NSW Cannabis Medicines Advisory Service preliminary survey results - Enquirer perceptions and patient outcomes

Background

In 2018, an innovative, State government‐funded cannabis medicines drug information service was established for health professionals in New South Wales (NSW). The NSW Cannabis Medicines Advisory Service (CMAS) provides expert clinical guidance and support to medical practitioners considering prescribing a cannabis medicine to their patient(s).

Aims

This research examines quality assurance and patient outcomes related to enquirers' experience with NSW CMAS.

Methods

Data collection involved an online, anonymous survey with two components. Following a health professional enquiry, quality assurance data were collected about the enquirers' experience with NSW CMAS. The second survey focussed on patient outcomes and provides real‐world observational data about cannabis medicines safety and effectiveness across a wide range of indications.

Results

Data collection occurred between January 2020 and June 2021. Preliminary analyses were based on 68 quality assurance and 50 patient outcomes survey responses. General practitioners represented the highest proportion of survey responses (n = 33; 49%). The most common enquiry involved ‘patient‐specific advice’ (n = 50; 74%). Patient‐specific information provided by the service was mainly used for prescribing decision support (n = 45; 90%).

Conclusions

Preliminary findings highlight the impact of an innovative cannabis medicines drug information service in supporting health professional clinical practice in an area of rapid knowledge translation. Quality assurance data indicate that the service is perceived well by the majority of enquirers. Patient outcomes data across a wide range of indications suggest some effectiveness and a reasonable safety profile for prescribed cannabis medicines for most patients.

Feasibility of face-to-face and online learning methods to provide nutrition education to midwives, general practice nurses and student nurses

Midwives and general practice nurses are ideally positioned to provide nutrition education to pregnant women. However, it appears that they do not receive sufficient nutrition training to enable them to fulfil this role. This study aimed to develop, implement and evaluate a suite of learning resources developed specifically for midwives, general practice nurses and student nurses. A four-module suite of learning resources was developed based on recommendations in the Australian Antenatal Care Clinical Guidelines as well as formative evaluation with stakeholders. The feasibility of these modules was tested using a pre-test and post-test quasi-experimental design with three arms using convenient sampling (face-to-face with midwives; online with student nurses; and online with midwives, nurses and practice nurses). Completion rates across the three study arms were poor (n=40 participants in total). For the combined data, there was a significant increase in knowledge scores across all modules from the pretest score (median (IQR): 3.46 (2.09–4.13)) to the post-test score (5.66 (4.66–6.00)) (p<0.001). Studies of high quality are required to determine if changing the nutrition knowledge and confidence in delivering nutrition care of health professionals results in sustainable changes to their clinical practice.

IFN-beta modulates specific T cell responses in vitro but does not affect Experimental Autoimmune Encephalomyelitis in the SJL mouse

In this study, mouse recombinant IFN-beta was shown to favor PLP139-151-specific Th2 responses in vitro, by inhibiting IFN-gamma production and stimulating IL-4 and IL-10 production. IFN-beta (5000 U/day) failed to prevent the development or severity of EAE induced with PLP139-151. Whereas efficacy of IL-10 was found in the B. pertussis assisted but not in the pertussigen-assisted EAE model, both models appeared insensitive to IFN-beta. Also the combination of (suboptimal) IL-10 and IFN-beta appeared ineffective in inhibiting disease. However, the PLP139-151-specific IL-10 production by T cells from these mice appeared significantly more sensitive to the stimulatory effect of IFN-beta in vitro. It is concluded that despite its Th2 promoting effects, IFN-beta is not effective in inhibiting EAE in this study.

Minor myelin proteins can be major targets for peripheral blood T cells from both multiple sclerosis patients and healthy subjects

T cell recognition of myelin is likely to play a role in the pathogenesis of multiple sclerosis. Predominant protein components of myelin, myelin basic protein (MBP) and proteolipid protein (PLP), have been considered as possibly relevant autoantigens, especially since both proteins are encephalitogenic in various laboratory animals. It has remained unclear, however, to what extent the numerous minor proteins contained in myelin may serve as targets for human T cell responses to myelin. In this study, the abilities of several minor myelin proteins to trigger proliferative responses of human peripheral blood T cells were compared to that of MBP. By using a water soluble collection of myelin proteins as an antigen, including MBP as the major component, short-term T cell lines were generated. Proliferative responses were determined against the various proteins after their fractionation by HPLC. Short-term T cell lines from both multiple sclerosis patients and healthy control subjects displayed significant responses to several minor myelin proteins but failed to respond to MBP. Only the use of purified MBP as trigger antigen allowed the selective expansion of MBP-specific T cell lines. These findings indicate that minor myelin proteins may act as relevant targets for autoreactive human T cells.

HLA class I and II molecules present influenza virus antigens with different kinetics

Human leukocyte antigen (HLA) class I and class II molecules differ with respect to their intracellular pathways and the compartments where they associate with processed antigen. To study possible consequences of these differences for the kinetics of antigen presentation by HLA class I and class II molecules, we analyzed changes in the concentrations of free intracellular calcium ions in influenza virus-specific T cell clones after recognition of specific antigen/HLA complexes. HLA class II-restricted viral antigen presentation by Epstein-Barr virus-transformed B lymphoblastoid cell lines (B-LCL) to CD4+ T cell clones started within 1 h and showed little variability, irrespective of antigen specificity or restriction element tested. In contrast, kinetics of viral antigen presentation by HLA class I molecules to CD8+ T cell clones were slower and differed for three antigen/HLA class I complexes tested. While B-LCL presented antigen by HLA-A2 and by HLA-B37 after at least 2 h, they only started to present antigen in the context of HLA-B7 after more than 4 h. This difference in kinetics did not correlate with differences in bulk transport rates of HLA-A2, HLA-B37, and HLA-B7, but seemed greatly influenced by differential rates of peptide generation. Brefeldin A treatment of B-LCL showed for both HLA class I and class II that de novo synthesized HLA molecules were involved in antigen presentation. Thus, differences between intracellular pathways of HLA class I and class II molecules may result in different kinetics of antigen presentation.

