Surgical treatment of neuromuscular scoliosis: current techniques.

41 consecutive patients surgically treated at Our Department by posterior only instrumented fusion from January 1995 to January 2009 were reviewed. There were 20 females and 21 males with a mean age of 15.8 years (range, 10 to 38). Diagnosis was: cerebral palsy (13 cases), Duchenne muscular dystrophy (7), spinal amyotrophy (7), myelomeningocele (5), poliomyelitis (3), Friedreich's ataxia (2), Escobar syndrome (2), Steinert's disease (1), Charcot Marie Tooth disease (1). Main scoliosis Cobb angle averaged 94.05° (range, 34° to 165°), the curve was thoracic in 19 cases, thoracolumbar or lumbar in 22 cases. Kyphosis (T5-T12) averaged 42.86° (range, 7° to 90°), lordosis was 33.57°. The fusion was extended to the lumbar tract in 23 patients, to the sacrum in the other 18. Our results showed that, in patients with neuromuscular scoliosis, posterior instrumented fusion is a safe and effective procedure and is the treatment of choice for patients with limited respiratory function, as in Duchenne muscular dystrophy and spinal muscular atrophy. The surgery should be performed as early as possible, and the extension of the fusion to the sacrum should be avoided in patients with residual walking ability.

Surgical treatment for scoliosis associated with rare disease.

This is a retrospective study of 11 patients, 7 females and 4 males, treated at Our Department for an early onset scoliosis (EOS) associated with rare syndromes with growing spinal implants (Growing Rod or VEPTR-like) from 2006 to 2011. Mean follow-up was 24 months (range, 12 to 36). The mean age at surgery was 7. Patients were affected by Escobar's syndrome (1), scoliosis associated to congenital heart disease (1), Arnold Chiari type 1 (1), syringomyelia (1), NF 1 (2), Prader-Willi syndrome (1), trisomy 8 (1), arthrogryposis (2) and spondylo-rib dysplasia (1). Each patient was studied from the genetic point of view, and were performed: brain-spine MRI, pulmonary function tests, Cardio-US and abdominal US, neuropsychiatric and neurological evaluation, C0-C2 CT scan. After first implant and lengthening procedures (11), the correction of the thoracic curve averaged 50%. Unfortunately, a little loss of correction of the lumbar curve occurred during the follow up. There were 8 post-operative complications, that required revision surgery in 2 cases. Our results confirmed the effectiveness and safety of growing spinal implants in the treatment of early-onset scoliosis in rare syndromes.

Complications incidence in the treatment of early onset scoliosis with growing spinal implants.

Early onset scoliosis (EOS) surgery based on growing spinal implants can lead to several complications. Aim of the study was to identify strategies to prevent those complications. A retrospective review was conducted to identify all pediatric patients affected by EOS surgically treated with growing rod or Vertical Expandable Prosthetic Titanium Rib (VEPTR) at our division between 2006 and 2011. Nineteen consecutive patients (8 males, 11 females; mean age 6.8 years) were included. The scoliosis was: idiopathic in 7 cases, congenital in 5, associated with congenital heart disease in 2, with syringomyelia and Arnold Chiari syndrome in 1, with neurofibromatosis type 1 (NF1) in 1, with Prader Willi syndrome in 1, with trisomy 8 in 1, with arthrogryposis in 1. Instrumentation used was: growing rod in 9 patients (dual rod construct in 8 cases, single rod in 1), VEPTR in 10 (always rib to spine construct). At a mean follow-up of 28 months (range, 12 to 55) 12 mechanical complications occurred in 8 of 19 patients treated (42.1%). Among cases treated with growing rod (9) 6 complications occurred in 4 patients (44.4%): revision was performed in 4 cases due to proximal anchors migration, in 2 cases due to a rod breakage. Among cases treated with VEPTR (10) 6 complications occurred in 4 patients (40%): revision was performed in 4 cases due to rib fracture with anchors migration, in 1 case due to vertebral anchor migration and in 1 case due to proximal and distal anchor migration. So, in our series mechanical complications rate was 42.1%. Our strategy to prevent these complications is to use hooks as proximal anchors, to avoid single rod construct and to use a brace as external support until final surgery is performed. If it's possible, is better to substitute VEPTR with a dual Growing Rod implant when patient's age and anatomy permits this.

