Feasibility and Validity of the Coma Recovery Scale-Revised for Accelerated Standardized Testing: A Practical Assessment Tool for Detecting Consciousness in the Intensive Care Unit

We developed and validated an abbreviated version of the Coma Recovery Scale-Revised (CRS-R), the CRS-R For Accelerated Standardized Testing (CRSR-FAST), to detect conscious awareness in patients with severe traumatic brain injury in the intensive care unit. In 45 consecutively enrolled patients, CRSR-FAST administration time was approximately one-third of the full-length CRS-R (mean [SD] 6.5 [3.3] vs 20.1 [7.2] minutes, p < 0.0001). Concurrent validity (simple kappa 0.68), test-retest (Mak's ρ = 0.76), and interrater (Mak's ρ = 0.91) reliability were substantial. Sensitivity, specificity, and accuracy for detecting consciousness were 81%, 89%, and 84%, respectively. The CRSR-FAST facilitates serial assessment of consciousness, which is essential for diagnostic and prognostic accuracy. ANN NEUROL 2023;94:919-924.

Method for quantifying arousal and consciousness in healthy states and severe brain injury via EEG-based measures of corticothalamic physiology

BACKGROUND

Characterization of normal arousal states has been achieved by fitting predictions of corticothalamic neural field theory (NFT) to electroencephalographic (EEG) spectra to yield relevant physiological parameters.

NEW METHOD

A prior fitting method is extended to distinguish conscious and unconscious states in healthy and brain injured subjects by identifying additional parameters and clusters in parameter space.

RESULTS

Fits of NFT predictions to EEG spectra are used to estimate neurophysiological parameters in healthy and brain injured subjects. Spectra are used from healthy subjects in wake and sleep and from patients with unresponsive wakefulness syndrome, in a minimally conscious state (MCS), and emerged from MCS. Subjects cluster into three groups in parameter space: conscious healthy (wake and REM), sleep, and brain injured. These are distinguished by the difference X-Y between corticocortical (X) and corticothalamic (Y) feedbacks, and by mean neural response rates α and β to incoming spikes. X-Y tracks consciousness in healthy individuals, with smaller values in wake/REM than sleep, but cannot distinguish between brain injuries. Parameters α and β differentiate deep sleep from wake/REM and brain injury.

COMPARISON WITH EXISTING METHODS

Other methods typically rely on laborious clinical assessment, manual EEG scoring, or evaluation of measures like Φ from integrated information theory, for which no efficient method exists. In contrast, the present method can be automated on a personal computer.

CONCLUSION

The method provides a means to quantify consciousness and arousal in healthy and brain injured subjects, but does not distinguish subtypes of brain injury.

Noninvasive Brain Stimulation Therapies to Promote Recovery of Consciousness: Where We Are and Where We Should Go

Therapeutic options for patients with disorders of consciousness (DoC) are still underexplored. Noninvasive brain stimulation (NIBS) techniques modulate neural activity of targeted brain areas and hold promise for the treatment of patients with DoC. In this review, we provide a summary of published research using NIBS as therapeutic intervention for DoC patients, with a focus on (but not limited to) randomized controlled trials (RCT). We aim to identify current challenges and knowledge gaps specific to NIBS research in DoC. Furthermore, we propose possible solutions and perspectives for this field. Thus far, the most studied technique remains transcranial electrical stimulation; however, its effect remains moderate. The identified key points that NIBS researchers should focus on in future studies are (1) the lack of large-scale RCTs; (2) the importance of identifying the endotypes of responders; and (3) the optimization of stimulation parameters to maximize the benefits of NIBS.

Transcranial Pulsed-Current Stimulation versus Transcranial Direct Current Stimulation in Patients with Disorders of Consciousness: A Pilot, Sham-Controlled Cross-Over Double-Blind Study

Transcranial direct-current stimulation (tDCS) over the prefrontal cortex can improve signs of consciousness in patients in a minimally conscious state. Transcranial pulsed-current stimulation (tPCS) over the mastoids can modulate brain activity and connectivity in healthy controls. This study investigated the feasibility of tPCS as a therapeutic tool in patients with disorders of consciousness (DoC) and compared its neurophysiological and behavioral effects with prefrontal tDCS. This pilot study was a randomized, double-blind sham-controlled clinical trial with three sessions: bi-mastoid tPCS, prefrontal tDCS, and sham. Electroencephalography (EEG) and behavioral assessments were collected before and after each stimulation session. Post minus pre differences were compared using Kruskal-Wallis and Wilcoxon signed-rank tests. Twelve patients with DoC were included in the study (eight females, four traumatic brain injury, 50.3 ± 14 y.o., 8.8 ± 10.5 months post-injury). We did not observe any side-effects following tPCS, nor tDCS, and confirmed their feasibility and safety. We did not find a significant effect of the stimulation on EEG nor behavioral outcomes for tPCS. However, consistent with prior findings, our exploratory analyses suggest that tDCS induces behavioral improvements and an increase in theta frontal functional connectivity.

