Characterization of physicochemical and immunogenic properties of allergenic proteins altered by food processing:a review

Food allergens are mainly naturally-occurring proteins with immunoglobulin E(IgE)-binding epitopes.Understanding the structural and immunogenic characteristics of allergenic proteins is essential in assessing whether and how food processing techniques reduce allergenicity.We here discuss the impacts of food processing technologies on the modification of physicochemical,structural,and immunogenic properties of allergenic proteins.Detection techniques for characterizing changes in these properties of food allergens are summarized.Food processing helps to reduce allergenicity by aggregating or denaturing proteins,which masks,modifies,or destroys antigenic epitopes,whereas,it cannot eliminate allergenicity completely,and sometimes even improves allergenicity by exposing new epitopes.Moreover,most food processing techniques have been tested on purified food allergens rather than food products due to potential interference of other food components.We provide guidance for further development of processing operations that can decrease the allergenicity of allergenic food proteins without negatively impacting the nutritional profile.

Preclinical Verification of Modulated Electro-Hyperthermia—Part III. Immunogenic Effects

The modulated electro-hyperthermia (mEHT) method is a unique approach that utilizes all the essential apoptotic pathways through an external radiofrequency (RF) signal. The high-frequency RF is amplitude-modulated and coupled capacitively to the target. The provided energy triggers the death receptors and FAS-FADD complexes in the malignant cells. Multi-pathway apoptosis produces immunogenic cell death (ICD). This ICD provides intracellular information about cancer cells by releasing damage-associated molecular patterns (DAMP), including membrane expression of calreticulin (CRT) and extracellular ATP, HMGB1, and HSP70, executing tumor-specific antigen presentation. The antigen-presenting cells (APCs) play a crucial role in reestablishing immune surveillance and hampering the tumor cells’ ability to hide, thereby evading immune attacks. The matured DCs (generally APCs) produce tumor-specific killer and helper T-cells, which have the potential to be active in distant metastases from the treated location. This unique mechanism of action underscores its potential in cancer treatment and extends the local mEHT treatment to the whole body anticancer therapy with an abscopal effect.

Immunogenic cell death-related long noncoding RNA influences immunotherapy against lung adenocarcinoma

Lung adenocarcinoma(LUAD)is the leading cause of cancer-related deaths,accounting for over a million deaths worldwide annually.Immunogenic cell death(ICD)elicits an adaptive immune response.However,the role of ICD-related long noncoding RNAs(lncRNAs)in LUAD is unknown.In this study,we investigated the characteristics of the tumor microenvironment in LUAD,the prognostic significance of ICD-related lncRNAs,and the half-maximal inhibitory concentration(IC50)of possible chemotherapeutic drugs.We sorted prognostic lncRNAs using univariate Cox regression and constructed a risk signature based on them.We then confirmed the model’s accuracy and generated a nomogram.Additionally,we performed immune microenvironment analysis,somatic mutation calculation,Tumor Immune Dysfunction and Exclusion(TIDE)analysis,and anticancer pharmaceutical IC50 prediction.Least absolute shrinkage and selection operator Cox regression identified 27 prognostic lncRNAs related to ICD,and a unique risk signature using 10 ICD-related lncRNAs was constructed.The risk score was confirmed to be a reliable predictor of survival,with the highest c-index score.The signature had a remarkable predictive performance with clinical applicability and could accurately predict the overall survival in LUAD.Furthermore,the lncRNA signature was closely associated with immunocyte invasion.We also analyzed the correlation between the risk score,tumor-infiltrating immune cells,and prognosis and identified high immune and ESTIMATE scores in low-risk patients.Moreover,we observed elevated checkpoint gene expression and low TIDE scores in high-risk patients,indicating a good immunotherapy response.Finally,high-risk patients were shown to be susceptible to anticancer medications.Therefore,our unique risk signature comprising 10 ICD-related lncRNAs was demonstrated to indicate the characteristics of the tumor-immune microenvironment in LUAD,predict patients’overall survival,and guide individualized treatment.