IgM monoclonal gammopathy-associated neuropathies with different IgM specificity.

BACKGROUND AND PURPOSE: Antibodies directed against myelin-associated glycoprotein (MAG) are believed to be the most frequent biologic marker of the neuropathies associated with IgM monoclonal gammopathy of undetermined significance (MGUS). The objective of this study was to examine the prevalence of antiganglioside and/or sulfatide-positive patients and their clinical findings, including therapeutic response, compared to anti-MAG-positive or seronegative patients. METHODS: We prospectively followed 46 patients with MGUS who were diagnosed in our tertiary referral centers for polyneuropathy since 1997. All patients underwent nerve conduction studies and were tested for anti-MAG, gangliosides, and sulfatide antibodies. All the anagraphic and clinical data (including symptoms, disability scale, therapy, secondary malignancy development) were recorded in a database and compared between three patients' groups (anti-MAG-positive; antiganglioside/sulfatide-positive; no reactivity). RESULTS: Anti-MAG reactivity was present in 17 (37%) patients; other 17 patients (37%) had antiganglioside/sulfatide reactivity and 12 (26%) had no reactivity. Patients with antiganglioside/sulfatide positivity, although heterogeneous by a clinical and neurophysiological point of view, had the most severe neuropathic manifestations and a higher disability score at nadir (P < 0.001). These patients had a better response to both intravenous immunoglobulin therapy and rituximab. CONCLUSIONS: Our results suggest that antiganglioside/sulfatide-positive patients form a relevant portion of patients with MGUS-associated polyneuropathy seen in tertiary care centers and should be considered in future studies on treatment response.

The prevention of neural complications in the surgical treatment of scoliosis: the role of the neurophysiological intraoperative monitoring.

Iatrogenic spinal cord injury is the most feared complication of scoliosis surgery. The importance of combined somatosensory evoked potentials (SEP) and motor evoked potentials (MEP) monitoring during spine surgery is well known. The current authors retrospectively evaluated the results of neurophysiological intraoperative monitoring (IOM) in a large population of patients who underwent surgical treatment for spinal deformity. Intraoperative monitoring of SEPs and transcranial electrical stimulation MEPs (TES-MEP) was performed in 172 successive patients who underwent surgical treatment of idiopathic (128 pts), congenital (15 pts) or syndromic (29 pts) scoliosis. The first 106 patients (Group 1) underwent only SEP monitoring, while the other 66 patients (Group 2) underwent combined SEP and TES-MEP monitoring, when the technique was introduced in the current authors' institution. Halogenate anaesthesia (Sevoflurane, MAC 0.6-1.2) was performed in Group 1 cases, total intravenous anaesthesia (Propofol infusion, 6-10 mg/kg/h) in Group 2 patients. A neurophysiological "alert" was defined as a reduction in amplitude (unilateral or bilateral) of at least 50% for SEPs and of 65% for TES-MEPs compared with baseline. In Group 1, two patients (1.9%) developed postoperative neurologic deficits following surgical correction of spinal deformity, consisting of permanent paraparesis in one case and transient paraparesis secondary to spinal cord ischaemia in the other. Twelve patients presented intraoperative significant changes of neurophysiological parameters that improved following corrective actions by surgeons and anaesthesiologists, and did not show any postoperative neurologic deficits. In ten cases the alert was apparently unrelated to surgical manoeuvres or to pharmacological interventions and no postoperative neurologic deficits were noted. Considering the patients of Group 2, two patients (3.0%) presented transient postoperative neurologic deficits preceded by significant intraoperative changes in SEPs and TES-MEPs. In five cases a transient reduction in the amplitudes of SEPs (1 patient) and/or TES-MEPs (5 patients) was recorded intraoperatively with no postoperative neurologic deficits. In conclusion, in the current series of 172 patients the overall prevalence of postoperative neurologic deficit was 2.3% (4 patients). When combined SEP and TES-MEP monitoring was performed, the sensitivity and specificity of IOM for sensory-motor impairment was 100 and 98%, respectively. Combined SEP and TES-MEP monitoring must be regarded as the neurophysiological standard for intraoperative detection of emerging spinal cord injury during corrective spinal deformity surgery. Early detection affords the surgical team an opportunity to perform rapid intervention to prevent injury progression or possibly to reverse impending neurologic sequelae.