Subcutaneous injection of an immunologically tolerated protein up to 5 days before skin injuries improves wound healing

Oral tolerance blocks the development of specific immune responses to proteins ingested by the oral route. One of the first registries of oral tolerance showed that guinea pigs fed corn became refractory to hypersensitivity to corn proteins. Mice fed with chow containing corn are tolerant to zein, and parenteral injection of zein plus adjuvant blocks immunization to unrelated proteins injected concomitantly and reduces unspecific inflammation. Extensive and prolonged inflammatory infiltrate in the wound bed is one of the causes of pathological wound healing. Previous research shows that intraperitoneal injection of zein concomitant with skin injuries reduces the inflammatory infiltrate in the wound bed and improves wound healing. Herein, we tested if one subcutaneous injection of zein before skin injury improves wound healing. We also investigated how long the effects triggered by zein could improve skin wound healing. Mice fed zein received two excisional wounds on the interscapular skin under anesthesia. Zein plus Al(OH)₃ was injected at the tail base at 10 min, or 3, 5, or 7 days before skin injuries. Wound healing was analyzed at days 7 and 40 after injury. Our results showed that a zein injection up to 5 days before skin injury reduced the inflammatory infiltrate, increased the number of T-cells in the wound bed, and improved the pattern of collagen deposition in the neodermis. These findings could promote the development of new strategies for the treatment and prevention of pathological healing using proteins normally found in the common diet.

Diagnosing Level of Consciousness: The Limits of the Glasgow Coma Scale Total Score

In nearly all clinical and research contexts, the initial severity of a traumatic brain injury (TBI) is measured using the Glasgow Coma Scale (GCS) total score. However, the GCS total score may not accurately reflect level of consciousness, a critical indicator of injury severity. We investigated the relationship between GCS total scores and level of consciousness in a consecutive sample of 2,455 adult subjects assessed with the GCS 69,487 times as part of the multi-center Transforming Research and Clinical Knowledge in TBI (TRACK-TBI) study. We assigned each GCS subscale score combination a level of consciousness rating based upon published criteria for the following disorders of consciousness (DoC) diagnoses: coma, vegetative state/unresponsive wakefulness syndrome, minimally conscious state, and post-traumatic confusional state, and present our findings using summary statistics and four illustrative cases. Participants had the following characteristics: mean (standard deviation) age 41.9 (17.6) years, 69% male, initial GCS 3-8=13%; 9-12=5%; 13-15=82%. All GCS total scores between 4-14 were associated with more than one DoC diagnosis; the greatest variability was observed for scores of 7-11. Furthermore, a wide range of total scores were associated with identical DoC diagnoses. Importantly, a diagnosis of coma was only possible with GCS total scores of 3-6. The GCS total score does not accurately reflect level of consciousness based on published DoC diagnostic criteria. To improve the classification of patients with TBI and to inform the design of future clinical trials, clinicians and investigators should consider individual subscale behaviors and more comprehensive assessments when evaluating TBI severity.

A novel closed-loop EEG-tDCS approach to promote responsiveness of patients in minimally conscious state: A study protocol

Transcranial direct current stimulation (tDCS) applied over the prefrontal cortex has been shown to improve behavioral responsiveness in patients with disorders of consciousness following severe brain injury, especially those in minimally conscious state (MCS). However, one potential barrier of clinical response to tDCS is the timing of stimulation with regard to the fluctuations of vigilance that characterize this population. Indeed, a previous study showed that the vigilance of MCS patients has periodic average cycles of 70 min (range 57-80 min), potentially preventing them to be in an optimal neural state to benefit from tDCS when applied randomly. To tackle this issue, we propose a new protocol to optimize the application of tDCS by selectively stimulating at high and low vigilance states. Electroencephalography (EEG) real-time spectral entropy will be used as a marker of vigilance and to trigger tDCS, in a closed-loop fashion. We will conduct a randomized controlled crossover clinical trial on 16 patients in prolonged MCS who will undergo three EEG-tDCS sessions 5 days apart (1. tDCS applied at high vigilance; 2. tDCS applied at low vigilance; 3. tDCS applied at a random moment). Behavioral effects will be assessed using the Coma Recovery Scale-Revised at baseline and right after the stimulations. EEG will be recorded throughout the session and for 30 min after the end of the stimulation. This unique and novel approach will provide patients' tailored treatment options, currently lacking in the field of disorders of consciousness.

Preservation of Brain Activity in Unresponsive Patients Identifies MCS Star

Objective

Brain‐injured patients who are unresponsive at the bedside (ie, vegetative state/unresponsive wakefulness syndrome – VS/UWS) may present brain activity similar to patients in minimally conscious state (MCS). This peculiar condition has been termed “non‐behavioural MCS” or “MCS*”. In the present study we aimed to investigate the proportion and underlying brain characteristics of patients in MCS*.

Methods

Brain ¹⁸F‐fluorodeoxyglucose Positron Emission Tomography (FDG‐PET) was acquired on 135 brain‐injured patients diagnosed in prolonged VS/UWS (n = 48) or MCS (n = 87). From an existing database, relative metabolic preservation in the fronto‐parietal network (measured with standardized uptake value) was visually inspected by three experts. Patients with hypometabolism of the fronto‐parietal network were labelled “VS/UWS”, while its (partial) preservation either confirmed the behavioural diagnosis of “MCS” or, in absence of behavioural signs of consciousness, suggested a diagnosis of “MCS*”. Clinical outcome at 1‐year follow‐up, functional connectivity, grey matter atrophy, and regional brain metabolic patterns were investigated in the three groups (VS/UWS, MCS* and MCS).

