CIK1: a developmentally regulated spindle pole body-associated protein important for microtubule functions in Saccharomyces cerevisiae.

A genetic screen was devised to identify genes important for spindle pole body (SPB) and/or microtubule functions. Four mutants defective in both nuclear fusion (karyogamy) and chromosome maintenance were isolated; these mutants termed cik (for chromosome instability and karyogamy) define three complementation groups. The CIK1 gene was cloned and characterized. Sequence analysis of the CIK1 gene predicts that the CIK1 protein is 594 amino acids in length and possesses a central 300-amino-acid coiled-coil domain. Two different CIK1-beta-galactosidase fusions localize to the SPB region in vegetative cells, and antibodies against the authentic protein detect CIK1 in the SPB region of alpha-factor-treated cells. Evaluation of cells deleted for CIK1 (cik1-delta) indicates that CIK1 is important for the formation or maintenance of a spindle apparatus. Longer and slightly more microtubule bundles are visible in cik1-delta strains than in wild type. Thus, CIK1 encodes a SPB-associated component that is important for proper organization of microtubule arrays and the establishment of a spindle during vegetative growth. Furthermore, the CIK1 gene is essential for karyogamy, and the level of the CIK1 protein at the SPB appears to be dramatically induced by alpha-factor treatment. These results indicate that molecular changes occur at the microtubule-organizing center (MTOC) as the yeast cell prepares for karyogamy and imply that specialization of the MTOC or its associated microtubules occurs in preparation for particular microtubule functions in the yeast life cycle.     

LAPSER1/LZTS2: a pluripotent tumor suppressor linked to the inhibition of katanin-mediated microtubule severing

Human chromosome region 10q23-24 is one of the most frequently found regions that show loss of heterozygosity in prostate cancers. A candidate tumor suppressor LAPSER1/LZTS2 (LAPSER1) is located in 10q24.3 that has been reported to be deleted as frequently as the neighboring PTEN locus. We previously reported that LAPSER1 binds p80 katanin, a subunit of the katanin heterodimer. In this report, we show that the LAPSER1 C terminal domain inhibits katanin-mediated microtubule severing in vitro and we detected this inhibition at centrosomes by tracing the nucleated de novo, severed, and transported microtubules in cells. This functional association is also supported by the intracellular localization. Centrosomal localization of LAPSER1 was independent of microtubules and was preferential to mother centrioles. In primary cultured neurons, LAPSER1 also colocalizes with p80 katanin. LAPSER1 alters cell proliferation by regulating cytokinesis. As subcellular mechanisms that underlie the tumor suppressive activity, exogenous LAPSER1 expression inhibited central spindle formation by abrogating microtubule transportation and a similar mode of inhibition was found in axogenesis. Katanin knockdown and dominant negative inhibitor of katanin provided similar phenotypes. Prophase LAPSER1 inhibited centrosomal gamma-tubulin accumulation, which resulted in retardation of mitotic entry. Furthermore, interphase inhibition of katanin by LAPSER1 expression resulted in prevention of cell motility that was accompanied by the increased acetylated microtubules. LAPSER1 knockdown increased cell migration that was inhibited by the expression of ninein, a microtubule release inhibitor. These results indicate that microtubule severing at centrosomes is a novel tumor-associated molecular subcircuit in cells, in which LAPSER1 is a regulator.     

Cdk1-Clb4 controls the interaction of astral microtubule plus ends with subdomains of the daughter cell cortex