Neuromuscular maturation in the neonate: Combined electroneurographic and ultrasonographic study.

BACKGROUND: The combined electroneurography and muscle ultrasound examination (ENG-USM) in adult patients showed a correlation between the compound motor action potential (CMAP) and muscular thicknesses (MT). No similar studies exist regarding the neonatal period. AIM: To evaluate the correlations between the maximum compound muscle action potential (CMAP) and maximum muscle thickness (MT) in term and premature newborns versus a group of young adults, as measured by combined electroneurography-ultrasonography (ENG-USM) to assess the stages. STUDY DESIGN: Observational cohort study. SUBJECTS: We studied 36 subjects (14 premature and 11 term infants, and 11 young adults), who underwent ENG-USM of the tibialis anterioris (TA) muscle. OUTCOME MEASURES: We measured: 1) Onset-Peak (O-P) and Peak-to-Peak (P-P) maximum CMAP; 2) maximum MT; and 3) MT at the detected maximum CMAP. RESULTS: The maximum CMAP in term newborns studied was about 1/3 of the mean value measured in the adults; the differences between O-P and P-P values of the term versus premature infants were not significant. We did not find a good correlation between maximum MT and maximum CMAP in the term (r = 0.63) newborns, contrary to what was found in preterms (r = 0.95) and in young adults (r = 0.98). CONCLUSION: Our ENG-USM study shows that in newborns, the site of innervation of the neuromuscular plaque does not correspond to MT since muscle growth is related to the period of development, and depends on the progression of the nerve terminal branches that go to innervate the same muscle.

Selective thoracic surgery in the Lenke type 1A: King III and King IV type curves.

Pedicle screw fixation enables enhanced three-dimensional correction of spinal deformities and effectively shortens the distal fusion level. However, the choice of distal fusion level is still controversial in single thoracic idiopathic scoliosis with the lumbar compensatory curve not crossing the middle line (Lenke type 1 with modifier A or King type III and IV curves).The authors retrospectively analyzed 31 patients treated by segmental pedicular instrumentation alone, affected by a single thoracic adolescent idiopathic scoliosis with a compensatory lumbar curve not crossing the midline (Lenke 1A), with an average age of 16.3 years (range 10-22 years). The patients with regard to the King classification were also assessed. A statistical analysis was performed to determine whether the two groups (King III, King IV) presented differences concerning the level of the stable vertebra (SV), end vertebra (EV), and neutral vertebra (NV) and were also analyzed the results at follow-up regarding the relationships between the SV, EV, and lowest instrumented vertebra (LIV). The statistical analysis showed a significant difference between the two curve types. In the King III type curve the SV, EV, and NV appeared to be more proximal than those of the King IV type curve and the segments between the SV, EV, and NV appeared to be reduced in King III curves compared with King IV curves. At a follow-up of 3.2 years (range 2.2-5) the thoracic curve showed a correction of 58.4% (from 62.3 degrees to 26.6 degrees ) and compensatory lumbar curve an average spontaneous correction of 52.4% (from 38.1 degrees to 18.1 degrees ).The position of the LIV was shorter than the position of the SV in 30 patients (97%) with an average "salvage" of 2.1 (from 1 to 4) distal fusion levels. Four cases (13%), all affected by a King IV type curve, presented at follow-up an unsatisfactory results due to an "adding on" phenomenon. The statistical analysis confirmed that this phenomenon was correlated with The King IV curve (P = 0.043; Chi-square test) and that the only predictive parameter for its onset was the LIV-SV difference (odds ratio = 0.093; with a confidence interval of 0.008-1): every time that in King IV curve type the LIV was three or more levels shorter than the stable vertebra at follow-up the "adding on" phenomenon was present. The authors conclude that Lenke's type 1 with modifier A includes two kinds of curves, King III and King IV and that the Lenke's type 2 curves and King V with the lumbar curve not crossing the middle line have a similar behavior. Therefore, it is of authors' opinion that "the adding on phenomenon" could be prevented by more rigidly defining K. IV versus K. III curves. In Lenke's 1/2 A-K. IV/V type with the rotation of the first vertebra just below the thoracic lower EV in the same direction as the thoracic curve, and when SV and EV show more than two levels of difference, it is necessary to extend the lower fusion down to L2 or L3 (not more than two levels shorter than the SV). Whereas in Lenke's 1/2 A-K. III/V with the rotation of the first proximal vertebra of lumbar curve in the opposite direction to the thoracic apex and when SV and EV show not more than two level gap differences, the position of the lowest instrumented vertebra can be two or three levels shorter than the stable vertebra with satisfactory postoperative spinal balance. Therefore, the stable vertebra and the rotation of lumbar curve are considered to be a reliable guide for selecting the lower level of fusion.

