron intake was associated with a lower risk of GC which could be partly due to the high prevalence of anemia in Iran. Although, we could not find any significant association between the risk of GC and the intake of heme and non-hem iron among the Iranian population.

Astaxanthin ameliorates inflammation, oxidative stress, and reproductive outcomes in endometriosis patients undergoing assisted reproduction: A randomized, triple-blind placebo-controlled clinical trial

Purpose

In a randomized, triple-blind, placebo-controlled clinical trial (RCT) including 50 infertile women with endometriosis candidate for assisted reproductive techniques (ART), we studied the effect of Astaxanthin (AST) on pro-inflammatory cytokines, oxidative stress (OS) markers, and early pregnancy outcomes.

Methods

Before and after 12 weeks of AST treatment (6 mg per day), blood serum and follicular fluid (FF) samples were collected from 50 infertile women with endometriosis stage III/IV undergoing ART. Pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) and OS markers (malondialdehyde [MDA], superoxide dismutase [SOD], catalase [CAT], and total antioxidant capacity [TAC]) were measured in the serum and FF. ART outcomes were also compared between the groups.

Results

Increased serum levels of TAC (398.661 ± 57.686 vs. 364.746 ± 51.569; P = 0.004) and SOD (13.458 ± 7.276 vs. 9.040 ± 5.155; P = 0.010) were observed after AST therapy in the treatment group. Furthermore, serum MDA (14.619 ± 2.505 vs. 15.939 ± 1.512; P = 0.031) decreased significantly following antioxidant treatment. In addition, significantly lower serum levels of IL-1β (4.515 ± 0.907 vs. 6.8760 ± 0.8478; P = 0.000), IL-6 (5.516 ± 0.646 vs. 5.0543 ± 0.709; P = 0.024) and TNF-α (2.520 ± 0.525 vs. 2.968 ± 0.548; P = 0.038) were observed after AST treatment. In addition, AST supplementation led to an improved number of oocytes retrieved (14.60 ± 7.79 vs. 9.84 ± 6.44; P = 0.043), number of mature (MII) oocytes (10.48 ± 6.665 vs. 6.72 ± 4.3; P = 0.041), and high-quality embryos (4.52 ± 2.41 vs. 2.72 ± 2.40; P = 0.024).

Conclusion

AST pretreatment can modulate inflammation and OS in endometriosis-induced infertile patients. ART outcomes also improved after 12 weeks of AST therapy. Our results suggest that AST can be a potential therapeutic target for infertile patients with endometriosis undergoing ART.

The effect of nutrition education for cancer prevention based on health belief model on nutrition knowledge, attitude, and practice of Iranian women

Background

In recent years, nutrition has received an increasingly important role in the etiology of cancer. Thus, public education about dietary factors associated with cancer risk or prevention could be an important intervention for cancer prevention, particularly in low- and middle-income countries where the burden of cancer is increasing rapidly and the access to care is limited. The age-standardized incidence of breast cancer was 35.8 among Iranian women in 2020. We aimed to study the effect of nutrition education on the knowledge, attitude, and practice of Iranian women towards dietary factors related to cancer.

Methods

In this interventional study, 229 women from public health centers were recruited and underwent three 75-min sessions of education based on the Health Belief Model (HBM). Participants were interviewed by trained interviewers using a validated and reproducible nutrition-related cancer prevention knowledge, attitude, and practice questionnaire (NUTCANKAP) questionnaire designed based on the HBM. Nutritional knowledge, attitude, and practice of participants were assessed through this questionnaire. Three 24-h dietary recalls (one weekend and two nonconsecutive weekdays) were also collected before and one month after the intervention.

Results

The mean age of the participants was 45.14 years, and the mean BMI was 27.2 kg/m². After the intervention, the participants had a higher intake of whole grain (p = 0.03) and a lower fat dairy (p = 0.009) and nuts (p = 0.04). However, the intake of high-fat dairy (p = 0.001) decreased after the intervention. We indicated significant differences in knowledge (p < 0.001) and nutritional practice scores (p = 0.01) after education. In addition, after the intervention, there were significant differences in the mean score of the HBM components, except for the perceived self-efficacy.

Conclusion

Participation in a nutrition education program positively impacted the knowledge and nutritional practices linked to cancer prevention.

Dual function of Selenium nanoparticles: Inhibition or induction of lysozyme amyloid aggregation and evaluation of their cell based cytotoxicity

Aberrant protein aggregation and the formation of amyloid deposits are associated with numerous neuro- and non-neurodegenerative disorders. Thus, one potential strategy is to eliminate these deposits by halting amyloid aggregation. Selenium nanoparticles (Se-NPs) have great potential in biomedicine for various therapeutic and diagnostic purposes and also have the ability to inhibit amyloid fibrillation. Herein, Hen Egg White Lysozyme (HEWL) was chosen as a protein model, and rod-like Se-NPs with diameters ranging from 90 to 120 nm were synthesized and the influence of shape and concentration of the particles on HEWL fibrillation was investigated. The effect of the nanoparticles on HEWL amyloid formation was analyzed using thioflavin T and Congo red binding assays, atomic force microscopy, and cytotoxicity assays. In the present study, it has been observed that these particles have a dual function in various concentrations. Using lower concentrations of Se-NPs ranging from 3-30 μg/ml, the Thioflavin T (ThT) fluorescence intensity decreased significantly by 60%, with an increased lag time compared to that of the control. While HEWL fibrillation substantially increased upon co-incubation with a higher concentration of these particles (300-2400μg/ml), and these results were verified by AFM, Congo red, and MTT assay. We showed that inhibitory or inductive influences of Se-NPs on the hen egg-white lysozyme (HEWL) amyloid aggregation are achieved via different independent mechanisms. These results demonstrate that dual-activity of Se-NPs might be a valuable targeting system for inhibiting amyloid aggregation, and thus, may play a useful role in new therapeutic and diagnostic strategies for amyloid-related disorders.

