CSF bicarbonate regulation in respiratory acidosis and alkalosis.

CSF bicarbonate regulation was studied in respiratory acidosis and alkalosis of 4h duration in antsthetized dogs. PCO2, pH, HCO3, ammonia, and lactate in CSF and arterial and safittal sinus bloof were measured when equal volumes of saline or acetazolamide (8 mg) were injected into lateral cerebral ventricles. The brain CO2 dissociation curve was determined at the end of all experiments. CSF and arterial bicarbonate increased 11.8 and 5.9 meg/l, respectively, in acidosis. Acetazolamide limited the rise in CSF bicarbonate to 4.2 meg/l, and prevented the CSF bicarbonate increase associated with hyperammonemia. During alkalosis CSF bicarbonate fell 6.5 meg/l and CSF lactate increased almost 2 meg/l while arterial bicarbonate fell 5.7 meg/l and lactate remained unchanged. Thus plasma bicarbonate changes account for some of the CSF unchanged. Thus plasma bicarbonate changes account for some of the CSF bicarbonate alterations in respiratory acid-base-disturbances. In acidosis additional CSF bicarbonate is formed by the choroid plexus and glial cells on the inner and outer surfaces of the brain--a reaction catalyzed by the locally present carbonic anhydrase. In alkalosis the greater fall in CSF bicarbonate than blood is due to selective brain and CSF lactic acidosis.     

An assay for colony-stimulating factor (CSF) production by single T lymphocytes: estimation of the frequency of cells producing granulocyte-macrophage CSF and multi-lineage CSF within a T lymphocyte clone

The frequency of cells producing hemopoietic colony-stimulating factors (CSF) in a murine T lymphocyte clone has been determined by using a simple microassay that does not require clonal expansion or the addition of accessory cells. When stimulated with concanavalin A (Con A), the clone LB3 produced both granulocyte-macrophage CSF (GM-CSF) and multi-lineage CSF (Multi-CSF), which could be detected by using the cell line FDC-P1, whose proliferation is dependent on the presence of either of these factors. Limiting dilution analysis of Con A-stimulated LB3 cells indicated a requirement for cell-cell contact for optimal production of CSF, which could be bypassed by preincubation of the cells at high density with Con A for 4 hr before dilution in the assay. Limiting dilution estimates of the frequency of CSF-producing cells among Con A-pretreated LB3 cells ranged from 20 to 50%. Direct measurement of CSF production by single Con A-pretreated cells isolated by micromanipulation revealed that 10 to 20% could secrete detectable CSF. However, when isolated Con A-pretreated two-cell and three-cell aggregates were assayed, 50 to 99% were positive, indicating that 30 to 80% of the cells in the aggregates secreted CSF. Assay of the supernatants from single cells and two-cell aggregates on both FDC-P1 cells and another cell line, 32D c13, which responds only to Multi-CSF, demonstrated that many cells produced GM-CSF only, and others varied in the relative quantities of GM-CSF and Multi-CSF produced.     

DIDS decreases CSF HCO3- and increases breathing in response to CO2 in awake rabbits

An inhibitor of the HCO3-/Cl- exchange carrier protein, 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) or vehicle was infused in mock cerebrospinal fluid (CSF) via the cisterna magna in conscious rabbits at 10 mumol/l for 40 min at 10 microliter/min. Neither treatment had any effect over 2-5 h on the non-CO2-stimulated CSF ion values or blood gases. With CO2 stimulation such that arterial PCO2 (PaCO2) was increased 25 Torr over 3 h, DIDS treatment significantly decreased the stoichiometrically opposite changes in CSF [HCO3-] and [Cl-] that normally accompany hypercapnia and reflect ionic mechanisms of CSF pH regulation. Expressed as delta CSF [HCO3-]/delta PaCO2, DIDS treatment decreased the CSF ionic response by 35%. In a separate paired study design DIDS administration via the same protocol had no effect on resting ventilation but significantly increased the ventilation and tidal volume responses to a 28-Torr increase in PaCO2. Expressed as change in minute ventilation divided by delta PaCO2, DIDS treatment produced a 39.6% increase. The results support the concept of a DIDS-inhibitable anion exchange carrier being involved in CSF pH regulation in hypercapnia and suggest a DIDS-related effect on the ventilatory response to CO2.     