An Immunogenic Cell Death-Related Classification Predicts Prognosis and Response to Immunotherapy in Glioblastoma

To investigate the immunogenic Cell Death gene’s potential mechanism and prognostic value in glioblastoma. Information on GBM samples from The Cancer Genome Atlas database was downloaded, ICD genes were obtained, genotyping, integrated bioinformatics to verify the prognostic value of genotyping, and finally, prognostic model construction. Two subtypes associated with the ICD gene were obtained by consensus clustering, and the high ICD subtype (risk) group was associated with poor prognosis, high mutations in the PTEN gene, high stromal score, and high immune score. We also constructed a new classification system for GBM based on ICD characteristics. This study is the first to use immunogenic cell death genes for genotyping and successfully build a prognostic model.

Inducing immunogenic cell death in immuno-oncological therapies

Immunotherapy has revolutionized cancer treatment and substantially improved patient outcomes with respect to multiple types of tumors.However,most patients cannot benefit from such therapies,mainly due to the intrinsic low immunogenicity of cancer cells(CCs)that allows them to escape recognition by immune cells of the body.Immunogenic cell death(ICD),which is a form of regulated cell death,engages in a complex dialogue between dying CCs and immune cells in the tumor microenvironment(TME),ultimately evoking the damage-associated molecular pattern(DAMP)signals to activate tumor-specific immunity.The ICD inducers mediate the death of CCs and improve both antigenicity and adjuvanticity.At the same time,they reprogram TME with a“cold-warmhot”immune status,ultimately amplifying and sustaining dendritic cell-and T cell-dependent innate sensing as well as the antitumor immune responses.In this review,we discuss how to stimulate ICD based upon the biological properties of CCs that have evolved under diverse stress conditions.Additionally,we highlight how this dynamic interaction contributes to priming tumor immunogenicity,thereby boosting anticancer immune responses.We believe that a deep understanding of these ICD processes will provide a framework for evaluating its vital role in cancer immunotherapy.

Pre-clinical study of human umbilical cord mesenchymal stem cell transplantation for the treatment of traumatic brain injury: safety evaluation from immunogenic and oncogenic perspectives

Stem cell therapy is a promising strategy for the treatment of traumatic brain injury(TBI). However, animal experiments are needed to evaluate safety;in particular, to examine the immunogenicity and tumorigenicity of human umbilical cord mesenchymal stem cells(hu MSCs) before clinical application. In this study, hu MSCs were harvested from human amniotic membrane and umbilical cord vascular tissue. A rat model of TBI was established using the controlled cortical impact method. Starting from the third day after injury, the rats were injected with 10 μL of 5 × 10^(6)/m L hu MSCs by cerebral stereotaxis or with 500 μL of 1 × 10^(6)/m L hu MSCs via the tail vein for 3 successive days. hu MSC transplantation decreased the serum levels of proinflammatory cytokines in rats with TBI and increased the serum levels of anti-inflammatory cytokines, thereby exhibiting good immunoregulatory function. The transplanted hu MSCs were distributed in the liver, lung and brain injury sites. No abnormal proliferation or tumorigenesis was found in these organs up to 12 months after transplantation. The transplanted hu MSCs negligibly proliferated in vivo, and apoptosis was gradually observed at later stages. These findings suggest that hu MSC transplantation for the treatment of traumatic brain injury displays good safety. In addition, hu MSCs exhibit good immunoregulatory function, which can help prevent and reduce secondary brain injury caused by the rapid release of inflammatory factors after TBI. This study was approved by the Ethics Committee of Wuhan General Hospital of PLA(approval No. 20160054) on November 1, 2016.