The Iranian Newborn Multiples Registry (IRNMR): a registry protocol

Purpose: Over the last decades, several twin/multiples registries have been developed worldwide, mostly concentrated in Europe and high-income countries (HICs). In Iran, we lack accurate nationwide epidemiological and biobank data on twins. We established the Iranian Newborn Multiples Registry (IRNMR) to evaluate the role of genetics and environmental factors in the variation of phenotypes among newborn monozygotic (MZ) and dizygotic (DZ) twin pairs. IRNMR is a multicenter hospital-based registry. Materials and methods: In the pilot phase, we collected epidemiological data from multiples born in Imam Khomeini Hospital complex and Aban Hospital located in Tehran, the capital of Iran, with a population exceeding 8 million, Allameh Bohlool Gonabadi Hospital, Gonabad, Razavi Khorasan, and Shahid Sadoughi Hospital, Yazd, Iran. Results: The IRNMR has recruited 457 sets of newborn twins and multiples so far. We hold follow-up sessions by mother and child health professionals to monitor multiples' growth, development, diseases, and mortality. Conclusions: We successfully developed a newborn multiples registry in Iran. This registry will create an invaluable database to study the relative influence of genes and environmental factors on various chronic diseases, growth, development, and behavioral disorders. We intend to collaborate with other centers to develop a large multicenter nationwide multiple birth registry and biobank in Iran.

Coulomb drag in metal monochalcogenides double-layer structures with Mexican-hat band dispersions

We theoretically study the Coulomb drag resistivity and plasmon modes behavior for a system composed of two parallelp-type doped GaS monolayers with Mexican-hat valence energy band using the Boltzmann transport theory formalism. We investigate the effect of temperature,T, carrier density,p, and layer separation,d, on the plasmon modes and drag resistivity within the energy-independent scattering time approximation. Our results show that the density dependence of plasmon modes can be approximated byp^0.5. Also, the calculations suggest ad^0.2and ad^0.1dependencies for the acoustic and optical plasmon energies, respectively. Interestingly, we obtain that the behavior of drag resistivity in the double-layer metal monochalcogenides swings between the behavior of a double-quantum well system with parabolic dispersion and that of a double-quantum wire structure with a large carrier density of states. In particular, the transresistivity value reduces exponentially with increasing the distance between layers. Furthermore, the drag resistivity changes asT²/p⁴(T^2.8/p^4.5) at low (intermediate) temperatures. Finally, we compare the drag resistivity as a function of temperature for GaS with other Mexican-hat materials including GaSe and InSe and find that it adopts higher values when the metal monochalcogenide has smaller Mexican-hat height.

The Effect of Astaxanthin and Metformin on Oxidative Stress in Granulosa Cells of BALB C Mouse Model of Polycystic Ovary Syndrome

Reactive oxygen species (ROS), involved in the pathogenesis of the polycystic ovary syndrome (PCOS), play a key role in the onset of apoptosis in follicles and granulosa cells (GCs). We aimed to investigate the antioxidant effects of AST and metformin separately and in combination on GCs using a PCOS mouse model. Forty-eight prepubertal female BALB C mice aged 25-30 days and weighing 12-14 g were studied. The PCOS model was created by subcutaneous injection of the dehydroepiandrosterone (DHEA) hormone in 8 mice of BALB C for 20 consecutive days. Apoptosis and the amount of ROS were evaluated in GCs of the ovaries via flow cytometry. The activity of AKT protein was measured by western blot, and the viability of GCs was investigated using spectrophotometry. Ovarian tissue sections were prepared, stained with H&E, and the morphology of the sections was examined. Statistical analysis was performed by SPSS v22.0 software using one-way ANOVA. We found that AST administration leads to a significant reduction in oxidative stress (P<0.01) and consequently a significant decrease in the rate of apoptosis (P<0.01). While the expression of AKT in the AST group revealed a significant increase (P<0.05), it decreased in the metformin group. However, it was still significantly higher than the control and PCOS groups. Ovulation was confirmed in both metformin and AST groups. Further studies are warranted to prove the efficacy of AST and to introduce it as a complementary therapeutic agent in PCOS.

Discriminatory Accuracy of the Gail Model for Breast Cancer Risk Assessment among Iranian Women

Background:

The Gail model is the most well-known tool for breast cancer risk assessment worldwide. Although it was validated in various Western populations, inconsistent results were reported from Asian populations. We used data from a large case-control study and evaluated the discriminatory accuracy of the Gail model for breast cancer risk assessment among the Iranian female population.

Methods:

We used data from 942 breast cancer patients and 975 healthy controls at the Cancer Institute of Iran, Tehran, Iran, in 2016. We refitted the Gail model to our case-control data (the IR-Gail model). We compared the discriminatory power of the IR-Gail with the original Gail model, using ROC curve analyses and estimation of the area under the ROC curve (AUC).

Results:

Except for the history of biopsies that showed an extremely high relative risk (OR=9.1), the observed ORs were similar to the estimates observed in Gail’s study. Incidence rates of breast cancer were extremely lower in Iran than in the USA, leading to a lower average absolute risk among the Iranian population (2.78, ±SD 2.45). The AUC was significantly improved after refitting the model, but it remained modest (0.636 vs. 0.627, ΔAUC = 0.009, bootstrapped P=0.008). We reported that the cut-point of 1.67 suggested in the Gail study did not discriminate between breast cancer patients and controls among the Iranian female population.

Conclusion:

Although the coefficients from the local study improved the discriminatory accuracy of the model, it remained modest. Cohort studies are warranted to evaluate the validity of the model for Iranian women.

Genetic risk score associations for myocardial infarction are comparable in persons with and without rheumatoid arthritis: the population-based HUNT study

Persons with rheumatoid arthritis (RA) have increased risk of myocardial infarction (MI). Overlapping associations with MI of weighted genetic risk scores (wGRS) for coronary artery disease (CAD) and RA is unknown in a population-based setting. Data from the prospective Nord-Trøndelag Health Study (HUNT2: 1995–1997 and HUNT3: 2006–2008) were used. wGRS added each participant’s carriage of all risk variants weighted by the coefficient from published association studies. Published wGRS for CAD and RA were analysed in Cox regression with MI as outcome, age as analysis time, and censoring at the first MI, death, or 31.12.2017. 2609 of 61,465 participants developed MI during follow-up (mean 17.7 years). The best-fitting wGRS for CAD and RA included 157 and 27 single-nucleotide polymorphisms, respectively. In multivariable analysis including traditional CAD risk factors, the CAD wGRS was associated with MI [hazard ratio = 1.23 (95% CI 1.18–1.27) for each SD increase, p < 0.0001] in RA patients (n = 433) and controls. The RA wGRS was not significant (p = 0.06). Independently from traditional risk factors, a CAD wGRS was significantly associated with the risk for MI in RA patients and controls, whereas an RA wGRS was not. The captured genetic risk for RA contributed little to the risk of MI.