Results

67% of behavioural VS/UWS presented a partial preservation of brain metabolism (ie, MCS*). Compared to VS/UWS patients, MCS* patients demonstrated a better outcome, global functional connectivity and grey matter preservation more compatible with the diagnosis of MCS. MCS* patients presented lower brain metabolism mostly in the posterior brain regions compared to MCS patients.

Interpretation

MCS* is a frequent phenomenon that is associated with better outcome and better brain preservation than the diagnosis of VS/UWS. Complementary exams should be provided to all unresponsive patients before taking medical decisions. ANN NEUROL 2021;90:89–100

SECONDs Administration Guidelines: A Fast Tool to Assess Consciousness in Brain-injured Patients

Establishing an accurate diagnosis is crucial for patients with disorders of consciousness (DoC) following a severe brain injury. The Coma Recovery Scale-Revised (CRS-R) is the recommended behavioral scale for assessing the level of consciousness among these patients, but its long duration of administration is a major hurdle in clinical settings. The Simplified Evaluation of CONsciousness Disorders (SECONDs) is a shorter scale that was developed to tackle this issue. It consists of six mandatory items, observation, command-following, visual pursuit, visual fixation, oriented behaviors, and arousal, and two conditional items, communication and localization to pain. The score ranges between 0 and 8 and corresponds to a specific diagnosis (i.e., coma, unresponsive wakefulness syndrome, minimally conscious state minus/plus, or emergence from the minimally conscious state). A first validation study on patients with prolonged DoC showed high concurrent validity and intra- and inter-rater reliability. The SECONDs requires less training than the CRS-R and its administration lasts about 7 minutes (interquartile range: 5-9 minutes). An additional index score allows the more precise tracking of a patient's behavioral fluctuation or evolution over time. The SECONDs is therefore a fast and valid tool for assessing the level of consciousness in patients with severe brain injury. It can easily be used by healthcare staff and implemented in time-constrained clinical settings, such as intensive care units, to help decrease misdiagnosis rates and to optimize treatment decisions. These administration guidelines provide detailed instructions for administering the SECONDs in a standardized and reproducible manner, which is an essential requirement for achieving a reliable diagnosis.

Behavioral and electrophysiological effects of network-based frontoparietal tDCS in patients with severe brain injury: A randomized controlled trial

•

Behavioral and EEG effects of multifocal frontoparietal tDCS are investigated in patients with severe brain injury.

•

No behavioral treatment effect was identified at the group level while EEG complexity increased in low frequency bands.

•

Electrophysiological changes were not translated into behavioral changes at the group level.

Background

Transcranial direct current stimulation (tDCS) may promote the recovery of severely brain-injured patients with disorders of consciousness (DOC). Prior tDCS studies targeted single brain regions rather than brain networks critical for consciousness recovery.

Objective

Investigate the behavioral and electrophysiological effects of multifocal tDCS applied over the frontoparietal external awareness network in patients with chronic acquired DOC.

Methods

Forty-six patients were included in this randomized double-blind sham-controlled crossover trial (median [interquartile range]: 46 [35 – 59] years old; 12 [5 – 47] months post injury; 17 unresponsive wakefulness syndrome, 23 minimally conscious state (MCS) and 6 emerged from the MCS). Multifocal tDCS was applied for 20 min using 4 anodes and 4 cathodes with 1 mA per electrode. Coma Recovery Scale-Revised (CRS-R) assessment and 10 min of resting state electroencephalogram (EEG) recordings were acquired before and after the active and sham sessions.

Results

At the group level, there was no tDCS behavioral treatment effect. However, following active tDCS, the EEG complexity significantly increased in low frequency bands (1–8 Hz). CRS-R total score improvement was associated with decreased baseline complexity in those bands. At the individual level, after active tDCS, new behaviors consistent with conscious awareness emerged in 5 patients. Conversely, 3 patients lost behaviors consistent with conscious awareness.

Conclusion

The behavioral effect of multifocal frontoparietal tDCS varies across patients with DOC. Electrophysiological changes were observed in low frequency bands but not translated into behavioral changes at the group level.

Neurophysiological Correlates of a Single Session of Prefrontal tDCS in Patients with Prolonged Disorders of Consciousness: A Pilot Double-Blind Randomized Controlled Study

Background. Transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex (lDLPFC) was reported to promote the recovery of signs of consciousness in some patients in a minimally conscious state (MCS), but its electrophysiological effects on brain activity remain poorly understood. Objective. We aimed to assess behavioral (using the Coma Recovery Scale-Revised; CRS-R) and neurophysiological effects (using high density electroencephalography; hdEEG) of lDLPFC-tDCS in patients with prolonged disorders of consciousness (DOC). Methods. In a double-blind, sham-controlled, crossover design, one active and one sham tDCS (2 mA, 20 min) were delivered in a randomized order. Directly before and after tDCS, 10 min of hdEEG were recorded and the CRS-R was administered. Results. Thirteen patients with severe brain injury were enrolled in the study. We found higher relative power at the group level after the active tDCS session in the alpha band in central regions and in the theta band over the frontal and posterior regions (uncorrected results). Higher weighted symbolic mutual information (wSMI) connectivity was found between left and right parietal regions, and higher fronto-parietal weighted phase lag index (wPLI) connectivity was found, both in the alpha band (uncorrected results). At the group level, no significant treatment effect was observed. Three patients showed behavioral improvement after the active session and one patient improved after the sham. Conclusion. We provide preliminary indications that neurophysiological changes can be observed after a single session of tDCS in patients with prolonged DOC, although they are not necessarily paralleled with significant behavioral improvements.

