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We present a dense STR/linkage disequilibrium(LD)/gene map between the RING3 and HLA-B loci, reference allelic sizes on the most prevalent HLA haplotypes and their allelic frequencies in pedigree founders. This resource will facilitate LD, evolution and gene mapping studies, including comparisons of HLA and STR haplotypes and identification of HLA recombinants. The map was constructed by testing novel and previously reported STRs using a panel of 885 individuals in 211 families and 60 DNA samples from cell lines and bone marrow donors homozygous in the HLA-A, -B and -DR loci selected from over 15 000 entries into the registry of Swedish bone marrow donors. We have also analysed the variability of STR alleles/haplotypes on the most prevalent HLA haplotypes to identify STRs useful for fine mapping of disease genes in the region previously implicated in susceptibility to many disorders. The analysis of 40 HLA-A*01, B*0801, DRB1*03011, DQB1*0201 haplotypes in homozygous donors showed a surprising stability in 23 STRs between the class II recombination hot spot and HLA-B, with the average of 1.9% (16/838) variant alleles. However, 40% variant alleles were found at the D6S2670 locus in intron 19 of the tenascin-X gene both in the families and homozygous donors. The nucleotide sequence analysis of this STR showed a complex polymorphism consisting of tetra- (CTTT)(8-18) and penta-nucleotide (CTTTT)(1-2) repeats, separated by an intervening non-polymorphic sequence of 42 bp. The HLA-A1, B*0801, DRB1*03011, DQB1*0201 haplotypes had five (CTTT)(14-18)/(CTTTT)(2) variants with a predominant (CTTT)(16) allele, implicating the tetranucleotide component as the source of this ancestral haplotype diversification, which may be due to the location of D6S2670 in the region of the highest GC content in the human MHC.

This paper compares the total inventory costs (TIC) of five lot-sizing techniques. The add-drop heuristic (ADH) is a capacitated technique and the lot-for-lot (L4L), fixed period quantity (FPQ), least unit cost (LUC) and the silver-meal heuristic (SMH) are uncapacitated techniques. The TIC is considered as a function of the reorder interval (RI). This comparison is based on the assumption that if both capacitated and uncapacitated techniques produce identical RIs, then their TICs must also be identical (although uncapacitated techniques do not reflect this fact). Empirical results suggest that the ADH technique yields considerably better (i.e. lower) TICs when the demand levels and the number of items are low. On the other hand, these results suggest that for high demand levels, the TICs of the four popular lot-sizing techniques are close to the near optimal cost obtained by the (most time-consuming) ADH technique. Some theoretical results on the performance of uncapacitated techniques are also presented.

SUMMARYAbsolute and relative NK cell numbers were determined in peripheral whole blood by flow cytometry in patients with common variable immunodeficiency (CVID) (n = 55) and X-linked agammaglobulinaemia (XLA) (n = 19) on regular immunoglobulin (IVIG) therapy. Absolute CD3−CD16+ NK cell numbers were significantly reduced in CVID patients (median 108/μl, range 23–815), compared with normal subjects (n = 60) (289/μl, range 56–640, P

We examined the effects of intravenous immunoglobulin (IVIG) on cytokine regulation in vivo using samples taken before and after replacement-dose (200–400 mg/kg) IVIG in a group of patients with common variable immunodeficiency (CVID) and X-linked agammaglobulinaemia (XLA). The intracellular cytokine content of CD4+ and CD8+ lymphocytes, and their CD28+/− subsets, were measured following in vitro activation with phorbol myristate acetate (PMA) and ionomycin. The cytokines IL-2, interferon-gamma (IFN-γ) and tumour necrosis factor-alpha (TNF-α), and the early activation marker CD69, were assessed by four-colour flow cytometry of whole blood cultures taken before and after IVIG infusion. There was a significant increase in IL-2 expression in CD4+ (and CD4+28−) cells and an increase in TNF-α expression in CD8+28− cells following IVIG in CVID, but not in XLA patients. IFN-γ and CD69 expression were not affected by IVIG infusion. This increase in TNF-α and IL-2, combined with unchanged IFN-γ expression, is evidence against the putative ‘anti-inflammatory’ role of IVIG, and may explain the failure of resolution of granulomata in CVID patients treated with IVIG alone.