Antibodies to colony-stimulating factors block Lewis lung carcinoma cell stimulation of immune-suppressive bone marrow cells

Summary Progressive growth of metastatic Lewis lung carcinoma (LLC) tumors results in a concurrent stimulation of myelopoiesis and the appearance of immune-suppressive bone marrow cells. The present study has shown that normal bone marrow cells could be induced to become immune-suppressive by 3 days of culture with supernatants of cloned metastatic LLC-LN7 variant cells. The capacity of the LLC-LN7 supernatants to stimulate the appearance of suppressor cells was directly proportional to the concentration of supernatant used in the bone marrow culture. When adoptively transferred with a LLC-LN7 tumor inoculum, the supernatant-induced suppressor bone marrow cells increased the rate of appearance of palpable tumors and the frequency of tumor establishment. The LLC-LN7 supernatants containing suppressor-cell-inducing activity also had colony-stimulating factor (CSF) activity. The CSF activity produced by the LLC-LN7 cells could be diminished with neutralizing antibodies to either granulocyte/monocyte(GM-) CSF or to interleukin-3 (IL-3). Likewise, the suppressor-inducing activity in the LLC-LN7 supernatants was diminished by pretreatment with anti-GM-CSF or anti-IL-3. The combination of anti-GM-CSF and anti-IL-3 completely neutralized all suppressor-inducing activity produced by the LLC-LN7 cells. These results suggest that the secretion of IL-3 and GM-CSF by LLC-LN7 tumor cells is a mechanism by which the tumors stimulate myelopoiesis and induce normal bone marrow cells to become immune-suppressive. Bone marrow cells that are induced to become immune-suppressive by culture with LLC-LN7 supernatants can, in turn, facilitate the establishment of tumor in vivo.This study was supported by the Medical Research Services of the Veterans Administration and by grant CA-45080 from the National Institutes of Health     

Effects of SITS, an anion transport blocker, on CSF ionic composition in metabolic alkalosis

Disulfonic stilbenes combine with the carrier protein involved in anion transport and inhibit the exchange of Cl- for HCO3- in a variety of biomembranes. Our aim was to determine whether such a mechanism is operative in the regulation of cerebrospinal fluid (CSF) [HCO3-] in metabolic alkalosis. In anesthetized, curarized, and artificially ventilated dogs either mock CSF (group I, 9 dogs) or mock CSF containing SITS, 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid (group II, 7 dogs) was periodically injected into both lateral cerebral ventricles. During 6 h of isocapnic metabolic alkalosis, produced by intravenous infusion of Na2CO3 solution, plasma [HCO3-] was increased by approximately 14 meq/l in both groups. In SITS-treated animals the mean cisternal CSF [HCO3-] increased by 7.7 meq/l after 6 h, and this was significantly higher than the respective increment, 3.5 meq/l, noted in the control group. Increments in CSF [HCO3-] in both groups were reciprocated by decrements in CSF [Cl-] with CSF [Na+] remaining unchanged. Cisternal CSF PCO2 and lactate concentrations showed similar increments in both groups. It is hypothesized that in metabolic alkalosis a carrier transports HCO3- out of cerebral fluid in exchange for Cl- and that SITS inhibits this mechanism. The efflux of HCO3- out of CSF in metabolic alkalosis would minimize the rise in CSF [HCO3-] brought about by HCO3-] influx from blood into CSF and therefore contributes to the CSF [H+] homeostasis.     