Subacute sclerosing panencephalitis in The Netherlands--1976-1990

Since 1976, when general immunization against measles was introduced in the Netherlands, all new cases of subacute sclerosing panencephalitis (SSPE) were registered and detailed data about immunization, epidemiology and disease progression were collected on them. Up to 1991, 99 new patients have been registered of which 81 were born in this country and 18 elsewhere. From 1981 onwards, the incidence of SSPE among those born in the Netherlands decreased gradually from 13 cases per year to one case per year. This decrease is attributed to the large scale of immunization against measles. Three SSPE patients had been immunized against measles, all of them without a history of clinical measles. Epidemiology and risk factors of SSPE did not differ from those reported in other countries. An exceptional cluster of four patients in one town, who had measles in the same year, is reported. Progression of SSPE appeared to be age related. A total of 28 patients was treated with Inosiplex; no significant effect on survival in stage 3 of the disease was found.

Elevated levels of a soluble form of the T cell activation antigen CD27 in cerebrospinal fluid of multiple sclerosis patients

The expression of the T cell membrane molecule CD27--a molecule that has recently been shown to belong to the nerve growth factor receptor superfamily--is strongly increased after activation of T lymphocytes via the T cell receptor/CD3 complex. In addition, activated cells release a 28-32 kDa soluble form of CD27 in their supernatant which can also be detected in serum and urine of healthy individuals. In this study we show that levels of soluble (s) CD27 are significantly elevated in cerebrospinal fluid (CSF) of multiple sclerosis (MS) patients and of patients and of suffering from other inflammatory neurological diseases (OIND), whereas increased levels of sCD25 (soluble interleukin-2 receptor) were only found in CSF of patients with OIND. In MS patients, a significant correlation was found between CSF sCD27 titer and IgG index.

Allo-cross-reactivity of a human neuraminidase-specific T cell clone dependent on presentation of an endogenous B cell-specific antigen

T cells specific for foreign antigen recognize a complex of peptides and self-major histocompatibility complex (MHC) molecules and can also cross-react with allo-MHC molecules. It remains controversial, however, what alloreactive T cells exactly recognize. It has been proposed that alloreactive T cells recognize endogenous peptides presented by allo-MHC molecules. To test this hypothesis, we examined an influenza virus-specific T cell clone (6H5), specific for neuraminidase N2 and restricted by HLA-DR1. In the absence of influenza virus, this clone cross-reacted with HLA-DR1Dw1+ but not with HLA-DR1Dw20+ Epstein-Barr virus-transformed lymphoblastoid cells (B-LCL). Cold target inhibition experiments and the rearrangement pattern of the T cell receptor beta chain indicated that 6H5 was a monoclonal T cell population most likely using the same T cell receptor for both responses. To determine whether determinants other than HLA-DR1Dw1+ B-LCL or activated B cells, but, surprisingly, not to other cell types expressed HLA-DR1Dw1, including monocytes and transfected L cells. These experiments further support the concept that recognition of allogeneic MHC (in this case HLA-DR1Dw1) may result from a cross-reactivity of T cells specific for a complex of foreign antigen and self-MHC (neuraminidase N2 and HLA-DR1Dw20). Furthermore, allorecognition of T cell clone 6H5 appears to depend upon the recognition of a complex of allogeneic MHC and a cell-type specific endogenous peptide presented by activated B cells.

Analysis of the role of leukocyte function-associated antigen-1 in activation of human influenza virus-specific T cell clones

The role of leukocyte function-associated Ag-1 (LFA-1) in intercellular adhesion is well documented. Previously, we demonstrated that the LFA-1 molecule (CD11a/CD18) can also regulate the induction of proliferation of peripheral blood T cells. In these studies, we observed opposite effects of antibodies against CD11a (LFA-1-alpha-chain) or CD18 (LFA-1-beta-chain). Here, we determined the effects of anti-CD11a and anti-CD18 mAb on proliferation of cloned influenza virus-specific T cells. Anti-CD18 mAb had similar inhibiting effects on the proliferative response of T cell clones induced by immobilized anti-CD3 mAb as it had on the response of peripheral blood T cells. In contrast to its costimulatory effect on resting peripheral blood T cells, anti-CD11a mAb did not increase the proliferation of cloned T cells. Similar differences in effects of anti-CD11a and anti-CD18 mAb were observed when proliferation of the T cell clones was induced by immobilized anti-TCR mAb. When proliferation was induced by influenza virus presented by monocytes as APC, both anti-CD11a and anti-CD18 mAb inhibited T cell proliferation. However, when EBV-transformed B cells were used as APC, neither anti-CD11a nor anti-CD18 mAb inhibited proliferation. These results demonstrate that the effects of antibodies against CD11a (LFA-1-alpha) or CD18 (LFA-1-beta) on T cell proliferation depend on 1) the stage of activation of the T cells, 2) the activation stimulus and its requirement for intercellular adhesion involving LFA-1, and 3) the type of cell used to present Ag.

