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Background: An alarming increase in the number of patients with chronic and recurrent dermatophytosis has invoked the need to study the immunological parameters of the host., Objectives: To evaluate delayed type of hypersensitivity (DTH) response and immediate hypersensitivity (IH) response by flow cytometry evaluation of immune cells from peripheral blood and intradermal trichophyton skin test in patients with recurrent dermatophytosis., Methods: A hundred patients with recurrent dermatophytosis and 50 controls (healthy controls and acute dermatophytosis controls) were included. Relevant risk factors for recurrence were analysed, and serum IgE levels were estimated. Flow cytometry evaluation of immune cells in peripheral blood and intradermal trichophyton skin test was done. Dermatophyte pathogens were isolated, and antifungal susceptibility was performed., Results: Trichophyton mentagrophytes complex (95.84%) and T. rubrum (4.16%) were isolated in culture. Serum IgE was elevated in 83.15% cases (p = .01). IFN-γ + cells (p = .0501, p = .0001, p = .0014), Th1 cells (p = .1197, p = .0024, p = .0169), IL-17 + cells (p = .0127, p = .0006, p = .0007) and Th17 cells (p = .0634, p = .0001, p = .0054) were reduced, and IL-4 + cells (p = .0108, p = .0175, p = .0018) were increased in cases. Intradermal test demonstrated negative DTH response in all cases (p < .001, p < .001, p < .001), strongly positive IH response in 6%, and borderline positive IH response in 85% cases (p = .018, p < .001, p < .001). Topical corticosteroids application, undergarment types (tight fit), poor frequency of washing clothes, family history of tinea, sharing of towels were significant risk factors for recurrent dermatophytosis., Conclusions: Reduced IFN-γ + , Th1, IL-17 + and Th17 cells population along with impaired DTH response by the intradermal test was observed in patients with recurrent dermatophytosis., (© 2021 Wiley-VCH GmbH.)

Mangifera indica Linn, a plant widely used in the traditional medicinal systems of India, has been reported to possess antiviral, antibacterial and anti-inflammatory activities. In the present study, the alcoholic extract of stem bark of Mangifera indica Linn (Extract I containing mangiferin 2.6%), has been investigated for its effect on cell mediated and humoral components of the immune system in mice. Administration of test extract I produced increase in humoral antibody (HA) titre and delayed type hypersensitivity (DTH) in mice. It is concluded that test extract I is a promising drug with immunostimulant properties.

A total of 139 guineapigs were used to study the immune response and its modulation induced by Mycobacterium avium complex (MAC) and M. fortuitum complex strains obtained from different sources in the south Indian BCG trial area. The guineapigs were divided into groups and some were directly sensitised/immunised with different MAC strains. M. fortuitum complex strain or BCG and others were sensitised with MAC or M. fortuitum complex and then immunised with BCG. The resulting delayed type hypersensitivity (DTH) response in the different groups of guineapigs was studied by skin tests using PPD-RT23 and PPD-B, and protective response was studied by challenging the guineapigs with a south Indian low virulent strain of M. tuberculosis and enumerating the bacilli in spleen at different points of time. The 3 strains of MAC induced similar low levels of DTH to PPD-RT23 but much higher and varying levels of DTH to PPD-B. MAC strains from soil and sputum induced different levels of immune modulation during subsequent immunisation with BCG on the DTH response to PPD-RT23 and PPD-B. At 2 wk after challenge, 23.8, 81 and 90.5 per cent protection was induced by the standard strain, soil isolate and sputum isolate of MAC, respectively, while 33.3 per cent protection was induced by the M. fortuitum complex strain compared to the protection induced by BCG alone. Prior exposure to MAC or M. fortuitum complex did not have any modulatory effect on the protective immunity due to BCG at this time point. However, at 6 wk after challenge, while the guineapigs immunised with BCG were protected, modulation of the protective response resulting from BCG was observed in the guineapigs sensitised with MAC and M. fortuitum from soil.

A leishmanin test survey was carried out in a village during the declining phase of an outbreak of Indian kala-azar. One hundred and fifty of the total population of 220, including 25 clinically cured cases of kala-azar, were available for this study. Nineteen per cent (24 of 125) of the otherwise normal subjects showed delayed hypersensitivity to leishmanin antigen. The majority of these were household contacts of kala-azar patients, and the remainder came from the close neighbourhood. This may support the view that microfoci are of importance in the spread of the disease. The age-specific profile of leishmanin positivity was found to increase steadily, attaining a high level in older age groups.

