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PubMed2003

Multicenter Canadian study of prehospital trauma care.

OBJECTIVE: To evaluate whether the type of on-site care a trauma patient receives affects outcome. SUMMARY BACKGROUND DATA: The controversy regarding the prehospital care of trauma patients between Advanced Life Support (ALS) and Basic Life Support (BLS) is ongoing. Due to this unresolved controversy, as well as historical, cultural, and political factors, there are significant variations with respect to the type of prehospital care available for trauma patients. METHODS: This prospective cohort study compared three types of prehospital trauma care systems: Montreal, where physicians provide ALS (MD-ALS); Toronto, where paramedics provide ALS (PMD-ALS); and Quebec City, where emergency medical technicians provide BLS only (EMT-BLS). The study took advantage of this variation to evaluate the association between the type of on-site care and mortality in patients with major life-threatening injuries. All patients were treated at highly specialized tertiary (level I) trauma hospitals. The main outcome measure was death as a result of injury. Follow-up was to hospital discharge. RESULTS: The overall mortality rates by type of on-site personnel were physicians 35%, paramedics 24%, and EMTs 18%. For patients with major but survivable trauma, the overall mortality rates were physicians 32%, paramedics 28%, and EMTs 26%. The overall mortality rate of patients receiving only BLS at the scene was 18% compared to 29% for patients receiving ALS. For the subgroup of patients with major but survivable injuries, the mortality rates were 30% for ALS and 26% for BLS. The adjusted increased risk for mortality in patients receiving ALS at the scene was 21%. CONCLUSIONS: In urban centers with highly specialized level I trauma centers, there is no benefit in having on-site ALS for the prehospital management of trauma patients.

Adult↗
PubMed1995

Out-of-hospital provider use of epinephrine for allergic reactions: pilot program.

OBJECTIVE: To describe experience with an out-of-hospital provider program for the recognition and field management of allergic reactions by advanced life support (ALS) and basic life support (BLS) providers. METHODS: Data sheets completed between June 1, 1988, and August 31, 1993, and records from receiving sites (physicians' offices or EDs) were reviewed for information regarding the presentation of the allergic reaction, the time course and treatment provided out of hospital, and the clinical outcome at the receiving health care facility. RESULTS: Thirty-seven data sheets were completed during the study period. Fourteen (38%) of the providers were BLS providers. The epinephrine was supplied from the emergency medical services (EMS) provider's personal kit in 35% of the cases, from an EMS vehicle in 57% of the cases, and by the patient in 8% of the cases. Availability of the kits allowed administration of epinephrine prior to the arrival of the first EMS vehicle in 41% of the instances and prior to physician on-line medical command in 65% of all the instances (predominantly by BLS providers). Overall, 77% of the patients experienced alleviation of their symptoms of respiratory difficulty, swelling, or rash after epinephrine administration, while 20% were unchanged and 3% worsened. All patients receiving epinephrine had an ED diagnosis of allergic reaction, and no adverse event was encountered on follow-up of the patients treated. CONCLUSIONS: Severe allergic reactions can be reliably identified and safely managed by out-of-hospital providers, including BLS providers. Providing personal anaphylactic treatment kits and increasing the pool of providers trained to manage allergic reactions (including BLS providers) can often decrease the time to treatment.

Adrenergic Agonists↗
PubMed1998

Advanced life support vs basic life support field care: an outcome study.

OBJECTIVE: To determine whether the provision of advanced life support (ALS) field care has any impact on patient outcome in the urban Canadian environment. METHODS: A convenience cohort study was conducted of all emergent ambulance transfers of adults to an urban Canadian hospital from May 22 to July 31, 1996. Data were collected from ambulance call reports regarding presenting complaint and field interventions applied, and from hospital records regarding time in the ED, hospital length of stay (LOS), and discharge disposition. Patient outcomes were compared within 7 presenting complaint groups (chest pain, altered level of consciousness, shortness of breath, abdominal pain, motor vehicle crash, falls, and other) by field care level: level 1--BLS (basic life support) vs levels 2 and 3--ALS. RESULTS: The study population consisted of 1,397 patients. No significant differences were seen between BLS and ALS patients on baseline demographics. ED triage score did not depend on field care level for any group, implying that those in the ALS group were not inherently sicker. Outcome measures (ED LOS, admission rates, and hospital LOS) showed no significant differences between BLS and ALS for each presenting complaint group. Discharge dispositions were analyzed by chi2 but were not varied enough to allow reliable analysis. Observation of trends suggested no difference between BLS and ALS. CONCLUSIONS: There was no beneficial impact on the measured patient outcomes found in association with the provision of ALS vs BLS field care in Metropolitan Toronto for patients who were brought to a nontrauma center.

