Studies of immunoglobulins, bentonite flocculation and IgE, IgG and IgM antibodies in serum from patients with trichinosis

New aspects of human trichinellosis: the impact of new Trichinella species

Trichinellosis is a re-emerging zoonosis and more clinical awareness is needed. In particular, the description of new Trichinella species such as T. papuae and T. murrelli and the occurrence of human cases caused by T pseudospiralis, until very recently thought to occur only in animals, requires changes in our handling of clinical trichinellosis, because existing knowledge is based mostly on cases due to classical T spiralis infection. The aim of the present review is to integrate the experiences derived from different outbreaks around the world, caused by different Trichinella species, in order to provide a more comprehensive approach to diagnosis and treatment.

Kinetics of humoral response during the acute and the convalescent phase of human trichinosis

After a common source outbreak of trichinosis in Bitburg, FRG, 107 patients, for whom time and source of infection were precisely known, were prospectively studied for a period of eight months in order to investigate the kinetics of the humoral immune response. Antibodies were assessed by IHA, and by ELISA to quantify IgG, IgM and IgE isotypes. For four different periods of the observation time sensitivity and predictive value of tests to identify acute or convalescent trichinosis were determined. The results demonstrated characteristic kinetics of the different antibody isotypes and varying diagnostic value of the tests. Only IgG-ELISA and double-sandwich IgM-ELISA reliably identified diseased patients shortly after onset of clinical illness and showed a negative predictive value of almost 100% from seven weeks to eight months after infection. IgE antibodies and elevation of total serum IgE occurred only in about 20% of patients and showed no consistent pattern during the course of the disease. Circulating immune complexes were moderately increased four weeks after infection. They rapidly returned to normal values, after the symptoms of the acute phase had disappeared.

Study of acute trichinosis in Ghurkas: specificity and sensitivity of enzyme-linked immunosorbent assays for IgM and IgE antibodies to Trichinella larval antigens in diagnosis

The enzyme-linked immunosorbent assay (ELISA) was successfully applied to detect IgE antibodies against parasitic antigens by using an additional antibody layer to attain an amplification effect. The sera of 18 Gurkha patients with clinical manifestations of acute trichinosis and 35 Chinese with other parasitic infections were tested for antibodies to Trichinella spiralis by IgE-, IgM- and IgG-ELISA, IgG-radioimmunoassay (RIA) and indirect haemagglutination test (IHA). ELISAs for detection of IgE and IgM antibodies provided a 100% specific and sensitive diagnosis. Although IHA, IgG-RIA and IgG-ELISA detected antibodies in 94% of patients, non-specific reactions were also observed in the two last named methods. Muscle biopsies were positive in only 56% of patients.

Human antihapten antibodies in trimellitic anhydride inhalation reactions. Immunoglobulin classes of anti-trimellitic anhydride antibodies and hapten inhibition studies

Inhalational exposure to trimellitic anhydride (TMA) produces an immediate-type asthmatic or a late respiratory systemic syndrome in certain workers after a latent period of work exposure. TMA has been found to react with proteins to produce a hapten-protein complex (trimellitate [TM] protein) or become hydrolyzed in aqueous, alkaline solutions to produce a salt, NaTM. Using a solid-phase radioimmunoassay technique, antibodies of different Ig classes were detected against TM-protein conjugates. IgE antibody was detected in three of five workers with asthma. IgG and IgA antibodies were detected in most exposed workers but higher levels of antibody were found in symptomatic workers even after long periods without direct TMA exposure. IgM antibody activity against TM-human serum albumin (TM-HSA) was detected but did not differentiate symptomatic from asymptomatic workers. NaTM served as a hapten for study because it does not react with proteins to form a hapten-protein complex as TMA does. The NaTM only partially inhibited IgG antibody activity against TM-HSA and much smaller amounts of TM-HSA than of NaTM were required to neutralize IgG antibody. A similar result was found with TM-ovalbumin. The latter results suggest that some IgG antibody is directed against a TM-protein moiety, probably a TM-amino acid determinant. In contrast to IgG, marked inhibition by NaTM of IgA and IgM antibody against TM-HSA was found in the sera studied.

Evidence that Aspergillus fumigatus growing in the airway of man can be a potent stimulus of specific and nonspecific IgE formation

Serum IgE levels in patients with allergic bronchopulmonary aspergillosis are elevated but the degree of elevation varies markedly. Serum IgE levels in patients with aspergillomas may be strikingly elevated or normal. Absorption of serums with antigens of Aspergillus fumigatus combined with a solid phase radioimmunoassay technic demonstrated that both immunoglobulin E (IgE) and immunoglobulin G (IgG) antibody activity against A. fumigatus were markedly reduced without a parallel reduction in serum total IgE. These results indicate that the very high levels of serum IgE found in allergic bronchopulmonary aspergillosis and aspergilloma are not all specific IgE. These results are similar to those observed in rats infested with Nippostrongylus brasiliensis. An explanation for the elevations of IgE levels in infestations with A. fumigatus may be analogous to the postulate that parasite-produced materials may result in T cell stimulatory factors for IgE-producing cells. Alternatively, A. fumigatus organisms may produce materials that inhibit T suppressor lymphocytes.

Variation in serum immunoglobulin levels in acute trichinosis

An early rise in serum IgE levels was observed in five of seven patients with acute primary trichinosis. Parallel increases in the total IgG, IgM, and Iga levels, as well as specific IgG and IgM antibody titres to Trichinella spiralis larval antigen, were detected in two. The elevated levels persisted long after the clinical recovery of the patients.

Pigeons breeders' disease. I. Serum immunoglobulin concentrations; IgG, IgM, IgA and IgE antibodies against pigeon serum

The clinical course of a patient with severe acute and chronic hypersensitivity pneumonitis of the pigeon breeders' disease (PBD) type was evaluated. A significant remission of symptomatic, roentgenographic and pulmonary function abnormalities occurred after cessation of exposure to antigen. Immunoglobulin G (IgG), A (IgA) and M (IgM) antibody activity against pigeon serum was demonstrated in the patient's serum by a solid phase radioimmunoassay (RIA) technic. The levels of these antibodies fell subsequent to elimination of antigen inhalation. The RIA technic was used to demonstrate IgG, IgA and IgM antibody activity in single serum samples of four other patients with PBD, and this technic may have diagnostic value. Although no immunoglobulin E (IgE) antibody was demonstrable by RIA, a heat-liable, reaginic antibody was also detectable in the serum of the primary case. In addition, Arthus type cutaneous reactivity was passively transferred to the skin of a volunteer subject using heated serum from a patient with PBD.