Association of physical activity, body mass index and reproductive history with breast cancer by menopausal status in Iranian women

BACKGROUND

The incidence rate of breast cancer (BC) is increasing in low- and middle-income countries (LMICs), including Iran. We investigated the association between BC risk and physical activity (PA), body mass index (BMI), and reproductive history among Iranian women.

METHODS

We conducted a large hospital-based case-control study and compared 958 BC cases with 967 controls at the Cancer Institute of Iran during 2011-2016. We used multiple logistic regression models and adjusted for potential confounders to estimate odds ratios (ORs) and 95% confidence intervals (95%CIs) for the associations between BC and different risk factors, including low physical activity.

RESULTS

Women with high levels of physical activity had a lower risk of BC compared to those who were inactive (OR = 0.55, 95%CI: 0.41, 0.75). In premenopausal women, the association was observed only in normal-weight women (OR = 0.31, 95%CI: 0.13, 0.75), while it was limited to obese women in the postmenopausal group (OR = 0.29, 95%CI: 0.12, 0.66). We found a high risk of postmenopausal BC among overweight (OR = 1.69; 95%CI: 1.01, 2.81) and obese women (OR = 1.9; 95%CI: 1.14, 3.14) compared to women with a normal BMI. We observed an inverse association among postmenopausal women who had between three and five children (OR = 0.31, 95%CI 0.14, 0.64) and more than six children (OR = 0.21, 95%CI 0.12, 0.42) compared to nulliparous women.

CONCLUSIONS

Low levels of physical activity, low parity, and being overweight or obese were major risk factors for BC. For the first time, we report a strong association between physical activity and BC risk in Iranian women.

Effects in broiler hens of genetic lines differing in fertility, biotin supplementation, and age on relative abundance of oviductal transforming growth factor-β and carbonic anhydrase mRNA transcripts

There was evaluation of effects of biotin administration on oviductal abundance of transforming growth factor-β (TGF-β) and carbonic anhydrase (CA) mRNA transcript in younger and older broiler hens of relatively lesser and greater fertility lines. Additionally, effects of biotin supplementation on attenuation of age-related subfertility were evaluated. Hens from the relatively greater (Line D, n = 60) and lesser (Line B, n = 60) fertility rate line were randomly assigned to three treatment groups. Biotin was not or was administered in drinking water from 30 to 33 (younger age) and 53 to 56 (older age) wk of age to have access to no biotin (T₀), or 0.3 (T₁), or 0.45 (T₂) mg/L of biotin. There was assessment the relative oviductal abundances of TGF-β and CA mRNA transcript abundances. Supplemental biotin and age had no effect on the relative abundance of oviductal TGF-β mRNA transcript in hens of Line D. There, however, was a ten-fold greater abundance of TGF-β in hens of the T₀ group of Line B compared with Line D. Relative abundance of TGF-β mRNA transcript was greater in younger hens of Line B; however, biotin supplementation of older hens of the T₂ group of Line B resulted in a similar TGF-β abundance to that of younger hens. Inconstant with the TGF-β abundance, CA abundance in hens of Line B was not affected by supplemental biotin or bird age. Overall, differences in TGF-β or CA abundances did not affect fertility of broiler hens.

High prevalence of SCC mec-associated Phenol-soluble modulin gene in clinical isolates of methicillin-resistant. Staphylococcus aureus

INTRODUCTION

We aimed to determine the distribution of Phenol-soluble modulin-mec (psm-mec) gene and its relationship with biofilm formation in clinical methicillin-resistant S. aureus (MRSA).

METHODS

In a descriptive study, a total of 94 cefoxitin-resistant S. aureus isolates were collected from patients and tested for antibiotic susceptibility testing, multiplex polymerase chain reaction (MPCR) for detection of mecA and pvl genes, PCR for detection of psm-mec gene and SCCmec typing of psm-mec and pvl-positive isolates. Furthermore, isolates were tested by microtiter plate method for biofilm formation assay.

RESULTS

Multiplex PCR for detection of mecA and pvl genes was performed for all cefoxitin-resistant isolates. The mecA gene was found in 92 (97.9%) isolates but none of the isolates carried the pvl gene. Sixty-five (69.1%) isolates harbored psm-mec genes and 95.4% of these isolates belong to SCCmec type III. Statistical analysis showed a significant difference between the presence or absence of psm-mec gene and biofilm production (P<0.001).

CONCLUSION

In this study, more than half of the MRSA strains harbored psm-mec gene and almost one-fifth of them produced strong biofilm. Since the strains with strong biofilm formation have more antibiotic resistance and cause the long-lasting infection, for the suitable treatment of hospitalized patients with this kind of MRSA strains, we should be paid more attention to these strains.

Biofilm-producing ability of Staphylococcus spp isolated from different foodstuff products

BACKGROUND

In recent times, microbial-biofilm contamination has attracted considerable attention to the food industry. Pathogenic microorganisms can attach to food surfaces, grow on them, and form biofilm that cause an increase in the food safety risk. The mechanisms of biofilm formation have become an important issue in the food-processing industry, therefore, the aim of this study is to determine the biofilm formation and profiles of genes involved in biofilm production of staphylococci isolated from various foodstuff products.

MATERIAL AND METHODS

This cross-sectional study was conducted at some grocery stores and confectionaries from September 2015 to October 2016 in different areas of Isfahan, Iran. Staphylococcus spp were isolated from different foodstuff samples including sweet pastries, cakes and similar baked goods, dairy products such as cheese and yogurt, meat products such as sausages, and hamburgers. Standard microbiological methods were used for identification of Staphylococcus spp isolates. Antibiotic susceptibility pattern was determined by the disc diffusion method and icaA/icaD genes have been investigated as PCR target because of their role in the expression of intercellular adhesions involved in biofilm formation by S. aureus.

