Clinical evaluation of Vatari guggulu, Maharasnadi kwatha and Narayan taila in the management of osteoarthritis knee

BACKGROUND

In present era, pharmacological, bio-chemical and surgical interventions are not success remedy for Osteoarthritis (OA). Ayurveda and other complementary medicine have medication for OA.

OBJECTIVES

The main aim of the study was to assess the efficacy and safety of therapeutic combination of Vatari guggulu along with Maharasnadi kwatha and Narayan taila with gentle massage for 15 min daily up to 12 weeks on affected knee joint pain assessed on Visual analogue scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC).

MATERIALS AND METHODS

It was an open label, multicentre, prospective, clinical study conducted on 142 patients of OA Knee. Vatari guggulu 500 mg thrice in a day along with Maharasnadi kwatha 20 ml with equal amount of water twice daily and Narayan taila 20 ml twice in a day for external application with gentle massage for 15 min up to 12 weeks were used to all the study participants.

RESULTS

VAS, WOMAC score and clinical symptoms were reduced significantly from baseline to end of the treatment (P < 0.001).

CONCLUSIONS

The study provides good evidence in support of the efficacy and safety of the Vatari guggulu along with Maharasnadi kwatha and Narayan taila in the management of Osteoarthritis knee.

Physiotherapy management of cystic fibrosis

For many years physiotherapy for cystic fibrosis (CF) was synonymous with a daily routine of postural drainage and percussion. Improved longevity and a desire for independence, together with a clearer understanding of the pathophysiology of the disease, has led to the development of many airway clearance techniques. The contribution of ‘chest’ physiotherapy remained unchallenged until recent times when lack of robust evidence and the presentation of asymptomic infants and adults led some physiotherapists to question this traditional approach. As survival increases into the fourth and fifth decade unique complications have evolved and physiotherapy management is challenged with nonrespiratory aspects of treatment. This review will consider the evidence for, and current practice of airway clearance, the value of exercise and the emerging problems of musculoskeletal complications and incontinence.

Physiotherapy in cystic fibrosis: optimising techniques to improve outcomes

Optimisation of physiotherapy techniques to improve outcomes is an area of cystic fibrosis (CF) care, which has developed considerably over the last two decades. With the introduction of newborn screening and an increase in median life expectancy, the management of individuals with CF has needed to adapt to a more dynamic and individualised approach. It is essential that CF physiotherapy management reflects the needs of a changing cohort of paediatric CF patients and it is no longer justifiable to adopt a 'blanket' prescriptive approach to care. The areas of physiotherapy management which are reviewed and discussed in this paper include inhalation therapy, airway clearance techniques, the management of newborn screened infants, physical activity and exercise.

Growth in children with cystic fibrosis-related diabetes

Cystic fibrosis-related diabetes (CFRD) is associated with a shortened life expectancy and greater deterioration in lung function than in CF patients with normal glucose metabolism. There are few published data on how CFRD affects growth in childhood. We carried out a retrospective case controlled study of growth and lung function in 34 children with CFRD attending three specialist centers in London. We found that for the 2 years leading to CFRD diagnosis (at a mean age of 13.1 years), the mean height velocity was significantly less compared to controls: 4.9 (standard deviation-SD 1.6) cm/year vs. 6.0 (SD 1.9) cm/year (P = 0.005). For the 2 years following diagnosis, height velocity remained significantly lower (3.4 (SD 2.2) cm/year vs. 4.4 (SD 2.2) cm/year, P = 0.02). Mean FEV(1) was reduced prior to diagnosis and at diagnosis, but was similar to controls 2 years after diagnosis. This study highlights the compromise in height velocity and lung function that occurs prior to diagnosis of CFRD in children with CF, and a reduction in height velocity should be considered an indicator of impaired glucose metabolism. It would be useful to know whether early treatment with insulin can help promote catch up growth.