As in many polarized cells, spindle alignment in yeast is essential and cell cycle regulated. A key step that governs spindle alignment is the selective binding of the Kar9 protein to only one of the two spindle pole bodies (SPBs). It has been suggested that cyclin-dependent kinase Cdc28, in complex with cyclin Clb4, associates only with the SPB in the mother cell and so prevents Kar9 binding to this SPB. However, here we show that the nonoverexpressed Clb4 associates with the budward-directed SPB through Kar9. Cdc28-Clb4 then uses Kar9 as a carrier to move from this SPB to the plus ends of astral microtubules, where Cdc28-Clb4 regulates the interactions between microtubule ends and subdomains of the bud cortex. In the absence of Cdc28-Clb4 activity (G1/S phase), astral microtubules interact with the bud tip in a manner dependent on actin, Myo2, and Kar9. Coincidentally with reaching the bud cortex in S phase, Cdc28-Clb4 facilitates the dissociation of the microtubule bud tip interaction and their capture by the bud neck. This transition prevents the preanaphase spindle from becoming prematurely pulled into the bud. Thus, Cdc28-Clb4 facilitates spindle alignment by regulating the interaction of astral microtubules with subdomains of the bud cortex.     

Cytokine and chemokine expression in the skin from patients with maculopapular exanthema to drugs

Background:  Maculopapular exanthema (MPE) is the most frequent clinical manifestation of nonimmediate allergic reactions to drugs and T helper 1 (Th1) cytokines and CD4⁺ T cells have been shown to play an important role in its pathogenesis. We assessed the role of cytokines and chemokines and their receptors in the pathogenesis of MPE.
Methods:  We evaluated skin biopsies and peripheral CD4⁺ and CD8⁺ T cells from 27 patients during the acute phase of the reaction and 26 exposed controls. Semiquantitative real-time PCR was performed to determine the expression of cytokines and chemokines and their receptors and immunohistochemistry was used to determine the same chemokines and their receptor proteins in skin.
Results:  There was a high expression of the Th1 cytokines interferon-γ ( P  = 0.006) and tumor necrosis factor-α ( P  = 0.022) in skin and CD4⁺ T cells ( P  = 0.007 and P  = 0.005, respectively); and of the Th1 chemokines CXCL9 ( P  = 0.005) and CXCL10 ( P  = 0.028) in the skin, while their receptor CXCR3 was increased in skin ( P  = 0.006) and CD4⁺ T cells ( P  = 0.03). Homing chemokine receptors were also increased: CCR6 in skin ( P  = 0.026) and CD4⁺ T cells ( P  = 0.016), and CCR10 only in CD4⁺ T cells ( P  = 0.016), as well as their ligands, CCL20 and CCL27, in skin alone. Immunohistochemistry confirmed these results.
Conclusions:  These data show significant differences in the expression of chemokines and chemokine receptors, related with a Th1 profile, in both skin biopsies and peripheral CD4⁺ T cells in patients with drug-induced MPE.     

The Single-Shot GnRH Immunocontraceptive Vaccine (GonaCon™) in White-Tailed Deer: Comparison of Several GnRH Preparations

Problem  An effective, single-injection, multi-year, GnRH contraceptive agent is needed to control reproduction in overabundant white-tailed deer populations.
Method of study  Two GnRH conjugates, GonaCon^™ (GnRH–KLH) and GonaCon-B^™ (GnRH–blue protein), were prepared in emulsion form as one-injection and two-injection immunocontraceptive vaccine formulations. In addition, the GnRH–KLH protein conjugate was lyophilized and suspended in AdjuVac^™ adjuvant to produce a fifth vaccine formulation. Each formulation was administered to a group of five captive adult female white-tailed deer. Reproductive performance of treated female deer was monitored for 5 years to determine the comparative efficacy of the various treatments.
Results  The longevity of the contraceptive response (2–5 years) was strongly influenced by the design of the conjugate antigen, the adjuvant used, and the delivery form of the vaccine.
Conclusion  One-injection and two-injection formulations of GonaCon^™ and GonaCon-B^™ produced multi-year contraception in adult female white-tailed deer. GonaCon-B^™ provided a longer lasting contraceptive effect.     

