Flow cytometric analysis of T-lymphocytes subsets in adult Thais.

Flow cytometer (FACScan) was used to determine the range of T lymphocyte subpopulations in normal Thai blood donors at Maharaj Nakorn Chiang Mai Hospital, Chiang Mai. Reference population consisted of 150 healthy HIV seronegative blood donors. T lymphocyte subsets were analysed using two-color immunophenotyping of peripheral blood lymphocytes with a lysed whole blood technique and enumerated. The study showed that the normal values for CD3+ lymphocytes (percent), CD4+ lymphocytes (percent), CD8+ lymphocytes (percent), CD4/CD8 ratio, absolute CD3+ lymphocyte count, absolute CD4+ lymphocyte count and absolute CD8+ lymphocyte count were 64 +/- 8.8, 36.1 +/- 6.4, 25.7 +/- 7.3, 1.5 +/- 0.6, 1,630 +/- 600 cells/microl, 910 +/- 300 cells/microl and 670 +/- 350 cells/microl, respectively. We found that the values of CD3, CD4 and CD4/CD8 ratio were significantly lower than those in the Caucasians but those of CD8 was not significantly different. This observations have important clinical implication for the use of T lymphocyte subsets measurement, especially in the management of HIV infection in Thais. These normal ranges can be used as a reference for the decisions in clinical practice.

Determination of antibody from typhoid patients against lipopolysaccharide and protein antigens of Salmonella typhi.

Although the Widal test is simple, inexpensive and the most widely used for serodiagnosis of typhoid fever, the sensitivity and specificity of the test is sometimes doubtful. In this study, an enzyme-linked immunosorbent assay (ELISA) was developed for the detection of serum IgG and IgM antibodies to protein and lipopolysaccharide (LPS) antigens of Salmonella typhi which was compared with the Widal test in various groups of subjects. In typhoid patients with hemocultures positive for S. typhi (TP group), ELISA positivity was found on 100% for IgG antiprotein, 94.44% for IgG anti-LPS and 88.89% for IgM to both the protein and LPS antigens. In contrast, the Widal test was positive in only 61.11% for anti-O and 83.33% for anti-H antibodies. In healthy control subjects (HC group), only 5% of serum samples were positive for IgG anti-protein and none was positive for IgG anti-LPS or IgM to either the protein or LPS. In contrast, the Widal test was positive in 7.5% of HC group for anti-O and 17.5% for anti-H antibodies. In blood bank donors (BB group), both ELISA and Widal tests were positive in 23-40% of sera. Since the hospital records of BB group were incomplete. It might be possible that some of these subjects had recently been infected with S. typhi. Our data indicate that the standard Widal test was associated with false negative reactions in 16-39% of blood culture positive subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

First report case of cryoglobulinemia and cryofibrinogenemia in Thailand.

A 43-year-old monk had generalized purpura, arthritis of both shoulders, erythrocyanosis of lip and oral mucous membrane, Raynaud's phenomenon and uveitis. Platelets were normal. Cryoglobulin and cryofibrinogen were positive. Biopsy revealed vasculitis. No underlying infection, collagen vascular disease, lymphoproliferative, myeloproliferative and malignancy were found. He was diagnosed as having essential cryoglobulinemia and cryofibrinogenemia.

Adrenergic urticaria: a first report from Thailand.

A 22-year-old, female patient came to see the allergists because of a 10-year history of chronic urticaria. Widespread pruritic, urticarial papules developed at times of stress and exercise, each papule being surrounded by a striking blanched vasoconstricted halo. The halo hives could be replicated with an intradermal injection of adrenaline. This is the first report of adrenergic urticaria from Thailand.

Enumeration of interleukin 2-producing cells from rat spleen.

A method for the enumeration of IL2-producing cells from rat spleen has been developed. Rat spleen cells were stimulated with concanavalin A (Con A), washed, then mixed with IL2-dependent cells (3 day Con A blasts) and plated in soft agar. Clusters of IL2-dependent cells formed around IL2-producing cells, giving colonies which were easy to count under a dissecting microscope. All experimental factors influencing development of colonies of IL2-producing cells surrounded by IL2-dependent cells were evaluated and set up. Optimum number of effector cells was 2.5 x 10(5) cells/culture, while optimum number of IL2-dependent cells was 6 x 10(6) cells/culture. Optimum concentration of Con A for IL2 stimulation was 40 micrograms/ml with an optimal stimulation time of 10 hours. Optimum incubation time for development of IL2-producing cell colonies was 5 days. The number of IL2-producing cells by this technique had a good correlation with the level of IL2 in the cell culture fluid (r = 0.885). When colonies were aspirated from agar and stained by Wright stain, a big purple stained cell at the center was surrounded by small cells in almost all colonies examined. All cells from colonies were fluoresed with anti-mouse Thy 1.2-fluorescein conjugate. However, they were negative with anti-mouse Ig-fluorescein conjugate. The number of IL2-producing cells was 816-2080 cells/10(6) of rat spleen cells with mean +/- S.E.M. = 1404 +/- 154/10(6) cells.

Regulation of immunoglobulin secretion by T lymphocytes in human malaria.

In vitro studies were carried out on the nature of immunoglobulin synthesis and secretion by peripheral blood mononuclear leukocytes (PBMLs) and on the function of T and B cells from malaria patients. The mean values of secreted IgG and IgM concentrations of 22 malaria patient PMBLs were significantly higher than those of 20 normal PBMLs. When the suppressor T cell activity and the function of B cells in response to suppressor T cells were assayed by the cell co-culture technique, it was found that there was a decrease in suppressor T cell activity and the B cell function in response to normal suppressor T cells in malaria patients. The defects of these T and B cell functions may play some role in the immunological abnormalities seen in some malaria patients.

Lymphocyte transformation in lepromatous leprosy: a study of the influence of disease activity and symptom duration.

The lymphocyte hyporesponsiveness to M. leprae of patients with active lepromatous leprosy has been well described. This immune defect is less well understood in terms of its time of origin, possible reversibility and specificity. To further examine the persistence and specificity of this abnormality, lymphocyte transformation tests of 93 leprosy patients to lepromin, BCG and PHA were studied. Among lepromatous patients, a decreased response to M. leprae was seen, whether the disease was active or inactive. Decreased responses to BCG were found in lepromatous patients with active disease, but not in those with inactive disease. The duration of patient symptoms was not associated with differences in LTT responses among the active lepromatous patients.