Immunoelectrophoretic determination of tear fluid proteins collected by the Schirmer I test

Patient acceptability of tear collection in the primary healthcare setting

Purpose

The primary healthcare setting is well placed for health screening. Tear fluid composition gives valuable information about the eye and systemic health, and there is now significant interest in the potential application of tears as a tool for health screening; however, the acceptability of tear collection in the primary healthcare setting as compared with other methods of human sample collection has not been previously addressed. The objective of this study was to evaluate the patient acceptability of tear collection in a primary healthcare setting.

Methods

This was a cross-sectional study on 383 adult patients seeking primary healthcare, who were not diabetic and were not attending for an eye-related complaint. Tear collection was done using Schirmer strips, and an interviewer-administered questionnaire was conducted to collate information on the pain score (0–10) of the Schirmer tear collection, as well as to score the pain associated with their previous experience of antecubital venous puncture and finger prick test.

Results

The pain score for Schirmer tear collection was significantly lower (p < 0.001) than antecubital venous puncture but higher (p < 0.001) than finger prick. The pain scores for all three procedures were significantly higher in participants of younger age, female gender, and higher education level. Among the participants, 70% did not mind their tears being collected to screen for eye problems, whereas only 38% did not mind this procedure being performed for general health screening. Nevertheless, 69% of the participants preferred tear to urine collection, and 74% of participants preferred tear to blood collection.

Conclusions

Tear collection using Schirmer strips is a highly acceptable form of investigation that has the potential for use in health screening in the primary healthcare setting. This study has implications on using tear collection as a method of ocular and systemic health screening in the primary healthcare setting.

Tear analysis in ocular surface diseases

The thin layer of tears covering the ocular surface are a complex body fluid containing thousands of molecules of varied form and function of several origins. In this review, we have discussed some key issues in the analysis of tears in the context of understanding and diagnosing eye disease using current technologies of proteomics and metabolomics, and for their potential for clinical application. In the last several years, advances in proteomics/metabolomics/lipidomics technologies have greatly expanded our knowledge of the chemical composition of tear fluid. The quickened pace of studies has shown that tears as a complex extra-cellular fluid of the ocular surface contains a great deal of molecular information useful for the diagnosis, prognosis, and treatment of ocular surface diseases that has the ability to addresses the emphasis on personalized medicine and biomarkers of disease. Future research directions will likely include (1) standardize tear collection, storage, extraction, and sample preparation; (2) quantitative proteomic analysis of tear proteins using multiple reaction monitoring (MRM)-based mass spectrometry; (3) population based studies of human tear proteomics/metabolomics; (4) tear proteomics/metabolomics for systemic diseases; and (5) functional studies of tear proteins.

Sialochemistry in Sjögren's syndrome: a review

Sjögren's syndrome (SS) is an autoimmune exocrinopathy. The salivary glands are the site of activated T- and B-lymphocytes, along with gradual parenchymal destruction, diminished flow and altered composition of the secretory product. At present, sialochemistry has achieved no significance for the evaluation of SS patient. However, the number of sialochemical publications is steadily growing. This study review current sialochemical findings in patients with SS and relate the observations to the present concept of diagnosis, pathogenesis and prognosis of SS. An ideal combination of the collection of low-stimulated pure secretion, measurements of absolute flow-rates, and biopsy from the same glands seem to be unobtainable in SS patients. But two procedures may be appropriate: stimulated parotid secretion combined with parotid biopsies, or absorbance of low-stimulated labila saliva combined with labial gland biopsy. Sufficient data on disease-specific alterations in salivary composition in SS are still lacking. However, detection of specific changes in protein synthesis or in glycosylation as well as the detection of inflammatory cell products should be possible with the use of sensitive biochemical assays.

The measurement of IgE in tear fluid: a comparison of collection by sponge or capillary

We have used commercially available reference concentrations of immunoglobulin E (IgE) and tear samples from atopic patients to compare the recovery of IgE from fluid collected in cellulose sponges or glass capillary tubes. There was no statistically significant difference in the values for IgE in the reference samples recovered from capillaries or sponges (P = 0.16), but at some concentrations both methods produced a higher reading than the control samples (P less than 0.001). There was no significant difference when the values for IgE in the first or second of paired tear samples were compared using either sponges or capillaries for collection, but the mean value of samples collected by capillary tubes was lower (P = 0.02). The collection of tears in sponges for IgE estimation is less time consuming than capillary collection and for clinical practice it is as sensitive as collection in capillaries.

Recovery of protein from tear fluid stored in cellulose sponges

Human tear fluid collected in glass capillaries was absorbed in cellulose sponges. After various time intervals the recovery was measured for total protein, amylase (AMY), lysozyme (LZM), immunoglobulin A (IgA) and lactoferrin (LF). After one day storage at 4 degrees C of moistened sponges of at least 92% recovery was observed. Storage for longer periods at 4 degrees C up to seven days showed a decreasing recovery for total protein, AMY and IgA. Tear collection with sponges and storage of wet sponges for maximally one day at 4 degrees C followed by centrifugation or storage of the fluid at -20 degrees C are reliable ways of sample treatment.

Serum albumin, serum antiproteases and polymorphonuclear leucocyte neutral collagenolytic protease in the tear fluid of normal healthy persons

Using a micro-electroimmune assay and a 'non-reflex stimulating' method to collect normal tear fluid, the concentration of the serum proteins albumin (S-A), alfa-1-antitrypsin (alpha 1A), alfa-1-antichymotrypsin (alpha 1X) and alfa-2-macroglobulin (alpha 1M) was determined in the tear fluid of 53 normal persons. In addition, the tear fluid was tested for the content of polymorphonuclear leucocyte neutral collagenolytic protease (PML-c-ase). PML-c-ase and alpha 1X could not be detected in any tear samples. The concentrations of S-A, alpha 1A and alpha 1M were constant over time, and showed no variation with sex, age or between the right and left eyes. There was no correlation between the concentration levels of the detected proteins in the tear fluid and correlation between tear fluid levels and corresponding serum concentration levels of the proteins could not be shown.

Secretory IgA specific for herpes simplex virus in lacrimal fluid from patients with herpes keratitis--a possible diagnostic parameter

In the present study a solid-phase radioimmune assay was used for the demonstration of herpes simplex virus-specific IgG and secretory IgA antibodies in the lacrimal fluid from patients with active recurrent herpes keratitis. The method was quantitative and made it possible to test specifically for the production of secretory IgA antibodies produced during an active herpes simplex virus infection. The production of secretory IgA was followed in 2 patients with fresh recurrent lesions. The HSV-specific secretory IgA could be demonstrated during the first 10 days of infection, where the maximal concentration was reached 3-5 days after the first symptoms occurred. The secretory antibodies were locally produced, and it is shown for the first time that herpes virus-specific secretory antibodies were of diagnostic value.