Finding consensus on the physiotherapy management of asymptomatic infants with cystic fibrosis

BACKGROUND

Babies with cystic fibrosis diagnosed by neonatal screening often display no overt signs of respiratory disease. The role of traditional routine daily chest physiotherapy in this particular group of babies is unclear and has generated considerable international debate. There is currently no evidence addressing this issue and present circumstances preclude a rigorous trial in the UK. This study aimed to provide expert consensus regarding the physiotherapy management of asymptomatic infants with CF.

METHOD

A Delphi consensus method was used to gather and refine expert opinions of senior paediatric physiotherapists in the UK. Agreement was sought on 16 statements reflecting aspects of physiotherapy management in 'asymptomatic' babies with cystic fibrosis.

RESULTS

Twenty-five senior paediatric physiotherapists from Specialist CF Centres throughout the UK participated in the study. Consensus was high amongst the respondents for 15 of the 16 statements. One statement failed to reach consensus. This related to the question of not routinely initiating a daily chest physiotherapy regimen in apparently healthy babies. Due to the lack of consensus an amendment to this statement was made, to allow a more flexible approach, where physiotherapists would not be obliged to initiate routine daily treatment in asymptomatic babies with CF, if they felt other another approach was justified.

CONCLUSION

There was high consensus of opinion amongst senior physiotherapists in the UK on most aspects of the physiotherapy management of babies with CF. Consensus could not be achieved on whether routine daily chest physiotherapy is necessary in 'asymptomatic' babies. An agreed amendment to the original statement allows professionals to modify or change traditional practice with the sanction of their senior colleagues. The results of this process will be used by the Association of Chartered Physiotherapists in Cystic Fibrosis to form the basis of national clinical guidelines.

Chest physiotherapy during anesthesia for children with cystic fibrosis: effects on respiratory function

BACKGROUND

Physiotherapists sometimes use elective surgical procedures for children with cystic fibrosis as an opportunity to perform physiotherapy treatments during anesthesia. These treatments theoretically facilitate direct endotracheal airway clearance and compensate for any post-operative respiratory deterioration related to the anaesthetic and surgery. MATERIALS, PATIENTS, AND METHODS: Children were randomized either to receive physiotherapy or not following anesthesia and intubation. Respiratory mechanics (C(rs) and R(rs)), tidal volume, and peak inspiratory pressure (PIP) were measured immediately before and after physiotherapy. FEV(1) was measured before and after surgery and post-operative physiotherapy requirements were recorded.

RESULTS

Eighteen patients, mean age 12 years (range 2.8-15 years) were recruited, with nine in each group. Both groups showed a non-significant decline in FEV(1) the day after surgery compared with pre-operative values (-5.8%: physiotherapy and -7.1%: control). Both PIP and R(rs) increased significantly following physiotherapy (within- and between-groups, P < 0.05). In addition, there was a significant within-group reduction in C(rs) after physiotherapy which approached significance between-groups (P = 0.07). There were no significant within- or between-group differences in tidal volume following treatment in either group.

CONCLUSION

The unanticipated decline in respiratory function immediately following physiotherapy was short-lived and not discernible in longer term outcomes measured by FEV(1) or physiotherapy requirements post-operatively. If respiratory physiotherapy under anesthesia is considered necessary and the benefits of removing secretions are deemed to outweigh the short-term risks, it may be necessary for the anaesthetist to consider modifying ventilatory support to counteract any short-term negative effects of the treatment.

A comparison of the prevalence of urinary incontinence in girls with cystic fibrosis, asthma, and healthy controls

Urinary incontinence (UI) is recognized as a significant problem in adult females with cystic fibrosis and can often have a marked impact on day-to-day activities. The prevalence and severity of UI in the pediatric cystic fibrosis (CF) female population is less clear and there are no comparative data with healthy children or children with other respiratory disorders. An anonymous self-completed semi-structured questionnaire was used to study the prevalence rates of UI in girls with CF aged between 11 and 17 and compared it to age-matched asthmatic and healthy girls. The prevalence of UI in girls with CF was significantly higher (17/51, 33%) than the asthmatic (4/25, 16%) and healthy girls (2/27, 7%) (P = 0.02). It may manifest as early as 11 years of age and is associated with increasing lung disease. Surprisingly it is perceived as a relatively minor problem in terms of the distress it causes. Pediatric CF clinics should be routinely addressing UI as a potential problem in all girls from the age of 11 years.