Human IgG Fc promotes expression, secretion and immunogenicity of enterovirus 71 VP1 protein

Enterovirus （EV71） can cause severe neurological diseases, but the underlying pathogenesis remains unclear. The capsid protein, viral protein 1 （VP1）, plays a critical role in the pathogenicity of EVT1. High level expression and secretion ofVP 1 protein are necessary for structure, function and immunogenicity in its natural conformation. In our previous studies, 5 codon-optimized VP 1 DNA vaccines, including wt-VP 1, tPA-VP 1, VP l-d, VP 1-hFc and VP 1 - mFc, were constructed and analyzed. They expressed VP1 protein, but the levels of secretion and immunogenicity of these VP1 constructs were significantly different （P〈0.05）. In this study, we further investigated the protein lev- els of these constructs and determined that all of these constructs expressed VP1 protein. The secretion level was increased by including a tPA leader sequence, which was further increased by fusing human IgG Fc （hFc） to VP1. VP 1-hFc demonstrated the most potent immunogenicity in mice. Furthermore, hFc domain could be used to purify VPI-hFc protein for additional studies.

Immune response induced by hematoporphyrin derivatives mediated photodynamic therapy:Immunogenic cell death and elevated costimulatory molecules

Photodynamic therapy(PDT)not only destroys tumor cells directly but also induced anti-tumor immune response through damage-associated molecular patterns(DAMPs).It is reported that anti-tumor response was associated with light dose and photosensitizer used in PDT.In this study,4T1 tumor cells were implanted on both the right and left flanks of mice.Only the right tumor was treated by HpD-PDT,while the left tumor was not irradiated.The anti-tumor immune response induced by HpD-PDT was investigated.The expression of DAMPs and costimulatory molecules induced by HpD-PDT were tested by immuno fluorescence and flow cytometry in vivo.Different light doses of PDT were designed to treat 4T1 cells.The killing effect was assessed by CCK-8 kit and apoptosis kit.The expression of DAMPs on 4T1 cells after HpDPDT were evaluated by flow cytometry,western blot and ATP kit.This study showed that CD4^(+)T,CD8^(+)T and the production of IFN-γwere increased significantly on day 10 in righttumor after PDT treatment compared with control group.HpD-PDT enhanced the expression of calreticulin(CRT)on tumor tissue.Importantly,co-stimulatory molecular OX-40 and 4-1BB were elevated on CD8^(+)T cells.In vitro,immunogenic death of 4T1 cells was induced after PDT.Besides,the expression of DAMPs increased with the increasing of energy density.This study indicates that anti-tumor immune effect was induced by HpD-PDT.The knowledge of the involvement of CRT,ATP and co-stimulatory molecules uncovers important mechanistic insight into the anti-tumor immunogenicity.It was the first time that co-stimulatory molecules were investigated and found to elevate after PDT.

Gluten immunogenic peptide excretion detects dietary transgressions in treated celiac disease patients

BACKGROUND Life-long removal of gluten from the diet is currently the only way to manage celiac disease(CeD). Until now, no objective test has proven useful to objectively detect ingested gluten in clinical practice. Recently, tests that determine consumption of gluten by assessing excretion of gluten immunogenic peptides(GIP) in stool and urine have been developed. Their utility, in comparison with conventional dietary and analytical follow-up strategies, has not been fully established.AIM To assess the performance of enzyme-linked immunosorbent assay(ELISA) and point-of-care tests(PoCTs) for GIP excretion in CeD patients on gluten-free diet(GFD).METHODS We conducted an observational, prospective, cross-sectional study in patients following a GFD for at least two years. Using the Gastrointestinal Symptom Rating Scale questionnaire, patients were classified at enrollment as asymptomatic or symptomatic. Gluten consumption was assessed twice by 3-d dietary recall and GIP excretion(by ELISA in stool and PoCTs(commercial kits for stool and urine) in two consecutive samples. These samples and dietary reports were obtained 10 day apart one from the other. Patients were encouraged to follow their usual GFD during the study period.RESULTS Forty-four patients were enrolled, of which 19(43.2%) were symptomatic despite being on a GFD. Overall, 83 sets of stool and/or urine samples were collected.Eleven out of 44 patients(25.0%) had at least one positive GIP test. The occurrence of at least one positive test was 32% in asymptomatic patients compared with 15.8% in symptomatic patients. GIP was concordant with dietary reports in 65.9% of cases(Cohen′s kappa: 0.317). PoCT detected dietary indiscretions. Both ELISA and PoCT in stool were concordant(concomitantly positive or negative) in 67 out of 74(90.5%) samples. Excretion of GIP was detected in 7(8.4%) stool and/or urine samples from patients considered to be strictly compliant with the GFD by dietary reports.CONCLUSION GIP detects dietary transgressions in patients on long-term GFD, irrespective of the presence of symptoms. PoCT for GIP detection constitutes a simple homebased method for self-assessment of dietary indiscretions.