Anti-inflammatory and immune properties of the peltatoside, isolated from the leaves of Annona crassiflora Mart., in a new experimental model zebrafish

Establishing new animal models for the study of inflammation is very important in the process of discovering new drugs, since the inflammatory event is the basis of many pathological processes. Whereas rodent models have been the primary focus of inflammation research, we defend the zebrafish (Danio rerio) test as a feasible alternative for preclinical studies. Moreover, despite all the technological development already achieved by humanity, nature can still be considered a relevant source of new medicines. In this context, the aim of this work was to evaluate the anti-inflammatory effect of a substance isolated from the medicinal plant Annona crassilfora Mart, the peltatoside, in an inflammatory model of zebrafish. It was determined: (i) total leukocyte count in the coelomate exudate; (ii) N-acetyl-β-d-glucuronidase (NAG); (iii) myeloperoxidase (MPO); (iv) and the histology of liver, intestine and mesentery. Peltotoside (25, 50 and 100 μg) and dexamethasone (25 μg) were administered intracelomatically (i.c.) 30 min before carrageenan (i.c.). Pretreatment with peltatoside at three doses significantly inhibited leukocyte recruitment in the coelomic cavity, and inhibited NAG and MPO activity against the action of Cg, in a similar manner as dexamethasone. However, some microlesions in the evaluated organs were detected. The dose of 25 μg showed an anti-inflammatory effect with lower undesirable effects in the tissues. Our results suggest that the zebrafish test was satisfactory in performing our analyzes and that the peltotoside has a modulatory action in reducing leukocyte migration.

Tunable Magnetoelastic Effects in Voltage-Controlled Exchange-Coupled Composite Multiferroic Microstructures

The magnetoelectric properties of exchange-coupled Ni/CoFeB-based composite multiferroic microstructures are investigated. The strength and sign of the magnetoelastic effect are found to be strongly correlated with the ratio between the thicknesses of two magnetostrictive materials. In cases where the thickness ratio deviates significantly from one, the magnetoelastic behavior of the multiferroic microstructures is dominated by the thicker layer, which contributes more strongly to the observed magnetoelastic effect. More symmetric structures with a thickness ratio equal to one show an emergent interfacial behavior which cannot be accounted for simply by summing up the magnetoelastic effects occurring in the two constituent layers. This aspect is clearly visible in the case of ultrathin bilayers, where the exchange coupling drastically affects the magnetic behavior of the Ni layer, making the Ni/CoFeB bilayer a promising next-generation synthetic magnetic system entirely. This study demonstrates the richness and high tunability of composite multiferroic systems based on coupled magnetic bilayers compared to their single magnetic layer counterparts. Furthermore, because of the compatibility of CoFeB with present magnetic tunnel junction-based spintronic technologies, the reported findings are expected to be of great interest for the development of ultralow-power magnetoelectric memory devices.

Single tDCS session of motor cortex in patients with disorders of consciousness: a pilot study

Primary Objective: Patients with disorders of consciousness (DOC) face a lack of treatments and risk of misdiagnosis, potentially due to motor impairment. Transcranial direct current stimulation (tDCS) showed promising results over the prefrontal cortex in DOC and over the primary motor cortex (M1) in stroke. Tis pilot study aimed at evaluating the behavioral effects of M1 tDCS in patients with DOC.Research Design: In this randomized double-blind sham-controlled crossover trial, we included 10 patients (49 ± 22 years, 7 ± 13 months since injury, 4 unresponsive wakefulness syndrome, 6 minimally conscious state, 5 traumatic etiologies).Methods and Procedures: One session of tDCS (2 mA for 20 min) and one session of sham tDCS were applied over M1 in a randomized order with a washout period of minimum 24 h and behavioral effects were assessed using the CRS-R. At the group level, no treatment effect was identified on the total score (p = .55) and on the motor subscale (p = .75). Two patients responded to tDCS by showing a new sign of consciousness (visual pursuit and object localization).Conclusions: One session of M1 tDCS failed to improve behavioral responsiveness in patients with DOC. Other application strategies should be tested.

Cocaine use disorders and serum magnesium profile

INTRODUCTION

Magnesium influences the nervous system via its actions on the release and metabolism of neurotransmitters, and abnormal magnesium metabolism has been implicated in several neuropsychiatric disorders with prominent mood symptoms. The aim of this study was to compare the serum levels of magnesium of cocaine addicts to those of heroin addicts and normal controls. We also attempted to clarify the relationship between the pathophysiology of cocaine abuse and magnesium levels by investigating their association with various clinical dimensions.

METHODS

Eighty-five consecutive subjects with a history of cocaine or opiate use disorders were recruited, evaluated and compared with 100 controls. The cocaine and heroin abusers were assessed with a 10-cm Visual Analogue Scale, the Symptom Check List-90 Revised, the Brown-Goodwin Scale, and the Barrat Impulsiveness Scale.

RESULTS

Magnesium levels were higher in the cocaine group compared to the opiate group and control. Male subjects had lower magnesium levels than the females of all three groups. Scores of impulsiveness, aggressiveness, craving and psychiatric symptomatology were not significantly different between the opiate and cocaine addicts.

