Structure of HLA molecules and immunosuppressive effects of HLA derived peptides

Impact of tumor size on the outcomes of hepatic resection for hepatocellular carcinoma: a retrospective study

BACKGROUND

To evaluate the impact of tumor size on the perioperative and long-term outcomes of liver resection for hepatocellular carcinoma (HCC).

METHODS

We reviewed the patients' data who underwent liver resection for HCC between November 2009 and 2019. Patients were divided into 3 groups according to the tumor size. Group I: HCC < 5 cm, Group II: HCC between 5 to 10 cm, and Group III: HCC ≥ 10 cm in size.

RESULTS

Three hundred fifteen patients were included in the current study. Lower platelets count was noted Groups I and II. Higher serum alpha-feto protein was noted in Group III. Higher incidence of multiple tumors, macroscopic portal vein invasion, nearby organ invasion and presence of porta-hepatis lymph nodes were found in Group III. More major liver resections were performed in Group III. Longer operation time, more blood loss and more transfusion requirements were found in Group III. Longer hospital stay and more postoperative morbidities were noted in Group III, especially posthepatectomy liver failure, and respiratory complications. The median follow-up duration was 17 months (7-110 months). Mortality occurred in 100 patients (31.7%) and recurrence occurred in 147 patients (46.7%). There were no significant differences between the groups regarding recurrence free survival (Log Rank, p = 0.089) but not for overall survival (Log Rank, p = 0.001).

CONCLUSION

HCC size is not a contraindication for liver resection. With proper selection, safe techniques and standardized care, adequate outcomes could be achieved.

HLA Class II Polymorphism and Humoral Immunity Induced by the SARS-CoV-2 mRNA-1273 Vaccine

The vaccines designed against the SARS-CoV-2 coronavirus are based on the spike (S) protein. Processing of the S protein by antigen-presenting cells (APC) and its subsequent presentation to T cells is an essential part of the development of a humoral response. HLA-class II alleles are considered immune response genes because their codified molecules, expressed on the surface of APCs (macrophages, dendritic, and B cells) present antigenic peptides to T cell via their T cell receptor (TCR). The HLA-class II genes are highly polymorphic, regulating what specific peptides induce follicular helper T cells (TFH) and promote B lymphocyte differentiation into plasma or memory B cells. This work hypothesizes that the presence of certain HLA-class II alleles could be associated with the intensity of the humoral response (amount, length) to the SARS-CoV2 mRNA 1273 vaccine. We have studied the relationship between the HLA-class II typing of 87 health workers and the level of antibodies produced 30 days after vaccination. We show a possible association between the HLA-DRB1* 07:01 allele and the HLA-DRB1*07:01~DQA1*02:01~DQB1*02:02 haplotype to a higher production of antibodies 30 days after the administration of the second dose of mRNA-1273.

Effects of Red Blood Cell Transfusions on Distant Metastases of Oral Squamous Cell Carcinomas

Simple Summary

Patients with distant metastasis of oral squamous cell carcinoma should be identified at an early stage of disease. In this study, we investigated if patients who received red blood cell transfusions are at risk for the development of distant metastasis. A positive correlation was found between RBC transfusion (HR = 2.42) and the occurrence of M+ in a multivariate regression model. Therefore, the administration of RBC can be considered as an independent prognostic factor and special attention should be paid to its detrimental effects in the perioperative management of OSCC patients.

Abstract

There is no consensus on the effect of red blood cell (RBC) transfusions on patients with oral squamous cell carcinoma (OSCC). The aim of this study was to investigate the association between RBC administration and the occurrence of distant metastases (M+) after surgical treatment of OSCC. All medical records of patients who underwent primary surgery for OSCC in our department (2003–2019) were analyzed retrospectively (n = 609). Chi and Cox regression models were used to analyze the influence of transfusion on the development of M+, and survival rates. Kaplan–Meier curves were used for graphical presentation. A multitude of patient-specific factors showed a statistical impact in univariate analysis (transfusion, age, gender, diabetes, pT, pN, L, V, Pn, G, UICC, adjuvant therapy, free microvascular transplant, preoperative hemoglobin level). Transfusion status and pN stage were the only variables that showed a significant correlation to M+ in the multivariate Cox model. The hazard ratios for the occurrence of M+ were 2.42 for RBC transfusions and 2.99 for pN+. Administration of RBC transfusions was identified as a significant prognostic parameter for the occurrence of distant metastases after surgical treatment of OSCC. Hence, the administration of RBC transfusions should be considered carefully in the perioperative management.