Piglets produced from cloned blastocysts cultured in vitro with GM‐CSF

In general, pig embryos established by somatic cell nuclear transfer (SCNT) are transferred at the one‐cell stage because of suboptimal embryo culture conditions. Improvements in embryo culture can increase the practical application of late embryo transfer. The goal of this study was to evaluate embryos cultured with granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) in vitro, and to track the in vivo developmental competency of SCNT‐derived blastocysts from these GM‐CSF embryos. The receptor for GM‐CSF was up‐regulated in in vitro‐produced embryos when compared to in vivo‐produced cohorts, but the level decreased when GM‐CSF was present. In vitro fertilized (IVF) embryos, supplemented with GM‐CSF (2 or 10 ng/ml), showed a higher frequency of development to the blastocyst stage compared to controls. The total cell numbers of the blastocysts also increased with supplementation of GM‐CSF. Molecular analysis demonstrates that IVF‐derived blastocysts cultured with GM‐CSF exhibit less apoptotic activity. Similarly, an increase in development to the blastocyst stage and an increase in the average total‐cell number in the blastocysts were observed when SCNT‐derived embryos were cultured with either concentration of GM‐CSF (2 or 10 ng/ml). When SCNT‐derived embryos, cultured with 10 ng/ml GM‐CSF, were transferred into six surrogates at Day 6, five of the surrogates became pregnant and delivered healthy piglets. Our findings suggest that supplementation of GM‐CSF can provide better culture conditions for IVF‐ and SCNT‐derived embryos, and pig SCNT‐derived embryos cultured with GM‐CSF in vitro can successfully produce piglets when transferred into surrogates at the blastocyst stage. Thus, it may be practical to begin performing SCNT‐derived embryo transfer at the blastocyst stage. Mol. Reprod. Dev. © 2013 Wiley Periodicals, Inc.     

Dynamics of cytokine production during coccidial infections in chickens: colony-stimulating factors and interferon

Abstract We assayed two classes of immunoregulatory cytokines, colony-stimulating factors (CSF) and interferon (IFN), during and immediately after a primary coccidial infection in chickens. Coccidial infection induces significant alterations in serum colony-stimulating activity (CSA) and these alterations immediately precede the characteristic biphasic leukocytosis. CSA rose sharply during the first 24 h post-inoculation (PI), but returned to control levels by 48 h PL. At this time, we detected an increase in peripheral blood leukocytes which peaked at 96 h PI. A second phase of CSA increase began 96 h PI and peaked at 120–144 h PI which again preceded the second phase of leukocytosis. We also examined the production of IFN during the first 20 days PI. Splenic T cells from Eimeria maxima -infected chickens produced significantly less IFN on day 5 PI compared to T cells from the coccidia-free controls. By days 10 and 15 PI, there was no significant difference in IFN production between the T cells of infected and non-infected chickens. However, by day 20 PI, IFN production by the T cells of the infected birds produced significantly more IFN than the control T cells. The results of our studies indicated the differential production of two different cytokines by chickens during and following a primary coccidial infection. Based on these experiments, CSF may be some of the first cytokines produced during an E. maxima -infection, while IFN may be one of the later cytokines produced.     

The regulation of haemopoiesis in long-term bone marrow cultures: I. Role of L-cell CSF

The effects of L-cell conditioned medium which contains granulocyte/macrophage colony stimulating factor (CSF); of highly purified L-cell CSF; and the antiserum directed against L-cell CSF, have been investigated in long-term murine bone marrow cultures. Treatment of cultures with CSF containing conditioned medium led to a rapid decline in haemopoiesis. However, this inhibition of in vitro haemopoiesis is probably caused by materials other than CSF, since the addition of highly purified L-cell CSF had no appreciable effect upon long-term haemopoietic cell proliferation or differentiation. Furthermore, the inhibitory activity of L-cell conditioned medium was not abrogated following neutralization of the CSF activity by CSF antiserum. The direct addition of CSF antiserum did not inhibit granulocyte or macrophage formation. These results suggest that long-term cultures of murine marrow cells may show extensive interactions with stromal cells which are not influenced by exogenous stimulatory or inhibitory factors.     