Cell-mediated immune (CMI) response in 16 Indian kala-azar (KA) and 12 post-kala-azar dermal leishmaniasis (PKADL) patients was studied in detail by in vitro lymphocyte transformation experiments and by in vivo skin testing. Peripheral blood lymphocytes of active KA patients failed to be stimulated by leishmania antigen. On the other hand, lymphocytes from a majority of the active KA patients could be stimulated by phytohemagglutinin. Active KA patients also failed to show delayed type hypersensitivity reaction to leishmanin, although 72% of them showed delayed type hypersensitivity to a purified protein derivative of tuberculin. Longitudinal studies indicated that antigen-specific CMI response usually appeared in treated KA patients after 12 to 20 weeks of antileishmanial drug therapy, although individual variations were noted. CMI response in PKADL patients was variable as about two-thirds of them showed positive sensitization to leishmania antigen in either in vivo or in vitro tests. Usually, patients with newly acquired PKADL exhibited better CMI response than those with chronic PKADL. However, lymphocytes from all of these patients could be stimulated normally by phytohemagglutinin. Results presented in this study show an impairment of CMI response in active KA which appears to be more specific to leishmania than generalized in nature. Moreover, restoration of specific T-cell responsiveness was aided by antileishmanial drug therapy which resulted in the reduction of antigenic load by parasite destruction and a concomitant decrease in circulating antibody levels, particularly that of the immunoglobulin G class. We suggest that the protection afforded by specific CMI response against Leishmania donovani infection may not be absolute and probably depends on other host-related factors leading to parasite destruction and patient recovery.

In this study early lepromin reaction has been used to detect delayed hypersensitivity reaction to a prior infection with M. leprae, recent studies indicate that a certain number of contacts who develop sub-clinical infection remain anergic to the lepromin test. This is indicated by the Fluorescent leprosy antibody absorption (FLA-ABS) test of Abe (1979) which detects antibodies in the sera of infected individuals. Correlation of this serological test with lepromin response in contacts is in progress in the CJIL, Agra. These anergic contacts are likely to be susceptible to leprosy, a finding which would help in taking prophylactic measures.

The immunobiological activity was investigated of certain medicinal plants widely used in the Ayurvedic and Unani systems of medicine for treatment of chronic infections and immunological disorders. The effect of an ethanolic extract of each drug was studied on delayed type hypersensitivity, humoral responses to sheep red blood cells, skin allograft rejection, and phagocytic activity of the reticuloendothelial system in mice. Picrorhiza kurroa was found to be a potent immunostimulant, stimulating both cell-mediated and humoral immunity. Tylophora indica, Aconitum heterophyllum and Holarrhena antidysenterica appeared to stimulate phagocytic function while inhibiting the humoral component of the immune system. Tinospora cordifolia and Ocimum gratissimum appeared to improve the phagocytic function without affecting the humoral or cell-mediated immune system. Hemidesmus indicus suppressed both the cell-mediated and humoral components of the immune system.

This is a selective review, which, after recalling some immunological aspects, analyses the present knowledge on the protective efficacy of BCG vaccination, the vaccination reactions and complications that may be observed, and current methods of vaccine production and control. As regards the application of BCG vaccination, particular attention is given to dosage and vaccination techniques, direct and simultaneous vaccination, and revaccination. Finally, the evaluation of BCG vaccination programmes is briefly discussed.

Allergic bronchopulmonary aspergillosis is reported in two (1.5%) of 131 workers occupationally exposed to Aspergillus fumigatus at the U.D. Sugar Mills, Shamli. Twelve of the workers revealed Type I (9.2%) and three (2.8%) Type III skin hypersensitivity against with fungus. Serum preciptins were demonstrated in two out of 44 workers and positive sputum cultures in 26 out of 58 workers. It is suggested that constitutional predisposition of the host may be a more important factor than the extent of exposure to the fungus in the development of allergic bronchopulmonary aspergillosis.

Previous studies on the influence of isoniazid on the size of the tuberculin reaction have given conflicting results. A controlled study in an area with high prevalence of low-grade allergy has been carried out by the administration of isoniazid or placebo tablets. For those not vaccinated with BCG, isoniazid in a single daily dose of 5 mg/kg body-weight tended to reduce somewhat the size of the tuberculin reaction among those with reactions of 12 mm or more at the initial tuberculin test.In people who were vaccinated with BCG, isoniazid given simultaneously resulted in significantly less increase in the size of post-vaccination tuberculin reactions as compared with controls; the difference was still significant, in tests conducted 4(1/2) months after the discontinuation of isoniazid. However, in spite of isoniazid, the post-vaccination allergy induced by BCG was quite considerable. This considerable increase in post-vaccination allergy suggests that the vaccination was successful in spite of the administration of isoniazid and makes it clear that primary chemoprophylaxis could be combined with BCG vaccination.Administration of isoniazid for 2 months is estimated to have killed about 90% of the bacilli in the BCG vaccine injected intracutaneously.