This experiment was designed to test the construct validity of psychometric analyses that suggested a strong functional association between the accuracy for toe graphaesthesia and selective activation of neurons within the medial prefrontal regions. Single Photon Emission Computerized Tomography (SPECT) profiles were obtained for three volunteers (2 men, 1 woman) after they had been exposed to a toe graphaesthesia task or had been exposed to the control setting. The two measurements for each participant were separated by at least one week. Qualitative evaluation, using criteria employed for clinical diagnoses, of serial coronal, sagittal, and horizontal sections clearly indicated a specific increase in uptake of tracer within the rostral one-third to one-half of the medial prefrontal cortices of all three subjects during the toe graphaesthesia task compared to that during baseline conditions. The results are consistent with our neuropsychological research which indicates that toe graphaesthesia may be an accurate and useful indicator of the functional integrity of the medial surfaces of the anterior cerebral hemispheres.

Hyper-IgM (HIM) syndrome is a rare primary immunodeficiency disorder. Approximately 120 cases have been described in the literature world-wide. Features of HIM include low serum IgG, a very low IgA with normal or high IgM levels. Autoimmune phenomena are recognized associations but connective tissue disorders have so far not been described in HIM patients. We report the case of a 19-year-old Indian woman with an immunodeficiency syndrome characteristic of non-X-linked HIM who developed discoid lupus erythematosus. Anti-double-stranded DNA antibodies were negative. Antibodies to extractable nuclear antigens were positive for Ro and nRNP, with evidence that they were of both IgG and IgM class. Treatment with hydroxychloroquine and topical steroids was successful.

Data from a low-latitude ground array of 10 fluxgate magnetometer stations spanning a geomagnetic latitude range from 38°N through the equator to 47°S, with a geomagnetic longitudinal extent from 185°E to 227°E covering ∼3 hours in magnetic local time, and an additional high-latitude station (65°N) are used to study the spatial and conjugate properties of Pi2 geomagnetic pulsation wave frequency, amplitude, phase, and polarization. Using fast fourier transform and pure state vector analysis techniques, multistation observations show that individual frequency elements of the Pi2 waves are constant with latitude and longitude, but the dominant frequency may vary. In fact, the higher frequencies often dominate at low latitudes, and the lower frequencies often dominate at higher latitudes. The D component amplitude shows a clearly decreasing trend to a near-zero minimum at the equator, while the H component amplitude does not show a simple behavior. The H component phase is nearly constant at low latitudes, while the high-latitude station may be out of phase or in phase with the low-latitude stations for different events. The D component phase is constant in each hemisphere with a 180° phase difference between hemispheres. Azimuthal wave numbers m obtained from interstation phase differences are small, typically |m| < 3, and show a dominance of westward propagation at most longitudes. It is concluded that the main features of low-latitude Pi2 properties are most easily explained by magnetospheric cavity or wave guide mode resonances, and field line resonances are most likely responsible for the high-latitude Pi2s. This supports the idea that midlatitude and low-latitude Pi2s are two-source phenomena.

A survey of 358 patients with primary antibody deficiency shows that mycoplasmal infection is the commonest cause of severe chronic erosive arthritis. We review our experience with 18 patients with confirmed or probable mycoplasmal arthritis. There was a broad spectrum of severity from a monoarthritis rapidly responding to tetracyclines to severe debilitating polyarthritis, sometimes with antibiotic-resistant organisms which in two cases were eliminated following hyperimmune animal serum therapy. Most patients had very low serum 1gG levels at the onset of arthritis, suggesting that maintaining levels within the normal range with immunoglobulin replacement may prevent infection. The unique susceptibility of these patients to mycoplasmal arthritis shows that antibodies play a crucial role in protection against these organisms.