Immunogenicity and protective role of antigenic regions from five outer membrane proteins of Flavobacterium columnare in grass carp Ctenopharyngodon idella

Flavobacterium columnare causes columnaris disease in freshwater fi sh. In the present study, the antigenic regions of fi ve outer membrane proteins(OMPs), including zinc metalloprotease, prolyl oligopeptidase, thermolysin, collagenase and chondroitin AC lyase, were bioinformatically analyzed, fused together, and then expressed as a recombinant fusion protein in Escherichia coli. The expressed protein of 95.6 k Da, as estimated by 10% sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was consistent with the molecular weight deduced from the amino acid sequence. The purifi ed recombinant protein was used to vaccinate the grass carp, C tenopharyngodon idella. Following vaccination of the fi sh their Ig M antibody levels were examined, as was the expression of I g M, Ig D and Ig Z immunoglobulin genes and other genes such as MHC Iα and MHC I I β, which are also involved in adaptive immunity. Interleukin genes( IL), including I L- 1β, IL- 8 and I L- 10, and type I and type II interferon(I FN) genes were also examined. At 3 and 4 weeks post-vaccination(wpv), signifi cant increases in Ig M antibody levels were observed in the fi sh vaccinated with the recombinant fusion protein, and an increase in the expression levels of I g M, Ig D and Ig Z genes was also detected following the vaccinations, thus indicating that an adaptive immune response was induced by the vaccinations. Early increases in the expression levels of IL and IFN genes were also observed in the vaccinated fi sh. At four wpv, the fi sh were challenged with F. column a re, and the vaccinated fi sh showed a good level of protection against this pathogen, with 39% relative percent survival(RPS) compared with the control group. It can be concluded, therefore, that the fi ve OMPs, in the form of a recombinant fusion protein vaccine, induced an immune response in fi sh and protection against F. columnare.

Immunogenicity of recombinant attenuated Salmonella typhimurium expressing a 45-peptide hybrid antigen gene of Plasmodium falciparum

A synthetic hybrid 45-peptide gene of Plasmodium falciparum (Pf), which encoded two CSP repeated peptides NANP and three merozoite peptides SPf83. 1, SPf55. 1 and SPf35. 1, was cloned in an expression vector pWR450-1, then the recombinant plasmid pWRA was introduced into the attenuated Salmonella typhimurium SL3261. When used as a live vaccine and administered orally (po), intravenously (iv) or intraperitoneally (ip),the recombinant strain was able to live in vivo and elicit specific humoral and cellular immunity in BALB/c mice and rabbits. As oral immunization is safe and effective, it is thought that the live recombinant Salmonella tyPhimurium vaccine may bring the Pf oral live vaccine a step nearer.