Production of granulocyte colony-stimulating factor by head and neck carcinomas

Detectable levels of G-CSF by enzyme-linked immunosorbent assay (ELISA) were found in sera of 4 out of 15 patients with head and neck carcinomas. Also cells prepared from the tumors of these 4 patients secreted G-CSF. The supernatants of cells derived from all 15 patients did not contain granulocyte-monocyte CSF, monocyte CSF, tumor necrosis factor-, transforming growth factor- ₁, epidermal growth factor, interleukin (IL)-1 and IL-6. These findings suggest that leukocytosis in patients with carcinomas might be due to the production of G-CSF by tumor cells.Abbreviations CSF colony stimulating factor - EGF epidermal growth factor - ELISA Enzyme-linked immunosorbent assay - G granulocyte - GM granulocyte-monocyte - IL interluekin - M monocyte - TGF transforming growth factor - TNF tumor necrosis factor     

Effects of debrisoquin on CSF and plasma HVA concentrations in man

Data from animal studies indicate neuroleptic drugs act via their properties as antagonists of CNS dopamine (DA) receptors and this finding has led to the suggestion that alterations in CNS DA neuronal function are associated with psychotic disorders. Clinical investigations of this hypothesis, however, have been hindered by the lack of the availability of a direct and relatively easily obtained index of CNS DA neuronal activity. The work reported here was aimed at the development of such an index. Using a double blind design, human male subjects were given either placebo or debrisoquin, which is a monoamine oxidase inhibitor which does not penetrate brain. On the baseline day (no debrisoquin) and after 6 and 13 days of drug administration blood samples were obtained. In addition, for some patients CSF specimens were obtained via lumbar puncture on the baseline day and after 13 days of drug administration. It was found that debrisoquin produced a highly significant decrease in plasma homovanillic acid (HVA) concentrations whereas the concentrations of HVA in CSF were unchanged. In addition, it was found that the correlation between CSF and plasma HVA prior to debrisoquin was non-significant (r = 0.39, p = N.S., N = 10) whereas after 13 days of debrisoquin treatment the correlation was highly significant (r = 0.95, p less than .01, N = 7). These findings suggest that the administration of debrisoquin produces a situation in which plasma HVA reflects CNS HVA production, and as such debrisoquin may be a useful tool for the clinical investigator who is interested in studying relationships in human subjects between CNS DA neuronal system function and psychopathological states or other disorders which may be mediated via brain DA systems.     

高活性重组hG-CSF的制备

我们构建了新的硫氧还蛋白（Ｔｈｉｏｒｅｄｏｘｉｎ）融合表达载体ｐＥＴＴｒｘＬ和ｐＥＴＴｒｘ－ＨｉｓＬ,它们可使功能蛋白在大肠杆菌胞质中以可溶性形式高效表达。利用此表达系统成功地获得的ｈＧ－ＣＳＦ－硫氧还蛋白融合蛋白的高效可溶性表达,表达水平达总细胞可溶蛋白的４１％以上。所表达的ｈＧ－ＣＳＦ－硫氧还蛋白融合蛋白可通过Ｃｕ２＋－ＩＤＡＳｅｐｈａｒｏｓｅＦＦ固相金属螯合层析柱,方便地从细胞破碎可溶上清中直接纯化。所获得的融合蛋白具有ｈＧ－ＣＳＦ特异的生物活性,其比活性达到０．５－１．３３×１０７ｕ／ｍｇ融合蛋白。这样表达的ｈＧ－ＣＳＦ融合蛋白能被ＩｇＡ蛋白酶特异地切割,将ｈＧ－ＣＳＦ从融合蛋白上切下获得与天然蛋白一级结构完全一致的重组ｈＧ－ＣＳＦ 。     