SUMMARY Several T cell defects have been described in the antibody deficiency disease, CVID, but there have been few data on the generation of responses of specific T cell populations to primary neoantigens. We have now used immunization with the neoantigens, keyhole limpet haemocyanin (KLH) and DNP-Ficoll, to evaluate immune responses in CVID patients and normal donors. B and T cell responses were examined 2 and 4 weeks post-immunization. Sera were examined for IgM and IgG anti-KLH responses by ELISA and for anti-DNP-Ficoll activity by haemagglutination. The frequency of KLH-responsive T cells was measured by DNA synthesis in a limiting dilution culture system. Low density cells enriched for dendritic cells were pulsed with KLH and cultured with different numbers of autologous T cells. T cells from normal donors and from patients showed a low frequency of antigen-specific precursor T cells (≤1:200 000). After KLH immunization the frequency increased in normal donors (1:60 000 and 1:30 000 at 2 and 4 weeks, respectively), while in CVID patients it did not change from the pre-immunization level. The defect may extend to a dysfunction of antigen-specific cells, rather than being solely due to the reduced numbers of cells, since mean responses of ‘positive’ wells were also reduced. The serum-specific antibody response paralleled the T cell data, in that all normal donors but none of the CVID patients generated IgG KLH-specific antibodies. CVID patients did produce IgM antibodies against the T-independent DNP-Ficoll, but at a lower level than normal controls. These data show that both T and B cells from CVID patients have defective responses to specific antigen, implicating both lineages in the antibody deficiency.

This qualitative study seeks to locate those needs which teachers of religious education have in their initial year of teaching at the secondary level. It uses two instruments, a case study and a questionnaire, to obtain this information.The results of the study raise important questions relating to the provision of in‐service training, the Post Graduate Certificate in Education, the role of schools in teacher training and the direction of future research.

Summary Coinfection with HIV adversely impacts every stage of hepatitis C (HCV) infection. Liver damage in HCV infection results from host antiviral responses rather than direct viral pathogenesis. Despite depressed cellular immunity, coinfected patients show accelerated hepatic fibrosis compared with HCV monoinfected patients. This paradox is poorly understood. T‐regulatory (Treg) cells (CD4+ and FOXP3+) are hypothesized to limit hepatic damage in HCV. Our hypothesis was that reduced frequency of hepatic Treg in HIV/HCV coinfection compared with HCV monoinfection may explain poorer outcomes. We quantified FOXP3+, CD4+, CD8+ and CD20+ cells in liver biopsies of 35 male subjects matched by age and ISHAK fibrosis score, 12 HIV monoinfected, 11 HCV monoinfected and 12 HIV/HCV coinfected. Cell counts were performed using indirect immunohistochemical staining and light microscopy. HIV/HCV coinfected subjects had fewer hepatic FOXP3+ (P = 0.031) and CD4+ cells (P = 0.001) than HCV monoinfected subjects. Coinfected subjects had more hepatic CD8+ cells compared with HCV monoinfected (P = 0.023), and a lower ratio of FOXP3+ to CD8+ cells (0.08 vs 0.27, P

The polymerase chain reaction (PCR) was used to amplify a 149 base-pair region of the cytomegalovirus (CMV) genome and a 551 base-pair region of the HIV-1 proviral long terminal repeat (LTR) present in DNA extracted from post-mortem tissue. Multiple tissues (n = 116) obtained from 16 patients which were subjected to PCR were also subjected to cell culture and histopathological analyses. One hundred and seven samples (92%) contained CMV DNA and 66/116 (57%) contained HIV proviral DNA at a level of > or = 10 genomes. Both viruses were detected in 60/116 (51.7%) of samples, with co-infection most frequent in the lung (69%). Cell culture for CMV detected 9.3% of the PCR-positive samples, whilst histology identified CMV inclusions in 15.9% of samples, all of which were CMV PCR-positive. CMV was most frequently detected in adrenal and lung tissues by histology. These results show that co-infection with CMV and HIV is a common occurrence in organs from AIDS patients and provide further evidence for a role of cytomegalovirus in the pathogenesis of AIDS.

We developed an iterative sequential random utility model to investigate the social and environmental determinants of the spatiotemporal decision process of tuna purse-seine fishery fishing effort in the eastern Pacific Ocean. Operations of the fishing gear mark checkpoints in a continuous complex decision-making process. Individual fisher behavior is modeled by identifying diversified choices over decision-space for an entire fishing trip, which allows inclusion of prior and current vessel locations and conditions among the explanatory variables. Among these factors are vessel capacity; departure and arrival port; duration of the fishing trip; daily and cumulative distance travelled, which provides a proxy for operation costs; expected revenue; oceanographic conditions; and tons of fish on board. The model uses a two-step decision process to capture the probability of a vessel choosing a specific fishing region for the first set and the probability of switching to (or staying in) a specific region to fish before returning to its landing port. The model provides a means to anticipate the success of marine resource management, and it can be used to evaluate fleet diversity in fisher behavior, the impact of climate variability, and the stability and resilience of complex coupled human and natural systems.