Determination of gluten immunogenic peptides for the management of the treatment adherence of celiac disease: A systematic review

BACKGROUND Gluten is a complex mixture of proteins with immunogenic peptide sequences triggering the autoimmune activity in patients with celiac disease(CeD).Gluten immunogenic peptides(GIP)are resistant to gastrointestinal digestion and are then excreted via the stool and urine.Most common detection methods applied in the follow-up visits for CeD patients such as serology tests,dietetic interviews,questionnaires,and duodenal biopsy have been proved to be inefficient,invasive,or inaccurate for evaluating gluten-free diet(GFD)compliance.Determination of excreted GIP in stool and urine has been developed as a non-invasive,direct,and specific test for GFD monitoring.AIM To summarize published literature about the clinical utility of GIP determination in comparison to the tools employed for GFD monitoring.METHODS PubMed and Web of Science searches were performed using the keywords“gluten immunogenic peptides”or“gluten immunogenic peptide”and a combination of the previous terms with“feces”,“stools”,“urine”,“celiac disease”,“gluten-free diet”,and“adherence”to identify relevant clinical studies published in English and Spanish between 2012 to January 2021.Reference lists from the articles were reviewed to identify additional pertinent articles.Published articles and abstracts reporting the clinical use of GIP determination in stool and/or urine for the follow-up of patients with CeD in comparison with other tools in use were included.Case reports,commentaries,reviews,conference papers,letters,and publications that did not focus on the aims of this review were excluded.RESULTS Total of 15 publications were found that involved the use of GIP determination in stool and/or urine to monitor the adherence to the GFD in comparison to other tools.Studies included both children and adults diagnosed with CeD and healthy volunteers.Overall,these preliminary studies indicated that this novel technique was highly sensitive for the detection of GFD transgressions and therefore could facilitate the follow-up of patients with CeD.Tools identified in this work included the CeD-specific serology,dietetic questionnaires,symptomatology,and the duodenal biopsy.Review of the literature revealed that the rates of GFD adherence may vary between 30%-93%using either stool or urine GIP determination,49%-96%by the serology,59%-94%using the dietetic questionnaires,56%-95%by the reported symptoms and 44%-76%with the duodenal biopsy.In addition,the association between the different methods and histological abnormalities(Marsh II-III)was found to be 33%-100%for GIP determination(stool and urine),25%-39%for CeD-specific serology,3%-50%for dietetic questionnaires,and 22%-28%for the symptomatology.CONCLUSION Excreted GIP detection is the precise approach for determining voluntary or involuntary gluten consumption in CeD patients preventing future complications arising from gluten exposure.

Generation and Immunogenicity of a Recombinant Adenovirus Co-Expressing the E2 Protein of Classical Swine Fever Virus and the GP5 Protein of Porcine Reproduction and Respiratory Syndrome Virus

Classical swine fever （CSF） and porcine reproduction and respiratory syndrome （PRRS） are both economically important, highly contagious diseases of swine worldwide. To develop an effective vaccine to control these two diseases, we constructed a recombinant adenovirus rAdV-GP52AE2, using a replication-defective human adenovirus serotype 5 as a delivery vector, to co-express the GP5 protein of highly pathogenic porcine reproduction and respiratory syndrome virus （PRRSV） and the E2 protein of classical swine fever virus （CSFV）. Foot-and-mouth disease virus （FMDV） 2A peptide was used as a linker between the GP5 and E2 proteins to allow automatic self-cleavage of the polyprotein. The GP5 and E2 genes were expressed as demonstrated by immunofluorescence assay and Western blotting. Immunization of mice resulted in a CSFV-neutralizing antibody titer of 1：128 and a PRRSV-neutralizing antibody titer of 1：16. The lymphoproliferative responses were detected by Cell Counting Kit-8 assay and the stimulation index of CFSV-specific and PRRSV-specific lymphocytes in the rAdV-GP52AE2 group was significantly higher than that in the negative control group. The results show that rAdV-GP52AE2 can induce both effective humoral and cell-mediated immune responses in mice. The protective efficacy of the recombinant virus against CSF was evaluated in immunized rabbits, which were protected from fever induced by challenge with C-strain. Our study provides supporting evidence for the use of FMDV 2A to develop a bivalent genetically-engineered vaccine.