Gene therapy for children with cystic fibrosis--who has the right to choose?

It may be unethical to deny children with cystic fibrosis access to ethically approved clinical trials from which they might benefit

Factors that influence adherence to exercise and their effectiveness: application to cystic fibrosis

Appropriate, regular exercise is of benefit to patients with cystic fibrosis (CF). As with other segments of the population, it has been difficult to devise exercise programs to which most patients will adhere for long periods of time. In healthy children, factors that are related to positive exercise compliance include social support, perceptions of competency and self-esteem, enjoyment of activity, and availability of a variety of activities. In patients with CF, complications associated with the disease, e.g., time required for other treatment and fatigue, make compliance with recommended exercise activities more difficult. Factors likely to increase compliance in this population include explicit and continued encouragement and support from the family and healthcare team, and the introduction of behavior-changing strategies.

Exercise tolerance in children with cystic fibrosis undergoing lung transplantation assessment

The aim of this study was to compare the 6-min walk test against the recently developed 3-min step test, as measures of exercise tolerance in children with moderate to severe cystic fibrosis (CF) lung disease referred for lung transplantation assessment. Twenty-eight children with CF (16 girls, 12 boys), with a mean age of 13.7 yrs (range 7.2-17.8 yrs) and mean forced expiratory volume in one second of 34% predicted (range 17%-67%) were recruited. All subjects performed both the 6-min walk and 3-min step-tests. Outcome measures were maximum rise in heart rate (HR), and maximum fall in arterial oxygen saturation (Sa,O2). There was no significant difference in resting HR or Sa,O2 prior to starting the two tests. Both step and walk tests produced significant rises in median HR (from 114-149 min(-1), p<0.0005, and 119-138 min(-1), p<0.0005, respectively) and significant falls in Sa,O2 (both from 94-92%, p<0.0005). The step test produced a significantly greater percentage rise in HR (30% versus 18%, p<0.0005) and a significantly greater percentage fall in Sa,O2 (4% versus 2%, p=0.002). Bland-Altman analysis gave wide 95% limits of agreement (10.7-29.3% for rise in HR, -2.14.6% for fall in Sa,O2). The step test was well tolerated. The 3-min step test produced a greater fall in Sa,O2 and a greater rise in HR than the 6-min walk test in children with moderate to severe CF lung disease. It may be of value when assessing a child's suitability for lung transplantation.

Effect of intravenous antibiotics on exercise tolerance (3-min step test)) in cystic fibrosis

Most children with cystic fibrosis (CF) feel better and display more energy after a course of intravenous antibiotics (IVABs), but this is not always reflected by a satisfactory improvement in lung function. We assessed the change in exercise tolerance after treatment with IVABs using the 3-min step test, and compared it with changes in spirometric lung function and arterial oxygen saturation (SaO(2)). Thirty-six children (mean age, 13.8 years) were enrolled from two tertiary CF centers during an inpatient stay for IVABs. After 10-14 days of treatment, there was a significant improvement in median FEV(1) from 43% to 57% of predicted values (P < 0.0001), and median FVC from 66% to 73% of predicted values (P < 0.0001), while median SaO(2) significantly increased from 95% to 96.5% (P < 0.05). This was accompanied by a reduction in resting heart rate (median 118 bpm to 109 bpm, P < 0.005) and subjective breathlessness at rest (median visual analogue score 2.2 to 0.8, P < 0.005). All outcomes of exercise tolerance were improved after IVABs. There was a reduction in maximum heart rate (median 156 bpm to 150 bpm, P < 0.05) and an increase in minimum SaO(2) (median 93.5% to 94.5%, P = 0.08) measured during the step test. There was also a reduction in subjective breathlessness (median visual analogue score of 5.5 to 4.2, P < 0.005) and objective breathlessness (median 15-count score of 3 to 2, P < 0.0001) measured immediately after the step test. Exercise testing was a useful outcome measure for monitoring effectiveness of inpatient therapy, and complemented spirometry and SaO(2) monitoring. The simple ward-based 3-min step test was found to be a particularly suitable method for measuring changes in exercise tolerance in children with CF.