DISCUSSION

This is the first study evaluating the magnesium level in cocaine addicts. Cocaine addicts showed higher total plasma magnesium levels than opiate addicts and normal controls, even though they remained in the normal range. The roles of the psychiatric comorbidity, of a pharmacokinetic association and of a pharmacodynamic interaction are discussed. Further prospective studies comparing serum levels of cocaine at different times are needed.

Organizational models of emergency psychiatric intervention: state of the art

Authors outline the differences between medical and psychiatric definition of emergency and analyze different organizational models of psychiatric intervention in Emergency Room. The historical evolution changed these models, and the relation with services for acute and subacute patients in hospital and community services. The Italian reform model is compared with the slow deinstitutionalization of psychiatry in other countries. Critical points in Italian emergency organization after the Psychiatric Reform are pointed out: low number of beds for acute patients, difficulties and delays in transfer from Emergency Room to GHPW (General Hospital Psychiatric Ward), waiting lists for voluntary treatments. To overcome some of these problems, the Authors propose that even in hospitals without psychiatric ward, a small unit of short psychiatric observation be implemented, for voluntary treatments, before transfer to other institutions.

Freshly isolated Valpha24+ CD4+ invariant natural killer T cells activated by alpha-galactosylceramide-pulsed B cells promote both IgG and IgE production

CD1d-restricted invariant natural killer T (iNK T) cells activated by their experimental ligand alpha-galactosylceramide (alpha-GC) can produce both T helper 1 (Th1) and Th2 cytokines and display regulatory functions. Recent studies identified CD4(+) and CD4(-) CD8(-) double-negative (DN) iNK T cells as the two major components of the human population and suggest that they display a Th2 and a Th1 profile, respectively. We compared the Th2-promoting activity of freshly isolated human CD4(+) and DN iNK T cells in terms of their capacity to induce Ig production by autologous B cells. Secretion of IgG and IgE but not IgM was enhanced by the CD4(+) T cell subset (including iNK T cells) but not by its DN counterpart. iNK T cells were directly responsible for this pro-Th2 effect, as demonstrated by the requirement for both alpha-GC stimulation and CD1d presentation, as well as by its disappearance upon iNK T cell depletion. Interaction with iNK T cells led to progressive accumulation of isotype-switched and activated B cells. Myeloid dendritic cells (DC) completely block the induction of Ig production in co-culture. This dominant inhibitory effect of myeloid DC was concomitant with a specific loss of interleukin (IL)-4 production by CD4(+) iNK T but not by conventional T cells. These data support the conclusion that, conversely to the interferon (IFN)-gamma-producing DN human iNK T cell population, interleukin (IL)-4-producing CD4(+) iNK T cells can activate and help B cells to produce both IgG and IgE through a CD1d-dependent mechanism, in keeping with a functional Th1/Th2 dichotomy between these subsets.

Serum magnesium profile in heroin addicts: according to psychiatric comorbidity

Psychiatric comorbidity in heroin addiction can modify both the biological pattern and clinical course of this disorder. Because of the role of magnesium in neurotransmission and its specific patterns in some psychiatric conditions, such as depression and schizophrenia, we studied a sample of heroin dependent subjects, with and without psychiatric comorbidity. A sample of 162 drug addicts (123 men and 39 women, mean age 32.3 +/- 6.7) was diagnosed for the presence of psychiatric comorbidity with DSM IV criteria. They were subsequently divided in 4 subgroups: No comorbidity, Anxiety Disorders, Mood Disorders, Personality Disorders. Differences in serum magnesium level between the groups were analysed with the Anova method, with age as covariate. Results show that serum Mg++ levels are significantly higher in patients with heroin dependence and personality disorders compared to patients with depression comorbidity and without comorbidity. Psychiatric codiagnosis significantly modifies Mg++ levels in this drug dependent sample. Gender modifies Mg levels in no comorbid subjects so that females show significantly lower Mg++ levels compared to males. The presence of psychiatric comorbidity abates this difference.

A truncated form of teratocarcinoma-derived growth factor-1 (cripto-1) mRNA expressed in human colon carcinoma cell lines and tumors

The human teratocarcinoma-derived growth factor (TDGF)-1 gene encodes a 188-amino acid protein, cripto-1. The TDGF-1 gene is overexpressed in the majority of human primary colorectal carcinomas and hepatic metastases, in breast carcinomas and in testicular nonseminoma germ cell embryonal carcinomas. In the human embryonal carcinoma cell line NTERA-2 clone D1, a 2-kb TDGF-1 mRNA transcript is expressed. The present study shows that a 1.7-kb mRNA transcript lacking the first two exons of the TDGF-1 gene is expressed in the human colon carcinoma cell line GEO. This shorter mRNA is the only TDGF-1 transcript that is present in the majority of primary human colorectal carcinomas and hepatic metastases and in adult human tissues such as the pancreas, heart, stomach, mammary gland, skeletal muscle, liver and placenta. In contrast, in the kidney, brain, testis, ovary and spleen, the longer 2-kb TDGF-1 mRNA transcript is expressed. The putative shorter protein starts at a CUG codon 129 nucleotides downstream of the starting AUG codon of the longer protein. These data indicate the potential for differential transcriptional regulation of the TDGF-1 gene in different normal and tumor tissues.