RESULTS

From a total of 194 different foodstuffs samples, 84 Staphylococcus spp were isolated. Out of the 84 Staphylococcus isolates, 95.2% (80/84) were positive to the ability of biofilm formation. Overall, 35.7% (30/84) and 26.2% (22/84) of Staphylococcus spp isolates were positive for icaA and icaD genes, respectively.

CONCLUSION

The results of the present study indicate that the remarkable rate of biofilm formation with the emergence of antibiotic resistance still remains a significant risk for the food safety, especially in foodstuff samples.

Comparison of methods to construct a genetic risk score for prediction of rheumatoid arthritis in the population-based Nord-Trøndelag Health Study, Norway

Objectives

To evaluate selection methods among published single-nucleotide polymorphisms (SNPs) associated with RA to construct predictive genetic risk scores (GRSs) in a population-based setting.

Methods

The Nord-Trøndelag Health (HUNT) Study is a prospective cohort study among the whole adult population of northern Trøndelag, Norway. Participants in HUNT2 (1995–1997) and HUNT3 (2006–2008) were included (489 RA cases, 61 584 controls). The initial SNP selection from relevant genome-wide studies included 269 SNPs from 30 studies. Following different selection criteria, SNPs were weighted by published odds ratios. The sum of each person’s carriage of all weighted susceptibility variants was calculated for each GRS.

Results

The best-fitting risk score included 27 SNPs [weighted genetic risk score 27 (wGRS27)] and was identified using P-value selection criterion ≤5 × 10−8, the largest possible SNP selection without high linkage disequilibrium (r2 &lt; 0.8), and lasso regression to select for positive coefficients. In a logistic regression model adjusted for gender, age and ever smoking, wGRS27 was associated with RA [odds ratio 1.86 (95% CI 1.71, 2.04) for each s.d. increase, P &lt; 0.001]. The AUC was 0.76 (95% CI 0.74, 0.78). The positive and negative predictive values were 1.6% and 99.7%, respectively, and the positive predictive value was not improved in sensitivity analyses subselecting participants to illustrate settings with increased RA prevalences. Other schemes selected more SNPs but resulted in GRSs with lower predictive ability.

Conclusion

Constructing a wGRS based on a smaller selection of informative SNPs improved predictive ability. Even with a relatively high AUC, the low PPV illustrates that there was a large overlap in risk variants among RA patients and controls, precluding clinical usefulness.

Overexpression of the Long Non-Coding RNA NeSt and FOXCUT in Early Stages of Prostate Cancer Samples as Promising Biomarkers

BACKGROUND

Prostate cancer is one of the most common cancers in males worldwide. Recently, it is well characterized that long non-coding RNAs (lncRNA) play critical roles in the initiation, development, and progression of prostate cancer. NeST, an intergenic lncRNA, was found to be a positive regulator of the pro-inflammatory cytokine, IFN-ɣ, which is responsible for both antitumor immunity properties as well as tumor evasion. FOXCUT, an-other lncRNA, is mainly a regulator of transcription factor, FOXC1 that is believed to be involved in tumor development and progression.

METHODS

In a case-control study, 66 paraffin-embedded prostate tissues representing 36 pathologically confirmed cancer and 30 control samples were examined. The cancer samples were classified in a total of three stages based on PSA levels, tumor volume, and Gleason score. RNA extraction was performed for quantitative determination of IFN-ɣ, lncRNA NeSt, and lncRNA FOXCUT gene expression in both case and control prostate tissues.

RESULTS

Our results showed that NeST lncRNA was significantly up-regulated in prostate cancer samples compared to control, while NeST lncRNA and IFN-ɣ gene expression was detected mainly in early stages of prostate cancer. The patients with higher NeST and FOXCUT expression had poor clinical features including PSA levels and tumor volume comparing those with lower expression. Moreover, there was a strong correlation between lncRNA FOXCUT and IFN-ɣ expression.

CONCLUSIONS

Our data suggests that lncRNA NeST and lncRNA FOXCUT may be able to be introduced as novel molecules involved in prostate cancer development and may provide a potential prognostic biomarker and therapeutic target.

Cross-talks between the kidneys and the central nervous system in multiple sclerosis

Multiple sclerosis (MS) is an inflammatory demyelinating disease, which is considered as a common autoimmune disorder in young adults. A growing number of evidences indicated that the impairment in non-neural tissues plays a significant role in pathology of MS disease. There are bidirectional relationship, metabolic activities and functional similarity between central nervous system (CNS) and kidneys which suggest that kidney tissue may exert remarkable effects on some aspects of MS disorder and CNS impairment in these patients compels the kidney to respond to central inflammation. Recently, it has been well documented that hormonal secretion possesses the important role on CNS abnormalities. In this regard, due to the functional similarity and significant hormonal and non-hormonal relationship between CNS and kidneys, we hypothesized that kidneys exert significant effect on initiation, progression or amelioration of MS disease which might be regarded as potential therapeutic approach in the treatment of MS patients in the future.

Primary ovarian insufficiency with t(5;13): a case report and literature review on disrupted genes

OBJECTIVES

To report a woman with primary ovarian insufficiency (POI) with reciprocal translocation between chromosomes 5 and 13.

METHODS

Chromosomal analysis (G-banding) of a 39-year-old woman with elevated gonadotropin levels and secondary amenorrhea and review of the literature with a special focus on disrupted genes at the reported breakpoints.

RESULTS

A reciprocal translocation between the long arms of chromosomes 5 and 13 was identified in the patient (46,XX,t(5;13)(q13;q14)). Investigation of the breakpoints revealed that the 13q14.1 region encompasses FOXO1 (forkhead box 1) gene, which has an important role in granulosa cell function and follicle maturation.

CONCLUSIONS

Autosomal translocations are rare in women with POI. We have reported the first case of a de novo reciprocal translocation involving chromosomes 5 and 13 in a POI patient. As one of the breakpoints encompasses the FOXO1 gene, it seems that disruption of this gene can be the cause of POI in this patient. This provides further evidence on the role of autosomal translocations in disrupting POI-associated genes. Therefore, concentrating on the genes at the breakpoints will be helpful to delineate the new biological pathways or genes involved in POI pathogenesis.

