The allele frequency net database ( http://www.allelefrequencies.net ) is an online repository that contains information on the frequencies of immune genes and their corresponding alleles in different populations. The extensive variability observed in genes and alleles related to the immune system response and its significance in transplantation, disease association studies and diversity in populations led to the development of this electronic resource. At present, the system contains data from 1133 populations in 608 813 individuals on the frequency of genes from different polymorphic regions such as human leukocyte antigens, killer-cell immunoglobulin-like receptors, major histocompatibility complex Class I chain-related genes and a number of cytokine gene polymorphisms. The project was designed to create a central source for the storage of frequency data and provide individuals with a set of bioinformatics tools to analyze the occurrence of these variants in worldwide populations. The resource has been used in a wide variety of contexts, including clinical applications (histocompatibility, immunology, epidemiology and pharmacogenetics) and population genetics. Demographic information, frequency data and searching tools can be freely accessed through the website.

The BCR-ABL oncogene is central in the pathogenesis of chronic myeloid leukemia (CML). Here, tandem nanospray mass spectrometry was used to demonstrate cell surface HLA-associated expression of the BCR-ABL peptide KQSSKALQR on class I-negative CML cells transfected with HLA-A*0301, and on primary CML cells from HLA-A3–positive patients. These patients mounted a cytotoxic T-lymphocyte response to KQSSKALQR that also killed autologous CML cells, and tetramer staining demonstrated the presence of circulating KQSSKALQR-specific T cells. The findings are the first demonstration that CML cells express HLA-associated leukemia-specific immunogenic peptides and provide a sound basis for immunization studies against BCR-ABL.

Objective To assess the safety and efficacy of the B lymphocyte (anti-CD20) antibody, rituximab, in the treatment of steroid-resistant moderately active ulcerative colitis (UC). Methods A double-blinded, randomised controlled trial with a 2:1 ratio of treatment:placebo (phase II) was carried out in the setting of a University teaching hospital. The subjects comprised 24 patients with moderately active UC who have either failed to respond to conventional corticosteroid therapy or who have relapsed during corticosteroid withdrawal. Five of 8 placebo-treated patients and 12 of 16 rituximab-treated patients were receiving azathioprine, 6-mercaptopurine or methotrexate. Two infusions of rituximab 1 g in 500 ml of 0.9% saline intravenously over 4 h (n=16) or saline placebo (n=8) were given at 0 and 2 weeks. Patients still receiving corticosteroids on entry (placebo group 7/8; rituximab group 14/16) continued a standard steroid tapering regimen. The primary end point was remission (Mayo score ≤2) at 4 weeks. Secondary end points included response (Mayo score reduced ≥3) at 4 and 12 weeks. Results Mayo score at entry was higher in rituximab-treated patients (mean 9.19; 95% CI 8.31 to 10.06) than for placebo patients (7.63; 6.63 to 8.62, p=0.03). At week 4 only 1/8 placebo-treated patients and 3/16 rituximab-treated patients were in remission (p=1.0), but 8/16 rituximab-treated patients had responded compared with 2/8 placebo-treated patients, with a median reduction in Mayo score of 2.5 (rituximab) compared with 0 (placebo; p=0.07). This response was only maintained to week 12 in 4/16. Mucosal healing was seen at week 4 in 5/16 rituximab-treated patients and 2/8 placebo-teated patients (non-significant). Rituximab was well tolerated, with one chest infection, three mild infusion reactions plus one case of (probably unrelated) non-fatal pulmonary embolism. Conclusions Rituximab has no significant effect on inducing remission in moderately active UC not responding to oral steroids. There was a possible short-term response that was not sustained. Rituximab is well tolerated in UC. Clinical trial number NCT00261118.

BACKGROUND: Lung injury manifest clinically as adult respiratory distress syndrome (ARDS) is a common cause of morbidity and mortality following acute pancreatitis (AP). Neutrophils play a critical role in the progression of AP to ARDS. C-x-C chemokines are potent neutrophil chemoattractants and activators and have been implicated in AP. AIMS: To evaluate the effect of blocking the C-x-C chemokine, cytokine induced neutrophil chemoattractant (CINC), in AP on pancreatic inflammation and the associated lung injury in rats. METHODS: AP was induced by hourly intraperitoneal injections of caerulein. Goat anti-CINC antibody was administered either before or after starting caerulein injections to evaluate the prophylactic and therapeutic effects, respectively. Severity of AP was determined by measuring plasma amylase, pancreatic water content, and pancreatic myeloperoxidase (MPO) activity as a measure of neutrophil sequestration in the pancreas. Lung injury was determined by measurement of pulmonary microvascular permeability and lung MPO activity. RESULTS: Treatment with anti-CINC antibody had little effect on caerulein induced pancreatic damage. However, it reduced the caerulein mediated increase in lung MPO activity as well as lung microvascular permeability when administered either prophylactically (lung MPO (fold increase over control): 1.53 (0.21) v 3.30 (0.46), p<0.05; microvascular permeability (L/P%): 0.42 (0.07) v 0.77 (0.11), p<0.05) or therapeutically (lung MPO (fold increase over control): 2.13 (0.10) v 4.42 (0.65), p<0.05; microvascular permeability (L/P%): 0.31 (0.05) v 0.79 (0.13), p<0.05). CONCLUSION: Treatment with anti-CINC antibody afforded significant protection against pancreatitis associated lung injury. These results suggest that CINC plays an important role in the systemic inflammatory response in AP.

Mesenchymal stem cells (MSCs) modulate immune responses and maintain self-tolerance. Their trophic activities and regenerative properties make them potential immunosuppressants for treating autoimmune and autoinflammatory diseases. MSCs are drawn to sites of injury and inflammation where they can both reduce inflammation and contribute to tissue regeneration. An increased understanding of the role of MSCs in the development and progression of autoimmune disorders has revealed that MSCs are passive targets in the inflammatory process, becoming impaired by it and exhibiting loss of immunomodulatory activity. MSCs have been considered as potential novel cell therapies for severe autoimmune and autoinflammatory diseases, which at present have only disease modifying rather than curative treatment options. MSCs are emerging as potential therapies for severe autoimmune and autoinflammatory diseases. Clinical application of MSCs in rare cases of severe disease in which other existing treatment modalities have failed, have demonstrated potential use in treating multiple diseases, including rheumatoid arthritis, systemic lupus erythematosus, myocardial infarction, liver cirrhosis, spinal cord injury, multiple sclerosis, and COVID-19 pneumonia. This review explores the biological mechanisms behind the role of MSCs in autoimmune and autoinflammatory diseases. It also covers their immunomodulatory capabilities, potential therapeutic applications, and the challenges and risks associated with MSC therapy.