Synergism between vascular endothelial growth factor and placental growth factor contributes to angiogenesis and plasma extravasation in pathological conditions

Vascular endothelial growth factor (VEGF) stimulates angiogenesis by activating VEGF receptor-2 (VEGFR-2). The role of its homolog, placental growth factor (PlGF), remains unknown. Both VEGF and PlGF bind to VEGF receptor-1 (VEGFR-1), but it is unknown whether VEGFR-1, which exists as a soluble or a membrane-bound type, is an inert decoy or a signaling receptor for PlGF during angiogenesis. Here, we report that embryonic angiogenesis in mice was not affected by deficiency of PlGF (Pgf-/-). VEGF-B, another ligand of VEGFR-1, did not rescue development in Pgf-/- mice. However, loss of PlGF impaired angiogenesis, plasma extravasation and collateral growth during ischemia, inflammation, wound healing and cancer. Transplantation of wild-type bone marrow rescued the impaired angiogenesis and collateral growth in Pgf-/- mice, indicating that PlGF might have contributed to vessel growth in the adult by mobilizing bone-marrow-derived cells. The synergism between PlGF and VEGF was specific, as PlGF deficiency impaired the response to VEGF, but not to bFGF or histamine. VEGFR-1 was activated by PlGF, given that anti-VEGFR-1 antibodies and a Src-kinase inhibitor blocked the endothelial response to PlGF or VEGF/PlGF. By upregulating PlGF and the signaling subtype of VEGFR-1, endothelial cells amplify their responsiveness to VEGF during the 'angiogenic switch' in many pathological disorders.

Structural and functional properties of membrane and secreted IgD

More than 35 years ago, study of an unknown immunoglobulin (Ig) in the serum from a myeloma patient led to the discovery of IgD. Subsequently, the finding that it also exists as a membrane-bound Ig stimulated a large number of studies during the 70s. Then, the interest on IgD shrank, largely because of the lack of known function of secretory IgD (secIgD) and of a stagnating knowledge of the functions of surface IgD. In the recent years, very significant advances followed the tremendous accumulation of data on the physiology of the B cell receptor, of which IgD is the major component, on the role of secIgD in normal and diseased individuals. This review, which is focused on human IgD but integrates data in the mouse and other species when needed, summarizes present data on the structure, synthesis and functions of both membrane and secIgD, IgD receptors and the involvement of IgD in various diseases, especially the hyperIgD syndrome.

T(h)2 cytokine dependence of IgD production by normal human B cells

IgD is a minor component of serum Ig and the control of IgD secretion is virtually unknown. We measured concentrations of IgD (and IgE and IgM as controls) in culture supernatants of peripheral blood mononuclear cells (PBMC) from 60 normal donors as well as mononuclear cells from 10 tonsils following culture in the absence or presence of CD40 mAb and cytokines. Low levels of IgD were measured in cultures of PBMC, either unstimulated or stimulated by anti-CD40 antibodies. IL-4 and IL-10 significantly increased IgD production by CD40 mAb-stimulated cells in the majority of normal subjects studied, whereas in a limited number of individuals, spontaneous IgD production was either low or high, but with no increase upon stimulation. Spontaneous IgD production by tonsil-derived mononuclear cells was higher than by PBMC and increased after CD40 stimulation and even more in the presence of IL-10, but not IL-4. IL-2 and IFN-gamma exerted a dose-dependent inhibition on spontaneous as well as CD40- and cytokine-induced IgD production by PBMC, but not by tonsil mononuclear cells. Activation by IL-4 of CD40-stimulated purified B cells from tonsil and PBMC, and by IL-10 of tonsil B cells increased IgD production, whereas IL-2 and IFN-gamma had no detectable inhibitory effect. This suggests that accessory cells indirectly regulate IgD synthesis. IgD production induced in PBMC by IL-4 or IL-10 appeared to result from an active synthesis, and correlated with an increase in the number of IgD-containing plasma cells as demonstrated by immunofluorescence and increased expression of secreted IgD transcripts. These findings suggest that IgD production by normal peripheral blood human B cells is regulated positively by T(h)2 cytokines and negatively by T(h)1 cytokines.

Assignment of human teratocarcinoma derived growth factor (TDGF) sequences to chromosomes 2q37, 3q22, 6p25 and 19q13.1

The human teratocarcinoma derived growth factor 1 (TDGF1) gene maps on chromosome (Chr) 3p21.3. One pseudogene (TDGF3) maps on Chr Xq21-->q22. We now report the nucleotide sequence and chromosome location of three additional TDGF pseudogenes. The three new sequences (TDGF2, TDGF4 and TDGF5) are truncated at the 5' end and have accumulated several point mutations, deletions and insertions. TDGF2, TDGF4 and TDGF6 map on Chrs 2q37, 6p25 and 3q22, respectively. Finally, Southern blot analysis of DNA from normal individuals shows a highly variable restriction pattern of the TDGF sequences.