Heterosubtypic immunity to influenza A virus in mice lacking IgA, all Ig, NKT cells, or gamma delta T cells

The mechanisms of broad cross-protection to influenza viruses of different subtypes, termed heterosubtypic immunity, remain incompletely understood. We used knockout mouse strains to examine the potential for heterosubtypic immunity in mice lacking IgA, all Ig and B cells, NKT cells (CD1 knockout mice), or gamma(delta) T cells. Mice were immunized with live influenza A virus and compared with controls immunized with unrelated influenza B virus. IgA(-/-) mice survived full respiratory tract challenge with heterosubtypic virus that was lethal to controls. IgA(-/-) mice also cleared virus from the nasopharynx and lungs following heterosubtypic challenge limited to the upper respiratory tract, where IgA has been shown to play an important role. Ig(-/-) mice controlled the replication of heterosubtypic challenge virus in the lungs. Acute depletion of CD4+ or CD8+ T cell subsets abrogated this clearance of virus, thus indicating that both CD4+ and CD8+ T cells are required for protection in the absence of Ig. These results in Ig(-/-) mice indicate that CD4+ T cells can function by mechanisms other than providing help to B cells for the generation of Abs. Like wild-type mice, CD1(-/-) mice and gamma(delta) (-/-) mice survived lethal heterosubtypic challenge. Acute depletion of CD4+ and CD8+ cells abrogated heterosubtypic protection in gamma(delta) (-/-) mice, but not B6 controls, suggesting a contribution of gamma(delta) T cells. Our results demonstrate that the Ab and cellular subsets deficient in these knockout mice are not required for heterosubtypic protection, but each may play a role in a multifaceted response that as a whole is more effective than any of its parts.

Cutting edge: recombinant adenoviruses induce CD8 T cell responses to an inserted protein whose expression is limited to nonimmune cells

CD8 T cells (T(CD8+)) play a crucial role in immunity to viruses. Current understanding of activation of naive T cells entails Ag presentation by professional APCs (pAPCs). What happens, however, when viruses evolve to avoid infecting pAPCs? We have studied the consequences of this strategy by generating recombinant adenoviruses that express influenza A virus nucleoprotein under the control of tissue-specific promoters. We show that the immunogenicity of such viruses requires their delivery to organs capable of expressing nucleoprotein. This indicates that infection of pAPCs is not required for adenoviruses to elicit a T(CD8+) response, probably due to a cross-priming via pAPCs. While this bodes well for recombinant adenoviruses as vaccines, it dims their prospects as gene therapy vectors.

Fifteen-count breathlessness score: an objective measure for children

Breathlessness is an important symptom of respiratory disease and its quantification is useful, especially during exercise testing. However, measures of perceived breathlessness are not readily understood by children and are somewhat subjective. We studied an objective score: the 15-count breathlessness score, in which subjects take a deep breath and then count out loud to 15; the number of breaths taken to complete the count is the score. Fifty-four children with cystic fibrosis (CF) performed a standard 6-min walk and 3-min step test (30 steps/min for 3 min). The 15-count score was compared with the modified Borg scale after exercise. A further 45 children with CF and 33 healthy schoolchildren underwent an incremental step test (20, 30, and then 40 steps/min for 2 min each), using the 15-count score, then the Borg scale, and then a standard visual analogue score between increments. The 15-count score was significantly increased after both the walk and the step test (P < 0.0001), although the step test made children significantly more breathless than the walk test (P < 0.0001). At baseline, there were no differences in any of the breathlessness scores between the CF and normal children. After the full 6 min of the incremental step test, CF children were significantly more breathless than the normal children, as measured by 15-count (P < 0.0001), Borg (P < 0.0005), and visual analogue scores (P < 0.0005). All scores increased significantly as exercise intensity increased over time, but the slope estimates were significantly greater for CF patients than for normal children (P < 0.0005). The 15-count score has been evaluated as an objective measure of breathlessness. It is easy to explain and perform, and can be used by any child capable of counting fluently to 15 in any language. It is best used in conjunction with a subjective score, and either the Borg scale or a visual analogue score is appropriate.