The screening of a λgt11 library with monoclonal antibodies described here is a relatively uncomplicated procedure, but it requires a little introduction nevertheless. For simplicity, it is assumed that you have in your possession a library that is ready to screen, i.e., either a library bought from a company or a library that you have made. Construction of a λgt11 library is described in Volume 4, Chapter 19 .

X-linked agammaglobulinemia (XLA) is a hereditary defect of B-cell differentiation in man caused by deficiency of Bruton tyrosine kinase (BTK). A three-dimensional model for the BTK kinase domain, based on the core structure of cAMP-dependent protein kinase, was used to interpret the structural basis for disease in eight independent point mutations in patients with XLA. As Arg-525 of BTK has been thought to functionally substitute for a critical lysine residue in protein-serine kinases, the mutation Arg-525-->Gln was studied and found to abrogate the tyrosine kinase activity of BTK. All of the eight mutations (Lys-430-->Glu, Arg-520-->Glu, Arg-525-->Gln, Arg-562-->Pro, Ala-582-->Val, Glu-589-->Gly, Gly-594-->Glu, and Gly-613-->Asp) were located on one face of the BTK kinase domain, indicating structural clustering of functionally important residues.

SUMMARYAntigen-driven responses by T cells from patients with CVID and normal subjects have been assessed. Low-density cells enriched for antigen-presenting dendritic cells were cultured with T cells using a 20-μl hanging drop system, T cells from all subgroups of CVID patients showed markedly reduced responses lo the recall antigens purified protein derivative (PPD) or tetanus toxoid. whereas responses by cells from patients with X-linked agammaglobulinaemia, used as a disease control, were in the normal range. However, primary allo-stimulation of CVID T cells was normal, CVID cells from two patients failed lo respond to stimulation with a neoantigen, an HIV env peptide. under conditions where normal T ceils did respond. These data illustrate a profound defect in antigen-stimulated T cell proliferation in vitro in all groups of CVID patients, but do not distinguish whether the defect is in the presenting cell or in the T lymphocyte. In vitro, germinal centre B cells are thought lo present antigen to primed T cells lo obtain essential signals (e.g. CD40 ligand and IL-2) for B cell survival and progression to immunoglobulin secretion. A failure of antigen-specific T cell function in vivo in CVID would thus not provide the primed T cells needed for B cell rescue, and could be the primary defect leading to the low immunoglobulin production in this condition.

OBJECTIVES--To study the occurrence of mycoplasmas and ureaplasmas in patients with hypogammaglobulinaemia and the relationship of these micro-organisms to septic arthritis. METHODS--Over a period of about 20 years, 53 men and 38 women with hypogammaglobulinaemia, most of whom were less than 50 years old, were examined clinically and microbiologically. Mycoplasmas and ureaplasmas were sought in the throat, urogenital tract and joints by standard cultural methods, although not consistently in the three sites of all patients. RESULTS--Arginine-hydrolysing mycoplasmas and ureaplasmas occurred with similar frequency in the sputum/throat of the hypogammaglobulinaemic patients, but no more often than might be expected in immunocompetent patients. Ureaplasmas, however, dominated in the urogenital tracts of both men and women, being found in 75% of vaginal specimens. Arginine-hydrolysing mycoplasmas occurred two to six times more frequently and ureaplasmas two to three times more frequently in urine specimens from hypogammaglobulinaemic patients than they did in such specimens from sex- and age-matched non-venereal disease, hospital patients or healthy subjects; these differences were statistically significant (p < 0.05). Enhanced mucosal colonisation probably increases the chance of spread to distant sites, such as the joints. Of the 91 patients, 21 (23%) had septic arthritis involving one or more joints. Mycoplasmas and/or ureaplasmas, but not bacteria, were isolated from the joints of eight (38%) of these patients. However, dissemination to joints apparently had not occurred in some despite the opportunity by virtue of mycoplasmal or ureaplasmal colonisation at a mucosal site. Sometimes antibiotic therapy failed clinically, and microbiologically and recommendations for management are outlined. CONCLUSIONS--Hypogammaglobulinaemic patients appear to be more susceptible to colonisation of mucous membranes, especially of the urogenital tract, with mycoplasmas and ureaplasmas than are immunocompetent individuals. These micro-organisms are responsible for about two fifths of the septic arthritides occurring in these patients.