Analysis of the role of leukocyte function-associated antigen-1 in activation of human influenza virus-specific T cell clones

The role of leukocyte function-associated Ag-1 (LFA-1) in intercellular adhesion is well documented. Previously, we demonstrated that the LFA-1 molecule (CD11a/CD18) can also regulate the induction of proliferation of peripheral blood T cells. In these studies, we observed opposite effects of antibodies against CD11a (LFA-1-alpha-chain) or CD18 (LFA-1-beta-chain). Here, we determined the effects of anti-CD11a and anti-CD18 mAb on proliferation of cloned influenza virus-specific T cells. Anti-CD18 mAb had similar inhibiting effects on the proliferative response of T cell clones induced by immobilized anti-CD3 mAb as it had on the response of peripheral blood T cells. In contrast to its costimulatory effect on resting peripheral blood T cells, anti-CD11a mAb did not increase the proliferation of cloned T cells. Similar differences in effects of anti-CD11a and anti-CD18 mAb were observed when proliferation of the T cell clones was induced by immobilized anti-TCR mAb. When proliferation was induced by influenza virus presented by monocytes as APC, both anti-CD11a and anti-CD18 mAb inhibited T cell proliferation. However, when EBV-transformed B cells were used as APC, neither anti-CD11a nor anti-CD18 mAb inhibited proliferation. These results demonstrate that the effects of antibodies against CD11a (LFA-1-alpha) or CD18 (LFA-1-beta) on T cell proliferation depend on 1) the stage of activation of the T cells, 2) the activation stimulus and its requirement for intercellular adhesion involving LFA-1, and 3) the type of cell used to present Ag.

Relative increase of inflammatory CD4+ T cells in the cerebrospinal fluid of multiple sclerosis patients and control individuals

Of three patients with multiple sclerosis (MS) and two non-MS individuals a large number of CD4+ T cell clones was obtained from the cerebrospinal fluid and peripheral blood by direct limiting dilution. The CD4+ T cell clones from cerebrospinal fluid and peripheral blood lymphocytes were compared for their cytotoxic activity and lymphokine production. Cytotoxic capacity of cloned T cells was analysed with the use of anti-CD3 antibodies and target cells bearing Fc receptors for murine IgG. Recently, we demonstrated the existence of two different subsets of human CD4+ T cell clones by phenotypic and functional criteria. One type of CD4+ T cell with anti-CD3 mediated cytotoxic activity, in analogy with murine studies, is the inflammatory or TH1 subtype, the main producer of interleukin (IL-2), interferon-gamma (IFN-gamma) and tumour necrosis factor (TNF)-alpha, -beta, whereas the other type of CD4+ T cell clone lacked anti-CD3 mediated cytotoxicity and produced minimal amounts of IL-2 concomitant with reduced levels of IFN-gamma and TNF-alpha, -beta. The present study demonstrates that among three MS patients, relatively more inflammatory CD4+ T cell clones with cytotoxic activity and IFN-gamma and TNF-alpha, -beta production were derived from the cerebrospinal fluid as compared with peripheral blood lymphocytes. Also among control individuals more inflammatory CD4+ T cell clones could be obtained from the cerebrospinal fluid as from the peripheral blood. The enrichment of inflammatory CD4+ T cells, therefore, appears to be physiological rather than associated with the disease.

Magnetic resonance imaging studies in multiple sclerosis twins

Magnetic resonance (MR) imaging examinations were performed on a series of seven sets of twins (four monozygotic and three dizygotic) and one set of triplets who were clinically discordant for multiple sclerosis (MS). MR abnormalities were detected in some of the unaffected monozygotic pairs of twins.

Influenza virus changes cell-surface glycoproteins including major histocompatibility complex determinants on lymphocytes

The effect of influenza virus infection on the expression of major histocompatibility complex (MHC) antigens was investigated. Infection with influenza virus resulted in an increase of the binding of anti-MHC class I and class II antibodies to resting T cells. The binding of anti-MHC class II antibodies to activated T cells was increased approximately threefold. The binding of anti-MHC class I and class II antibodies to Epstein-Barr virus-transformed B cells appeared unaffected after influenza virus infection. Recombinant human interferon-alpha and/or -gamma added to T cells did not enhance the binding of anti-MHC antibodies. Biochemical analysis revealed no increase in the amount of class I and class II antigens as a consequence of viral infection, but a marked decrease in sialic acid content was found, most probably caused by the viral neuraminidase. Pulse-chase experiments suggest that the viral neuraminidase can catalyze the removal of sialic acids both en route to and at the cell surface. The absence of sialic acid residues can explain the increased binding of anti-MHC antibodies, because neuraminidase (clostridium perfringens) treatment of T and Epstein-Barr virus-transformed B cells resulted in a shift in both isoelectric point and antibody binding similar to that observed after influenza virus infection.

Cytotoxic T-cell response to influenza A subunit vaccine in patients with type 1 diabetes mellitus

The cytotoxic T-cell and humoral immune response to a commercially available influenza A-H1N1 subunit vaccine in 14 patients with type 1 diabetes mellitus was compared with the response in 13 healthy volunteers. Cytotoxic T-cell response to vaccination was poor in both patients and controls. At a calculated 50: 1 effector-target cell ratio, however, significantly more controls than patients showed an increase of over 5% cytotoxic T-cell mediated lysis after vaccination (P less than 0.05). In patients the cytotoxic T-cell response decreased with higher percentages of glycosylated haemoglobin (regression coefficient not equal to 0 with P less than 0.05). No significant difference was found between diabetic patients and control subjects with respect to antibody response after vaccination. Implications for vaccination strategy are discussed.