Oxygen therapy for cystic fibrosis

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Finding evidence to support airway clearance techniques in cystic fibrosis

Chest physiotherapy, aiming to clear bronchopulmonary secretions, has become a mainstay in the respiratory management of cystic fibrosis (CF). Early diagnosis and new therapeutic interventions have dramatically improved the outlook for patients with this disorder and it is no longer a disease of childhood. Along with these changes chest physiotherapy has also progressed, with the development of several treatment modalities that are more effective and can be performed by the patient without assistance. This allows older children and adults with CF to lead more normal and independent lifestyles. Despite this progress questions remain regarding the efficacy and consequences of airway clearance techniques, the scientific evidence available to support the selection of the most appropriate treatment modality and, not least, the problems associated with the treatment-related burden that is placed on patients and their families.

A step in the right direction: assessing exercise tolerance in cystic fibrosis

Exercise tolerance may be reduced in patients with cystic fibrosis, but it is not always possible to predict this from standard lung function measurements. Formal exercise testing may, therefore, be necessary, and the test should be simple and readily available. We have developed a "3-minute step test" and compared it with the standard 6-minute walking test. Subjects stepped up and down a 15-cm-high single step at a rate of 30 steps per minute for 3 minutes. The effect of the step test on spirometry was tested first in 31 children with CF (mean age, 12.0 years), who had a mean (range) baseline forced expired volume in 1 second (FEV1) of 64% (18-94%) of predicted values. The step test was then compared with the standard 6-minute walk in a further 54 patients with cystic fibrosis (mean age, 12.5 years), with mean (range) baseline FEV1 of 61% (14-103%) of predicted values. Outcome measures were minimum arterial oxygen saturation (SaO2), maximum pulse rate, and the modified Borg dyspnea score. Post-step test spirometry showed mean (95% CI) changes of -1.1% (-6.0 + 3.9%) for forced vital capacity, of -1.6% (-4.2 + 1.1%) for FEV1, and +0.25% (-2.8 + 3.3%) for peak expiratory flow, although 5/31 children showed >15% drop in one or more parameters. The step and walk tests both produced significant changes (P < 0.0001) in all outcomes, with a mean (range) minimum SaO2 of 92% (75-98%) versus 92% (75-97%), a maximum pulse rate of 145 b.p.m. (116-189) versus 132 (100-161), and a Borg score of 2.5 (0-9) versus 1.0 (0-5), respectively. Comparison of the two tests showed that the step test increased breathlessness (mean change Borg score, 2.3 vs. 0.8; P < 0.0001) and pulse rate (mean change, 38% vs. 24%, P < 0.0001) significantly more than the walk, whereas the decrease in SaO2 was similar (mean change, -2.9% vs. -2.6%; P = 0.12). Some patients with a significant drop in SaO2 (>4%) would not have the decrease predicted from their baseline lung function. Reproducibility for the two tests was similar. The step test is quick, simple and portable, and is not dependent on patient motivation. Although the step test is more tiring, its effect on SaO2 is similar to the 6-minute walking test. It is a safe test that may prove to be a valuable measure of exercise tolerance in children with pulmonary disease, although longitudinal studies are now needed.