Open MHC Class I Conformers: A Look through the Looking Glass

Studies carried out during the last few decades have consistently shown that cell surface MHC class I (MHC-I) molecules are endowed with functions unrelated with antigen presentation. These include cis–trans-interactions with inhibitory and activating KIR and LILR, and cis-interactions with receptors for hormones, growth factors, cytokines, and neurotransmitters. The mounting body of evidence indicates that these non-immunological MHC-I functions impact clinical and biomedical settings, including autoimmune responses, tumor escape, transplantation, and neuronal development. Notably, most of these functions appear to rely on the presence in hematopoietic and non-hematopoietic cells of heavy chains not associated with β2m and the peptide at the plasma membrane; these are known as open MHC-I conformers. Nowadays, open conformers are viewed as functional cis-trans structures capable of establishing physical associations with themselves, with other surface receptors, and being shed into the extracellular milieu. We review past and recent developments, strengthening the view that open conformers are multifunctional structures capable of fine-tuning cell signaling, growth, differentiation, and cell communication.

Do Red Blood Cell Transfusions Influence Long-Term Outcomes in Patients Undergoing Primary Surgery for Oral Squamous Cell Carcinoma?

PURPOSE

There is no consensus on the impact of red blood cell (RBC) transfusion on patients with oral squamous cell carcinoma (OSCC). The purpose of this study was to investigate the association between RBC transfusions and overall survival (OS) and tumor-free survival (TFS) after operative treatment of OSCC.

METHODS

In this retrospective cohort study, all patients treated with primary surgery between 2003 and 2017 because of OSCC were chart reviewed. The occurrence and amount of RBC transfusions (0; 1-3; >3 units) was correlated with OS and TFS by Kaplan-Meier survival and Cox regression analyses. Demographic, clinical, and pathological parameters were also evaluated in order to identify confounding factors.

RESULTS

Of 420 patients (243 [57.9%] male) with a mean age of 62.6 years, 67 (16.0%) received RBC transfusion. There were statistically significant (P < .01) differences in 5-year OS respectively TFS in transfused patients for the Kaplan-Meier survival analysis (0 units = 70.6%; [95% confidence interval {CI}: 65.0-75.4%] respectively 63.2% [95% CI: 57.4-68.4%], 1-3 units = 47.2% [95% CI: 29.4-63.1%] respectively 40.6% [95% CI: 24.6-55.95%] and >3 units = 48.9% [95% CI: 20.9-72.1%] respectively 30.5% [95% CI: 8.9-55.8%]). After multivariate adjustments for demographic, clinical, and pathological parameters, RBC transfusion could not be sustained as a significant prognostic factor in OS respectively TFS (1-3 units: hazard ratio = 1.5 [95% CI: 0.7-3.2] respectively 1.3 [95% CI: 0.7-2.6]; >3 units: hazard ratio = 1.2 [95% CI: 0.5 - 3.0] respectively 1.1 [95% CI: 0.5-2.4]).

CONCLUSIONS

Although RBC transfusion was not identified as a significant prognostic parameter in multivariate analysis, a clear trend for shorter OS and TFS for transfused patients in univariate and Kaplan-Meier survival analysis could be shown.

Implications of perioperative allogeneic red blood cell transfusion on the immune-inflammatory response

Background

The allogeneic transfusion-related immunomodulation (TRIM) may be responsible for an increase in survival of renal transplants but in contrast it could increase the rate of bacterial infections or the recurrence rate of tumors post-operatively.

Objective

This review focuses in the implications of perioperative allogeneic transfusions on the immune-inflammatory response of surgical transfused patients.

Results

ABTs modify immune functions in recipients including decrease of the number of lymphocytes; decrease the CD4 cells; decrease the CD4/CD8 T-cell ratio; decrease NK cells; and decrease the lymphocyte response to mitogens. TRIM effects may be mediated by allogeneic white cells present in blood products; soluble peptides present in transfused plasma; and/or biologic mediators released into the supernatant of blood units. A recent systematic review and meta-analysis including 36 clinical observational studies (n = 174,036) concluded that perioperative ABTs not only decreased overall survival and reduced colorectal cancer-specific survival. Furthermore ABTs increased the rate of infectious, cardiac, pulmonary and anastomotic complications in colorectal cancer patients undergoing surgery.