Thoracoplasty in the surgical treatment of adolescent idiopathic scoliosis.

A consecutive series of 40 adolescents surgically treated between 1998-2001, by posterior spinal fusion and thoracoplasty were compared with a similar group of 40 adolescents treated in the same period by posterior only segmental fusion. Clinical and radiographic analysis was performed, including the SRS-30 questionnaire and Pulmonary Function Tests (PFT). Minimum five years follow-up was requested. No statistical differences were found between the two groups in PFT's both pre-operatively and at latest follow up. Our findings suggest that thoracoplasty did not adversely affected long-term PFT's in AIS patients treated by posterior spinal fusion alone.

An innovative diagnostic procedure of vertebral deformities without exposure to X-rays.

The objective of the study was to compare standard manual X-ray measurements of vertebral deformities and values obtained from the Ortelius 800. 52 Patients (41 females and 11 males: mean age 20.35 years) with adolescent vertebral deformities, was studied. The patients were evaluated with standard radiographic views and the Ortelius 800. The parameters considered for the comparison were the angles of scoliosis and kyphosis and the values of global axial deformity, shoulder asymmetry and pelvic tilt. We also evaluated the modification of pelvic/shoulder angle after surgery (this parameter allows to evaluate vertebral rotation and can be derived only from the Ortelius 800). This study allowed us to conclude that there is a perfect agreement between measurements with the Ortelius 800 and those resulting from standard x-rays. The system has also proved to have the capability of quantifying changes in vertebral rotation.

Brainstem neurodegeneration correlates with clinical dysfunction in SCA1 but not in SCA2. A quantitative volumetric, diffusion and proton spectroscopy MR study.