Brain amine metabolism is reflected in cerebral ventricular CSF

The choroid plexuses are suspended within the ventricles and account for approximately 75% of CSF production. The sodium-potassium ATPase operates within the choroidal epithelial cells and moves sodium ions towards the ventricular surface and potassium ions in the direction of the stroma. Water flows into CSF along osmotic gradient produced by sodium pump. The existence of extracellular channels by which brain metabolites could passively diffuse into the ventriculosubarachnoid space suggests an excretory role for CSF. Removal of solutes from the CSF could occur across the choroidal epithelium or arachnoid membrane into the blood. Systematically administered monoamine metabolites do not cross the blood-brain or the blood-CSF barrier. The regional concentrations of amine metabolites in the CSF is in part a reflection of the concentration of catecholamines and indoleamines in the immediately adjacent neuronal parenchyma. In order to illustrate the validity of monoamine metabolite determinations in cerebral ventricular CSF we developed a device which allowed for a continuous third ventricular CSF withdrawal in freely moving (or anesthetized) rats at a constant flow of 1 microliter/min. The elevation of biogenic amine metabolites in CSF by probenecid or their decline by monoamine oxidase inhibition was used to assess the rate of turnover of amines. Pharmacological manipulations (yohimbine, haloperidol, ouabain) resulted in mono-amine metabolite fluctuations in CSF similar to those previously described in brain tissue. Insulin administration caused an abrupt decrease in CSF glucose and elevated dopamine and serotonin metabolites in rats which had no access to food. These studies demonstrate the adaptation of in vivo analysis of CSF in rats but also exemplify the usefulness of monoamine metabolite determination in the CSF as indicators of brain function.     

Comparison of in vitro and in vivo modulation of myelopoiesis by biological response modifiers

Summary In vitro growth and differentiation of granulocyte-macrophage progenitor cells (GM-CFU-C) requires colony-stimulating factors (CSF), and an in vivo role for CSF has also been proposed. Prostaglandins of the E series (PGE) have been reported to serve as negative feedback regulators of myelopoiesis. Here, we report evidence of augmented CSF secretion by mouse peritoneal Mo (macrophages) and bone marrow cells in vitro upon stimulation with various biological response modifiers (BRMs). Optimal induction of CSF secretion occurred after in vitro treatment of peritoneal Mo and mononuclear bone marrow cells with 50 g/ml poly ICLC (polyriboinosinic-polycytidylic acid poly-L-lysine), 5 g/ml lipopolysaccharide (LPS), or 500 U/ml interferon (IFN_,) for 2 days. The in vitro stimulation of CSF secretion was paralleled by an increase in PGE secretion by Mo and bone marrow cells. The PGE secretion could, however, be selectively blocked by preincubating the cells for 3 h with indomethacin (10^–7 Mol) leaving CFS production intact. In vivo treatment of mice with either maleic anhydride divinyl ether copolymer (MVE-2; 25 mg/kg) or poly ICLC (2 mg/kg) significantly increased levels of CSF in serum, as well as in culture supernatants of in vivo-treated peritoneal Mo and bone marrow cells. The increase in serum CSF levels and in secretion of CSF by peritoneal Mo and bone marrow cells was followed by a dose-dependent increase in GM-CFU-C, in nucleated bone marrow cells, and in peripheral blood leukocytes. The same BRMs also stimulated the secretion of PGE by in vivo-activated peritoneal Mo, but not by bone marrow cells. Pretreatment of the mice with indomethacin (4 mg/kg) almost completely suppressed PGE secretion by peritoneal Mo, but did not change the CSF secretion by peritoneal Mo or bone marrow cells and had no significant effect on bone marrow cellularity. Therefore, MVE-2 and poly ICLC, in addition to their immunomodulatory activity, can also have stimulatory effects on myelopoiesis, presumably mediated through secretion of CSFs. Protection and/or restoration of bone marrow function could thus either provide the opportunity for more extensive chemotherapy or could increase the number of Mo effector cells available for activation against tumor targets.     