Conclusions

It has been demonstrated by laboratory tests that TRIM is associated with transfusion recipient immune alterations but its influence in colorectal cancer recurrence after resection remains controversial though may exist. Surgical techniques reducing intraoperative blood loss have limited the number of ABTs perioperatively, however increase in mortality continues to be reported in literature after ABT in colorectal cancer surgery. Poor survival associated to TRIM in colorectal cancer might be due to higher number of allogeneic transfused units and/or prolonged length of blood storage.

HLA-A promoter, coding, and 3'UTR sequences in a Brazilian cohort, and their evolutionary aspects

HLA-A is the second most polymorphic locus of the human leucocyte antigen (HLA) complex encoding a key molecule for antigen presentation and NK cell modulation. Many studies have evaluated HLA-A variability in worldwide populations, focusing mainly on exons, but the regulatory segments have been poorly characterized. HLA-A variability is particularly high in the segment encoding the peptide-binding groove (exons 2 and 3), which is related to the antigen presentation function and the balancing selection in these segments. Here we evaluate the genetic diversity of the HLA-A gene considering a continuous segment encompassing the extended promoter (1.5 kb upstream of the first translated ATG), all exons and introns, and the entire 3' untranslated region, by using massively parallel sequencing. To achieve this goal, we used a freely available bioinformatics workflow that optimizes read mapping for HLA genes and defines complete sequences using either the phase among variable sites directly observed in sequencing data and probabilistic models. The HLA-A variability detected in a highly admixed population sample from Brazil shows that the HLA-A regulatory segments present few, but divergent sequences. The regulatory segments are in close association with the coding alleles. Both exons and introns are highly variable. Moreover, patterns of molecular diversity suggest that the promoter, in addition to the coding region, might be under the same selective pressure, but a different scenario arises when it comes to exon 4 and the 3'UTR segment.

Predictors of recurrence in hepatitis C virus related hepatocellular carcinoma after hepatic resection: a retrospective cohort study

OBJECTIVE

Egypt is one of the hot spots in the international map of Hepatocellular carcinoma (HCC), which is where hepatitis C virus (HCV) infection is the major risk factor in development of HCC (80%). Due to low organ donation rates and lack of deceased liver transplantation, hepatic resection is the main line of treatment for HCC patients with sufficient liver reserve. We introduce our experience with patients who had HCV related HCC who underwent hepatic re-section to determine various predictors of tumour recurrence in this group. This is the first study to come from a country where chronic HCV hepatitis is endemic.

MATERIALS AND METHODS

This is a retrospective cohort study of 208 cases of HCC in hepatitis C virus positive patients with cirrhotic livers who underwent first-time liver resection, in Gastroenterology Surgical Centre, Mansoura University, Egypt during the period from January 2002 to December 2011. Shapiro-Wilk test was used to assess normality of data. Predictors of HCC recurrence were assessed by bivariate correlation tests, univariate analysis using the chi-square and t-test and binary logistic regression analysis. A P value <0.05 was considered statistically significant.

RESULTS

Tumour recurrence occurred in 88 patients (42.3%). Most of the recurrences occurred within the first year 55 patients (62.5%). The most common site for recurrence was the liver (n=68, 77.3%). Based on the univariate analysis; significant variables predicting tumor recurrence were alpha feto-protein (AFP), blood transfusion, multi-focality, cut margin, microvascular invasion, lack of capsule, tumour grade and stage. Based on multivariate analysis, the main variables predicting tumor recurrence were blood transfusion, cut margin, tumour capsule and microvascular invasion.

CONCLUSION

Although the predictors of recurrence are the same for both HBV and HCV related HCC, the rate and aggressiveness of recurrence are higher in HCV related HCC.

Contemporary perioperative care strategies

Background

Historically, the preoperative and postoperative care of patients with gastrointestinal cancer was provided by surgeons. Contemporary perioperative care is a truly multidisciplinary endeavour with implications for cancer-specific outcomes.

Methods

A literature review was performed querying PubMed and the Cochrane Library for articles published between 1966 to 2012 on specific perioperative interventions with the potential to improve the outcomes of surgical oncology patients. Keywords used were: fast-track, enhanced recovery, accelerated rehabilitation, multimodal and perioperative care. Specific interventions included normothermia, hyperoxygenation, surgical-site infection, skin preparation, transfusion, non-steroidal anti-inflammatory drugs, thromboembolism and antibiotic prophylaxis, laparoscopy, radiotherapy, perioperative steroids and monoclonal antibodies. Included articles had to be randomized controlled trials, prospective or nationwide series, or systematic reviews/meta-analyses, published in English, French or German.