Comprehensive mutational analysis of primary and relapse acute promyelocytic leukemia

Acute promyelocytic leukemia (APL) is a subtype of myeloid leukemia characterized by differentiation block at the promyelocyte stage. Besides the presence of chromosomal rearrangement t(15;17), leading to the formation of PML-RARA (promyelocytic leukemia-retinoic acid receptor alpha) fusion, other genetic alterations have also been implicated in APL. Here, we performed comprehensive mutational analysis of primary and relapse APL to identify somatic alterations, which cooperate with PML-RARA in the pathogenesis of APL. We explored the mutational landscape using whole-exome (n=12) and subsequent targeted sequencing of 398 genes in 153 primary and 69 relapse APL. Both primary and relapse APL harbored an average of eight non-silent somatic mutations per exome. We observed recurrent alterations of FLT3, WT1, NRAS and KRAS in the newly diagnosed APL, whereas mutations in other genes commonly mutated in myeloid leukemia were rarely detected. The molecular signature of APL relapse was characterized by emergence of frequent mutations in PML and RARA genes. Our sequencing data also demonstrates incidence of loss-of-function mutations in previously unidentified genes, ARID1B and ARID1A, both of which encode for key components of the SWI/SNF complex. We show that knockdown of ARID1B in APL cell line, NB4, results in large-scale activation of gene expression and reduced in vitro differentiation potential.

The Effect of Formation of Titanium Nitride Thin Film on Surface Characteristics of Titanium by Nitrogen Ion Implantation

Titanium is used widely for applications that involve low weight and require suitable mechanical, biomedical and other desirable properties. In this paper, the effect of nitrogen ion implantation on surface structure and resistance against titanium corrosion and achievement of the best conditions for titanium nitride formation is investigated. For these experiments nitrogen ions with an energy of 30 keV and doses of 1 × 1018 to 5 × 1018 ion cm−2 were used. X-ray diffraction was performed for metallic analysis and investigation of new structures created by nitrogen ion implantation. Roughness variations before and after implantation were observed by atomic force microscopy. Corrosion analysis apparatus is used for comparison of resistance against titanium corrosion before and after ion implantation. Results show that nitrogen ion implantation has a substantial effect on resistance improvement against titanium corrosion. The surface morphology of the samples after corrosion testing is investigated using scanning electron microscopy. It is shown that the more important factor will control the final corrosion speed. In doses lower than 2×1018 ion cm−2, the roughness effect is most important, and in higher does, TiN phase formation is dominant.

MELATONIN ALLEVIATES BLEOMYCIN-INDUCED PULMONARY FIBROSIS IN MICE

Pulmonary fibrosis occurs as a common end-stage sequela of a number of acute and chronic lung diseases. Eicosanoids exert crucial roles in inflammatory processes pertinent to fibrogenesis induction, however, the role of cyclooxygenase 2 (COX-2) is not fully elucidated in most pulmonary fibrosis related-disorders. Recently, melatonin (MLN) has been introduced as an effective immuno-modulator and anti-oxidant agent. The present study aimed to investigate the effect of MLN on COX-2 expression in idiopathic pulmonary fibrosis (IPF). Animals were divided into five groups, including: 1) saline control, 2) 1% ethanol control, 3) MLN control, 4) bleomycin (BLM), in which mice were injected with BLM (15 mg/kg, i.p.) two times per week for four weeks, and 5) BLM+MLN, in which MLN was given to mice (10 mg/kg, i.p.) 30 minutes prior to BLM injections for four weeks. MLN administration significantly reduced body weight loss (P<0.05), the rate of mortality, edema formation, lung injury, COX-2 expression (P>0.05), interstitial tissue percentage volume (P<0.05), and also increased the alveolar space percentage volume. MLN attenuated the BLM-induced lung injury responses such as collagen accumulation and airway dysfunction in mice. Finally, histological evidence supported the ability of MLN to inhibit COX-2 expression. Thus, it may serve as a novel potential therapeutic agent for IPF.

Hyaluronic Acid: from biochemical characteristics to its clinical translation in assessment of liver fibrosis

CONTEXT

Hyaluronic acid (HA) is a high molecular weight polysaccharide that is distributed in all bodily tissues and fluids. The liver is the most important organ involved in the synthesis and degradation of HA. Research has shown that liver cell injury can affect serum HA levels. In this review, authors aimed to describe the biochemical and physiological roles of this glycosaminoglycan and its changes in various liver diseases.

EVIDENCE ACQUISITION

Liver fibrosis and in more severe form, cirrhosis are results of an imbalance between fibrogenesis and fibrinolysis. Liver biopsy is the gold standard to assess liver necro inflammatory injuries. This method is invasive and has some major side effects; therefore it is an unfavorable method for both physicians and patients. Now, a wide variety of noninvasive methods have been introduced based on evaluating serum level of different markers. They are safe, readily available, and more favorable. Serum HA levels are used by some researchers to assess stages of liver fibrosis.

RESULTS

There are several scientific studies indicating HA as a biomarker for high score fibrosis and cirrhosis in various liver diseases alone or in algorithm models. It seems from various algorithm models that the use of HA as a major constituent has more diagnostic reliability and accuracy than the use of HA alone.

CONCLUSIONS

Use of HA in an algorithm model, is an extra and valuable tool for assessing liver necro inflammatory injuries- in parallel with liver biopsy- but more comprehensive studies are needed to approve the use of HA as an appropriate clinical tool.

Sustained reduction of alloantibody secreting plasma cells and donor specific antibody with proteasome inhibition in mice

The long-lived plasma cells, which develop after alloantigen sensitization, produce donor specific alloantibodies (DSAs) that generate a positive serum cross-match and preclude transplantation. Bortezomib, a proteasome inhibitor, is being investigated in clinical desensitization protocols, however preclinical studies in a transplant model are nonexistent. We hypothesized that sustained treatment with only a proteasome inhibitor would eliminate plasma cells and reduce DSA over time. Cardiac allografts were transplanted into murine recipients. Eight weeks after allograft rejection the proteasome inhibitor, bortezomib, was injected intravenously twice weekly for 60 days. Serum alloantibody responses were assayed using flow cross-match. Total and alloreactive plasma cell numbers were enumerated using flow cytometry and ELISPOT. All recipients of cardiac allografts rejected their graft promptly within 16 days and demonstrated alloantibody by flow cross-match. DSA was sustained in the control mice while mice treated with bortezomib had sustained elimination of DSA and a marked reduction in plasma cell population. Also, bortezomib was associated with an increased level of BLyS. Within a murine model, proteasome inhibition can eliminate alloantibody secreting plasma cells, and reduce alloantibody. Cessation of bortezomib is not associated with return of DSA.