Confirmation of the novel association at the BTNL2 locus with ulcerative colitis

Linkage in families and association in population case–control investigations have clearly shown that genes within the major histocompatibility complex region on chromosome 6p are relevant to the susceptibility and pathogenesis of ulcerative colitis (UC) and Crohn's disease. However, identifying the causative variants by fine mapping has not been conclusive. In this study using 58 single nucleotide polymorphisms (SNPs) with 616 UC cases, there was significant association with SNP rs2294881 of the (butyrophilin-like 2) BTNL2 gene with odds ratio (OR) = 2.80, confidence interval (CI) = 1.62–4.84 and P  = 5.69 × 10⁻⁴ ( P _Bonferroni = 3.3 × 10⁻²) and replication of SNP rs9268480. The missense SNP rs2076523 (K196E) showed novel association with a subset of UC cases with colectomy ( n  = 126), OR = 0.25, CI = 0.11–0.58 and P  = 4.42 × 10⁻⁴ ( P _Bonferroni = 2.56 × 10⁻²). These three associated variants within the BTNL2 gene were neither in linkage disequilibrium with each other nor correlated with the SNPs tagging the human leukocyte antigen (HLA)-DRB1*1502 and HLA-DRB1*0301 alleles.     

Timed Sexual Intercourse Facilitates the Recruitment of Uterine CD56bright Natural Killer Cells in Women with Infertility

Problem  The aim of this study was to investigate the influence of sexual intercourse on uterine NK cell subsets.
Method of study  Mid-secretory endometrial samples obtained from 56 women were submitted for flow cytometric analysis. Basal body temperature was used to determine the day of ovulation. A total of 27 women had sexual intercourse before ovulation (pre-ovulation group) and eight women had only after ovulation (post-ovulation group) without any contraceptive devices. A total of 21 women did not have sexual intercourse during the experimental cycle (abstinence group). Endometrial NK cells were analyzed for the expression of CD16 and CD56 using 3-color flow cytometry.
Results  CD16⁻/CD56^bright cells were markedly increased in the pre-ovulation group as compared with that of the post-ovulation group ( P  < 0.01) and the abstinence group ( P  < 0.01). CD16⁺/CD56^dim cells were significantly decreased in the pre-ovulation group as compared with that of the post-ovulation group ( P  < 0.01) and the abstinence group ( P  < 0.05).
Conclusion  It is suggested that seminal plasma participates in the recruitment of CD56^bright NK cells into endometrium.     

Contribution of dynein light intermediate and intermediate chains to subcellular localization of the dynein–dynactin motor complex in Schizosaccharomyces pombe

In fission yeast Schizosaccharomyces pombe, cytoplasmic dynein drives oscillatory nuclear movement during meiotic prophase, which may facilitate pairing of homologous chromosomes. Here, we report the identification of a dynein light intermediate chain (LIC) in fission yeast, termed Dli1p, and show that Dli1p and dynein intermediate chain (IC) Dic1p are essential for the appropriate subcellular localization and proper function of dynein during meiotic prophase. Expression of both the dli1 and dic1 genes was observed only in cells undergoing meiosis. Dli1p interacted and colocalized with dynein heavy chain Dhc1p. The subcellular localization of Dli1p was dependent on Dhc1p, and vice versa. The Dhc1p–Dli1p subcomplex could localize to the spindle pole body (SPB) with no aid of Dic1p and dynactin subunit Ssm4p, but its localization to microtubules was dependent on these two proteins. Dic1p localized to microtubules depending on Ssm4p, but not on Dhc1p and Dli1p. Its localization to the SPB, however, was dependent on Dhc1p and Dli1p. Localization of Ssm4p to the SPB was largely dependent on Dhc1p, Dli1p and Dic1p. Thus, Dli1p and Dic1p contribute differently in localizing the dynein–dynactin motor complex to organelles, providing novel insight into the in vivo function of dynein subunits in fission yeast.     