Calnexin expression does not enhance the generation of MHC class I-peptide complexes

We investigated the requirement for calnexin in the biogenesis of MHC class I molecules. Mutant human cells lacking calnexin were infected with recombinant vaccinia viruses encoding mouse MHC class I molecules, Kd, Kb, Kk, Dd, Db, and Ld. Flow cytometry indicated that each of the six MHC class I allomorphs was transported to the cell surface at similar rates in calnexin-deficient cells and transfectants expressing calnexin. For Kb and Kd, the calnexin-independent biogenesis occurred regardless of whether the MHC class I molecules contained human or mouse beta 2-microglobulin. Also addressed was the effect of calnexin on the surface expression of Kb molecules bearing the immunodominant peptide from ovalbumin (OVA257-264). This was detected with a recently described monoclonal antibody specific for the Kb/peptide complex. Calnexin expression had no significant effect on the formation of Kb/peptide complexes generated from full-length OVA, cytosolic OVA257-264, or endoplasmic reticulum-targeted OVA257-264, which was expressed in the presence of the herpes simplex virus ICP47 protein to ensure detection of TAP-independent peptide-MHC class I complexes. Complementary results were obtained with TAP-independent formation of Kd/ peptide complexes. These findings indicate that calnexin is not required for the efficient assembly of MHC class I molecules with TAP-dependent or independent peptides.

Antigen presentation in uveitis

Experimental autoimmune uveoretinits (EAU) is not only a valuable model for human inflammatory eye diseases, it is also a useful system for studying many aspects of immunobiology. One such aspect is self/non-self discrimination, the ability of the immune system to tolerate self molecules while responding aggressively to foreign antigens. Our laboratory has used EAU to investigate the mechanisms of T cell tolerance to retinal S-antigen (S-Ag). Several mechanisms have been proposed to maintain T cell tolerance to autoantigens, including clonal deletion and clonal anergy. As immunisation with S-Ag or pathogenic peptides activates uveitogenic T cells, tolerance to this autoantigen cannot be due to clonal deletion. Nevertheless, tolerance acts to keep these existing autoreactive T cells in a naive, or innocuous state. Here we suggest a novel mechanism--low-affinity occupancy of the autoantigen-specific T cell receptor (TCR) by self-antigen--that may act in concert with the well-known mechanisms to maintain tolerance to S-Ag in the LEW rat. This model differs from clonal anergy in that the missing antigen-presenting cell (APC) activity is not a co-stimulatory function but a TCR co-ligand that increases the avidity of the interaction between the TCR and its peptide-major histocompatibility complex (MHC) ligand. In the absence of this co-ligand only partial signals are generated through the TCR, leading to incomplete T cell activation. This model was deduced from experiments with T cell lines and hybridomas specific for S-Ag, which showed that: (1) autoreactive T cells required a novel APC function, (2) this novel function was necessary to provide complete TCR engagement, and (3) activation of autoreactive T cells was restricted to specific APC.

Differential APC requirements of self- and nonself-reactive T cells and T cell hybridomas specific for retinal S-antigen

Autoreactive T cell hybridomas specific for pathogenic peptides of retinal S-Ag require a novel radiosensitive APC activity for IL-2 secretion that is distinct from Ag presentation by MHC class II. Antigen-dependent IL-2 secretion by self-reactive hybridomas was much more efficient with splenic APC than with thymic APC, although both provided similar levels of hybridoma TCR occupancy as measured by activation-induced cell death. Furthermore, thymic APC did stimulate IL-2 secretion by a non-self reactive hybridoma. To test the hypothesis that this activity was provided by a distinct cell population, fractionated splenocytes were tested for their ability to present Ag to these hybridomas. The most potent Ag presentation for IL-2 secretion was found to segregate with low-density, B cell-enriched fractions while adherent cells, or purified T cells were unable to support IL-2 production. Together with previous results, the data show that antigen presentation leading to IL-2 secretion by these autoreactive T cell hybridomas requires activated B cells, whereas TCR occupancy can be provided by several APC subsets.