A comparative study on the effects of type I and type II diabetes on learning and memory deficit and hippocampal neuronal loss in rat

AIM

In addition to learning and memory impairments, diabetes may also brings about neuronal loss in different regions of the brain specially hippocampus. In this line, the present study was conducted to investigate the effects of type I (T1D) and type II (T2D) diabetes on cognitive function and hippocampal neuronal density in rat.

METHODS

Three groups of male Wistar rats (N.=6) were regarded as control, T1D and T2D. T1D was induced by 60 mg/kg body weight of STZ injection and T2D by 10% fructose treatment through drinking water. Two months after the induction of both types of diabetes, learning abilities and memory retention of animals were measured using Morris Water Maze and shuttle box. All animals were perfused afterwards and their brains processed for stereological examination of hippocampal neuronal density.

RESULTS

In parallel to significant decrease in learning and memory scores, T1D showed a meaningful reduction in hippocampal neuronal density, when compared to control group. In T2D, the reductions of cognitive scores as well as hippocampal neuronal density were not significant, when compared to control and T1D.

CONCLUSION

Although both types of diabetes led to neuronal loss and spatial learning and memory dysfunction, these abnormalities were more obvious in T1D, while they are probably age-related and duration-dependent in T2D.

The expression of p38, ERK1 and Bax proteins has increased during the treatment of newly diagnosed acute promyelocytic leukemia with arsenic trioxide

BACKGROUND

Promising reports exist regarding the use of arsenic trioxide (ATO) as first-line treatment in acute promyelocytic leukemia (APL). Although the in vitro effect of ATO is extensively studied, the in vivo mechanism(s) of ATO action is mostly unknown.

PATIENTS AND METHODS

Newly diagnosed APL patients were involved and received ATO (0.15 mg.kg/day) for 28 days as induction followed by consolidation therapy. Bone marrow (BM) aspirates were obtained on days 0, 14 and 28 of treatment for further molecular studies. Clinical findings and white blood cell counts were recorded as well.

RESULTS

Complete remission was observed in 17 (85%) patients with the median duration of 28 days (18-38) and cumulative dosage of median 280 mg (180-350). Hyperleukocytosis and APL differentiation syndrome (63%), gastrointestinal disorders (30%), liver enzyme elevation and night sweating (50%) were the most prevalent side-effects. The expression of Bax, ERK1 and p38 proteins and caspase-3 activity increased significantly in promyelocytes of BM aspirates at days 14 and 28 of induction therapy.

CONCLUSION(S)

These findings point toward the role of p38 and Bax in the induction of apoptosis, which was confirmed by increase in caspase-3 activity. However, the increase in ERK1 expression with regard to leukocytosis could translate to a proliferative/differentiation effect.

Antimicrobial susceptibility pattern of microorganisms involved in the pathogenesis of surgical site infection (SSI); A 1 year of surveillance

The aim of this study is to identify the antibiotic sensitivity pattern of pathogens involved in the process of surgical site infection, in surgical wards. Changes made in the pattern of antibiotic use will result in different microorganism susceptibility patterns, which needs correct determination for precise empiric antibiotic therapy. One thousand patients (62% men and 38% women, 18- 74-years-old, with mean age 43 +/- 8)) who underwent surgical treatment, in Alzahra University Hospital, Isfahan University of Medicine, Isfahan, Iran, were studied from 2005 to 2006. Surgical wound infections, based on the reported criteria, were aspirated for culturing within 1 plus gram staining of prepared smears. Minimum Inhibitory Concentrations (MICs) were determined for samples and all derived data were compared by SPSS 13 and WHO net 5 software. The prevalence of SSI was 13.3% with 150 positive cultures, totally. Of 150 bacteria, isolated from surgical site infections Staphylococcus aureus had most frequency (43%). Resistance of isolated organisms was 41.7% in amikacin, 65 and 78.6% in ceftazidime, 85.7% in ceftriaxone, 61.5% in ciprofloxacin, 78.8% in gentamicine, 6.4% in imipenem, 13% in meropenem and 70.6% in trimethoprim/sulfamethoxazole, respectively. 78.9% of Staphylococcus aureus isolates were MRSA and vancomycine was the most effective antibiotic without any resistance. Among 10 isolates of coagulase negative Staphylococcus, no vancomycine resistance was seen, but in contrast all cases were resistant to oxacillin. The most common gram negative organism was Klebsiella (18 isolates) in which 100 and 80% were sensitive to imipenem and meropenem, respectively. Seventeen cases were E. coli, in which the most sensitivity was to meropenem (80%) and imipenem (77.8%). Thirteen cases of Pseudomonas were detected, in which 16.7% were resistant to imipenem and 8.3% to meropenem. Our results demonstrated that the total antibiotic resistance is increasing among SSIs, with an up sloping pattern, which will contact with a constant empiric antibiotic therapy. So, precise up to date antibiogram tantalize us toward balancing the rate of total antibiotic resistance to SSIs.

First-line treatment of acute promyelocytic leukemia with arsenic trioxide without ATRA and chemotherapy

7073

Background: Standard treatment of APL is ATRA plus chemotherapy but Arsenic Trioxide (ATO) is most potent single agent against APL cells. Role of ATO in first line therapy of APL needs to clarify. Methods: Between may 2000 and September 2006,we treated 141 new cases of APL(Median age 28±12.8 y/o min=11,max=71) by 2 hours iv infusion of 0.15mg/kg ATO until complete remission. Trial approved by IRB and consent form obtained. Diagnosis was by clinical and morphologic characteristics and confirmed by cytogenetic and RT-PCR for detection of t(15,17) and presence of PML-RARa. After complete remission patients received consolidation by 28 days infusion of ATO for one or four courses.(one consolidation one month after CR and for some patients second, third and forth consolidations one month after first one and two another , one year and two year after CR) Results: : complete remission observed in 121 cases(85.8%) and early mortality rate was14.9%(most common cause of early mortality was APL syndrome,61.9%).Median follow up was 28 months. For patients who achieve to complete remission,one, two and three year disease free survival were 95.6%± 2%, 76.9±4% and 57± 6%,respectively. Many relapsed patients salvaged again with ATO alone so, two and three years overall survival for this cohort was 95.6%±2% and 83.7%±4%. Increasing number of consolidation from one to four couldn’t increase DFS or OS in one and two years after CR. Conclusions: ATO is effective in treatment of new cases of APL. Introduction of ATO in first line treatment of APL(with or without ATRA plus chemotherapy) needs a multi center randomized clinical trial.