Bcl-10 protein highly correlates with the expression of phosphorylated p65 NF-κB in peripheral T-cell lymphomas and is associated with clinical outcome

Aims:  In T cells, protein kinase C (PKC) θ plays a major role in T-cell receptor (TCR)-mediated activation of a novel nuclear factor (NF)-κB pathway that involves phosphorylation of p65 at serine 536 (Pp65^Ser536). Bcl-10 acts along the same pathway downstream of PKC θ to activate NF-κB. The aim was to investigate the relationship between the expression of PKC θ, Bcl-10 and P-p65^Ser536 proteins and their prognostic significance in peripheral T-cell lymphomas (PTCLs).
Methods and results:  Paraffin-embedded tissues from 30 patients with PTCLs treated with curative intention were evaluated retrospectively. Expression of PKC θ, Bcl-10 and P-p65^Ser536 proteins was assessed using immunohistochemistry. Expression of PKC θ was detected in 22 of 30 cases (73%), Bcl-10 in 20 of 30 (67%) and P-p65^Ser536 in 21 of 30 (70%). Bcl-10+ tumours were associated with PKC θ (18 of 22) ( P  < 0.0001) and Pp65Ser536 (19 of 21) expression ( P  < 0.0001). Patients with Bcl-10+ or P-p65^Ser536+ tumours fared better, with a 5-year overall survival of 48 and 45%, respectively, versus 0% for negative tumours ( P  = 0.029 and P  = 0.04, respectively).
Conclusions:  Bcl-10 is expressed in PTCLs, correlates with PKC θ and Pp65^Ser536 expression and seems to be associated with better survival.     

Selectivity and interactions of Ba2+ and Cs+ with wild-type and mutant TASK1 K+ channels expressed in Xenopus oocytes

The acid-sensitive K⁺ channel, TASK1 is a member of the K⁺-selective tandem-pore domain (K2P) channel family. Like many of the K2P channels, TASK1 is relatively insensitive to conventional channel blockers such as Ba²⁺. In this paper we report the impact of mutating the pore-neighbouring histidine residues, which are involved in pH sensing, on the sensitivity to blockade by Ba²⁺ and Cs⁺; additionally we compare the selectivity of these channels to extracellular K⁺, Na⁺ and Rb⁺. H98D and H98N mutants showed reduced selectivity for K⁺ over both Na⁺ and Rb⁺, and significant permeation of Rb⁺. This enhanced permeability must reflect changes in the structure or flexibility of the selectivity filter. Blockade by Ba²⁺ and Cs⁺ was voltage-dependent, indicating that both ions block within the pore. In 100 m m K⁺, the K _D at 0 mV for Ba²⁺ was 36 ± 10 m m  ( n = 6)  , whilst for Cs⁺ it was 20 ± 6.0 m m  ( n = 5)  . H98D was more sensitive to Ba²⁺ than the wild-type (WT); in addition, the site at which Ba²⁺ appears to bind was altered (WT: δ, 0.64 ± 0.16, n = 6; H98D: δ, 0.16 ± 0.03, n = 5, statistically different from WT; H98N: δ, 0.58 ± 0.09, not statistically different from WT). Thus, the pore-neighbouring residue H98 contributes not only to the pH sensitivity of TASK1, but also to the structure of the conduction pathway.     

Distribution of immunocompetent cells in decidua of controlled and uncontrolled (choriocarcinoma/hydatidiform mole) trophoblast invasion

Problem:  Pregnancy has been considered as a model of successfully controlled tissue invasion where trophoblast cells infiltrate the maternal decidua without being rejected or without destroying the tissue. In choriocarcinoma (CC) and hydatidiform mole (HM), a dysregulation of invasive (malignant/benign) trophoblast cells is present. Immunocompetent cells (IC) are known to be involved in rejection pathways of malignant cells and can also be identified in early pregnancy decidua. The aim of the present study was to identify the phenotype of IC in decidua of women with normal pregnancy (NP), CC and HM.
Methods:  Immunocompetent cells were detected by immunohistochemistry in decidual tissue from first trimester NP ( n  = 10), CC ( n  = 12) and HM ( n  = 11) using antibodies against CD8⁺, CD3⁺, CD56⁺, CD68⁺ cell surface markers and mast cell tryptase (MCT). A scaled eye piece was used for cell counting to obtain semiquantitative results. Statistical analysis was performed using Wilcoxon rank/Mann–Whitney tests.
Results:  We observed a significantly increased number of lymphocytes positive for CD8, CD3 and MCT positive granulocytes in CC and HM compared with the samples from NP (all P  ≤ 0.001). Lymphocytes positive for natural killer (NK) cell marker CD56 were significantly decreased in CC and HM versus NP ( P  ≤ 0.001). The number of CD68 positive cells (macrophages) were not significantly different among the tissue pools.
Conclusion:  The increase of CD8/CD3 T cells and mast cells in CC and HM and the decrease of CD56 cells, compared with NP, suggests the necessity of a balance between T and NK cells in controlling trophoblast invasion.     