Magnetic resonance (MR) techniques enable in vivo measurement of the atrophy of the brainstem and cerebellum in spinocerebellar ataxia type 1 (SCA1) and 2 (SCA2) patients, which is accompanied by a decrease in the concentration of N-acetyl aspartate (NAA) or of the NAA/creatine ratio in the pons and cerebellum. Mean diffusivity (D) is emerging as an additional sensitive and quantitative MR parameter to investigate brain diseases. In order to explore differences between the MR features of SCA1 and SCA2 and correlate the MR and clinical findings in the two conditions, we examined 16 SCA1 patients, 12 SCA2 patients and 20 healthy control subjects. The MR protocol included T1-weighted 3D gradient echo sequences, single-voxel proton spectroscopy of the right cerebellar hemisphere (dentate and peridentate region) and of the pons with a PRESS sequence and an external reference quantitation method, and (in nine patients with SCA1 and nine patients with SCA2) diffusion-weighted echo-planar images with reconstruction of the D maps. The patients were evaluated with the Inherited Ataxia Clinical Rating Scale (IACRS). Compared with control subjects, the SCA1 and SCA2 patients showed a decrease (P < 0.01) in the volume of the brainstem and cerebellum and in the concentration of NAA in the pons and cerebellar hemisphere, whereas D of the brainstem and cerebellum was increased. No significant difference was observed between the SCA1 and SCA2 patient groups. No correlation between cerebellar volume and dentate and peridentate NAA concentration was found in SCA1 or SCA2 patients. The volume of the brainstem, D of the brainstem and cerebellum and the concentration of NAA in the pons were correlated (P < 0.05) with the IACRS score in SCA1 but not in SCA2. This discrepancy is in line with the clinical observation that the clinical deficit has a later onset and faster progression in SCA1 and an earlier onset and slower progression in SCA2, and suggests that neurodegeneration of the brainstem is a comparatively more rapid process in SCA1. In conclusion, our study indicates that SCA1 and SCA2 substantially exhibit the same MR features. The correlation in SCA1 between clinical severity and quantitative volumetric, diffusion MRI and proton MR spectroscopy findings in the brainstem indicates that these measurements might be employed for longitudinal studies and hopefully as surrogate markers in future pharmacological trials of this condition.

Grafting after sinus lift with anorganic bovine bone alone compared with 50:50 anorganic bovine bone and autologous bone: results of a pilot randomised trial at one year.

Our aim was to compare the outcome of implants inserted in maxillary sinuses augmented with anorganic bovine bone grafts compared with those augmented with mixed 50:50 bovine and autologous bone grafts. Twenty sinuses with 1-4mm of residual crestal height below the maxillary sinuses were randomised into two groups according to a parallel group design (n=10 in each). Sinuses were grafted using a lateral approach. In one group the grafts were 50:50 anorganic bovine bone and autologous bone and in the other anorganic bovine bone alone. After 7 months, 32 implants had been inserted. Outcome measures were survival of implants, complications, marginal changes in the height of the bone, and soft tissue variables (pocket probing depth and bleeding on probing). Probabilities of less than 0.05 were accepted as significant. No patient failed to complete the trial and no implant had failed at 1 year. There were some minor complications. After 12 months, the mean (SD) marginal bone loss (mm) was 1.06 (0.61) in the 50:50 group and 1.19 (0.53) in the anorganic bovine group. The mean (SD) values for pocket probing depth (mm) and bleeding on probing (score) were 2.49 (0.38) and 1.59 (0.82) in the 50:50 group and 2.31 (0.64) and 1.36 (0.87) in the anorganic bovine group (neither difference was significant). The present data are consistent with the hypothesis that the outcome of implants inserted in sinuses grafted with either material is comparable.

Synthetic peptides in the diagnosis of neurological diseases.

For several years peptides have been used to investigate many aspects of the molecular mechanisms supporting the etiopathogenesis of neurological diseases. Even if well-established and commercially-available assays for the diagnosis of neurological diseases, based on peptides, are presently not available, much research has been focused to the comprehension of the pathogenetic mechanisms of relevant neurological diseases, such as Multiple Sclerosis, Alzheimer's disease and prion diseases. Several peptides, which strongly contributed to increase in the progress, and in the understanding of the molecular mechanisms of these important diseases, have been selected as antigens to be proposed in possible alternative diagnostic methodologies. The authors focused their attention on the possible peptides to be used as diagnostics for these three characteristic neurological diseases. In fact, Multiple Sclerosis is an autoimmune disease in which peptides have been used for the characterization of both B and T immune response, while Alzheimer's disease and prion diseases can be cumulative regarded as "protein folding disorders" in which peptides can be used to identify the misfolded protein.

Transthyretin amyloidosis and superficial siderosis of the CNS.