Mapping of the mouse Tdgf1 gene and Tdgf pseudogenes

Teratocarcinoma-derived growth factor-1 (Tdgf1), a member of the "EGF family" of growth factors, is expressed during mouse gastrulation in the forming mesoderm and later in the truncus arteriosus of the developing heart. In humans, TDGF1 is highly expressed in germ cell tumors and in colon and mammary carcinomas. In mouse, one gene (Tdgf1) and two pseudogenes (Tdgf1-ps1 and Tdgf1-ps2) have been isolated and characterized. Tdgf1 corresponds to the gene expressed in F9 teratocarcinoma cells. Tdgf1-ps1 and Tdgf1-ps2 are two intronless sequences with all the characteristics of retroposons. In the present paper, we assign the chromosomal location for Tdgf1, Tdgf1-ps1, and Tdgf1-ps2 sequences to Chromosomes (Chrs) 9, 16, and 17, respectively. Two previously described mouse mutants, scant hair (sch) and fur deficient (fd), map near the Tdgf1 gene. Analysis of their DNA coding region provided no evidence that Tdgf1 could be the responsible gene for these phenotypes. Finally, analysis of the DNA from several Mus musculus strains and from Mus spretus mice revealed a highly variable restriction pattern and the absence of the Tdgf1-ps1 genomic sequence from the Mus spretus genome.

Placenta growth factor-1 is chemotactic, mitogenic, and angiogenic

The placental-derived growth factor (PIGF) is a dimeric glycoprotein showing a high degree of sequence similarity to the vascular endothelial growth factor. Alternative splicing of the PIGF primary transcript gives rise to two forms, named PIGF-1 and PIGF-2, which differ only in the insertion of a highly basic 21-amino acid stretch at the carboxyl end. The presence of the PIGF mRNA in thyroid, placenta, lung, and goiter has indicated the tissues where this factor functions. However, the role of PIGF in vascular development has not yet been clearly established. In the present study, we described the purification of PIGF-1 from overexpressing eukaryotic cells and then measured the angiogenic activity of the purified PIGF-1 in vivo in the rabbit cornea and the chick chorioallantoic membrane assays. In both in vivo assays, PIGF-1 induced a strong neovascularization process that was blocked by affinity-purified anti-PIGF-1 antibody. In the avascular cornea, PIGF-1 induced angiogenesis in a dose-dependent manner and seemed to be at least as effective (if not more effective) than vascular endothelial growth factor and basic fibroblast growth factor under the same conditions and at the same concentration. PIGF-1 was shown to induce cell growth and migration of endothelial cells from bovine coronary postcapillary venules and from human umbilical veins. In these two in vitro assays, PIGF-1 seemed to have a comparable effect to that of vascular endothelial growth factor and basic fibroblast growth factor on the cultured microvascular endothelium (eg, capillary venule endothelial cells). In summary, this is the first study to demonstrate that PIGF-1 can induce angiogenesis in vivo and stimulate the migration and proliferation of endothelial cells in vitro.

Mitogenic activity of new lectins from seeds of wild Artocarpus species from Vietnam

Proliferative response of human peripheral blood mononuclear cells (PBMC) stimulated by new lectins purified from seeds of differents Artocarpus species from Vietnam (A. asperulus, A. heterophyllus, A. masticata, A. melinoxylus, A. parva and A. petelotii) was studied and compared to those of the lectin jacalin purified from jackfruit (A. heterophyllus) seeds collected in the island La Réunion. All lectins stimulated human PBMC to proliferate, with a variable efficiency of the mitogenic activity. Phenotypic analysis of cells recovered after 7 day-cultures showed that these lectins mostly stimulated CD4+ T lymphocytes. These results suggest that these lectins from different Artocarpus species are similar in terms of their mitogenic activity although their structural features are not identical.

Systemic and secretory humoral immunity in the normal human vaginal tract

The molecular status of Abs in the vaginal fluid is reconsidered as a basis for immunization strategies for women' vaccination against HIV. Analysis of separated immunoglobulins (Igs) shows a large proportion of uncleaved IgG, whereas the low amount of IgA includes SIgA, monomers and fragments. SIgM is at a very low level, while free SC molecules are abundant. In addition to the already documented local synthesis, vaginal IgG contains serum-derived tetanus antitoxins. The IgG could reach the lumen by diffusion, and/or be transported by an Fc receptor-associated mechanism as suggested by the subclass imbalance in favour of the IgG1 isotype. VAginal SIgA contains very low levels of antibodies o the cell-well carbohydrates from a dental caries-associated streptococcus confirming the participation of the secretory immune system. IN addition, the low percentage of IgA2 suggests tha a proportion of vaginal SIgA can also derive from actively transported serum polymers. In agreement with our previous studies showing induction of vaginal tetanus antitoxins by intramuscular immunization, these results are in favour of classical, parenteral vaccinations to induce protection of the human vagina.