Results

Important elements of modern perioperative care that improve recovery of patients and outcomes in surgical oncology include accelerated recovery pathways, thromboembolism and antibiotic prophylaxis, hyperoxygenation, maintenance of normothermia, avoidance of blood transfusion and cautious use of non-steroidal anti-inflammatory drugs, promotion of laparoscopic surgery, chlorhexidine–alcohol skin preparation and multidisciplinary meetings to determine multimodal therapy.

Conclusion

Multidisciplinary management of perioperative patient care has improved outcomes.

Negative impact of blood transfusion on recurrence and prognosis of hepatocellular carcinoma after hepatic resection

BACKGROUND

In perioperative management of hepatic resection for hepatocellular carcinoma, excessive blood loss and blood transfusion greatly influence postoperative complications and prognosis of the patients. We evaluated the influence of blood products use on postoperative recurrence and prognosis of patients with hepatocellular carcinoma.

METHODS

The subjects were 66 patients who underwent elective hepatic resection for hepatocellular carcinoma without concomitant microwave or radiofrequency ablation therapy nor other malignancies between January 2001 and June 2006. We retrospectively investigated the influence of the use of blood products including red cell concentration and fresh frozen plasma on recurrence of hepatocellular carcinoma and overall survival.

RESULTS

In multivariate analysis, the dose of blood products transfusion was a significant predictor of disease-free and overall survival. Both disease-free and overall survival rates of those who were given blood products were significantly worse than those who did not receive. On the other hand, in univariate analysis of disease-free and overall survival after hepatic resection and clinical variables, the amount of blood loss was not a significant predictor of recurrence or death.

CONCLUSION

Transfusion of blood products is associated with increased recurrence rate and worse survival after elective hepatic resection for patients with hepatocellular carcinoma.

Assessment of blood-products use as predictor of pulmonary complications and surgical-site infection after hepatectomy for hepatocellular carcinoma

BACKGROUND

In perioperative management after hepatectomy, some patients require fresh frozen plasma (FFP) to treat coagulopathy associated with blood loss. However, several studies have suggested a correlation between blood products and pulmonary complications or surgical-site infection (SSI).

METHODS

The subjects were 99 patients who underwent hepatectomy for hepatocellular carcinoma without plasma exchange for postoperative liver failure in the Department of Surgery, Jikei University Hospital, between January 2000 and December 2006. We investigated the association of 16 factors including age; gender; preoperative ICG(R15); type of resection; concomitant resection of other digestive organs; duration of operation; blood loss; hepatitis virus status; postoperative minimum platelet count, maximum serum total bilirubin (max T-Bil), minimum serum albumin, or minimum prothrombin time; and the dose of red-blood-cell concentration (RC), FFP, platelet concentration, or albumin given in relation to postoperative pulmonary complications and SSI.

RESULTS

In univariate analysis, pulmonary complications were correlated with gender (P = 0.012), max T-Bil (P = 0.043), dose of RC given (P = 0.007), dose of FFP given (P < 0.001), and dose of albumin given (P < 0.001). In multivariate analysis, pulmonary complications were correlated with FFP given (P = 0.031) and albumin given (P = 0.020), while the incidence of SSI was not correlated with any factors.

CONCLUSION

Excessive FFP and albumin administration may cause pulmonary complications after hepatectomy.

Pneumonia as a complication of blood product transfusion in the critically ill: Transfusion-related immunomodulation (TRIM)

BACKGROUND

An increased risk of postoperative infection (including pneumonia) attributable to the receipt of allogeneic blood transfusion has been investigated as a possible manifestation of transfusion-related immunomodulation (TRIM) in 16 randomized controlled trials (RCTs) and approximately 40 observational studies.

OBJECTIVES

This review categorizes RCTs and observational studies with regard to the inference that they permit about possible mediators of TRIM-allogeneic white cells (WBCs), WBC-derived soluble mediators, and/or allogeneic plasma-and examines whether the totality of the clinical evidence supports an association between allogeneic blood transfusion and postoperative infection.

RESULTS

When all available studies are considered together in meta-analyses, three types of studies show no increased risk of postoperative infection in association with allogeneic blood transfusion: a) RCTs comparing recipients of buffy-coat-reduced and prestorage-filtered, WBC-reduced allogeneic red cells; b) RCTs comparing recipients of allogeneic and autologous blood; and c) observational studies comparing patients transfused before and after implementation of WBC reduction. RCTs comparing recipients of nonbuffy-coat-reduced and WBC-reduced red blood cells may point to a TRIM effect, but they cannot yet be subjected to formal meta-analysis.