Adult↗
PubMed1994

The experimental production of big liver and spleen disease in broiler breeder hens.

Big liver and spleen disease (BLS) was reproduced experimentally by intravenous (IV) and oral (PO) administration of BLS inocula to susceptible broiler breeder hens 34 to 36 weeks of age. Serological and pathological signs of BLS similar to those seen in the natural disease occurred in inoculated and in-contact birds. Splenomegaly was the earliest and often the only necropsy finding, with hepatomegaly and kidney enlargement occurring in some birds later in the course of the disease. After IV administration, serum antigen was detected between 2 and 4 weeks, and antibody between 3 and 5 weeks. After PO administration, antigen was detected between 2 and 4 weeks, and antibody between 3 and 6 weeks. Antibody persisted in all birds to the end of the experiment (6 weeks), and horizontal transmission probably occurred since in-contact birds developed BLS. Liver probably contained the highest concentration of BLS agent because it had the highest infectivity.

Animals↗
PubMed1981

Coliform inhibition by bacteriocin-like substances in drinking water distribution systems.

Bacterial isolates from an unchlorinated potable groundwater system and a chlorinated surface water system were screened by an agar overlay method for the ability to produce bacteriocin-like substances (BLS) inhibitory to the growth of Escherichia coli, Klebsiella sp., and Enterobacter aerogenes. The production of coliform-specific BLS by noncoliform bacteria varied with the site and date of isolation as well as the genus of the producer strain. A total of 448 bacterial isolates were screened from the chlorinated system, and 22.1% produced BLS specific for at least one of the three coliforms. In the unchlorinated system, 7.9% (n = 696) possessed this ability. Flavobacterium/Moraxella comprised 57.1% of all bacteria (from both systems) producing BLS. The possibility that BLS interfere with coliform detection in standard bacteriological water quality tests is discussed.

Bacteria↗
PubMed2002

Diagnostic usefulness of antibodies against ribosome recycling factor from Brucella melitensis in human or canine brucellosis.

The diagnostic usefulness of an enzyme-linked immunosorbent assay (ELISA) using a purified recombinant ribosome recycling factor from Brucella melitensis (CP24 antigen) was tested in human and canine infections caused by smooth and rough Brucella species, respectively. Anti-CP24 antibodies were detected in 9 (43%) of 21 consecutive cases of canine brucellosis and in 8 (53%) of 15 dogs followed for 60 days after the diagnosis of acute brucellosis. Among eight patients with acute brucellosis, anti-CP24 antibodies were detected in four in the 10 weeks following diagnosis, but the remaining four were negative during the whole follow-up (22 weeks). The frequency of anti-CP24 antibodies was also low among 24 patients with subacute brucellosis and 23 patients with chronic illness (29 and 26%, respectively). While all patients positive for anti-CP24 antibodies were also positive for antibodies to total cytoplasmic proteins of Brucella (CP), five were negative for antibodies to another cytoplasmic protein, the Brucella lumazine synthase (BLS). When a larger sample of 35 human sera negative for anti-BLS antibodies was assayed, 85.7% were positive for anti-CP24 antibodies, suggesting that the combined measurement of both reactivities could yield a higher sensitivity than any test alone. To test this hypothesis, an ELISA combining both antigens was designed. The percentage of positive results among chronic cases was higher for this assay than for the individual measurement of anti-CP24 or anti-BLS antibodies (83 versus 26 and 65%, respectively) and was closer to the value obtained for anti-CP antibodies (91%). The frequency of anti-CP24 antibodies is low in both canine and human brucellosis. In the latter case, however, an ELISA combining CP24 and BLS is more sensitive than assays measuring anti-CP24 or anti-BLS antibodies separately and almost as sensitive as the ELISA using CP.

Animals↗
PubMed1994

Functional complementation of major histocompatibility complex class II regulatory mutants by the purified X-box-binding protein RFX.