No significant financial relationships to disclose.

Risk factors for early mortality, relapse and overall survival in new cases of APL treated by arsenic trioxide

7069

Background: There are several known risk factors for APL treatment by ATRA and chemotherapy, but risk factors for new cases of APL treated by Arsenic Trioxide are unknown. Methods: Between May 2000 and September 2006, we treated 141 new cases of APL (Median age 28±12.8 y/o min=11, max=71) by 2 hours iv infusion of 0.15mg/kg ATO until complete remission. Trial approved by IRB and consent form obtained. Diagnosis was by clinical and morphologic characteristics and confirmed by cytogenetic and RT-PCR for detection of t(15,17) and presence of PML-RARa. After complete remission patients received consolidation by 28 days infusion of ATO for one or four courses. Known risk factors for APL treatment outcome (including PML-RARa isoforms, presence of MRD during follow up and WBC count at presentation analyzed for early mortality, relapse rate, DFS and OS. Results: Complete remission observed in 121 cases (85.8%) and early mortality rate was 14.9%. short isoform of detected in 36% of patients and 18% presented by WBC more than 10,000/μl. For early mortality, APL differentiation syndrome during treatment and WBC count more than 10,000/μl were risk factors. (P<0.001 and p=0.011 respectively) For DFS only predicting factor for relapse was detection of MRD (by nested PCR or by real time PCR) during follow up (P=0.05). For prediction of OS, again only risk factor was detection of MRD(P<0.0001). Conclusions: Although WBC count before treatment and APL differentiation syndrome during treatment are risk factor for relapse, short isoform of APL is not a risk factor. After achieving to CR only risk factor is detection of MRD.

No significant financial relationships to disclose.

Real-time PCR analysis of PML-RARα in newly diagnosed acute promyelocytic leukaemia patients treated with arsenic trioxide as a front-line therapy

BACKGROUND

Recently, patients with acute promyelocytic leukaemia (APL) have experienced significant clinical gains after treatment with arsenic trioxide. However, the use of this agent as a front-line therapy for newly diagnosed patients is unclear.

PATIENTS AND METHODS

Of 95 newly diagnosed APL patients, 85 patients who achieved complete remission (CR) were sequentially evaluated during a 4-60 month period by conventional RT-PCR. A total of 30 patients (six relapsed and 24 in continued CR) were selected and monitored by quantitative real-time PCR (RQ-PCR) assay. The PML-RARalpha fusion transcripts values were normalised to every 10(6) copies of G6PDH transcripts (NQ).

RESULTS

RQ-PCR analyses showed a rapid rate of clearance of NQ levels during the courses of arsenic therapy. In the majority of patients in CR, the NQ levels were below 5 x 10(2) in peripheral blood (PB) samples. In all the relapsed cases with follow-up intervals of 1-6 months (median 3 months) clinical relapse was predictable by increasing NQ level above this threshold.

CONCLUSIONS

Our study highlights the usefulness of PB and the definition of threshold level for early prediction of relapse. The threshold level correlates well with risk of relapse; therefore, transcript ratio below the level should be regarded as a goal in the clinical management of this disease.

Quantitative analysis of PML-RARα in newly diagnosed acute promyelocytic leukemia patients treated with arsenic trioxide as a front-line therapy

6571

Background: Recently, patients with acute promyelocytic leukemia (APL) have experienced significant clinical gains after treatment with arsenic trioxide (As2O3). However, the potential role for use of this agent as a front-line therapy for newly diagnosed patients is unclear. Methods: From 95 patients with APL, 85 patients who achieved complete remission (CR) were sequentially evaluated during 4–60 months period of follow-up by conventional RT-PCR. A total of 30 patients (6 relapsed and 24 in continued long remission) were selected and monitored by quantitative real-time PCR (RQ-PCR) assay. Using ‘Hybridization Probes‘ technology, the expression of PML-RARα/G6PDH transcript ratio was analyzed in serial PB samples taken at different courses of disease and the results were compared with the clinical outcome. Results: More than 90% of patients obtained molecular remission, as determined by conventional RT-PCR in 1–3 months after start of arsenic therapy. RQ-PCR analyses showed a rapid rate of clearance of PML-RARα/G6PDH transcript level during the courses of arsenic therapy. In majority of the patients in CR the level of PML-RARα/ G6PDH ratio was always below 5×102 in PB samples. In all the relapsed cases with follow-up intervals of 1–6 months (median 3) clinical relapse was predictable by increasing transcript level above this threshold. Conclusions: Using a sensitive and quantitative method provided valuable information about effectiveness of arsenic as a front-line therapy in the management of newly diagnosed APL. Our study highlights the usefulness of PB and the definition of threshold level for early prediction of relapse. The threshold level correlates well with relapse risk; therefore, transcript ratio below the level should be regarded as a goal in the clinical management of this disease.

No significant financial relationships to disclose.

Treatment of acute promyelocytic leukemia with arsenic trioxide without ATRA and/or chemotherapy

INTRODUCTION

Arsenic trioxide is effective and approved for treatment of relapsed or refractory acute promyelocytic leukemia (APL) cases resistant to all-trans retinoic acid (ATRA), but its effect on new cases of APL is not clear.

MATERIALS AND METHODS

We studied 111 patients with APL. Arsenic trioxide was infused at 0.15 mg/kg daily dose, until complete remission was achieved. Then, after 28 days of rest, arsenic trioxide was infused daily for 28 days as consolidation therapy. We studied minimal residual disease (MRD) by semi-sensitive reverse transcription polymerase chain reaction (RT-PCR) on peripheral blood samples.