SUMMARY CVID is an acquired disease with low serum immunoglobulins. Patients are classified into three groups on the ability of their B cells to secrete IgM and IgG in vitro in response to IL-2. We have now extended this patient classification to include IgA secretion and to assess whether the patients have IgA+ B cells in the circulation. B cells from almost all of the CVID patients studied were unable to secrete any IgA in vitro, with or without IL-2, although all B cells tested from normal donors showed some spontaneous IgA secretion. Thus, the defect with IgA secretion is more profound than with the secretion of IgM or IgG. Despite this failure to secrete IgA, using flow cytometry techniques all CVID patients tested were found to have IgA+ cells (expressed as a percentage of B cells) within the normal range. This suggests that CVID may involve a defect in the secretion of immunoglobulin isotypes rather than a defect in isotype switching.

Objectives: The objectives of this study were: (i) to describe an outbreak of multidrug-resistant Klebsiella pneumoniae in our population; (ii) to identify the potential source of this outbreak by examining antibiotic resistance trends in urocultures; (iii) to evaluate the contribution of this outbreak to resistance patterns over time in the two commonest Gram-negative blood culture isolates, namely K. pneumoniae and Escherichia coli; and (iv) to assess risk factors for multidrug resistance and the impact of this resistance on mortality and length of stay. Methods: We searched Microbiology and Patient Administration Service databases retrospectively and describe resistance trends in E. coli and K. pneumoniae bloodstream infections (BSIs) in Oxfordshire, UK, over an 11 year period. Results: An outbreak of a multidrug-resistant, CTX-M-15 extended-spectrum b-lactamase (ESBL)-producing K. pneumoniae clone was identified and shown by multilocus sequence typing to belong to a novel sequence type designated ST490. This was associated with a sporadic change in resistance rates in K. pneumoniae BSIs with rates of multidrug resistance (defined as resistance to three or more antibiotic classes) reaching 40%. A case–control study showed prior antibiotic exposure as a risk factor for infection with this organism. During the same time period, rates of ESBL-producing Klebsiella spp. isolated from urocultures increased from 0.5% to almost 6%. By contrast, the rate of multidrug resistance in E. coli rose more steadily from 0% in 2000 to 10% in 2010. Conclusions: Changes in resistance rates may be associated with outbreaks of resistant clones in K. pneumoniae. Changing resistance patterns may affect important health economic issues such as length of stay.

SUMMARY DNA of circulating lymphocytes obtained from 17 patients with ‘common variable’ immunodeficiency (CVID) was tested for the presence of HIV-1 sequences, using a variety of primers complementary to conserved regions of HIV-1 genomes. None of the patients was positive. The DNA from 12 CVID patients was tested for the presence of human herpes virus 6 (HHV-6), using appropriate primers for this virus which is known to remain latent following primary infection in the majority of people during childhood. Similar numbers of patients and normal subjects were positive (about 30%), suggesting that CVID patients are not particularly prone to reactivation of this virus. Despite previous anecdotal reports of an unexplained association between HIV-1 and CVID, we conclude that there is no evidence that this virus is implicated in the pathogenesis of CVID. A role for HHV-6 also seems unlikely.

Blunt trauma patients with pelvic fractures have been shown to have a two-fold to five-fold increased risk of aortic rupture compared with the overall blunt trauma population. A retrospective review was performed to determine whether the relationship between aortic rupture and pelvic fracture could be further delineated using a pelvic fracture classification based on mechanism of injury. Of 4,157 consecutive blunt trauma patients, 371 (8.9%) had pelvic fractures, 34 (0.8%) had ruptured thoracic aortas and 12 had both injuries. When pelvic fractures were classified according to vector of force, 10 of 12 (83%) aortic ruptures occurred in patients with an anterior-posterior compression fracture pattern, an incidence of aortic rupture eight times greater than that of the overall blunt trauma population. There was no increased incidence of aortic rupture among patients with any other pelvic fracture pattern. We conclude that the previously reported association between aortic rupture and pelvic fracture can be further specified to include, predominantly, those patients with an anterior-posterior compression fracture pattern.