Major histocompatibility complex (MHC) class II deficiency, or bare lymphocyte syndrome (BLS), is a disease of gene regulation. Patients with BLS have been classified into at least three complementation groups (A, B, and C) believed to correspond to three distinct MHC class II regulatory genes. The elucidation of the molecular basis for this disease will thus clarify the mechanisms controlling the complex regulation of MHC class II genes. Complementation groups B and C are characterized by a lack of binding of RFX, a nuclear protein that normally binds specifically to the X box cis-acting element present in the promoters of all MHC class II genes. We have now purified RFX to near homogeneity by affinity chromatography. Using an in vitro transcription system based on the HLA-DRA promoter, we show here that extracts from RFX-deficient cells from patients with BLS (BLS cells) in groups B and C, which are transcriptionally inactive in this assay, can be complemented to full transcriptional activity by the purified RFX. As expected, purified RFX also restores a completely normal pattern of X box-binding complexes in these mutant extracts. This provides the first direct functional evidence that RFX is an activator of MHC class II gene transcription and that its absence is indeed responsible for the regulatory defect in MHC class II gene expression in patients with BLS.

Base Sequence↗
PubMed1994

Cardiopulmonary resuscitation. Paper 2: A survey of basic life support training for medical students.

This paper presents the results of a survey of Basic Life Support (BLS) training, based on experience gained by undergraduate medical students who had just completed their first clinical year (third year) at the University of Glasgow. Data were collected on the amount and quality of BLS training received, along with students' own perceptions of their confidence in providing BLS in a cardiac arrest resuscitation attempt. The results made interesting, but not surprising, reading with only 15% of students appearing to have been adequately taught BLS at any point during their third year. Students want more training and 98% see resuscitation as an important topic in the curriculum. Self-perceived confidence in performing BLS in an acute resuscitation situation is low. With no evidence to suggest that the situation is any different elsewhere in the UK, it is recommended that undergraduate resuscitation training is improved to reflect the importance that medical students attach to it.

Attitude of Health Personnel↗
PubMed2005

The evaluation of first aid and basic life support training for the first year university students.

In Turkey, the first aiders are few in quantity and yet they are required in many settings, such as earthquakes. It was thought that training first year university students in first aid and basic life support (FA-BLS) techniques would serve to increase the number of first aiders. It was also thought that another problem, the lack of first aid trainers, might be addressed by training medical students to perform this function. A project aimed at training first year university students in FA-BLS was conducted at Hacettepe University. In the first phase, medical student first aid trainers (MeSFAT) were trained in FA-BLS training techniques by academic trainers and in the second phase, first year university students were trained in FA-BLS techniques by these peer trainers under the academic trainers' supervision. The purpose of this study was to assess the participants' evaluation of this project and to propose a new program to increase the number of first aiders in the country. In total, 31 medical students were certified as MeSFATs and 12 of these trained 40 first year university students in FA-BLS. Various questionnaires were applied to the participants to determine their evaluation of the training program. Most of the participants and the authors considered the program to be successful and effective. This method may be used to increase the number of first aid trainers and first aiders in the community.

Adolescent↗
PubMed1975

[Adherence of pathogenic Escherichia coli to epithelial cells isolated from the intestinal mucosa of the rabbit, inhibiting effect of hyperimmune bovine colostrum and of various carbohydrates (author's transl)].

In order to study the mode of action of a bovine anti-Escherichia coli lactoserum (BLS), we have used a new test measuring the adherence of pathogenic E. coli on epithelial cells isolated from the small intestine of rabbit. A mixed suspension of E. coli and of epithelial cells is incubated for 15 min and the number of bacteria adhering to the cells counted under the microscope. The BLS at a concentration of 3.5 mg/ml IgG is able to reduce this number by a factor of 3-5. After absorption of the BLS with formaldehyde-treated bacteria, this factor is smaller than 2. At a concentration of 5 mg/ml, D-mannose and alpha-methylmannoside are as efficient inhibitors of adherence as BLS; at the same concentration, L-mannose is ineffective. The cultures of E. coli strongly agglutinating guinea pig erythrocytes, adhere to a larger extent to the epithelial cells. The last two observations confirm the important role played by fimbriae for the adhesive properties of E. coli. The presence of fimbrial antibodies would partially explain the inhibiting effect of BLS on adherence.

Animals↗
PubMed1980

Rate of sister chromatid exchanges in Bloom syndrome fibroblasts reduced by co-cultivation with normal fibroblasts.