RESULTS

Complete remission was observed in 95 patients (85.6%). With the median (range) follow-up period of 16.5 (1-57) months, 1- and 2-year disease-free survival was 88.3% and 63.7%, respectively; 24 patients relapsed, 19 of whom achieved a second complete remission, again by arsenic trioxide. Third and fourth remissions were seen in some relapsed patients, again by arsenic trioxide. For patients in complete remission, 1- and 3-year survival was 95.5% and 87.6%, respectively. MRD was positive in four (8.3%) out of 48 cases during 1 year after remission induction; three of them relapsed clinically.

CONCLUSIONS

Arsenic trioxide is effective as first-line treatment for APL. Results of arsenic trioxide combination therapy with chemotherapy/ATRA requires further study.

Tracking alloreactive cell division in vivo

BACKGROUND

The study of alloimmune responses has been limited by a lack of assays that can track the behavior of alloreactive lymphocytes in vivo. Here we utilize an experimental system that allows the identification and study of alloreactive CD4+ lymphocytes responding to major histocompatibility antigens in vivo.

METHODS

Responder mouse lymphocytes were labeled with a fluorescein-based dye, adoptively transferred into irradiated allogeneic stimulator mice, and recovered at serial time points for analysis by flow cytometry.

RESULTS

Discrete generations of CD4+ responder lymphocytes proliferating specifically in response to allogeneic MHC class II were distinguished by fluorescein intensity. Successive division of alloreactive CD4+ lymphocytes was traced up to six generations after 60 hr.

CONCLUSIONS

This experimental system provides information on the division kinetics of alloreactive CD4+ cells. Other applications include immunophenotyping of alloreactive lymphocyte subsets. Further study of systems such as this will allow the detailed characterization of how alloimmune responses are initiated and proceed in vivo.

Cardiac allograft tolerance induced by intra-arterial infusion of recombinant adenoviral CTLA4Ig

BACKGROUND

Systemic administration of soluble recombinant fusion protein of cytotoxic T lymphocyte antigen 4 (CTLA4Ig) induces blockade of the CD28/B7 costimulatory pathway and promotes survival of allogeneic and xenogeneic grafts. We tested the efficacy of local expression of CTLA4Ig gene in the myocardium, induced by transduction with a recombinant adenovirus encoding the CTLA4Ig gene, on the survival of rat cardiac allografts.

METHODS

The donor hearts were perfused ex vivo with recombinant adenovirus encoding CTLA4Ig cDNA (AdCTLA4Ig) via intra-aorta coronary artery before transplantation. The distribution and duration of CTLA4Ig transgene expression in the myocardium was assessed by reverse transcriptase polymerase chain reaction (RT-PCR) or in situ RT-PCR after transplantation.

RESULTS

In situ RT-PCR demonstrated abundant expression of CTLA4Ig transgene in the endo-myocardium of AdCTLA4Ig-perfused cardiac grafts. Lewis and Brown Norway cardiac allografts transduced with AdCTLA4Ig survived indefinitely in nonimmunosuppressed Wistar Furth recipients. However, donor-strain skin grafts were rejected by long-term recipients of cardiac allografts, which also triggered the rejection of the primary heart grafts.

CONCLUSIONS

A single ex vivo intra-aortic infusion of recombinant adenovirus encoding the CTLA4Ig gene induced efficient transduction of the endo-myocardium and promoted the permanent survival of cardiac allografts in nonimmunosuppressed hosts. Despite the beneficial effect of local immunosuppression on cardiac allograft survival, the strategy failed to promote a state of donor-specific peripheral tolerance.

Cutting edge: alloimmune responses against major and minor histocompatibility antigens: distinct division kinetics and requirement for CD28 costimulation

Comparative study of alloimmune responses against major and minor histocompatibility Ags has been limited by the lack of suitable assays. Here, we use a bioassay that permits tracking of alloreactive CD4+ T cell populations as they proliferate in response to major or minor histocompatibility Ags in vivo. Division of alloreactive CD4+ T cells proceeded more rapidly in response to major histocompatibility Ags than minor Ags, although CD4+ T cells alloreactive to minor Ags had a similar capacity to divide successively up to eight times after stimulation. Allorecognition of minor histocompatibility Ags was highly dependent on CD28 costimulation, with the frequency of CD4+ T cells proliferating in response to minor Ags in the absence of CD28 costimulation reduced up to 20-fold. These findings highlight differences in signaling processes that lead to allorecognition of major and minor histocompatibility Ags and have implications on the design of interventions aimed at abrogating these responses.

Prevention of autoimmune recurrence and rejection by adenovirus-mediated CTLA4Ig gene transfer to the pancreatic graft in BB rat

Type 1 diabetes is the result of a selective destruction of pancreatic islets by autoreactive T-cells. Therefore, in the context of islet or pancreas transplantation, newly transplanted beta-cells are threatened by both recurrent autoimmune and alloimmune responses in recipients with type 1 diabetes. In the present study, using spontaneously diabetic BB rats, we demonstrate that whereas isolated islets are susceptible to autoimmune recurrence and rejection, pancreaticoduodenal grafts are resistant to these biological processes. This resistance is mediated by lymphohematopoietic cells transplanted with the graft, since inactivation of these passenger cells by irradiation uniformly rendered the pancreaticoduodenal grafts susceptible to recurrent autoimmunity. We further studied the impact of local immunomodulation on autoimmune recurrence and rejection by ex vivo adenovirus-mediated CTLA4Ig gene transfer to pancreaticoduodenal grafts. Syngeneic DR-BB pancreaticoduodenal grafts transduced with AdmCTLA4Ig were rescued from recurrent autoimmunity. In fully histoincompatible LEW-->BB transplants, in which rejection and recurrence should be able to act synergistically, AdmCTLA4Ig transduced LEW-pancreaticoduodenal allografts enjoyed markedly prolonged survival in diabetic BB recipients. In situ reverse transcription-polymerase chain reaction revealed that transferred CTLA4Ig gene was strongly expressed in both endocrine and exocrine tissues on day 3. These results indicate the potential utility of local CD28-B7 costimulatory blockade for prevention of alloimmune and autoimmune destruction of pancreatic grafts in type 1 diabetic hosts.