Clonal analysis of functionally distinct human CD4+ T cell subsets

A large number of CD4+ T cell clones, obtained from peripheral blood T lymphocytes by direct limiting dilution, allowed us to address the question whether functional heterogeneity exists within the human CD4+ T cell subset. Cytotoxic capacity of cloned T cells was analyzed with the use of anti-CD3 antibodies and target cells bearing FcR for murine IgG. 6 of 12 CD4+ clones obtained were able to lyse Daudi or P815 cells in the presence of anti-CD3 antibodies. The remaining six CD4+ T cell clones tested did not display anti-CD3-mediated cytotoxic activity and did not acquire this cytotoxic capacity during a culture period of 20 wk. In the absence of anti-CD3 mAb, no lytic activity against Daudi, P815, and K562 target cells was observed under normal culture conditions. Phenotypic analysis of these two distinct types of CD4+ T cells did not reveal differences with regard to reactivity with CDw29 (4B4) and CD45R (2H4) mAbs that have been described to recognize antigens associated with helper suppressor/inducer (respectively) CD4+ cells. The CD4+ clones without anti-CD3-mediated cytotoxic activities (Th2) consistently showed a high expression level of CD28 antigens, whereas the cytotoxic clones (Th1) expressed low amounts of CD28. Th1 CD4+ clones did produce IL-2, IFN-gamma, and TNF-alpha/beta, whereas the Th2 T cell clones produced minimal amounts of IL-2 and only low levels of INF-gamma and TNF-alpha/beta in response to anti-CD3 mAbs and PMA. Although not all CD4+ clones did release IL-4, there was no correlation with cytotoxic activity. Moreover, as compared with the Th1 CD4+ clones, Th2 CD4+ T cell clones proliferated moderately in response to immobilized anti-CD3 mAbs. However, proliferation reached the level of the cytotoxic clones when anti-CD28 mABs were present during culture. Both CD4+ subsets provided help for B cell differentiation upon stimulation with anti-CD3 mAbs. Our data suggest that the human CD4+ subset, in analogy to the murine system, comprises two functionally distinct T cell subpopulations, both of which are able to exert helper activity for polyclonal B cell differentiation, but which differ in cytotoxic capacity, lymphokine production, and requirements for proliferation. A function for these two types of T cells in the immune response is discussed.

Recognition of influenza virus-infected B-cell lines by human influenza virus-specific CTL

The cytotoxic activity on influenza virus-infected Epstein-Barr virus (EBV)-transformed B-lymphoblastoid cell lines (LCL-Flu) and influenza virus-infected phytohemagglutinin lymphoblasts (PHA-Flu) was compared with the use of influenza-A virus-specific cytotoxic T lymphocytes (CTL), generated in short-term bulk cultures. Cold-target inhibition experiments showed that the lysis of PHA-Flu was completely blocked by both cold LCL-Flu and cold PHA-Flu whereas the lysis of LCL-Flu was completely inhibited by cold LCL-Flu, but only partially by cold PHA-Flu, indicating that structures can be recognized on LCL-Flu which are absent from PHA-Flu. Monoclonal antibody (McAb) directed against a monomorphic determinant of major histocompatibility complex (MHC) class I molecules inhibited the lysis of PHA-Flu more strongly than the lysis of LCL-Flu. Since LCL have a high expression of MHC class II molecules compared to PHA lymphoblasts, we examined whether class II-restricted CTL activity was responsible for the (anti)class I McAb-resistant lysis of LCL-Flu. Neither anti-CD4 McAb nor anti-class II McAb inhibited the lysis of LCL-Flu which argues against a contribution of MHC class II-restricted CTL. Depletion of CD16+ cells, containing the majority of the nonspecific cytotoxic cells, did not affect the lysis of LCL-Flu, indicating that the remaining lysis on LCL-Flu was also not due to a nonspecific component. We suggest that cell-type-dependent variations exist in the nature of the immunogenic determinants to which CTL respond.

Role of IL-2 and interferon in the generation of natural cytotoxic activity in influenza virus-stimulated PBL cultures: analysis with the use of prednisolone

We have examined the role of interleukin 2, interferon-gamma and interferon-alpha in the generation of natural cytotoxic (NC) activity and cytotoxic T-lymphocyte (CTL) activity in peripheral blood lymphocyte cultures stimulated with influenza virus, using the immunosuppressive effects of prednisolone. In addition to an inhibitory effect on the generation of CTL activity, prednisolone also inhibited the generation of NC activity in a similar dose-and time-dependent manner. Prednisolone suppressed the production of interferon-gamma when it was added on the first day of culture of PBL with influenza virus. Levels of interferon-alpha were not affected. The effects of prednisolone on the generation of NC activity and CTL activity in kinetic terms were not paralleled by the effects on interferon-alpha and interferon-gamma production. The diminished generation of NC activity could be reversed by the addition of interleukin 2 (IL-2), but interferon-gamma had little if any restorative effects. Interferon-alpha had no effect. These findings support the hypothesis that IL-2 is the major inducer of NC activity in CTL generation cultures. The inhibitory effect on CTL generation could only be reversed by IL-2 and not by interferon-alpha- and interferon-gamma. Thus, in the absence of IL-2, interferon-alpha and interferon-gamma cannot support the generation of CTL activity or the concomitantly induced NC activity.