Six strains of Bloom syndrome (BlS) fibroblasts responded to co-cultivation with normal fibroblasts at a 1:2 ratio by a reduced rate of sister chromatid exchanges (SCE's) from a mean of 67.5 (range = 59--78) to 28.4 (range = 21--35). The response was dose-dependent in one strain tested at 1:2, 1:1, and 2:1 ratios. In addition, quadriradial exchange figures and other signs of increased chromosomal instability were not found in BlS cells following co-cultivation with control cells. Control cells did not respond to BlS cells and maintained a normal rate of SCEs. Culture medium conditioned for 48 hrs by normal fibroblasts could also reduce the rate of SCEs in BlS fibroblasts, but less than in co-cultivation. We suggest that the reduced rate of SCEs and the lack of chromosomal instability in BlS cells following co-cultivation represent a corrective effect that is related to the basic defect and not dependent on cell-to-cell contact.

Adolescent↗
PubMed1995

Emergency cardiac care. Moral, legal, and ethical considerations.

According to the American Heart Association, "Successful completion of an ACLS course means in accordance with the cognitive and performance standards of the American Heart Association. It does not warrant performance, nor does it, per se, qualify or authorize a person to perform any procedure. It in no way related to licensure, which is a function of the appropriate legislative, health or educational authority." The same can be said for BLS; however, with the recent revisions in ECC programs, even this disclaimer has been eliminated from the most recent textbooks in BLS and ACLS. This is in keeping with "...the American Heart Association's reaffirmation of its role as an educational resource rather than as a certifying agency." Lay public course participants in BLS (which technically includes dentists) will now receive course participation cards. Health care provider course participants will continue to receive "course completion cards" if all criteria have been satisfied by the student. The trend is to categorize what was previously termed testing as evaluation. Certification has become a thing of the past. It is unclear at this time what the impact this policy change will have on agencies who rely upon documentation from the American Heart Association to satisfy requirements that have been imposed upon dentists and other health professionals for initial licensure and relicensure. Semantics aside, one thing that remains clear is the expectation of the dentist with regards to emergency management. Expertise (for lack of a better term) in specific aspects of ECC remains a standard. For all dentists, expertise in BLS is that standard. For dentists administering deep sedation and general anesthesia, expertise in ACLS is the community standard. Although there is some ambiguity for those dentists administering conscious sedation, at the very least, they should have expertise in BLS. In addition, they are strongly encouraged to have expertise in ACLS, particularly because the limited hours of training in conscious sedation provide less medical background than is acquired during training in deep sedation and general anesthesia. In addition, the dentist is ultimately responsible for the demeanor of his or her office and staff. In the prehospital dental office setting, the matter of converting a dental office team geared to efficient delivery of dental procedures, into a team primed to perform emergency cardiac care seems daunting. This is especially so if the dentist has little undergraduate or clinical preparation for managing life-threatening emergencies. Therefore, an emergency management plan (with oversight for its implementation by the dentist) is of paramount importance.

Anesthesia, Dental↗
PubMed1996

[Basic Life Support: the primary ABC(D) of cardiopulmonary resuscitation].

Basic Life Support [BLS] includes both prompt recognition and immediate support of ventilation and circulation in case of respiratory or cardiac arrest. The major objective of BLS is to provide oxygen to the heart and the brain and to sustain tissue viability until definitive electrical or medical treatment [Advanced Cardiac Life Support = ACLS] can restore spontaneous circulation. BLS focuses on the primary survey A B C [D]: Airway [to open the airway]-Breath [to assess the presence or absence of spontaneous breathing and to provide ventilation]-Circulation [to assess pulselessness and to perform chest compression-Defibrillation [might perhaps no longer belong solely to ACLS because of the widespread availability of Automade External Defibrillators]. The key for successful ACLS, especially defibrillation, is the prompt initiation of correct rescue breathing, and correct chest compressions in a patient with a cardiac arrest. Promptly and optimally performed BLS is most effective and one major key to save life, thus, both family physicians and specialists must be able to administer optimal BLS-survival will be poor if one link in the chain of survival is inadequate!

Awareness↗
PubMed1993

Antigen processing and presentation by EBV-carrying cell lines: cell-phenotype dependence and influence of the EBV-encoded LMP1.