A radiosensitive APC activity dissociates IL-2 secretion and activation-induced cell death by autoreactive T cell hybridomas

T cell hybridomas were generated from a LEW rat T cell line specific for the uveitogenic peptide bov-B1 of bovine retinal S-antigen. Using these autoreactive hybridomas, IL-2 production and activation-induced cell death (AICD) were dissociated as outcomes of activation. The self-reactive hybridomas secrete IL-2 and undergo AICD in response to antigen presented by non-irradiated syngeneic splenocytes, whereas antigen presentation by irradiated splenocytes induced only AICD. IL-2 production by a non-self reactive hybridoma was unaffected by irradiation of the APC. Pretreatment of the APC with phorbol ester or lipopolysaccharide and IL-4 protected their ability to induce IL-2 secretion after gamma-irradiation. Although the co-stimulation-blocking reagent CTLA-4-Ig mimicked the effect of gamma-irradiation by preventing IL-2 secretion but not AICD, B7 expression on the APC was not radiosensitive, nor did co-stimulation, provided 'in trans' with a B7-expressing third-party cell, reconstitute antigen-specific hybridoma IL-2 secretion in response to irradiated APC. In summary, the data show that IL-2 secretion and AICD of a self-reactive T cell hybridoma can be dissociated as consequences of TCR occupancy in the presence of a functional co-stimulatory signal. It is proposed that the signals producing these events are transduced through the TCR-CD3 complex alone and reflect the differential outcomes of high- and low-affinity interactions.

Corneal endothelial cells inhibit T cell proliferation by blocking IL-2 production

We have reported that Ia+ LEW rat corneal endothelial (CE) cells could not induce Ag-specific proliferation of MHC compatible T cell lines. Instead, the presence of CE cell monolayers inhibited T cell proliferation assays. We now report on the effect of CE cells on IL-2 production, IL-2R expression, and IL-2 responsiveness of T cells. Ag-specific growth inhibition of the 1C3.4 T cell hybridoma was unaffected by the presence of CE cells but IL-2 production was suppressed by CE cells. Similar CE cell-mediated inhibition of IL-2 secretion was found with fresh splenic lymphocytes stimulated by Con A. Controls showed that neither CE cells nor their supernatant affected the CTLL cell response to rIL-2, allowing reliable measurement of IL-2 production. Further evidence that the block is at the level of IL-2 production was shown by the observation that IL-2R expression was up-regulated after TCR occupancy whether or not CE cells were present. Also, T cells expressing IL-2R were responsive to exogenous rIL-2 whether or not CE cells were present. CE cells themselves do not induce IL-2R expression or IL-2 responsiveness. Under normal culture conditions, the R1170 rat T cell line continually expresses a significant level of IL-2R and dies before IL-2R is down-regulated to background levels. However, in the presence of CE cells, these R1170 cells down-regulate IL-2R and lose IL-2 responsiveness while remaining viable.

Corneal endothelial cells inhibit T cell proliferation by blocking IL-2 production

We have reported that Ia+ LEW rat corneal endothelial (CE) cells could not induce Ag-specific proliferation of MHC compatible T cell lines. Instead, the presence of CE cell monolayers inhibited T cell proliferation assays. We now report on the effect of CE cells on IL-2 production, IL-2R expression, and IL-2 responsiveness of T cells. Ag-specific growth inhibition of the 1C3.4 T cell hybridoma was unaffected by the presence of CE cells but IL-2 production was suppressed by CE cells. Similar CE cell-mediated inhibition of IL-2 secretion was found with fresh splenic lymphocytes stimulated by Con A. Controls showed that neither CE cells nor their supernatant affected the CTLL cell response to rIL-2, allowing reliable measurement of IL-2 production. Further evidence that the block is at the level of IL-2 production was shown by the observation that IL-2R expression was up-regulated after TCR occupancy whether or not CE cells were present. Also, T cells expressing IL-2R were responsive to exogenous rIL-2 whether or not CE cells were present. CE cells themselves do not induce IL-2R expression or IL-2 responsiveness. Under normal culture conditions, the R1170 rat T cell line continually expresses a significant level of IL-2R and dies before IL-2R is down-regulated to background levels. However, in the presence of CE cells, these R1170 cells down-regulate IL-2R and lose IL-2 responsiveness while remaining viable.

Current concepts in physiotherapy

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