CONCLUSIONS

No overwhelming clinical evidence has been presented to establish the existence of a TRIM effect that relates allogeneic blood transfusion to postoperative infection.

Quantitative structure-activity relationships and the prediction of MHC supermotifs

The underlying assumption in quantitative structure-activity relationship (QSAR) methodology is that related chemical structures exhibit related biological activities. We review here two QSAR methods in terms of their applicability for human MHC supermotif definition. Supermotifs are motifs that characterise binding to more than one allele. Supermotif definition is the initial in silico step of epitope-based vaccine design. The first QSAR method we review here--the additive method--is based on the assumption that the binding affinity of a peptide depends on contributions from both amino acids and the interactions between them. The second method is a 3D-QSAR method: comparative molecular similarity indices analysis (CoMSIA). Both methods were applied to 771 peptides binding to 9 HLA alleles. Five of the alleles (A*0201, A*0202, A*0203, A*0206 and A*6802) belong to the HLA-A2 superfamily and the other four (A*0301, A*1101, A*3101 and A*6801) to the HLA-A3 superfamily. For each superfamily, supermotifs defined by the two QSAR methods agree closely and are supported by many experimental data.

Anemia, allogenic blood transfusion, and immunomodulation in the critically ill

Anemia and allogenic RBC transfusions are exceedingly common among critically ill patients. Multiple pathologic mechanisms contribute to the genesis of anemia in these patients. Emerging risks associated with allogenic RBC transfusions including the transmission of newer infectious agents and immune modulation predisposing the patient to infections requires reevaluation of current transfusion strategies. Recent data have suggested that a restrictive transfusion practice is associated with reduced morbidity and mortality during critical illness, with the possible exception of acute coronary syndromes. In this article, we review the immune-modulatory role of allogenic RBC transfusions in critically ill patients.

A comparative molecular similarity indices (CoMSIA) study of peptide binding to the HLA-A3 superfamily

Epitope identification is the basis of modern vaccine design. The present paper studied the supermotif of the HLA-A3 superfamily, using comparative molecular similarity indices analysis (CoMSIA). Four alleles with high phenotype frequencies were used: A*1101, A*0301, A*3101 and A*6801. Five physicochemical properties-steric bulk, electrostatic potential, local hydrophobicity, hydrogen-bond donor and acceptor abilities-were considered and 'all fields' models were produced for each of the alleles. The models have a moderate level of predictivity and there is a good correlation between the data. A revised HLA-A3 supermotif was defined based on the comparison of favoured and disfavoured properties for each position of the MHC bound peptide. The present study demonstrated that CoMSIA is an effective tool for studying peptide-MHC interactions.

Exposure to allogeneic plasma and risk of postoperative pneumonia and/or wound infection in coronary artery bypass graft surgery

BACKGROUND

A relationship may exist between the immunomodulatory effects of allogeneic blood transfusion and the volume of transfused allogeneic plasma and/or the number of transfused plasma-containing units.

STUDY DESIGN AND METHODS

The records of 416 consecutive patients undergoing coronary artery bypass graft operations at the Massachusetts General Hospital were reviewed. Exposure to allogeneic plasma in units of transfused RBCs, platelets, FFP, and cryoprecipitate was recorded, and diagnoses of postoperative pneumonia and wound infection were made by CDC criteria. The association between postoperative infection and exposure to allogeneic plasma was calculated by logistic regression analyses adjusting for the effects of confounding factors that related to severity of illness, difficulty of operation, and risk of postoperative pneumonia.

RESULTS

Two hundred seventy-four patients received (mean +/- SE) 636.2 +/- 64.3 mL of allogeneic plasma, contained in 8.5 +/- 0.7 units of blood components. Sixty-four patients (15.4%) developed pneumonia and/or wound infection, and 54 (13.0%) developed pneumonia. Patients who did (n = 64) or did not develop infection received 956.6 +/- 180.6 and 321.3 +/- 39.6 mL of plasma, respectively (p<0.0001). In multivariate analyses, the volume of transfused allogeneic plasma was not associated with postoperative pneumonia and/or wound infection (p = 0.24), pneumonia (p = 0.21), or wound infection (p = 0.74). Similarly, the number of transfused plasma-containing units was not associated with these outcomes (p = 0.08, p = 0.08, and p = 0.46, respectively).

CONCLUSION

A relationship between the exposure to allogeneic plasma and the risk of postoperative pneumonia and/or wound infection was not detected in this study population.