Burkitt's-lymphoma (BL) lines which have maintained in vitro the tumor-cell phenotype (group-I BLs) are poor antigen-presenting cells (APC), in spite of a relatively high surface expression of MHC class II. In order to investigate the mechanism of this deficiency, we have compared group-I BL lines, their sub-lines which have progressed in vitro towards an LCL-like phenotype (group-III BLs), and EBV-transformed lymphoblastoid cell lines (LCLs), for their ability to bind and process tetanus toxoid (TT). The uptake and internalization of 125I-labelled TT was equivalent in the 3 cell types. Only LCLs and group-III BL lines were able to process the TT, as shown by the identification of discrete proteolytic products after separation of whole-cell extracts in tricine-SDS-polyacrylamide gels, and by the recovery of TCA-soluble radioactivity in the culture supernatant. Processing of TT was induced by expression of the EBV-encoded membrane protein LMP 1 in transfected group-1 BLs. The present findings suggest that the inability of group-1 BLs to act as APC is due to their failure to process exogenous antigens. This function appears to be related to phenotypic properties that can be modulated by the expression of LMP1.

Antigen-Presenting Cells↗
PubMed2005

Liver iron concentration evaluated by two magnetic methods: magnetic resonance imaging and magnetic susceptometry.

Quantification of liver iron concentration (LIC) is crucial in the management of patients suffering from certain pathologies that can produce iron overload, such as Cooley's anemia and hemochromatosis. All of these patients must control the level of iron deposits in their organs to avoid the toxicity of high LIC, which is potentially lethal. This paper describes experimental protocols for LIC measurement using two magnetic techniques: magnetic resonance imaging (MRI) and biomagnetic liver susceptometry (BLS). MRI proton transverse relaxation rate (R2) and image intensity, evaluated pixel by pixel, were used as indicators of iron load in the tissue. LIC measurement by BLS was performed using an AC superconducting susceptometer system. A group of 23 patients with a large range of iron overload (0.9 to 34.5 mgFe/g(dry tissue)) was evaluated with both techniques (MRI x BLS). A significant linear correlation (r = 0.89-0.95) was found between the LIC by MRI and by BLS. These results show the feasibility of using two noninvasive methodologies to evaluate liver iron store in a large concentration range. Both methodologies represent an equivalent precision.

Adolescent↗
PubMed1975

Passive oral immunization with bovine immunoglobulins: enterpathogenic Escherichia coli from infants and bovine anti-E. coli lactoserum assayed in the rabbit ileal loop model.

The effect of immune bovine lactoserum (BLS) antipolyvalent enteropathogenic Escherichia coli on bacterial growth, viability and bacteria-induced fluid accumulation was examined in rabbit ileal loops. Human enteropathogenic E. coli strains 0125:K70 (B15), 0111:K58 (B4) and 055:K59 (B5) (1-3 X 10(9) per inoculum) induced secretion of 4-6 ml fluid per 10 cm loop. This effect was inhibited effectively by BLS (corresponding to 50 mg IgG 1 per loop) while the viability of bacteria counts decreased 2-25 fold compared with bovine serum albumin. E. coli 026:K60 (B6), 0126:K71 (B16) and 0127:K63 (B8) caused moderate secretion (2-3 ml/10 cm loop) that was significantly neutralized by BLS. E. coli 086:K61 (B7) and 0128:K67 (B12) did not give positive loops. The fluid secretion was shown to be dose dependent for E. coli 0125:K70 (B15) over the range from 2.5 X 10(9) to 8 X 10(7) bacteria/loop. The titration of the effect of BLS on fluid secretion caused by the same strain revealed a dose dependent decrease. The best inhibition was obtained with 100 mg BLS/loop, the highest dose tested.

Animals↗
PubMed1994

[Initial defibrillation by emergency physicians or by first aid assistants? A prospective, comparative multicenter study in outpatients with ventricular fibrillation].