OBJECTIVE: To describe a previously unreported clinical and radiologic presentation of hereditary transthyretin (TTR)-related amyloidosis. BACKGROUND: Unexplained cerebellar ataxia, pyramidal syndrome, and hearing loss are observed in some patients with TTR-related amyloidoses. METHODS: We performed clinical, radiologic, and pathologic examinations of three family members with TTR-related (Ala36Pro) amyloidosis. RESULTS: The patient was a 69-year-old woman with vitreal amyloid deposits, progressive sensorineural deafness, cerebellar ataxia, pyramidal syndrome, and recurrent transient neurologic symptoms. Cranial MRI showed symmetric thin rims of low signal intensity in T2- and T2*-weighted images in the cortex of the sylvian fissures, of the cerebellar hemispheres and vermis, and in the quadrigeminal plate consistent with superficial siderosis of the CNS. Her older daughter had vitreal amyloid deposits, acute Brown-Sequard syndrome at C4, acute sensorineural deafness, and recurrent transient neurologic symptoms. Cranial MRI at age 48 revealed a rim of low signal intensity in T2- and T2*-weighted images in the superior vermis folia and the right sylvian cortex. In addition, two small hemosiderin deposits were seen in the left parietal cortex. Lumbar puncture yielded colorless CSF with increased ferritin content and was followed by fourth ventricle hemorrhage. Cranial MRI 11 months later showed progression of brain hemosiderin deposits. The younger daughter had vitreal deposits, sensorimotor polyneuropathy, and acute sensorineural hearing but no evidence of siderosis on cranial MRI. She died at age 43 years of posterior fossa subarachnoid hemorrhage, and the neuropathologic examination showed amyloid deposition in the leptomeningeal spaces and vessels. CONCLUSION: Transthyretin-related amyloidosis may cause superficial siderosis of the CNS through subarachnoid bleeding related to meningovascular amyloid deposition.

Longitudinal evaluation of leukoaraiosis with whole brain ADC histograms.

FLAIR and diffusion-weighted MRI were obtained twice (mean interval 20 +/- 4 months) in 10 patients with leukoaraiosis. At follow-up, visual extension of leukoaraiosis was unchanged, whereas the median of whole brain apparent diffusion coefficient (WB-ADC) histogram was increased (p= 0.008) and brain volume index (BVI) was decreased (p = 0.006). WB-ADC histogram and BVI are sensitive to leukoaraiosis and might be considered for monitoring progression of the disease.

Brainstem involvement in Unverricht-Lundborg disease (EPM1): An MRI and (1)H MRS study.

MRI of the brain and proton MRS ((1)H MRS) of the pons and dentate were obtained in 10 patients with genetically confirmed Unverricht-Lundborg disease (EPM1) and 20 control subjects. Patients with EPM1 showed (p < or = 0.01) loss of bulk of the basis pontis, medulla, and cerebellar hemispheres. Cerebral atrophy was present in six patients. The N-acetylaspartate/creatine and choline/creatine ratios were reduced in the pons but not in the dentate (p < or = 0.005). Brainstem involvement could play a role in pathophysiology of EPM1.

Antibodies specific for the lipid-bound form of myelin basic protein during experimental autoimmune encephalomyelitis.

On the hypothesis that myelin basic protein isolated with surrounding lipids may constitute an autoantigen in demyelinating diseases, we studied the antibody response to the lipid-free and lipid-bound form of myelin basic protein during the course of experimental autoimmune encephalomyelitis induced in rats with either form of protein. Immunization with the lipid-bound form of myelin basic protein induced high titres of antibodies directed to the protein, accompanied by no antibodies to cerebroside 30 days after immunization. Antibodies specifically directed to the lipid-bound form of myelin basic protein were revealed after removal of antibodies recognizing the delipidated myelin basic protein. Anti lipid-bound myelin basic protein antibodies could already be detected at day 10 post-immunization, reaching a maximum at day 20 post-immunization. Demonstrations of antibodies entirely specific for the lipid-bound form of myelin basic protein suggests that this molecule may present epitopes not to be found in its already extensively studied primary structure, possibly the result of conformational changes following lipid binding.