Inactivation of 12 viruses by heating steps applied during manufacture of a hepatitis B vaccine

The efficacy of two heating cycles (90 sec at 103 degrees C and 10 hr at 65 degrees C) used during manufacture of a plasma-derived hepatitis-B vaccine was validated for the inactivation of 12 virus families. A period of 15 min warming up to 65 degrees C had already completely inactivated representatives of nine virus families, ie, poxvirus (vaccinia), picornavirus (encephalomyocarditis virus), togavirus (sindbis virus), coronavirus (mouse hepatitis virus), orthomyxovirus (influenza virus), rhabdovirus (vesicular stomatitis virus), herpes virus (cytomegalovirus), lentivirus (human immunodeficiency virus), and retrovirus (murine leukemia virus). After prolonged heating at 65 degrees C or heating for 90 sec at 103 degrees C, parvovirus (canine parvovirus) and the phage phiX174 were also completely inactivated. Papovavirus represented by simian virus 40 (SV-40) was the most heat-resistant virus evaluated. The infectivity of SV-40 was reduced by 10(4) Tissue Culture Infectious Doses (TCID50) per ml after 90 sec at 103 degrees C, but a marginal residual activity (less than 1.5 TCID50 per ml) was observed. Subsequent pasteurization for 10 h at 65 degrees C did not further reduce the infectivity of SV-40. This study shows that the two heat-inactivation steps used during the production of this vaccine kill a wide variety of viruses that might be present in human blood.

Natural cytotoxic activity in multiple sclerosis patients: defects in IL-2/interferon gamma-regulatory circuit

In order to determine the factors underlying the impaired natural cytotoxic (NC) activity in multiple sclerosis (MS) patients, we have analysed the interleukin 2 (IL-2)-interferon gamma-(IFN gamma)-NC activity regulatory circuit in 40 MS patients and 40 matched healthy controls. Exogenous recombinant IFN gamma (rIFN gamma) enhanced NC activity in peripheral blood lymphocytes (PBL) derived from MS patients and controls equally well. In contrast, PBL from MS patients showed a significantly lower increase of NC activity in response to IL-2 than healthy controls. This defect in responsiveness was independent of the dose of IL-2. Even at the highest dose of rIL-2 (1000 U/ml), MS patients showed a decreased response. PBL from MS patients required a 2 to 10 times higher dose of IL-2 to reach NC activity levels comparable to controls. In healthy individuals IL-2 can act upon both Fc gamma R+ and Fc gamma R- NC precursor cells. The decreased responsiveness to IL-2 is not confined to one subpopulation of IL-2-responsive precursor cells because depletion of Fc gamma R+ cells before culture in the presence of IL-2 revealed no significant differences in the contribution of Fc gamma R+ precursor cells to the IL-2 enhanced NC activity between MS patients and controls. Also the number of IL-2-responsive precursor cells appeared to be normal since the number of Fc gamma R+ cells in MS patients and controls was comparable. PBL from MS patients produced significantly lower amounts of IFN gamma upon stimulation with IL-2. Analysis of the different parameters of the regulatory circuit at the population level showed, both for patients and controls, a significant correlation between IFN gamma production and increase of NC activity induced by IL-2. Also the endogenous NC activity and IFN gamma production, both in patients and controls, were correlated. At the individual level, defects in NC activity could not be linked to another parameter of the regulatory circuit.

Thermal inactivation of human immunodeficiency virus in lyophilised blood products evaluated by ID50 titrations

Inactivation of human immunodeficiency virus (HIV) in lyophilised small pool cryoprecipitate, factor VIII concentrate, prothrombin complex and C1-esterase inhibitor concentrate by prolonged heat treatment (72 h, 60 degrees C) was studied. Plasma products, inoculated prior to lyophilisation, had infectious titres ranging from 10(7) to 10(10.5). Residual infectivity (TCID50) was assessed by multiple titrations on H9 cells in a macro system and subsequent detection of virus replication by determining reverse transcriptase activity. Kinetics of inactivation showed a biphasic pattern: during the first 8 h a variable TCID50 reduction up to 10(4.3) was observed, followed by an additional loss of 10(1)-10(2.7) during the next 64 h. Heat treatment for 72 h resulted in a mean TCID50 reduction of 10(5). It is concluded that prolonged heat treatment may lead to the adequate prevention of HIV transmission by lyophilised plasma products.

The role of IL-2 and T4+ cells in the generation of human influenza virus-specific CTL activity

Stimulation of human peripheral blood lymphocytes (PBL) with influenza A virus leads to the generation of virus-specific cytotoxic T lymphocyte (CTL) activity as well as natural killer (NK)-like activity. In this study, we show that exogenous IL-2 augments the in vitro generation of virus-specific CTL activity, only when added some days after the initiation of the culture. Apparently, the endogenously produced IL-2 can be a limiting factor in the in vitro generation of CTL activity. The increase of influenza virus-specific CTL activity after addition of exogenous IL-2 does not affect the restriction pattern of the CTL response. So, the preferential use of certain HLA antigens as restriction elements is not due to a limiting amount of endogenously produced IL-2. Depletion of T4+ cells completely abrogates the generation of virus-specific CTL activity. Addition of exogenous IL-2 to T4+-cell-depleted cultures fully restores the generation of HLA-restricted virus-specific CTL activity. We conclude that in the in vitro generation of virus-specific CTL activity in bulk cultures of human PBL the sole function of T4+ cells in human virus-specific CTL generation is the production of IL-2, no cognitive cell interaction of T8+ CTL precursors with T4+ cells is required, and in bulk cultures T8+ cells themselves are not able to produce sufficient amounts of IL-2 to ascertain the maturation of virus-specific CTL precursors into cytolytic T cells. Finally, we show that exogenous IL-2 also has a stimulatory effect on the NK-like or lymphokine-activated killer activity, which is always concomitantly induced in virus-specific CTL generation cultures, but has no influence on the levels of IFN produced in such cultures.