SUMMARY Secretion or IgM and IgG in vitro by B cells from patients with common variable immunodeficiency (CVI) has been used to classify the disease into three groups. On stimulation with anti-IgM and IL-2, group A patients' cells fail to secrete IgM or IgG, group B patients' cells secrete no IgG and significantly lower levels of IgM than normal cells, and group C patients' cells produce normal levels of both isotypes, Direct activation of protein kinase C using 12, 13-phorbol dibutyrate and ionomycin followed by IL-2 or IL-4 has been reported to induce immunoglobulin secretion by normal human B cells. We therefore attempted to induce B cells from group A and group B CVI patients to secrete IgM and IgG after direct activation of protein kinase C together with IL-2 or IL-4. The data show that the failure of secretion of immunoglobulin by B cells from CVI patients could not be reversed using this approach. This finding suggests that the activation channel involving protein kinase C in B cells from CVI patients is not involved in the defect in cell differentiation.

We report a patient with common variable immunodeficiency (CVID) who developed an axonal sensorimotor polyneuropathy, a hitherto unreported association to our knowledge. These conditions may be linked at the pathogenetic level, since some CVID patients are prone to the development of autoimmune disease.

A cohort of 111 HIV-infected haemophiliacs has been followed for up to 11 years, during which time 33 patients have been diagnosed with AIDS. Twenty-seven of the cohort developed detectable p24 antigenaemia while remaining free of AIDS. These patients experienced an increased risk of progression to AIDS compared with those patients who were persistently p24-negative (relative risk 7.24; P less than 0.0001, Cox proportional hazards model). The relative risk was reduced to 5.42 (P less than 0.0001) after adjustment for age and cytomegalovirus seropositivity. After adjustment for the patients' declining CD4 lymphocyte count during follow-up, the relative risk fell dramatically to 1.97 and became non-significant (P = 0.2). p24-antigenaemic patients tended to develop AIDS at levels of similar CD4 lymphocyte counts to those who were persistently p24-antigen-negative (median CD4 lymphocyte counts, 70 and 50 x 10(6)/l, respectively). These results suggests that the association between p24 antigenaemia and the rate of progression to AIDS can be explained largely by a more rapid decline in CD4 lymphocyte count among patients with p24 antigenaemia than in those without. The major pathological effects of increased plasma viral load, as detected by the presence or absence of p24 antigenaemia, appear to act via progressive CD4 lymphocyte depletion.

SUMMARY DNA synthesis in response to mitogens has been studied in T cells from nine patients with common variable immunodeficiency (CVI) and seven normal individuals. Five out of the nine patients had cells with subnormal responses to the mitogen phytohaemagglutinin (PHA). As PHA-induced responses are largely mediated through activation of Ca2+-dependent protein kinase C, we studied whether the defective response was still present on direct activation of protein kinase C. This was done using combinations of concentrations of phorbol 12,13,-dibutyrate and the calcium ionophore ionomycin which induced proliferation in normal T cells. We found that in CVI patients with T cells which had normal responses to PHA, responses to phorbol ester and ionomycin were at the same level as in normal T cells. However, with this treatment, in which the linkage between the membrane receptor and protein kinase C is bypassed, the level of DNA synthesis was still depressed in the patient group whose T cells had subnormal responses to PHA. IL-2 failed to restore the DNA synthesis to normal levels when added with the phorbol ester and ionomycin to T cells from one patient in this group. These data suggest that in a group of CVI patients there are defects in T cell activation pathways at or down-stream of protein kinase C.

Summary Three cases of severe and irreversible alopecia occurring in patients with common variable immunodeficiency are described. In all three cases, hair loss developed after the diagnosis of immune deficiency; one of the patients also had extensive vitiligo. A fourth patient had vitiligo in the absence of alopecia. No change in the alopecia or vitiligo was noted in any patient as a result of immunoglobulin replacement therapy.