Immunogenicity of Lyophilized MVA Vaccine for HIV-1 in Mice Model

Highly attenuated modified vaccinia Ankara（MVA） is sensitive to repeat freeze-thaw cycle and easy to lose activity. In order to make the activity of MVA vaccine remain stable during its manufacturing, storage, and administration, the lyophilization as a good option could be resorted to; through screening, the right stabilizer composition and its production procedure were obtained. The final moisture content of freezing-dried recombinant MVA-HIV vaccine was lower than 3%. It can be reconstituted quickly and shows regular physical appearance and stable potency. In vivo functional experiment, mice were divided randomly into the liquid vaccination group, the lyophilized vaccination group, and the control group. Having been DNA vaccine priming, the mice were boosted with a dose of 10^7 pfu MVA- HIV vaccine, which produced indistinguishable antibody titer and cytotoxic T-lymphocyte（CTL） level compared with those of liquid vaccination group （ P 〉 0.05 ）. These results demonstrate that lyophilized MVA vaccine can induce high immunogenicity in mice.

Investigation of bone reconstruction using an attenuated immunogenicity xenogenic composite scaffold fabricated by 3D printing

Bone is known to have a natural function to heal itself.However,if the bone damage is beyond a critical degree,intervention such as bone grafting may be imperative.In this work,the fabrication of a novel bone scaffold composed of natural bone components and polycaprolactone(PCL)using 3D printing is put forward.α1,3-galactosyltransferase deficient pigs were used as the donor source of a xenograft.Decellularized porcine bone(DCB)with attenuated immunogenicity was used as the natural component of the scaffold with the aim to promote bone regeneration.The 3D printed DCB-PCL scaffolds combined essential advantages such as uniformity of the interconnected macropores and high porosity and enhanced compressive strength.The biological properties of the DCB-PCL scaffolds were evaluated by studying cell adhesion,viability,alkaline phosphatase activity and osteogenic gene expression of human bone marrow-derived mesenchymal stem cells.The in vitro results demonstrated that the DCB-PCL scaffolds exhibit an enhanced performance in promoting bone differentiation,which is correlated to the DCB content.Furthermore,critical-sized cranial rat defects were used to assess the effect of DCB-PCL scaffolds on bone regeneration in vivo.The results confirm that in comparison with PCL scaffolds,the DCB-PCL scaffolds can significantly improve new bone formation in cranial defects.Thus,the proposed 3D printed DCB-PCL scaffolds emerge as a promising regeneration alternative in the clinical treatment of large bone defects.

Comparative Study on the Immunogenicity between Hsp70 DNA Vaccine and Hsp65 DNA Vaccine in Human Mycobacterium Tuberculosis

The BALB/c mice were immunized with Hsp70 DNA and Hsp65 DNA vaccines in human Mycobacterium tuberculosis. Eight weeks after immunization, the eyeballs were removed, blood and spleen taken, and intraperitoneal macrophages were harvested. The lymphocytic stimulating index (SI) was used to measure the cellular proliferating ability and NO release to measure the phagocytic activity of the macrophages. With ELISA kit, the levels of interleukin-2 (IL-2) and interferon-γ (IFN-γ) in serum and the splenic lymphocytic cultured supernatant were detected. The results showed that after the mice were immunized with 100 μg/mouse of Hsp70 DNA vaccine intramuscularly, the splenic lymphocytic proliferating ability in the mice was significantly increased as compared with that in the control group, vector group and Hsp65 DNA vaccine group (P<0.01); The contents of NO in the intraperitoneal macrophages of the mice were significantly lower than in the control group and Hsp65 DNA vaccine group (P<0.01); The levels of serum IL-2 in the mice were significantly higher than in the control group, but there was no statistical difference between Hsp65 DNA group and vector group (P>0.05); The contents of serum IFN-γ in the mice were significantly higher than in the control group, but significantly lower than in the Hsp65 DNA vaccine group (P<0.05). It was indicated that immunization with Hsp70 DNA vaccine could obviously enhance the immune response, but its intensity seemed inferior to Hsp65 DNA vaccine. The anti-infection mechanisms and clinical use in the future of the vaccines of Hsp70 DNA and Hsp65 DNA are worth further studying.