Use of an automated DNA analysis system (DARAS®) for sequence-specific recognition of Neisseria meningitidis DNA

Objectives To combine use of the polymerase chain reaction (PCR) for rapid diagnosis of meningococcal meningitis with a novel automated detection system for sequence-specific recognition of PCR products.
Methods   DNA was extracted from cerebrospinal fluid (CSF) by a quick boil-lysis method, followed by PCR with primers specific for Neisseria meningitidis . Sequence-specific recognition of N. meningitidis DNA was performed with an automated DNA analysis system (DARAS^®) and the data were compared with results following agarose gel electrophoresis or conventional microbiological culture.
Results   The DARAS^® system had a sensitive detection limit of 10² meningococci/mL with spiked samples, compared with a detection limit of 10⁴ meningococci/mL following agarose gel electrophoresis. When the system was used to examine 74 CSF samples, the 19 CSF samples positive for N. meningitidis by conventional microbiological methods were also all positive in the DARAS^® system and the 55 samples negative by DARAS^® for meningococci were also negative by conventional microbiological methods.
Conclusion The sensitivity and specificity of the DARAS^® system makes it a useful tool for the diagnosis of meningococcal meningitis. The system is user-friendly, requires minimal hands-on time and generates data in an informative numerical format.     

The functional insufficiency of human CD4+CD25 high T-regulatory cells in allergic asthma is subjected to TNF-alpha modulation

Background:  Natural CD4⁺CD25^highFoxp3⁺ regulatory T (nTreg) cells are important in maintaining immunologic tolerance, but their role in the pathogenesis of allergic asthma is unclear. We studied the function of nTreg cells in allergic asthmatic children and assessed the factors which may relate to the functional insufficiency of nTreg cells.
Methods:  The percentage of CD4⁺CD25^high Treg cells, the expression of Foxp3, and the cell-induced suppressive activity of nTreg cells isolated from nonatopic controls, allergic asthmatics, and allergen-specific immunotherapy (AIT)-treated asthmatic patients were studied.
Results:  Although the percentage of nTreg in peripheral blood mononuclear cells was increased, the expression of Foxp3 and its cell-induced suppressive activity were significantly lower in Dermatophagoides pteronyssinus (Der p)-sensitive asthmatic children when compared to nonatopic controls. In contrast, the expression of Foxp3 and the functional activity of nTreg cells were reversed in allergic asthmatics who received AIT. The addition of recombinant tumor necrosis factor (TNF)-α directly downregulated Foxp3 expression and abrogated the cell-induced suppressive function of Treg cells. The anti-TNF-α reagent, etanercept, restored the functional activity and Foxp3 expression of CD4⁺CD25^high Treg derived from allergic asthmatics.
Conclusions:  The functional insufficiency of nTreg cells in patients with allergic asthma may be related to the enhanced production of TNF-α and its effect on the Foxp3 expression. These results may explain, in part, the effectiveness of anti-TNF-α therapy in the treatment of allergic asthma.     