IL-2- and IFN gamma-enhanced natural cytotoxic activity: analysis of the role of different lymphoid subsets and implications for activation routes

To elucidate the immunoregulatory mechanisms by which human recombinant interleukin 2 (r.IL-2) and human recombinant interferon (IFN)-gamma influence natural cytotoxic activity of human peripheral blood lymphocytes (PBL), experiments were performed in which we studied: the kinetics of augmentation of natural cytotoxic activity by IL-2 and IFN-gamma; the phenotypes of the natural cytotoxic precursor cells acted upon by IL-2 and IFN-gamma; the role of IL-2-induced IFN-gamma in the natural cytotoxic activity enhancing effects of IL-2 and (d) the surface phenotypes of the natural cytotoxic cells activated by IL-2 or IFN-gamma. Three phenotypical distinct precursor cells can be identified. The phenotypes of the precursor cells sensitive to r.IFN-gamma are T3-, Leu 7+or-, FcR-gamma+. The phenotypes of the precursor cells sensitive to r.IL-2 are T3-, Leu 7-, FcR-gamma+or-. It appears that during prolonged culture relatively more of the FcR-gamma- precursor cells acquire natural cytotoxic activity upon stimulation with r.IL-2. Antibodies to IFN-gamma, known to neutralize both recombinant and natural IFN-gamma, completely inhibited the IFN-gamma-induced augmentation of natural cytotoxic activity but only slightly affected the IL-2-mediated augmentation. This indicates that only part of the augmenting effect of r.IL-2 is mediated through IL-2-induced IFN-gamma. This implies that r.IL-2 augments natural cytotoxic activity predominantly through an IFN-gamma-independent pathway. The phenotype of the effector cells expressing natural cytotoxic activity after a 4-day culture period with IL-2 or IFN-gamma was analyzed by depletion experiments. Virtually all the cells that exerted the IFN-gamma-enhanced natural cytotoxic activity are FcR-gamma+, whereas a portion of the cells that exerted the IFN-gamma-enhanced natural cytotoxic activity are FCR-gamma-. Both natural killer cells and lymphokine-activated killer cells contribute to natural cytotoxic activity. The relative contributions of both activities to the natural cytotoxic activity augmented by IL-2, respectively, IFN-gamma, is discussed.

Asymmetry in the recognition of HLA-A3 molecules by virus-specific cytotoxic T cells

Cytotoxic T cells specific for influenza virus A/HK or Epstein-Barr virus were used to study the heterogeneity of the HLA-A3 molecule. Variability of the recognition of HLA-A3 in both systems was observed. The hierarchy was both effector cell and target cell specific. An extreme example of the hierarchy of HLA-A3 recognition is the following. Virus-specific cytotoxic T lymphocytes of a given donor were found to recognize all HLA-A3-matched target cells, including target cells of a donor from whom the virus-specific effector cells did not recognize target cells of that given donor: Donor A recognizes target B but donor B does not recognize target A. Both will recognize a third HLA-A3-matched target cell C. Cold target inhibition studies confirmed that the recognition of target cell B by effector cell A involved the recognition of only HLA-A3. Examples of such asymmetric recognition were found in both influenza A and Epstein-Barr virus-specific cytotoxic T-lymphocyte responses but not one combination was asymmetric in both systems. This suggests that influenza virus A/HK-specific cytotoxic T lymphocytes recognize other HLA-A3 histotopes than do Epstein-Barr virus-specific cytotoxic T lymphocytes.

Subtypes of HLA-B27 detected by cytotoxic T lymphocytes and their role in self-recognition

In the present study cytotoxic T lymphocytes were generated in MLC of lymphocytes from two unrelated HLA-A, B, C-identical, B27-positive, but D/DR-different, individuals. These CTL were shown to detect subtypes of HLA-B27. CTL specific for influenza virus lysed infected target cells matched for HLA-B27 only when they shared the same subtype. This indicates that the two subtypes of HLA-B27 detected by CTL function also as distinct elements in a self-restricted CTL response. Both subtypes were found among patients with ankylosing spondylitis.

Killing of measles virus-infected cells by human cytotoxic T cells

Lymphocytes from normal individuals were tested for the capacity to generate measles virus-specific cytotoxic T-cell responses after in vitro stimulation with measles virus. Approximately 12% (5 of 40) of the normal adults tested produced significant cytotoxic responses. The cytotoxic response was measles virus specific both at the level of stimulation and at the effector level. Studies of the specificity of cytotoxic effectors from five normal donors by direct lysis or cold target inhibition or both indicated that most, if not all, of the virus-specific activity was self-specific. A detailed analysis of one donor (W6) indicated that measles-specific cytotoxicity was largely HLA-A and -B restricted; unexplained cross-reactive lysis was observed with some targets, but this lysis appeared to be HLA related, since all of the targets expressed HLA-B12. An analysis of the cellular requirements for the production of measles-immune cytotoxic T lymphocytes demonstrated that T cells and macrophages (depleted of natural killer and K cells) were sufficient for the generation of killer cells. Most of the cytotoxic effector activity was mediated by OKT3+ OKT4- OKT8+ cells.