Anti-idiotypic antibodies to anti-CD4 monoclonal antibodies (MAbs) have been reported to bind to the human immunodeficiency virus (HIV) envelope glycoprotein gp120. To establish whether HIV-infected patients can mount an anti-idiotypic response to murine MAb, four individuals with symptoms of AIDS-related complex (ARC) were immunized over 10 weeks with six intramuscular injections of anti-Leu 3a (1 mg). Despite their immunocompromised state, all patients made anti-constant region and anti-idiotypic antibodies, although the amplitude of the responses varied between individuals. No significant toxic or allergic reactions were seen, and there were no changes in clinical status during the 6 months after immunization. No increase in serum HIV-neutralization titers was seen, and purified anti-idiotypic antibodies did not bind gp120.

The role of leucocyte integrins in phagocyte function has been studied by comparing normal neutrophils with those from a patient with partial leucocyte adhesion deficiency (LAD), in whom the levels of CD11b and CD11c were 10% of controls, whereas CD11a levels were normal. Unstimulated LAD neutrophils exhibited defective adhesion to plastic (4·4 ± 1·5% cf. 14·4 ± 3·8% in controls), but not to human umbilical vein endothelial cells (HUVECs). The adhesion to HUVECs could be further upregulated by granulocyte‐macrophage colony stimulating factor (GM‐CSF), but not by 12‐0‐tetradecanoylphorbol 13‐acetate (TPA) which, in normal cells, is a more potent ‘pro‐adhesive agonist’. The normal neutrophil‐endothelial interaction induced by GM‐ CSF in LAD neutrophils was confirmed in vivo when administration of GM‐CSF resulted in rapid phagocyte marginatum. Neutrophil migration and phagocytosis/killing were defective in LAD neutrophils, and some improvement in phagocytosis/killing was seen following in vivo administration of GM‐CSF. These studies illustrate that the degree to which the leucocyte integrins mediate adherence‐related phagocyte functions varies not only with the particular function, but also with the conditions of stimulation. High levels of CD11b and CD11c expression appear not to be required for unstimulated or GM‐CSF‐stimulated neutrophil‐endothelial interactions, either In vitro or in vivo. Other neutrophil functions, on the other hand, such as migration and phagocytosis/killing are much more dependent on the leucocyte integrins. Copyright © 1991, Wiley Blackwell. All rights reserved

Genetic defects in purine metabolism are associated with severe immunodeficiency. Adenosine deaminase deficiency impairs the function of both B- and T-lymphocytes whereas in purine nucleoside (inosine) phosphorylase deficiency there is more severe impairment of T-lymphocyte functions than of B-lymphocyte functions. The relative unimportance of the salvage pathway catalysed by hypoxanthine-guanine phosphoribosyltransferase is shown by the normal responses of T-lymphocytes from patients with the Lesch-Nyhan syndrome to antigenic and mitogenic stimulation. A mild deficiency of B-lymphocyte function is found in these patients. Agents inhibiting the de novo pathway of purine synthesis, including azaserine, 6-mercaptopurine and azathioprine in low doses, block the responses of normal human lymphocytes to mitogenic stimulation. These observations emphasize the importance of the de novo pathway of purine synthesis in lymphocyte responses to antigenic and mitogenic stimulation. There is considerable heterogeneity in the amount of labelled uridine incorporated into human and rat lymphocytes. This does not appear to reflect only a difference between T- and B-lymphocytes

The activity of the lymphocyte ectoenzyme 5'-nucleotidase is very low in the majority of patients with primary 'common variable' hypogammaglobulinaemia. In order to test whether this can be explained by lymphocyte subpopulation deficiencies we measured 5'-nucleotidase activity, using both biochemical and histochemical techniques, in purified T and B cells from patients and healthy subjects. Purified B cells from normal subjects have about four times the activity of T cells. This explains why the levels of lymphocyte 5'-nucleotidase activity are at the lower limit of the normal range in patients with X-linked hypogammaglobulinaemia who lack B cells. The low levels in the 'common variable' group can be explained by low activity in their T lymphocytes associated with either low activity in their B cells or depletion of B cells. The finding that inhibition of the enzyme does not interfere with in vitro lymphocyte transformation or immunoglobulin production in normal subjects indicates that the enzyme deficiency is not directly responsible for the hypogammaglobulinaemia. These and other studies suggest that this enzyme appears on lymphocytes at a certain stage of development and that both T and B lymphocytes in some patients with 'common variable' hypogammaglobulinaemia are developmentally immature.