Deletion of RNQ1 gene reveals novel functional relationship between divergently transcribed Bik1p/CLIP-170 and Sfi1p in spindle pole body separation

Spindle pole body (SPB; the microtubule organizing center in yeast) duplication is essential to form a bipolar spindle. The duplicated SPBs must then separate and migrate to opposite sides of the nucleus. We identified a novel functional relationship in SPB separation between the microtubule stabilizing protein Bik1p/CLIP-170 and the SPB half-bridge protein Sfi1p. A genetic interaction between BIK1 and SFI1 was discovered in a synthetic lethal screen using a strain deficient in the prion protein gene RNQ1. RNQ1 deletion reduced expression from the divergently transcribed BIK1, allowing us to identify genetic interactors with bik1. The sfi1-1 bik1 synthetic lethality was suppressed by over-expression of CIK1, KAR1, and PPH21. Genetic analysis indicated that the sfi1-1 bik1 synthetic lethality was unlikely related to the function of Bik1p in the dynein pathway or to defects in spindle position. Furthermore, a sfi1-1 Δkip2 mutant was viable, suggesting that the Bik1p pool at the cytoplasmic microtubule plus-ends may not be required in sfi1-1. Microscopic examination indicated the sfi1-1 mutant was delayed in SPB duplication, SPB separation, or spindle elongation and the sfi-1 Δbik1 double mutant arrested with duplicated but unseparated SPBs. These results suggest that Bik1p has a previously uncharacterized function in the separation of duplicated SPBs.     

Tumor Necrosis Factor-α-Associated Mechanisms Affecting the Embryonic Response to Cyclophosphamide

Problem  We have previously shown that TNF-α^−/− embryos are more sensitive to the exposure to cyclophosphamide (CP) compared with TNF-α^+/+ embryos; however, the underlying mechanisms are not fully understood. Thus, in our present study, we tried to identify those molecules that might be responsible for the protective effect of the cytokine.
Method of study  CP-treated TNF-α^−/− and TNF-α^+/+ embryos were analyzed for changes in apoptosis by TUNEL and flow cytometry, while cell proliferation was analyzed by BrdU incorporation. The expression of Bax, bcl-2, p53, the p65 subunit of NF-κB and IκBα was assessed by Western blotting and immunohistochemistry.
Results  CP-treated TNF-α^−/− embryos exhibited a more profound decrease in their weight, which was accompanied by an earlier appearance of cellular damage and apoptotic cells and an earlier decrease in cell proliferation in the embryonic brain compared with TNF-α^+/+ embryos. Also, an increased percentage of Bax-positive cells and a decreased percentage of bcl-2-positive cells were detected in TNF-α^−/− embryos 48 hr after exposure, which were accompanied by a decreased percentage of p53-positive cells.
Conclusion  Our data implicate TNF-α to be involved in the protection of the embryo against CP teratogenicity, possibly via alteration in Bax, bcl-2 or p53 expression.     

CRAC channels and Ca2+ signaling in mast cells

Summary:  Mast cells are integral members of the immune system. Upon activation by a rise in cytoplasmic Ca²⁺, they release a battery of paracrine signals, chemokines, and cytokines, which help sculpt the subsequent immune response. Ca²⁺ entry through store-operated Ca²⁺ release-activated Ca²⁺ (CRAC) channels in the plasma membrane is central for driving most of these responses. The molecular basis of the CRAC channel has been identified, with Orai1 forming the channel pore. Recent work has revealed that a range of mast cell responses are activated by spatially restricted Ca²⁺ signals just below the plasma membrane. These Ca²⁺ microdomains can activate cytosolic enzymes, leading to the generation of intracellular messengers as well as proinflammatory molecules like LTC₄. In this review, we describe key features of CRAC channels in mast cells, how they generate local Ca²⁺ signals, and how the cell can decode these restricted signals to generate a raft of responses.     

ORAI1 and STIM1 deficiency in human and mice: roles of store-operated Ca2+ entry in the immune system and beyond