Dkk-3 is elevated in CSF and plasma of Alzheimer's disease patients

Biomarkers in CSF can offer improved diagnostic accuracy for Alzheimer's disease (AD). The present study investigated whether the glycoprotein and putative tumor suppressor Dickkopf homolog 3 (Dkk-3) is secreted into CSF and evaluated its applicability as a diagnostic marker for AD. Using our highly specific immunoenzymometric assay, Dkk-3 levels were measured in plasma and/or CSF of patients suffering from depression, mild cognitive impairment (MCI), or AD and compared with healthy subjects. Dkk-3 identity was verified by western blot and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS)/MS. High concentrations of Dkk-3 were detected in CSF compared with plasma (28.2 ± 1.3 vs. 1.22 ± 0.04 nmol/L, respectively). Consistently Dkk-3 expression was demonstrated in neurons of the cortex and epithelial cells of the choroid plexus, the major source of CSF. Significantly increased Dkk-3 levels in plasma and CSF were observed for AD patients compared with healthy subjects but not patients suffering from MCI or depression. In summary, our data indicate that elevated Dkk-3 levels are specifically associated with AD and might serve as a potential non-invasive AD biomarker in plasma.     

Cerebrospinal Fluid (CSF) 25-Hydroxyvitamin D Concentration and CSF Acetylcholinesterase Activity Are Reduced in Patients with Alzheimer's Disease

Background

Little is known of vitamin D concentration in cerebrospinal fluid (CSF) in Alzheimer´s disease (AD) and its relation with CSF acetylcholinesterase (AChE) activity, a marker of cholinergic function.

Methods

A cross-sectional study of 52 consecutive patients under primary evaluation of cognitive impairment and 17 healthy controls. The patients had AD dementia or mild cognitive impairment (MCI) diagnosed with AD dementia upon follow-up (n = 28), other dementias (n = 12), and stable MCI (SMCI, n = 12). We determined serum and CSF concentrations of calcium, parathyroid hormone (PTH), 25-hydroxyvitamin D (25OHD), and CSF activities of AChE and butyrylcholinesterase (BuChE).

Findings

CSF 25OHD level was reduced in AD patients (P < 0.05), and CSF AChE activity was decreased both in patients with AD (P < 0.05) and other dementias (P < 0.01) compared to healthy controls. None of the measured variables differed between BuChE K-variant genotypes whereas the participants that were homozygous in terms of the apolipoprotein E (APOE) ε4 allele had decreased CSF AChE activity compared to subjects lacking the APOE ε4 allele (P = 0.01). In AD patients (n=28), CSF AChE activity correlated positively with CSF levels of total tau (T-tau) (r = 0.44, P < 0.05) and phosphorylated tau protein (P-tau) (r = 0.50, P < 0.01), but CSF activities of AChE or BuChE did not correlate with serum or CSF levels of 25OHD.

Conclusions

In this pilot study, both CSF 25OHD level and CSF AChE activity were reduced in AD patients. However, the lack of correlations between 25OHD levels and CSF activities of AChE or BuChE might suggest different mechanisms of action, which could have implications for treatment trials.     

Spinal CSF absorption in healthy individuals

The present study examines the extent of spinal cerebrospinal fluid (CSF) absorption in healthy individuals in relation to physical activity, CSF production, intracranial pressure (ICP), and spinal CSF movement. Thirty-four healthy individuals aged 21-35 yr were examined by lumbar puncture and radionuclide cisternography with repeated imaging. ICP was registered before and after CSF drainage, and CSF production was calculated. Spinal CSF absorption was calculated as reduction in spinal radionuclide activity. The radionuclide activity in the spinal subarachnoidal space was gradually decreased by 20 +/- 13% (mean +/- SD) during 1 h. The reduction was higher in active than in resting individuals (27 +/- 12% vs. 13 +/- 9%). The mean ICP in 19 of the individuals was 13.6 +/- 3.1 cm H(2)O. B-waves were found in 79% of the individuals, with a mean frequency of 0.6 +/- 0.3 min(-1). The mean CSF production rate was 0.34 +/- 0.13 ml/min. There were no correlations between radionuclide reduction, spinal movement of the radionuclide, and CSF production rate. The spinal radionuclide reduction found in this study indicates a spinal CSF absorption of 0.11-0.23 ml/min, more pronounced in active than in resting individuals.     