In a controlled prospective randomized study, defibrillation by emergency medical technicians (EMTs) was compared with the current standard of care in Germany (basic life support by EMTs and defibrillation by emergency physicians only) in order to answer the following questions: 1. Does EMT defibrillation improve the survival rate and long-term prognosis of patients in ventricular fibrillation as compared to the current German standards in resuscitation (basic life support by EMTs and defibrillation by emergency physicians)? 2. Are the prerequisites for the use of semiautomatic defibrillators fulfilled in the emergency medical systems (EMS) of the participating centers? METHODS. The study phase includes randomization of 121 adult patients with witnessed cardiac arrest and ventricular fibrillation (VF) as first ECG rhythm. Prior to the onset of the study, all EMTs of the participating EMS systems were retrained in basic life support (BLS) measures. In each center, randomly assessed EMT-Ds (EMTs trained in Defibrillation) were trained to use semiautomatic defibrillators. With the help of one-line tape recording, the time intervals during resuscitation and treatment steps were evaluated. Successfully resuscitated patients were followed up with the help of the Glasgow Coma Scale and the Pittsburgh Cerebral and Overall Performance Categories. RESULTS. From 1 February 1991 until 28 June 1992, 159 patients with VF were randomized. In 121 cases, collapse was witnessed. 25% (14/57) of the patients receiving defibrillation by EMT-Ds (study group = S) were discharged from the hospital alive. In the control group, 52 patients were defibrillated by emergency physicians, following BLS by EMTs [control group 1 = C1; discharged: 29% (15/52)]. Fifty patients received BLS and advanced cardiac life support (ACLS) by the emergency physicians crews [control group 2 = C2; discharged: 18% (9/20)]. In the study group, the median time interval from collapse of the patient until initiation of BLS measures was 7.7 min, 7 min in C1 and 8 min in C2. ACLS measures were initiated significantly earlier (P < 0.05) in the control groups, as compared to the study group [S: 13 min, C1: 11 min; C2: 10.3 min]. Sixty-seven percent (30/45) of the study patients and 46% (36/76) of the control patients were defibrillated within 12 min. Study patients were defibrillated earlier (P < 0.05) (S: 9.9 min; C1: 12.2 min; C2: 12.75 min); return of spontaneous circulation (ROSC) was achieved earlier (P < 0.05) in the study group [S: 14 min; C1: 19 min; C2: 18.2 min] and the number of patients in the study group requiring no epinephrine during resuscitation was higher (P < 0.01) than in the control groups [S: 35.3% (12/34); C1: 10% (4/40); C2: 10.5% (4/38)]. Furthermore, the total amount of epinephrine [mean (+/- standard error)] administered in the study group [S: 2.35 (+/- 0.49) mg; C1: 6.71 (+/- 0.98) mg; C2: 7.71 (+/- 1.31) mg] was significantly lower (P < 0.05). No significant differences in neurological long-term prognosis were found for the groups investigated. CONCLUSION. Neither the initial survival rate the number of patients discharged alive, nor the neurological long-term prognosis was significantly different for any of the groups investigated. Because of apparent differences in indirect prognostic parameters (time interval until ROSC, number of patients requiring no epinephrine) and because of the fact that the time interval to the first defibrillation was reduced by EMT defibrillation, EMT-Ds may perform defibrillation if: (a) they reach the patient before the emergency physician and (b) if they are trained intensively and supervised continuously. In order to increase the efficiency of defibrillation by EMT-Ds, far-reaching changes in our EMS are mandatory: (a) a reduction in the time interval from collapse until initiation of BCLS measures by intensifying layperson CPR training; (b) an increase in the number of emergency units equipped with semiautomatic defibril

Electric Countershock↗
PubMed2005

Evolutionary conservation and characterization of the bare lymphocyte syndrome transcription factor RFX-B and its paralogue ANKRA2.

The extraordinary homology between major histocompatibility complex class II (MHC II) proteins across species from human to bony fish suggests that transcription factors that regulate these proteins might be conserved as well. Deficiencies in four proteins that regulate MHC II genes in humans (RFX-B, RFX5, RFXAP, and CIITA) cause an inherited immunodeficiency disorder known as the bare lymphocyte syndrome (BLS). To understand the structure and mechanism of function of the BLS transcription factors, we analyzed the evolutionary history of RFX-B, the factor deficient in the majority of patients with BLS. Sequence comparison and analysis of the RFX-B proteins showed that RFX-B and a closely related protein, ANKRA2, are present in humans to bony fish and that specific domains are highly conserved. In addition to sequence conservation, functional conservation exists, as mouse and Xenopus RFX-B orthologues, but not the paralogous protein ANKRA2, were able to complement the MHC II deficiency in a BLS-patient-derived cell line deficient in RFX-B. The remarkable conservation of the RFX-B lineage attests to the conservation of the regulation mechanism for this gene system and its importance to precisely regulate MHC class II molecules in both the developing and active immune response.

Amino Acid Sequence↗