Summary:  Store-operated Ca²⁺ entry (SOCE) is a mechanism used by many cells types including lymphocytes and other immune cells to increase intracellular Ca²⁺ concentrations to initiate signal transduction. Activation of immunoreceptors such as the T-cell receptor, B-cell receptor, or Fc receptors results in the release of Ca²⁺ ions from endoplasmic reticulum (ER) Ca²⁺ stores and subsequent activation of plasma membrane Ca²⁺ channels such as the well-characterized Ca²⁺ release-activated Ca²⁺ (CRAC) channel. Two genes have been identified that are essential for SOCE: ORAI1 as the pore-forming subunit of the CRAC channel in the plasma membrane and stromal interaction molecule-1 (STIM1) sensing the ER Ca²⁺ concentration and activating ORAI1-CRAC channels. Intense efforts in the past several years have focused on understanding the molecular mechanism of SOCE and the role it plays for cell functions in vitro and in vivo . A number of transgenic mouse models have been generated to investigate the role of ORAI1 and STIM1 in immunity. In addition, mutations in ORAI1 and STIM1 identified in immunodeficient patients provide valuable insight into the role of both genes and SOCE. This review focuses on the role of ORAI1 and STIM1 in vivo , discussing the phenotypes of ORAI1- and STIM1-deficient human patients and mice.     

A CONTRIBUTION TO THE HEREDITY OF THE P.T.C. TASTE CHARACTER BASED ON A STUDY OF 845 SIB-PAIRS

1. 128 sibships comprising 489 sibs and 845 sib-pairs belonging to the Rárhi Bráhmin community of West Bengal have been studied for p.t.c . taste thresholds by the serial dilution method with a final sorting test.
2. Expectations on the basis of (A) the hypothesis of recessive inheritance of the 'non-taster' phenotype and (B) the hypothesis of chance combination of pairs without any influence of heredity have been compared with the observed data of sib-pairs.
3. Neither of the two hypotheses shows a satisfactory agreement (by the x² test) with the entire mass of observed data. The hypothesis (A), however, appears to be a much closer approach (x²= 17·5 and 20·55, 2 d.f.) to the facts than the hypothesis (B) which yields much higher x² values (x²= 87·11 and 86·93, 2 d.f.).
4. The extreme 'tasters' and 'non-tasters' when separated from the intermediate phenotypes show a very good agreement (x²= 4·340, 3 d.f.) with the hypothesis (A), but a wide divergence (x²= 75·892, 3 d.f.) from the hypothesis (B).
5. The intermediate 'tasters' and 'non-tasters', however, indicate merely a slightly nearer approach (x²= 18·45, 3 d.f.) to hypothesis (B) than to hypothesis (A) (x²= 26·69, 3 d.f.)
The author records his thanks to Dr N. Datta-Majumder, the Director, Department of Anthropology for providing the facilities for the work and to Dr E. C. Biichi, the Superintending Anthropologist for useful discussions. Thanks are also due to Sm. Lalita Ghosh for her sincere assistance.     

IL-12p40 is essential for the down-regulation of airway hyperresponsiveness in a mouse model of bronchial asthma with prolonged antigen exposure

Background We previously reported a mouse model of bronchial asthma showing eosinophilic inflammation, but not airway hyperresponsiveness (AHR), after prolonged antigen exposure. This model showed an increase of IL-12 in the lung.
Objective The aim of this study was to investigate the role of IL-12p40 in a murine asthma model with prolonged antigen exposures.
Methods An ovalbumin (OVA)-induced asthma model was first established in wild-type (WT) and IL-12p40-deficient (IL-12p40^−/−) mice. Both strains of mice were further exposed to either OVA (prolonged exposure group) or phosphate-buffered saline (positive control group) 3 days per week for 3 weeks. During week 4, both groups of mice were given a final challenge with OVA.
Results Prolonged antigen exposures resulted in marked suppression of airway eosinophilia in both WT and IL-12p40^−/− mice. However, AHR persisted in IL-12p40^−/− but not in WT mice. There were no significant differences of IL-5, IL-13 or IFN-γ levels in bronchoalveolar lavage fluid between WT and IL-12p40^−/− mice. The hydroxyproline content of the lung and peribronchial fibrosis were, however, significantly increased in IL-12p40^−/− mice.
Conclusion The results suggest that endogenous IL-12p40 is essential for inhibition of AHR and peribronchial fibrosis, but not eosinophilic inflammation, in a murine asthma model with prolonged antigen exposures.