Cytotoxic T lymphocyte responses against alloantigens exhibit preferential effector cell activity for H-2K or H-2D region products similar to that for H-2 restricted responses

The present study was designed to investigate the patterns of allogeneic cytotoxic T cell responses against H-2K and H-2D region products. B10.D2 anti-B10.A(2R) effector cells lysed K-end matched target cells approximately 5 times more efficiently than D-end matched target cells. In contrast, C57BL/10 anti-B10.A effector cells killed K-end or D-end matched target cells equally well, whereas C57BL/10 anti-B10.D2 CTL exhibited a slight preference for D-end matched target cells. These results demonstrate that whole H-2 disparate stimulating populations do not necessarily induce equivalent h-2K and H-2D region-specific CTL responses. The strength of the cytotoxic responses was found to correlate with the number of known serologically detectable specificities shared between the stimulating and target cell populations. The similarities between these allogeneic and MHC-restricted CTL response patterns (which are under Ir-like control) raise the possibility that this regulation reflects the number of K or D region self-antigens that can be recognized in association with a foreign antigenic determinant and suggests that allogeneic responses to major histocompatibility antigens are also self-restricted by MHC gene products. The possibility is considered that such Ir-like control is also a reflection of the amounts of H-2K and H-2D products shed from the cell surface.

Cytotoxic T lymphocyte responses against alloantigens exhibit preferential effector cell activity for H-2K or H-2D region products similar to that for H-2 restricted responses

The present study was designed to investigate the patterns of allogeneic cytotoxic T cell responses against H-2K and H-2D region products. B10.D2 anti-B10.A(2R) effector cells lysed K-end matched target cells approximately 5 times more efficiently than D-end matched target cells. In contrast, C57BL/10 anti-B10.A effector cells killed K-end or D-end matched target cells equally well, whereas C57BL/10 anti-B10.D2 CTL exhibited a slight preference for D-end matched target cells. These results demonstrate that whole H-2 disparate stimulating populations do not necessarily induce equivalent h-2K and H-2D region-specific CTL responses. The strength of the cytotoxic responses was found to correlate with the number of known serologically detectable specificities shared between the stimulating and target cell populations. The similarities between these allogeneic and MHC-restricted CTL response patterns (which are under Ir-like control) raise the possibility that this regulation reflects the number of K or D region self-antigens that can be recognized in association with a foreign antigenic determinant and suggests that allogeneic responses to major histocompatibility antigens are also self-restricted by MHC gene products. The possibility is considered that such Ir-like control is also a reflection of the amounts of H-2K and H-2D products shed from the cell surface.

Activation of measles virus from silently infected human lymphocytes

Lymphocytes were incubated with measles virus for 4 days in the absence of a lymphocyte stimulating agent. Such nonstimulated lymphocytes, infected with measles virus, did not express the virus antigens that are detectable by cytotoxic antibodies. Approximately 1 out of 5,000, or even fewer, of such lymphocytes produced virus as demonstrated by the infectious center assay; in the supernate only 10--100 infectious viruses per milliliter were detected. No virus structures could be observed by means of an electron microscope. However, such lymphocytes showed no reaction to phytohemagglutinin (PHA) in terms of DNA synthesis in a subsequent culture in the presence of antibodies against measles to prevent spreading of the infection to other cells. Although stimulation by PHA did not result in a significant increase in [3H]thymidine incorporation, measles virus was activated; 32 h after the addition of PHA nearly 80% of the cells were killed by measles virus antibodies and complement. The number of virus-producing cells increased to approximately 1 in 300 or more, and at 72 h the virus titer in the supernate had risen to 10(6) infectious particles per ml. This reactivation of measles virus was still obtained when PHA was added as late as 8 or more days after the initial infection.

Sex differences, personality and study difficulty in university students

A study difficulty inventory and three sets of personality scales were administered to 145 students attending a university health centre. Motivational and psychoneurotic components of study difficulty were identified, which were differentially related in male and female students to basic personality characteristics and to psychiatric symptomatology. Syllabus-boundness emerged as more salient in the female students, and self-esteem in the males. Poor academic performance was found to be associated with distinctive personality profiles in the two sexes. Both intra-personality and social–psychological interactional factors appear to underlie the pattern of results.

Personality correlates of study difficulty and academic performance in university students. I. The Middlesex Hospital Questionnaire and Dynamic Personality Inventory

The personality correlates of study difficulty and academic performance in university students have been measured in terms of psychiatric symptomatology and premorbid characteristics. The UCLSQ, MHQ and DPI were administered to two groups of male and female students presenting at an health centre: one (n = 72) of patients seeking psychological help, the other (n = 73) a control group. Significant differences between the two groups were formed on the MHQ, confirming previous results; and these were supplemented by differences on the DPI. Motivational and psychoneurotic components of study difficulty were significantly related to MHQ scores in both groups. DPI scores were more closely related to study difficulty in the patients than controls; and served particularly to characterize their sylbism and work satisfaction. The DPI added to the picture of a subgroup of students observed both in an earlier and the present study: academically successful patients scoring high on phobic anxiety.