Pixantrone (BBR2778) reduces the severity of experimental allergic encephalomyelitis.

Pixantrone is less cardiotoxic and is similarly effective to mitoxantrone (MTX) as an antineoplastic drug. In our study, pixantrone reduced the severity of acute and decreased the relapse rate of chronic relapsing experimental allergic encephalomyelitis (EAE) in rats. A marked and long-lasting decrease in CD3+, CD4+, CD8+ and CD45RA+ blood cells and reduced anti-MBP titers were observed with both pixantrone and MTX. In vitro mitogen- and antigen-induced T-cell proliferation tests of human and rodents cells evidenced that pixantrone was effective at concentrations which can be effectively obtained after i.v. administration in humans. Cardiotoxicity was present only in MTX-treated rats. The effectiveness and the favorable safety profile makes pixantrone a most promising immunosuppressant agent for clinical use in multiple sclerosis (MS).

HIV antigen-reactive T cells detected by antigen-induced interferon gamma secretion.

The T cell repertoire to human immunodeficiency virus (HIV) was studied in HIV-infected patients of different clinical stages by the detection and enumeration of cells that secreted interferon gamma (IFN-gamma) in short-term cultures of blood mononuclear cells after stimulation in vitro with the HIV recombinant antigens pB1, p121, p24-15, gp160bac, and the HIV V3 loop peptide. T cell reactivities to cytomegalovirus (CMV) and Mycobacterium tuberculosis-purified protein derivative (PPD) were examined in parallel. Among 29 patients with HIV infection, 48% had blood cells recognizing one or more of the five HIV antigens. The mean numbers of HIV antigen-reactive T cells varied between 1/approximately 6000 blood cells for pB1 and 1/approximately 20,000 cells for p24-15. None of the five HIV antigens studied was identified as an immunodominant T cell epitope in HIV infection. T cells from 20% of the patients responded to all five HIV antigens in parallel, but the antigen preferentially recognized varied from patient to patient. Those with more advanced disease had a tendency to lower numbers of HIV antigen-reactive T cells. Most HIV-infected patients had both CMV- and PPD-reactive T cells, but numbers were significantly lower in more advanced disease. It should be possible to adopt the present method to evaluate fine specificities of the T cell repertoire to other antigens and to study the involvement of other cytokines besides IFN-gamma, for example, the Th2 cell-related cytokine interleukin 4.

Purification of bovine P2 myelin protein with bound lipids.

The P2 protein is a neuritogenic, small basic protein present in PNS myelin. It belongs to the family of the cytoplasmic lipid-binding proteins and can be incorporated in lipidic bilayers. P2 has been purified and crystallized only in the lipid-free form. Here we show that the P2 protein can be purified with bound lipids by applying to PNS myelin the same procedure that as used to purify lipid-bound myelin basic protein from CNS myelin. SDS-PAGE showed a single band of 16.5 kDa, and TLC showed the presence of most of the myelin lipids associated with the protein. Lipid-bound P2 revealed different circular dichroism spectra from the corresponding lipid-free form, indicating that lipids influence P2 conformation.

T and B cell responses to cytomegalovirus antigens in healthy blood donors and bone marrow transplant recipients.

We measured the production of interferon-gamma (IFN-gamma) from single T cells and the T cell proliferative response to different cytomegalovirus (CMV) antigens in healthy blood donors and bone marrow transplant recipients. The antigens consisted of a CMV nuclear antigen (CMV na) containing the pp65-kDa matrix protein and the immediate early antigens but lacking CMV glycoproteins, and an antigen comprising native CMV glycoproteins (CMV gp). We also measured the IgG antibodies to CMV na and CMV gp. The T cells reacted to CMV na in CMV seropositive blood donors both with the production of IFN-gamma and with proliferation, while bone marrow transplant recipients had a deficient T cell response. After stimulation with CMV gp, no T cell response could be observed in CMV seropositive subjects. IgG antibodies to CMV na coexisted in plasma with similar levels of antibodies to CMV gp.