Proliferative response of human CD4+ T lymphocytes stimulated by the lectin jacalin

The Gal beta(1-3)GalNAc-binding lectin jacalin is known to specifically induce the proliferation of human CD4+ T lymphocytes in the presence of autologous monocytes and to interact with the CD4 molecule and block HIV-1 infection of CD4+ cells. We further show that jacalin-induced proliferation is characterized by an unusual pattern of T cell activation and cytokine production by human peripheral blood mononuclear cells (PBMC). A cognate interaction between T cells and monocytes was critical for jacalin-induced proliferation, and human recombinant interleukin (IL)-1 and IL-6 did not replace the co-stimulatory activity of monocytes. Blocking studies using monoclonal antibodies (mAb) point out the possible importance of two molecular pathways of interaction, the CD2/LFA-3 and LFA-1/ICAM-1 pathways. One out of two anti-CD4 mAb abolished jacalin responsiveness. Jacalin induced interferon-gamma and high IL-6 secretion, mostly by monocytes, and no detectable IL-2 synthesis or secretion by PBMC. In contrast, jacalin-stimulated Jurkat T cells secreted IL-2. CD3- Jurkat cell variants failed to secrete IL-2, suggesting the involvement of the T cell receptor/CD3 complex pathway in jacalin signaling. IL-2 secretion by CD4- Jurkat variant cells was delayed and lowered. In addition to CD4, jacalin interacts with the CD5 molecule. Jacalin-CD4 interaction and the proliferation of PBMC, as well as IL-2 secretion by Jurkat cells were inhibited by specific jacalin-competitive sugars.

Proliferative response of B chronic lymphocytic leukemia lymphocytes stimulated with IL2 and soluble CD23

The in vitro proliferative response of purified B-chronic lymphocytic leukemia (B-CLL) lymphocytes cultured in the presence of soluble CD23 (sCD23) with or without IL2 was compared to the responses induced by phorbol 12-myristate 13-acetate (PMA), Staphylococcus aureus strain Cowan I (SAC), IL1, IL2, IL4, IL6 and the combination of IL2 and interferon (IFN) alpha or IFN gamma. As expected, B-CLL lymphocytes proliferated with PMA, SAC and IL2 with a clear enhancement of the IL2-induced response by IFN alpha or IFN gamma. They failed to proliferate in response to sCD23, IL1, IL4 or IL6 alone nor to the combinations of sCD23 and any of the 3 latter cytokines. However, sCD23 significantly increased the proliferation of B-CLL cells induced by IL2, suggesting a protective effect of sCD23 on apoptosis. Serum levels of sCD23 and CD23 membrane expression were high in every patient which is compatible with the hypothesis of an autocrine or paracrine activation loop. Detectable CD23 expression was lost in all cultures except for that stimulated by PMA. Only supernatants of PMA-stimulated cultures contained high sCD23 levels.

Isotypes of human vaccinal antibodies to the Vi capsular polysaccharide of Salmonella typhi

The immunoglobulin class and IgG subclass distribution of anti-Vi antibodies elicited by vaccination with a single injection of the purified polysaccharide or three injections of the inactivated whole cell typhoid vaccine was examined using an immunoenzymatic assay. The two vaccines induced antibody responses of similar magnitude and the predominant subclass of IgG antibodies was IgG1.

Characterization of the serum antibody response induced by Haemophilus influenzae type b tetanus protein-conjugate vaccine in infants receiving a DTP-combined vaccine from 2 months of age

The serum antibody response induced by Haemophilus influenzae type b capsular polysaccharide (CPS)-tetanus protein conjugate vaccine combined to DTP vaccine was characterized in infants receiving three injections from 2 months of age. Sixty-five per cent and 94% of infants had anti-CPS antibody levels > or = 1 micrograms ml-1 after the second and third dose, respectively. The antibody response was mostly made up of IgG with a marked IgG1 predominance. Significant rises in bactericidal and in complement-mediated opsonic activities were observed after immunization. These data clearly show that this vaccine can be successfully administered in one syringe together with DTP vaccine during the regular infant immunization programme.

Immunogenicity of Haemophilus influenzae type b conjugate vaccine in allogeneic bone marrow recipients

A randomized study was conducted in 40 allogeneic marrow recipients to compare the immunogenicity of two Haemophilus influenzae type b (Hib) vaccines (either the Hib capsular polysaccharide [Hib-CPS] or tetanus toxoid-conjugated Hib-CPS [Hib-CPS-T]). A second injection consisted of Hib-CPS-T. Before immunization, 3 patients had serum antibody levels > 1 microgram/mL. After the first injection, the response was better after Hib-CPS-T than after Hib-CPS but lower than in normal subjects; a number of patients lacked any IgG antibody response, especially after Hib-CPS. Of patients who received two injections of Hib-CPS-T, 85% achieved an antibody concentration > or = 1 microgram/mL. Hib-CPS-T induced a response in IgG2-deficient patients whereas Hib-CPS alone did not. IgG antibodies predominantly belonged to the IgG1 subclass. The antibody response was better in patients immunized late after graft. This study shows that Hib-CPS-T is more immunogenic than Hib-CPS in marrow recipients.

Immunogenicity of Haemophilus influenzae type b capsular polysaccharide and its tetanus toxoid conjugate in patients with recurrent infections or humoral immunodeficiency

The antibody response to the capsular polysaccharide of Haemophilus influenzae type b was evaluated after vaccination with the capsular polysaccharide or its tetanus toxoid conjugate in 41 randomized patients with recurrent infections, IgA deficiency, common variable immunodeficiency, or the Wiskott-Aldrich syndrome. Serum antibodies were measured using a Farr assay for total antibodies and an enzyme-linked immunosorbent assay for antibodies of the three main immunoglobulin classes and of each IgG subclass. Antibody levels reached concentrations generally considered as protective in the majority of cases, the best response being observed after two injections of the conjugate vaccine with a 1-month interval. Vaccination with the conjugate therefore seems to be promising for the prevention of Haemophilus influenzae type b infections in such patients.