Personality correlates of study difficulty and academic performance in university students. II. Conscience and self-esteem

Scales measuring self-esteem and conscience have been included in a further study of work-related symptoms in students. Two groups were tested: a group of patients attending the UCL Student Health Centre for psychological reasons, and a group of normal controls. Conscience and self-esteem were inversely related to one another. Both tests were reliable and differentiated between the groups. The patients tend to have low self-esteem, high conscience, and to score higher than controls both on neurotic symptoms as such as measured by a personality inventory (MHQ) and as assessed on work-related symptoms measured by our study difficulty questionnaire (UCLSQ). In terms of academic performance, an interesting subgroup of students was delineated who are rated highly by their tutors but who appear subjectively troubled with phobic anxiety, low self-esteem and a harsh conscience structure. The conscience and self-esteem scales, in view of their brevity, acceptable reliability, and in terms of the relationships discussed in this paper, will be retained for further research.

Further observation on study difficulty in university students including 'syllabus-boundess'

The UCLS questionnaire, in a form modified to include a measure of syllabus-boundness, and a questionnaire to measure psychiatric symptomatology (the MHQ) were administered to two groups of students, one seeking help for emotional problems, the other a control group. Groups were compared on tests, test findings were inter-correlated, and scores were related to academic success. The UCLSQ is confirmed as a reliable research instrument. Principal component analysis again indicates a separation of psychoneurotic and motivational components of study difficulty. Syllabus-boundness ('Sylbism') emerges as a relatively independent trait, with a significant negative relationship to work satisfaction in both groups. MHQ scores again show a positive correlation between phobic anxiety and academic attainment for patients.

Physico-chemical and immunological properties of acid alpha-glucosidase from various human tissues in relation to glycogenosis type II (Pompe's disease)

The physico-chemical and immunological properties of acid alpha-glucosidase from various human tissues have been studied. Heat stability of acid alpha-glucosidase from heart, liver and skeletal muscle is identical, but for kidney some different results are obtained. Identical isoelectrofocussing patterns are found for heart, liver and skeletal muscle. Furthermore, the effect of antiserum against human liver acid alpha-glucosidase on the activity of acid alpha-glucosidase from various tissues is studied. The results are discussed in relation to glycogenosis type II (Pompe's disease).

Tubuloreticular structures in human lymphoid cell lines. A cell biological study

Human lymphoid cell lines were studied as an experimental model for the spontaneous or induced occurrence of tuburloreticular structures (TRS). It was possible to induce TRS after culturing the EB-3 cell line with 20 mug/ml bromodeoxyuridine (BrUdR) during 96 h. Starvation, culturing at lower temperature (32 degrees) or inhibition of DNA synthesis did not give rise to the production of TRS. The response to BrUdR could be blocked with 60 mug/ml thymidine but not with 60 mug/ml deoxycytidine. The addition of 5 mug/ml cytarabine or the removal of BrUdR at different times resulted in inhibition of TRS induction, indicating that BrUdR had to be incorporated into DNA during at least 48 h. After incorporation, neither the presence of BrUdR nor DNA synthesis was necessary for the production of TRS. These experiments and the finding that in the cell line IHTC-33, which does not produce Epstein-Barr virus associated antigens, TRS were spontaneously present, exclude a correlation between TRS and these antigens. However, the induction of TRS by BrUdR may be related to the activation of another (latent) virus.

Concepts and methods in student mental health

Considering their potential contribution to the community, the growth of clinical services in relation to the specialized mental health problems of students in higher education has been haphazard. Although most universities have developed or are on the way to developing comprehensive health services on the lines recommended in the report of the Royal College of Physicians (1966), services in the non-university sector are often less than adequate. This report accepted as established that about 5 per cent of students have psychological disorders which cause serious distress, and a further 10 to 20 per cent have less severe though handicapping disorders. It was accepted that special provision would need to be made for these mental health problems, as part of the range of preventive and treatment activities relevant to a College community.

The delineation and measurement of study difficulty in university students

Psychiatric disturbances in a student population span a broad spectrum and include overt illness, a heterogeneous group of psychosocial problems with varied and changing symptomatology and normal crises of development. Complaints of work difficulty often form part of the symptomatology of all these groups, and not infrequently may be the presenting symptom. Quantification is difficult because the symptoms vary in degree and form, and change over time. They may be unreported or voiced only to friends or tutors. Their prevalence and significance is therefore hard to assess. In a cohort study spanning a four year period, Lucas (unpublished data) found that of the 15 per cent of the cohort who received brief psychotherapy, more than three-quarters had a work difficulty of some kind. Of the 26 per cent of the cohort who never attended the Student Health Centre nearly half replied ‘yes' to a question asking whether they had experienced recurring work difficulty.

Interaction in university selection, mental health and academic performance

The last decade has seen a shift in the emphasis of research into student problems and student performance. On the psychological side there has been a move away from somewhat static concepts of personality measurement and intellectual assessment, and the concomitant preoccupation with prediction and selection, towards a more interactive approach in which individual aspects are related to academic and social processes (e.g. Sanford, 1962; Lavin, 1965; Wankowski, 1969). On the mental health side there has been a shift from 'syndrome identification’ towards a more dynamic appraisal of personal and social forces and their interaction (Grant, 1969; Ryle, 1969; Lucas and Linken, (1970).