CSF distribution of morphine, methadone and sucrose after intrathecal injection

The lumbar to cisternal CSF distribution of morphine and methadone were compared to C-14 sucrose, a standard marker of CSF bulk flow, after lumbar subarachnoid injections in a sheep preparation. Morphine appeared and peaked simultaneously with C-14 sucrose in cisternal CSF at 90 to 190 minutes. The mean peak cisternal CSF morphine concentrations were sustained for 30-40 minutes, and averaged 148 ng/ml, representing 0.3% of the administered dose. Methadone was not detectable in cisternal CSF up to 240-300 minutes after lumbar subarachnoid administration. The C-14 sucrose/morphine ratio was increased an average of 6.7 times in cisternal CSF as compared to the ratio of the two compounds injected into the lumbar subarachnoid space. These studies demonstrate that morphine, a hydrophilic opioid, given intrathecally moves rostrally and appears in cisternal CSF by bulk flow. Furthermore the rostral redistribution of morphine is associated with the clearance of morphine from CSF. Methadone, a lipophilic opioid, appears to be completely cleared from CSF before it reaches the cisterna magna. These pharmacokinetic studies support a contribution of supraspinal sites to the analgesic and adverse effects produced by morphine given by spinal routes of administration. In contrast methadone appears to exert its effects predominantly at spinal sites.     

Characterization of mononuclear phagocytes in human CSF using membrane markers.

The purpose of this investigation was to demonstrate those membrane receptor sites on mononuclear phagocytes of human CSF which provide additional evidence for their monocytic origin and function. Using a heterologous system, sheep red blood cells were coated with IgG- and IgM-fraction of the anti-Forssman-antiserum of rabbits. In another series of experiments, sheep red blood cells were additionally sensitized with fresh human serum as a source of complement. The possible inhibitory effect of human IgG on the uptake of red cell antibody complexes was tested. Washed and pretreated sheep red cells were added to different fresh CSF specimens from patients, whose CSF exhibited no conspicious biochemical, serologic or cytologic alterations. The percentage of phagocytizing mononuclear phagocytes was evaluated. When the particular IgG EA reagent described was utilized, most of the mononuclear phagocytes consistently exhibited the IgG- and complement-receptor activity which selectively characterizes blood monocytes and related cells.     

Correlation of plasma and CSF prolactin with CSF GABA during neuroleptic treatment

We measured serum and CSF prolactin and CSF 5HIAA, HVA and GABA at two time points separated by an average period of 21 days during the beginning of neuroleptic treatment in 26 psychotic patients. Prolactin levels were higher in females at both time points, and there was little evidence of tolerance during the measurement period. The prolactin values showed considerable intercorrelation. CSF GABA tended to be negatively correlated with prolactin values, particularly in male subjects. There were few significant correlations between the prolactin measures and CSF metabolites or clinical ratings.     

T cell derived HIV-1 is present in the CSF in the face of suppressive antiretroviral therapy

HIV cerebrospinal fluid (CSF) escape, where HIV is suppressed in blood but detectable in CSF, occurs when HIV persists in the CNS despite antiretroviral therapy (ART). To determine the virus producing cell type and whether lowered CSF ART levels are responsible for CSF escape, we collected blood and CSF from 156 neurosymptomatic participants from Durban, South Africa. We observed that 28% of participants with an undetectable HIV blood viral load showed CSF escape. We detected host cell surface markers on the HIV envelope to determine the cellular source of HIV in participants on the first line regimen of efavirenz, emtricitabine, and tenofovir. We confirmed CD26 as a marker which could differentiate between T cells and macrophages and microglia, and quantified CD26 levels on the virion surface, comparing the result to virus from in vitro infected T cells or macrophages. The measured CD26 level was consistent with the presence of T cell produced virus. We found no significant differences in ART concentrations between CSF escape and fully suppressed individuals in CSF or blood, and did not observe a clear association with drug resistance mutations in CSF virus which would allow HIV to replicate. Hence, CSF HIV in the face of ART may at least partly originate in CD4+ T cell populations.