Prokaryotic Expression and Immunogenicity of Major Antigen Epitope of Rabbit Haemorrhagic Disease Virus VP60

[ Objective] To investigate the immunogenicity of main antigen epitope of RHDV （ Rabbit haemorrhagic disease virus） VP60 expressed in a prokaryotic system. [ Method] The major antigen epitope gene of RHDV VP60 was amplified by RT-PCR. It was cloned into pET-28b （ ＋ ） and expressed in E. coli Rosetta strain. The recombinant protein was detected by Western blot. The pudfied recombinant protein was used to immunize rabbits in order to observe its immunogenicity. [ Result] Western blot analysis revealed a clear band at approximately 24.0 kDa. The purified recom- binant protein reacted with the purified RHDV in ELISA. [ Conclusion] The prokaryotically expressed main antigen epitope of RHDV VP60 shows good immunogenicity.

Preparation and immunogenicity of tag-free recombinant human eppin

Human epididymal protease inhibitor （eppin） may be effective as a male contraceptive vaccine. In a number of studies, eppin with an engineered His6-tag has been produced using prokaryotic expression systems. For production of pharmaceutical-grade proteins for human use, however, the His6-tag must be removed. This study describes a method for producing recombinant human eppin without a His6-tag. We constructed plasmid pET28a （＋）-His6-tobacco etch virus （TEV）-eppin for expression in Escherichia coli. After purification and refolding, the fusion protein His6-TEV-eppin was digested with TEV protease to remove the His6-tag and was further purified by NTA-Ni2＋ affinity chromatography. Using this procedure, 2 mg of eppin without a His6-tag was isolated from 1 I of culture with a purity of 〉95%. The immunogenicity of the eppin was characterized using male Balb/c mice.

Efficacy,effectiveness,immunogenicity- are not the same in vaccinology

Manuscript of Carrera et al is devoted to immunization in inflammatory bowel disease(IBD)that is very important issue in gastroenterology.However,some specific definitions used in the article need clarification.Efficacy of vaccine is measured in a randomised,placebo-controlled studies,that are expensive and difficult to plan.Moreover,it is unethical to offer a placebo instead of vaccine.For all of these reasons,efficacy of vaccine is measured in IBD patients rarely.Effectiveness of vaccine is measured as an epidemiological affect from observational studies.These studies are also uncommon in IBD because it would be difficult to perform a study that assess the prevalence of one rare disease(vaccine-preventable)in patients with a chronic rare condition,such as IBD.Immunogenicity of vaccine refers to the ability of a vaccine to induce an immune response in a vaccinated individual that is,in fact,the matter of the article.

Investigation of immunogenicity of cryopreserved limbal stem cells

AIM: To investigate changes in immunogenicity of cryopreserved limbal stem cells. METHODS: Cryopreserved limbal stem cells, fresh primary limbal stem cells and blank controls were inoculated subcutaneously in C57BL-6 mice and the percentage of CD25 cells in limbal explants was determined by flow cytometry at day 21 post inoculation. Morphological studies were performed by light and electron microscopy of limbal explant sections. RESULTS: The number of regional and systemic lymphocytes derived from cryopreserved limbal stem cells was lower than that from fresh primary limbal stem cells. CONCLUSION: Lymphocytes derived from cryopreserved limbal stem cells showed changes in immunogenicity, but the significance is unknown. The cryopreservation and thawing methods await further study.